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Sample records for investigations white sturgeon

  1. Kootenai River White Sturgeon Investigations; White Sturgeon Spawning and Recruitment Evaluation, 2003-2004 Annual Report.

    SciTech Connect

    Rust, Pete; Wakkinen, Virginia

    2005-06-01

    The objective of this research was to determine the environmental requirements for successful spawning and recruitment of the Kootenai River white sturgeon Acipenser transmontanus population. Annual tasks include monitoring and evaluating the various life stages of Kootenai River white sturgeon. Sampling for adult Kootenai River white sturgeon in 2003 began in March and continued through April. Eighty-one adult white sturgeon were captured with 3,576 hours of angling and set-lining effort in the Kootenai River. Discharge from Libby Dam and river stage at Bonners Ferry in 2003 peaked in May and early June. Flows remained above 500 m{sup 3}/s throughout June, decreased rapidly through mid July, and increased back to near 500 m{sup 3}/s after mid July and through mid August. By late August, flows had decreased to below 400 m{sup 3}/s. We monitored the movements of 24 adult sturgeon in Kootenay Lake, British Columbia (BC) and the Kootenai River from March 15, 2003 to August 31, 2003. Some of the fish were radio or sonic tagged in previous years. Twelve adult white sturgeon were moved upstream to the Hemlock Bar reach (rkm 260.0) and released as part of the Set and Jet Program. Transmitters were attached to seven of these fish, and their movements were monitored from the time of release until they moved downstream of Bonners Ferry. Eight additional radio-tagged white sturgeon adults were located in the traditional spawning reach (rkm 228-240) during May and June. Sampling with artificial substrate mats began May 21, 2003 and ended June 30, 2003. We sampled 717 mat d (a mat d is one 24 h set) during white sturgeon spawning. Three white sturgeon eggs were collected near Shortys Island on June 3, 2003, and five eggs were collected from the Hemlock Bar reach on June 5, 2003. Prejuvenile sampling began June 17, 2003 and continued until July 31, 2003. Sampling occurred primarily at Ambush Rock (rkm 244.0) in an attempt to document any recruitment that might have occurred from

  2. Kootenai River White Sturgeon Investigations; White Sturgeon Spawning and Recruitment Evaluation, 2004-2005 Annual Report.

    SciTech Connect

    Rust, Pete; Wakkinen, Virginia

    2006-05-01

    The objective of this research was to determine the environmental requirements for successful spawning and recruitment of the Kootenai River white sturgeon Acipenser transmontanus population. Annual tasks include monitoring and evaluating the response of various life stages of Kootenai River white sturgeon to mitigation flows supplied by the United States Army Corps of Engineers (USACE). Sampling for adult Kootenai River white sturgeon in 2004 began in March and continued into May. One hundred forty-two adult white sturgeon were captured with 4,146 hours of angling and set-lining effort in the Kootenai River. Kootenai River discharge and stage at Bonners Ferry in 2004 peaked in mid December. Discharge remained below 400 cubic meters per second (cms) until June 1; then, because of a systems operations request (SOR), increased and remained between 480 and 540 cms through the end of June. From July through September, discharge ranged from 360 to 420 cms, decreasing to 168 cms by the end of October. Discharge increased again to above 625 cms by November 4 to increase winter storage in Lake Koocanusa and ranged from 310 to 925 cms through the end of December. We monitored the movements of 31 adult sturgeon in Kootenay Lake, British Columbia (BC) and the Kootenai River from mid-March until late August 2004. All telemetered fish were dual tagged with external sonic and radio transmitters, and some of the fish were tagged in previous years. Eighteen of the 31 telemetered adult white sturgeon were released at Hemlock Bar reach (rkm 260.0) as part of a research project to test the feasibility of moving sexually mature adult white sturgeon to areas with habitat types thought to be more suitable for successful egg hatching and early life stage recruitment. Marked fish were monitored from the time of release until they moved downstream of Bonners Ferry. Sampling for white sturgeon eggs with artificial substrate mats began May 3 and ended June 10, 2004. We sampled 650 mat days

  3. Kootenai River White Sturgeon Investigations; White Sturgeon Spawning and Recruitment Evaluation, 1999 Annual Report.

    SciTech Connect

    Paragamian, Vaughn L.; Kruse, Gretchen L.; Wakkinen, Virginia

    2001-11-01

    Sampling for adult Kootenai River white sturgeon Acipenser transmontanus began in March and continued through April 1999. Forty-six adult sturgeon were captured with 4,091 hours of angling and set-lining effort, while an additional three adult sturgeon were captured during gillnetting for juveniles. Flows for Kootenai River white sturgeon spawning were expected to be high because the snow pack in the basin was estimated at 130% of normal, but runoff came very slowly. Discharge from Libby Dam from mid-March through mid-June was maintained at 113 m{sup 3}/s (4,000 cfs). Flows in the Kootenai River at Bonners Ferry during early April, including local inflow, were 227-255 m{sup 3}/s (8,000-9,000 cfs) but increased gradually in late April to a peak of 657 m{sup 3}/s (23,200 cfs). Flows subsided in early May to about 340 m{sup 3}/s (12,000 cfs), but rose to 1,031 m{sup 3}/s (36,370 cfs) by Mary 26 because of local runoff, and white sturgeon began spawning. However, flows subsided again to 373 m{sup 3}/s (13,200 cfs) June 11, 1999 and some female white sturgeon with transmitters began leaving the spawning reach. Water temperature ranged from about 8 C to 10 C (45 F to 50 F) during these two weeks. On June 13 (two weeks after sturgeon began spawning), spawning and incubation flows from Libby Dam began. The flow was brought up to 1,136 m{sup 3}/s (40,100 cfs) and temperature rose to about 11 C (52 F). They sampled for 3,387 mat days (one mat day is a single 24 h set) with artificial substrate mats and captured 184 white sturgeon eggs. The Middle Shorty's Island reach (river kilometer [rkm] 229.6-231.5) produced the most eggs (144), with 388 mat days of effort; the Refuge section (rkm 234.8 to 237.5) with 616 mat days of effort produced 23 eggs; and the Lower Shorty's section produced 19 eggs with 548 days of mat effort. No eggs were collected above the Refuge section (> rkm 240.5) with 988 mat days of effort. They do not believe flows for sturgeon spawning in 1999 were very

  4. Kootenai River White Sturgeon Investigations; White Sturgeon Spawning and Recruitment Evaluation, 1996 Annual Report.

    SciTech Connect

    Paragamian, Vaughn L.

    1997-09-01

    Test flows for Kootenai River white sturgeon Acipenser transmontanus spawning, scheduled for June 1996, were postponed until July. However, an estimated 126% snow pack and unusually heavy precipitation created conditions for sturgeon spawning that were similar to those occurring before construction of Libby Dam. Discharge in the Kootenai River at Bonners Ferry rose to nearly 1,204 m{sup 3}/s (42,500 cfs) during May and water temperature ranged from 5.8 C to 8.4 C (42 F to 47 F). Migration of adult white sturgeon into spawning areas occurred in late May during a rising hydrograph. Discharge and water temperature were rising and had reached approximately 1,077 m{sup 3}/s (38,000 cfs) and 8 C (46 F). Discharge at Bonners Ferry peaked at about 1,397 m{sup 3}/s (49,300 cfs) on June 5. A total of 348 eggs (and one egg shell) were collected with 106,787 h of mat effort during the flow events. The first white sturgeon eggs were collected on June 8 and continued through June 30. Staging of eggs and back-calculating to spawning dates indicated there were at least 18 spawning episodes between June 6 and June 25. Discharge on June 6 was 1,196 m{sup 3}/s (42,200 cfs) and decreased steadily to 850 m{sup 3}/s (30,000 cfs) by June 26. Although sturgeon spawned in the same reach of river that they had during 1994 and 1995, the majority of eggs were found significantly (P = 0.0001) farther upstream than 1994 and 1995 and this in turn may be related to elevation of Kootenay Lake.

  5. Kootenai River White Sturgeon Investigations : White Sturgeon Spawning and Recruitment Evaluation, 1998 Annual Report.

    SciTech Connect

    Paragamian, Vaughn L.; Kruse, Gretchen L.; Wakkinen, Virginia

    2001-03-01

    Flows in the Kootenai River for white sturgeon Acipenser transmontanus spawning in 1998 were expected to be at a minimum because the snow pack in the basin was only about 79% normal, and local inflow was expected to be very low, <142 m{sup 3}/s (5,000 cfs). Flows in the Kootenai River at Bonners Ferry from late April through early May were at about 425 m{sup 3}/s (15,000 cfs) while water temperature ranged from about 8 to 10 C (45 to 50 F). Spawning and incubation flows from Libby Dam began on May 18 when flow at the dam was brought up to 765 m{sup 3}/s (27,000 cfs). Unusually frequent rains and several enormous storms brought peak flows at Bonners Ferry to over 1,175 m{sup 3}/s (41,500 cfs) on May 27, temperature ranged between 8 and 10.6 C (45 to 51 F). Flow gradually subsided at Bonners Ferry during June and was steady at 708 to 765 m{sup 3}/s (25,000 to 27,000 cfs) while temperature gradually rose to 14.4 C (58 F). Forty-seven adult white sturgeon were captured with 4,220 hours of angling and setlining effort between March 1 and April 15, 1998 by the Idaho Department of Fish and Game (IDFG). Sonic and radio tags were attached to four female and five male sturgeon during this effort. From April 1 through July 31, 1998, a total of 17 fish were monitored specifically for pre-spawn and spawning activities. White sturgeon spawning location, timing, frequency, and habitat were evaluated by sampling for eggs with artificial substrate mats. Four hundred and eighty-four eggs were collected, 393 eggs (81%) were collected on 60 standard mats, and 91 eggs (19%) were collected on seven experimental mats with drift nets. Ten eggs collected with experimental mats were found mixed with sand, suggesting eggs are moving in the lower water column with sand. The middle Shorty's Island reach (rkm 229.6-231.5) produced the most eggs (173) while the Deep Creek section (rkm 237.6-240.5) produced 112 eggs. No eggs were collected above the Deep Creek section (>rkm 240.5). Four hundred

  6. Kootenai River White Sturgeon Investigations, 1993 Annual Report.

    SciTech Connect

    Marcuson, Patrick E.

    1994-05-01

    U.S. Army Corps of Engineers in concordance with Bonneville Power Administration provided a release of 324.3 m{sup 3}/s (400,000 acre feet) of impounded water from Lake Koocanusa, Montana from June 2 to June 16, 1993. This release of water provided approximately 566.4 m{sup 3}/s (20,000 cfs) discharge in the Kootenai River at Bonners Ferry, Idaho. Nineteen adult white sturgeon equipped with combinations of radio and sonic transmitters were monitored from mid-April to mid-July, 1993. Nine females and one male remained in the Kootenai River near the British Columbia/Idaho border and/or Kootenay Lake, British Columbia. One female was captured by the crew from the Kootenai Hatchery, operated by the Kootenai Tribe of Idaho, delivered to the hatchery, tagged, and released seven days later. She retreated to Kootenay Lake immediately after release. Eight sturgeon with transmitters formed the aggregate of unknown numbers of fish in the staging area. The monitored fish were all judged late vitellogenic and were used to characterize what was assumed reproductive behavior of white sturgeon in the Kootenai River. Four late vitellogenic females moved upriver with the lowland spring runoff (May 11), lingered around the ''staging area'' May 11-24, then retreated downriver May 21-24. Two fish retreated all the way to Kootenay Lake, British Columbia; the other two re-advanced upriver May 27-30 concurrent with the initiation of the augmented discharge on May 28. None of the monitored fish were detected beyond the U.S. Highway 95 bridge. By June 4, the remaining females began moving downriver. Male sturgeon tended to move upriver seven days earlier than the females. They arrived in staging waters about May 11. On May 21, three male sturgeon demonstrated a slight downriver run the same time as did the females. The maximum downriver travel was 14.2 km. All four of the monitored males returned upriver just prior to and during the augmented flow period. Crews fished a combined 14

  7. Kootenai River White Sturgeon Investigation, 1994 Annual Report.

    SciTech Connect

    Marcuson, Patrick E.; Wakkinen, Virginia; Kruse-Malle, Gretchen

    1995-07-01

    The U.S. Army Corps of Engineers in concordance with Bonneville Power Administration provided a release of 1.48 billion cubic meters (1.2 MAF, million acre feet) of impounded water from Lake Koocanusa, Montana from June 1 to June 28, 1994. This release of water provided approximately 566 To/s (20 thousand cubic feet per second, kcfs) discharge in the Kootenai River at Bonners Ferry, Idaho. Between February and early April 1994, 15 adult sturgeon (10 females, 5 males) in late vitellogenic stage were captured and fitted with combinations of radio and sonic transmitters. A total of 31 sturgeon were monitored. Ten hatchery reared juvenile white sturgeon equipped with radio and sonic tags were released in pools down river of Kootenai Falls, Montana. All ten sturgeon had moved between 60 and 97 km (37.3 and 60.3 mi) down river of release sites within one month. Movements coincided with major flow peaking associated with hydropower production at Libby Dam, located upriver of the release site

  8. Kootenai River White Sturgeon Investigations and Experimental Culture, 1990-1991 Annual Report.

    SciTech Connect

    Apperson, Kimberly A.

    1992-07-01

    Setline and angling techniques were used to sample 56 white sturgeon Acioenser transmontanus from the Kootenai River in 1991. Of those sampled, nine were recaptures from previous years of this study. A total of 382 white sturgeon were captured from March 1989 through October 1991. Fork lengths of white sturgeon in the sample ranged from 88-274 cm. Our data indicated there was a complete lack of recruitment of juveniles into the population. The youngest fish sampled was of the 1977 year class. The population was estimated at 880 individuals with a 95% confidence interval of 638 to 1,211. Annual mortality of white sturgeon since 1982 is 3.74%. Approximately 80% of the population was more than 20 years old and was reproductively mature. Surgical examination of 309 white sturgeon since 1989 indicated that approximately 7% of the female white sturgeon and 30% of the male white sturgeon are reproductive each year. The ratio of males to females was estimated at 1:l. White sturgeon sampled and released with and without surgical examination were recaptured at equal rates. An ongoing sonic telemetry study has documented long distance movements by adults. White sturgeon regularly move across the British Columbia - Idaho border. White sturgeon seek out deep holes in the river or migrate to Kootenay Lake during late fall, During spring and early summer of both 1990 and 1991 reproductively mature white sturgeon moved from 15 to 110 km upriver and congregated within 10 km downriver from Bonners Ferry in areas of elevated water velocity. This behavior coincided with increasing discharge and water temperatures. Developing white sturgeon eggs were recovered from the river near Bonners Ferry on July 3, 1991. Contamination of eggs by organochloride compounds were less in recent samples from the Kootenai River than in a single sample collected in 1982. White sturgeon eggs from the Kootenai River fish contained approximately one tenth the organochloride compounds of white sturgeon eggs

  9. Kootenai River White Sturgeon Investigations and Experimental Culture, 1992 Annual Report.

    SciTech Connect

    Apperson, Kimberly A.; Wakkinen, Virginia (

    1993-11-01

    Setline and angling techniques were used to sample 64 white sturgeon Acipenser transmontanus from the Kootenai River in 1992. Of those sampled, 15 were recaptures from previous years of this study. A total of 429 white sturgeon were captured from March 1989 through September 1992. Fork lengths of white sturgeon in the total sample ranged from 88 to 274 cm. The data indicated there was a complete lack of recruitment of juveniles into the population which was estimated in 1990 at 880 individuals with a 95% confidence interval of 638 to 1,211. Annual mortality of white sturgeon from 1982 to 1991 was 0.0374. Approximately 80% of the population was more than 20 years old and was reproductively mature. An ongoing sonic telemetry study revealed long distance movements among adults. Sturgeon regularly moved across the British Columbia-Idaho border. Sturgeon used deep holes in the river or migrated to Kootenai Lake during late fall. During spring and early summer, reproductively mature sturgeon moved from 15 to 110 kilometers upriver and congregated within 15 kilometers downriver from Bonners Ferry in areas of elevated water velocity. This behavior coincided with increasing discharge and water temperatures. The authors monitored movements of five reproductively mature female white sturgeon. The fish responded to increasing then decreasing flows by moving upriver then downriver, respectively. All five fish quickly moved to Kootenai Lake when flows dropped suddenly from higher than 20 kcfs to less than 10 kcfs. One fish was recaptured and was reabsorbing eggs. Trawling and sampling with mats of artificial substrate failed to capture white sturgeon eggs or larvae in 1992. One hundred and four age 1 and 14 age 2 hatchery-reared Kootenai white sturgeon were released into the Idaho section of the river in 1992. Telemetry of six of the larger juveniles showed general downriver movement from September into November.

  10. White Sturgeon Bibliography, 1985 Final Report.

    SciTech Connect

    Fickeisen, Duane H.

    1986-03-01

    This bibliography presents citations to the majority of published materials on white sturgeon (Acipenser transmontanus). The purpose was to assist in planning and implementing research on white sturgeon in the Columbia River system. (ACR)

  11. Kootenai River White Sturgeon Investigations and Experimental Culture, 1988-1989 Annual Report.

    SciTech Connect

    Apperson, Kimberly A.; Anders, Paul J.

    1990-06-01

    The population of white sturgeon in the Kootenai River has continued to decline since 1983, in spite of a closure to harvest in the U.S. section of the river. Setline and angling techniques were used to sample 228 sturgeon from the river between Kootenai Falls and Kootenay Lake during 1989. Sturgeon were found in Montana within 4 km of Kootenai Falls and downstream from Bonners Ferry, Idaho to Kootenay Lake, British Columbia. Our data indicate there is a complete lack of recruitment of juveniles into the population. The youngest fish sampled was of the 1977 year class, and the population is estimated at 850 individuals with 95% confidence intervals of 574 to 1,463. At present, we do not understand what mechanisms are limiting recruitment. Over the past 70 years, the lower Kootenai River has been extensively diked for flood control, effectively eliminating backwater and slough areas that may have provided juvenile rearing habitat: Contaminants have entered the river system via mining operations and agricultural practices. In 1972, Libby Dam began operation, reversing the natural flow regime of the river, and releasing frequent power peaking flows. Of 179 fish that were surgically sexed, 37% were female and 35% were male. Thirty-four percent of the females held developing oocytes. All oocyte samples from nine females contained copper (1.18 to 2.50 {micro}g/g) and zinc (15.6 to 32.8 {micro}g/g). Most samples also contained organochloride residues such as DDT, DDD, DDE, and PCBs (0.215 to 1.080 {micro}g/g, combined). River sediment samples contained 1.62 to 12.8 {micro}g/g copper and 22.4 to 70.6 {micro}g/g zinc, but no organochloride residues. Electrophoretic analysis of muscle samples indicated reduced heterogeneity compared with lower basin white sturgeon and showed a significantly different degree of variation between the two stocks in seven enzyme systems. An ongoing sonic telemetry study has revealed definite long distance movements in response to water flow

  12. White Sturgeon Passage at The Dalles Dam

    USGS Publications Warehouse

    ,

    2008-01-01

    Researchers at the USGS Western Fisheries Research Center's Columbia River Research Laboratory, working with the U.S. Army Corps of Engineers, sought to better understand upstream and downstream passage of white sturgeon at dams. A study at The Dalles Dam provided the opportunity to compare two fish ladders; one that passes sturgeon upstream to one that does not, to determine if subtle differences in construction result in better passage of white sturgeon. Researchers conducted a study using a combination of acoustic and radio telemetry technologies to obtain information on juvenile and adult white sturgeon near The Dalles Dam, with the objectives of characterizing the distribution and movements of white sturgeon in the immediate vicinity of the dam and to determine timing and routes of upstream and downstream passage.

  13. Kootenai River White Sturgeon Investigations and Experimental Culture, 1989-1990 Annual Report.

    SciTech Connect

    Apperson, Kimberly A.; Anders, Paul J.

    1991-10-01

    Setline and angling techniques were used to sample 332 sturgeon from the river between Kootenai Falls and Kootenay Lake during 1989 and 1990. Sturgeon were found in Montana within 4 km of Kootenai Falls and downstream from Bonners Ferry, Idaho to Kootenay Lake, British Columbia. Our data indicate there is a complete lack of recruitment of juveniles into the population. The youngest fish sampled was of the 1977 year class, and the population is estimated at 880 individuals with 95% confidence intervals of 638 to 1,211. Culture of one pair of sturgeon in 1990 was of limited success. Less than 5% of eggs hatched with 50% initial mortality of fry. The contribution of contaminants found in eggs (aluminum, copper, zinc, lead, and organochlorides) toward this poor survival is unknown. Handling problems with the eggs at the time of spawning complicated our results. An ongoing sonic telemetry study has revealed definite long distance movements. Sturgeon regularly move across the British Columbia-Idaho border and seek out deep holes or migrate to Kootenay Lake during late fall. Seasonal differences in use of depth and velocity parameters were found between sexes and among seasons. No relationships were found between sturgeon movement and month, water temperature, flow, and flow change. However, multiple regression analysis indicated that up to 30% of the variance in individual sturgeon movement was explained by the combination of the four variables.

  14. Simulation of Streamflow Using a Multidimensional Flow Model for White Sturgeon Habitat, Kootenai River near Bonners Ferry, Idaho - Supplement to Scientific Investigations Report 2005-5230

    USGS Publications Warehouse

    Barton, Gary J.; McDonald, Richard R.; Nelson, Jonathan M.

    2009-01-01

    During 2005, the U.S. Geological Survey (USGS) developed, calibrated, and validated a multidimensional flow model for simulating streamflow in the white sturgeon spawning habitat of the Kootenai River in Idaho. The model was developed as a tool to aid understanding of the physical factors affecting quality and quantity of spawning and rearing habitat used by the endangered white sturgeon (Acipenser transmontanus) and for assessing the feasibility of various habitat-enhancement scenarios to re-establish recruitment of white sturgeon. At the request of the Kootenai Tribe of Idaho, the USGS extended the two-dimensional flow model developed in 2005 into a braided reach upstream of the current white sturgeon spawning reach. Many scientists consider the braided reach a suitable substrate with adequate streamflow velocities for re-establishing recruitment of white sturgeon. The 2005 model was extended upstream to help assess the feasibility of various strategies to encourage white sturgeon to spawn in the reach. At the request of the Idaho Department of Fish and Game, the USGS also extended the two-dimensional flow model several kilometers downstream of the white sturgeon spawning reach. This modified model can quantify the physical characteristics of a reach that white sturgeon pass through as they swim upstream from Kootenay Lake to the spawning reach. The USGS Multi-Dimensional Surface-Water Modeling System was used for the 2005 modeling effort and for this subsequent modeling effort. This report describes the model applications and limitations, presents the results of a few simple simulations, and demonstrates how the model can be used to link physical characteristics of streamflow to the location of white sturgeon spawning events during 1994-2001. Model simulations also were used to report on the length and percentage of longitudinal profiles that met the minimum criteria during May and June 2006 and 2007 as stipulated in the U.S. Fish and Wildlife Biological Opinion.

  15. Modeling white sturgeon movement in a reservoir: The effect of water quality and sturgeon density

    USGS Publications Warehouse

    Sullivan, A.B.; Jager, H.I.; Myers, R.

    2003-01-01

    We developed a movement model to examine the distribution and survival of white sturgeon (Acipenser transmontanus) in a reservoir subject to large spatial and temporal variation in dissolved oxygen and temperature. Temperature and dissolved oxygen were simulated by a CE-QUAL-W2 model of Brownlee Reservoir, Idaho for a typical wet, normal, and dry hydrologic year. We compared current water quality conditions to scenarios with reduced nutrient inputs to the reservoir. White sturgeon habitat quality was modeled as a function of temperature, dissolved oxygen and, in some cases, suitability for foraging and depth. We assigned a quality index to each cell along the bottom of the reservoir. The model simulated two aspects of daily movement. Advective movement simulated the tendency for animals to move toward areas with high habitat quality, and diffusion simulated density dependent movement away from areas with high sturgeon density in areas with non-lethal habitat conditions. Mortality resulted when sturgeon were unable to leave areas with lethal temperature or dissolved oxygen conditions. Water quality was highest in winter and early spring and lowest in mid to late summer. Limiting nutrient inputs reduced the area of Brownlee Reservoir with lethal conditions for sturgeon and raised the average habitat suitability throughout the reservoir. Without movement, simulated white sturgeon survival ranged between 45 and 89%. Allowing movement raised the predicted survival of sturgeon under all conditions to above 90% as sturgeon avoided areas with low habitat quality. ?? 2003 Elsevier B.V. All rights reserved.

  16. Kootenai River White Sturgeon Studies, Annual Report FY 1993.

    SciTech Connect

    Anders, Paul J.; Siple, John T.

    1993-12-01

    This report evaluates natural spawning of white sturgeon in the Kootenai River before, during and after the 1993 augmented discharge period. To determine how altering the operation of Libby Dam may improve conditions for natural spawning of white sturgeon in the Kootenai River, discharge from Libby Dam (with no power peaking or load following) was increased to produce 20 kcfs ([plus minus] 2 kcfs) discharge at Bonners Ferry, Idaho, for a 14 day period June 2--16. Objectives of this research were to determine if white sturgeon spawned in the Kootenai River during 1993; and collect baseline biological data including timing, location, and habitat requirements of white sturgeon spawning in the Kootenai River in order to formulate and implement future flow regimes as effective recovery measures for white sturgeon. While sampling is not expected to collect a majority of white sturgeon eggs or larvae produced in a river, the fact that over 41,000 hours of sampling (combined gear) collected only 3 white sturgeon eggs and no larvae suggests that spawning conditions during 1993 were inadequate to benefit this population.

  17. The effects of dissolved gas supersaturation on white sturgeon larvae

    USGS Publications Warehouse

    Counihan, T.D.; Miller, A.I.; Mesa, M.G.; Parsley, M.J.

    2000-01-01

    Spill at dams has caused supersaturation of atmospheric gas in waters of the Columbia and Snake rivers and raised concerns about the effects of dissolved gas supersaturation (DGS) on white sturgeons Acipenser transmontanus. The timing and location of white sturgeon spawning and the dispersal of white sturgeon larvae from incubation areas makes the larval stage potentially vulnerable to the effects of DGS. To assess the effects of DGS on white sturgeon larvae, we exposed larvae to mean total dissolved gas (TDG) levels of 118% and 131% saturation in laboratory bioassay tests. Gas bubble trauma (GBT) was manifested as a gas bubble in the buccal cavity, nares, or both and it first occurred at developmental stages characterized by the formation of the mouth and gills. Exposure times of 15 min were sufficient to elicit these signs in larvae in various stages of development. No mortality was observed in larvae exposed to 118% TDG for 10 d, but 50% mortality occurred after a 13-d exposure to 131% TDG. The signs of GBT we observed resulted in positive buoyancy and alterations in behavior that may affect the dispersal and predation vulnerability of white sturgeon larvae. The exact depth distribution of dispersing white sturgeon larvae in the Columbia River currently is unknown. Thus, our results may represent a worst-case scenario if white sturgeon larvae are dispersed at depths with insufficient hydrostatic pressure to compensate for high TDG levels.

  18. Differences in activation of aryl hydrocarbon receptors of white sturgeon relative to lake sturgeon are predicted by identities of key amino acids in the ligand binding domain.

    PubMed

    Doering, Jon A; Farmahin, Reza; Wiseman, Steve; Beitel, Shawn C; Kennedy, Sean W; Giesy, John P; Hecker, Markus

    2015-04-01

    Dioxin-like compounds (DLCs) are pollutants of global environmental concern. DLCs elicit their adverse outcomes through activation of the aryl hydrocarbon receptor (AhR). However, there is limited understanding of the mechanisms that result in differences in sensitivity to DLCs among different species of fishes. Understanding these mechanisms is critical for protection of the diversity of fishes exposed to DLCs, including endangered species. This study investigated specific mechanisms that drive responses of two endangered fishes, white sturgeon (Acipenser transmontanus) and lake sturgeon (Acipenser fulvescens) to DLCs. It determined whether differences in sensitivity to activation of AhRs (AhR1 and AhR2) can be predicted based on identities of key amino acids in the ligand binding domain (LBD). White sturgeon were 3- to 30-fold more sensitive than lake sturgeon to exposure to 5 different DLCs based on activation of AhR2. There were no differences in sensitivity between white sturgeon and lake sturgeon based on activation of AhR1. Adverse outcomes as a result of exposure to DLCs have been shown to be mediated through activation of AhR2, but not AhR1, in all fishes studied to date. This indicates that white sturgeon are likely to have greater sensitivity in vivo relative to lake sturgeon. Homology modeling and in silico mutagenesis suggests that differences in sensitivity to activation of AhR2 result from differences in key amino acids at position 388 in the LBD of AhR2 of white sturgeon (Ala-388) and lake sturgeon (Thr-388). This indicates that identities of key amino acids in the LBD of AhR2 could be predictive of both in vitro activation by DLCs and in vivo sensitivity to DLCs in these, and potentially other, fishes.

  19. Kootenai river velocities, depth, and white sturgeon spawning site selection - A mystery unraveled?

    USGS Publications Warehouse

    Paragamian, V.L.; McDonald, R.; Nelson, G.J.; Barton, G.

    2009-01-01

    The Kootenai River white sturgeon Acipenser transmontanus population in Idaho, US and British Columbia (BC), Canada became recruitment limited shortly after Libby Dam became fully operational on the Kootenai River, Montana, USA in 1974. In the USA the species was listed under the Endangered Species Act in September of 1994. Kootenai River white sturgeon spawn within an 18-km reach in Idaho, river kilometer (rkm) 228.0-246.0. Each autumn and spring Kootenai River white sturgeon follow a 'short two-step' migration from the lower river and Kootenay Lake, BC, to staging reaches downstream of Bonners Ferry, Idaho. Initially, augmented spring flows for white sturgeon spawning were thought to be sufficient to recover the population. Spring discharge mitigation enhanced white sturgeon spawning but a series of research investigations determined that the white sturgeon were spawning over unsuitable incubation and rearing habitat (sand) and that survival of eggs and larvae was negligible. It was not known whether post-Libby Dam management had changed the habitat or if the white sturgeon were not returning to more suitable spawning substrates farther upstream. Fisheries and hydrology researchers made a team effort to determine if the spawning habitat had been changed by Libby Dam operations. Researchers modeled and compared velocities, sediment transport, and bathymetry with post-Libby Dam white sturgeon egg collection locations. Substrate coring studies confirmed cobbles and gravel substrates in most of the spawning locations but that they were buried under a meter or more of post-Libby Dam sediment. Analysis suggested that Kootenai River white sturgeon spawn in areas of highest available velocity and depths over a range of flows. Regardless of the discharge, the locations of accelerating velocities and maximum depth do not change and spawning locations remain consistent. Kootenai River white sturgeon are likely spawning in the same locations as pre-dam, but post-Libby Dam

  20. Vulnerability of young white sturgeon, Acipenser transmontanus, to predation in the presence of alternative prey

    USGS Publications Warehouse

    Gadomski, D.M.; Parsley, M.J.

    2005-01-01

    We conducted laboratory trials to test the vulnerability of young white sturgeon, Acipenser transmontanus, to predation when an alternative prey was available. In trials with two species of predators, we observed two feeding patterns. When equal numbers of white sturgeon and goldfish, Carassius auratus, were available, prickly sculpins, Cottus asper, ingested more white sturgeon. Conversely, northern pikeminnow, Ptychocheilus oregonensis, ate more juvenile coho salmon, Oncorhynchus kisutch, than white sturgeon in three out of four sets of trials, but ate more white sturgeon in one set of trials. White sturgeon size and the availability of cover did not affect the proportions of prey species ingested. Our results indicate that predation may be affecting survival of white sturgeon larvae and juveniles in the wild and could be one factor limiting recruitment of young-of-the-year white sturgeon in some locations. ?? Springer 2005.

  1. Effects of turbidity, light level, and cover on predation of white sturgeon larvae by prickly sculpins

    USGS Publications Warehouse

    Gadomski, D.M.; Parsley, M.J.

    2005-01-01

    White sturgeon Acipenser transmontanus occur in rivers of the western United States and southwestern Canada, but some populations are in decline because of recruitment failure. Many river systems in this area have been altered as a result of development that has caused major environmental changes. Our goal was to examine how three changes - lower turbidity levels, higher light levels, and altered substrates - might affect predation by prickly sculpin Cottus asper on white sturgeon larvae. We experimentally investigated predation at various turbidity levels and found that significantly more white sturgeon yolk sac larvae were eaten at lower turbidity levels. The effects of light level (1-4 and 7-15 1x), the presence or absence of rocks as cover, and prey size (14-17 mm and 20-24 mm total length) on the outcome of predator-prey interactions were also examined. Significantly fewer white sturgeon were eaten during trials that combined the lowest light level, cover, and the smallest larvae. Our results suggest that altered river conditions caused by impoundment and other factors have increased predation on white sturgeon larvae. ?? Copyright by the American Fisheries Society 2005.

  2. Diet of first-feeding larval and young-of-the-year white sturgeon in the lower Columbia River

    USGS Publications Warehouse

    Muir, W.D.; McCabe, G.T.; Parsley, M.J.; Hinton, S.A.

    2000-01-01

    In some Snake and Columbia River reservoirs, adult white sturgeon (Acipenser transmontanus) are common but few juvenile fish are found, indicating a lack of spawning success or poor survival of larvae. In contrast, recruitment of young-of-the-year white sturgeon to juvenile and adult stages is successful in the unimpounded Columbia River downstream of Bonneville Dam. The availability and size of preferred prey during the period when white sturgeon larvae begin exogenous feeding could be an important determinant of year-class strength. To explore this issue, we examined the diet composition of 352 larval and young-of-the year white sturgeon collected from 1989 through 1991 in the lower Columbia River. Samples were collected downstream from Bonneville Dam and upstream from the dam in Bonneville and The Dalles Reservoirs. Fish that ranged in size from 15 to 290 mm in total length fed primarily on gammarid amphipods (Corophium spp.) during all months. This diet item became increasingly important to all sizes of white sturgeon examined as they grew. The length of Corophium spp. eaten by larval and young-of-the-year white sturgeon increased with increasing fish length (r2 = 45.6%, P < 0.0001). Copepods (Cyclopoida), Ceratopogonidae larvae, and Diptera pupae and larvae (primarily chironomids) were also consumed, especially at the onset of exogenous feeding. A small percentage of white sturgeon were found with empty stomachs during June (1.6% downstream from Bonneville Dam) and July (4.5% downstream and 2.6% in the reservoirs). Diets of larval and young-of-the year white sturgeon from both impounded and free-flowing sections of the Columbia River were similar and we found no evidence of larval starvation in the areas investigated, areas currently supporting healthy white sturgeon populations.

  3. Effects of feed restriction on the upper temperature tolerance and heat shock response in juvenile green and white sturgeon.

    PubMed

    Lee, Seunghyung; Hung, Silas S O; Fangue, Nann A; Haller, Liran; Verhille, Christine E; Zhao, Juan; Todgham, Anne E

    2016-08-01

    The objective of the current study was to investigate the effects of feed restriction on whole-organism upper thermal tolerance and the heat shock response of green and white sturgeon to determine how changes in food amount might influence physiological performance of each species when faced with temperature stress. Two parallel feed restriction trials were carried out for juvenile green (202g; 222-day post hatch: dph) and white sturgeon (205g; 197-dph) to manipulate nutritional status at 12.5%, 25%, 50%, or 100% of optimum feeding rate (100% OFR were 1.6% and 1.8% body weight/day, respectively) for four weeks. Following the trials, the critical thermal maximum (CTMax, 0.3°C/min) of sturgeon (N=12/treatment/species) was assessed as an indicator of whole-organism upper thermal tolerance. To assess temperature sensitivity, sturgeon (N=9/treatment/species) were acutely transferred to two temperature treatments (28°C and 18°C as a handling control) for 2h followed by 2h of recovery at 18°C before being sacrificed, and gill, brain, and mucus sampled for measurements of 70-kDa heat shock protein levels (Hsc/Hsp70). Feeding rate had species-specific effects on CTMax in green and white sturgeon such that CTMax of green sturgeon decreased as the magnitude of feed restriction increased; whereas, CTMax of white sturgeon did not change with feed restriction. Elevated temperature (28°C) and feed restriction increased Hsc/Hsp70 levels in the gill tissue of green sturgeon, while heat shock increased Hsc/Hsp70 levels in the mucus of white sturgeon. Our results suggest that green sturgeon may be more susceptible to temperature stress under food-limited conditions.

  4. A comparative gene index for the white sturgeon Acipenser transmontanus.

    PubMed

    Lazzari, Barbara; Mariani, Valentina; Malinverni, Roberto; Caprera, Andrea; Giuffra, Elisabetta

    2008-03-01

    Sturgeons are archaic fishes phylogenetically distinct from Teleosts. They represent an important niche for aquaculture, particularly for the production of caviar and high quality fillets, while many natural populations in various world areas are today threatened by extinction. Knowledge of the sturgeon genome is limited, as it is the case of many other species of interest for fishery, aquaculture and conservation. Sequences from non-normalized libraries of skin and spleen of the American sturgeon (A. transmontanus) produced in our laboratories were analysed via a bioinformatic procedure, and compared to similar resources available for three Teleost species. Data collected during the analyses were stored in a database - the Sturgeon database (db) - that can be queried via a web interface. The Sturgeon db contains a total of 16,404 sequences from Acipenser transmontanus, Ictalurus punctatus, Salmo salar and Takifugu rubripes, each specie being represented by expressed sequence tags (ESTs) from skin and spleen. Data contained in the database are the results of a number of analyses that mostly focus on sequence annotation and intra- and inter-species comparison. Putative SNP sites, tandem repeats, and sequences matching known protein patterns and motifs were also identified. The Sturgeon db is by now the only online resource dedicated to the analysis of A. transmontanus EST sequences, and represents a starting point for the investigation of the genome of sturgeons from a physiological perspective; it will be used to identify polymorphic markers to study, for example, fish pathologies or to survey fish disease resistance, and to produce gene expression arrays. Introduction of sequences from other species in the analysis pipeline allowed inter-species comparisons of transcripts distribution in Gene Ontology categories, as well as orthologs identification, despite the high sturgeon phylogenetic distance from other fish species. As a result of the EST analysis procedure

  5. Toxicity of copper to early-life stage Kootenai River white sturgeon, Columbia River white sturgeon, and rainbow trout

    USGS Publications Warehouse

    Little, E.E.; Calfee, R.D.; Linder, G.

    2012-01-01

    White sturgeon (Acipenser transmontanus) populations throughout western North America are in decline, likely as a result of overharvest, operation of dams, and agricultural and mineral extraction activities in their watersheds. Recruitment failure may reflect the loss of early-life stage fish in spawning areas of the upper Columbia River, which are contaminated with metals from effluents associated with mineral-extraction activities. Early-life stage white sturgeon (A. transmontanus) from the Columbia River and Kootenai River populations were exposed to copper during 96-h flow-through toxicity tests to determine their sensitivity to the metal. Similar tests were conducted with rainbow trout (RBT [Oncorhynchus mykiss]) to assess the comparative sensitivity of this species as a surrogate for white sturgeon. Exposures were conducted with a water quality pH 8.1-8.3, hardness 81-119 mg/L as CaCO2, and dissolved organic carbon 0.2-0.4 mg/L. At approximately 30 days posthatch (dph), sturgeon were highly sensitive to copper with median lethal concentration (LC50) values ranging from 4.1 to 6.8 μg/L compared with 36.5 μg/L for 30 dph RBT. White sturgeon at 123-167 dph were less sensitive to copper with LC50 values ranging from 103.7 to 268.9 μg/L. RBT trout, however, remained more sensitive to copper at 160 dph with an LC50 value of 30.9 μg/L. The results indicate that high sensitivity to copper in early-life stage white sturgeon may be a factor in recruitment failure occurring in the upper Columbia and Kootenai rivers. When site-specific water-quality criteria were estimated using the biotic ligand model (BLM), derived values were not protective of early-life stage fish, nor were estimates derived by water-hardness adjustment.

  6. Can fatty acid and mineral compositions of sturgeon eggs distinguish between farm-raised versus wild white (Acipenser transmontanus) sturgeon origins in California? Preliminary report.

    PubMed

    DePeters, Edward J; Puschner, Birgit; Taylor, Scott J; Rodzen, Jeff A

    2013-06-10

    The objective was to investigate the potential of using fatty acid and mineral compositions of sturgeon eggs to distinguish their source, either farm-raised or wild fish. Trafficking of illegally obtained wild white sturgeon eggs is a major concern to the California Department of Fish and Game, but there is no forensic method to separate wild and farm-raised white sturgeon eggs. The extension of these findings in future work will be to use the fatty acid and mineral compositions as forensic indicators of caviar produced legally from farm raised sturgeon compared with illegal caviar produced from sturgeon poached from the wild. Samples (10) of sturgeon eggs were collected from a commercial aquaculture facility in the Sacramento Valley. Eggs from wild sturgeon (9) were obtained primarily from confiscations of illegally caught sturgeon by fish and game law enforcement personnel. The total lipid content of sturgeon eggs was analyzed for fatty acid composition. The most notable difference was the higher concentration (P<0.001) of C18:2n6 in farm raised eggs (6.5 mg/100g total lipid) than wild eggs (0.6 mg/100g total lipid) while other differences between fatty acids were smaller. Eicosapentaenoic acid (C20:5n3) was higher (P<0.02) in farm-raised (5.56 mg/100g) than wild (4.49 mg/100g). Docosahexaenoic acid (C22:6n3), C18:1 cis 9&10, and C20:4n6 were not different for origin of the eggs. Concentration of selenium was markedly higher (P<0.001) in eggs from wild sturgeon (10.0 mg/kg dry weight) than farm-raised sturgeon (2.7 mg/kg dry weight). Concentrations of iron, zinc, copper, phosphorus, sulfur, calcium, and potassium did not differ between farm-raised and wild eggs. Arsenic concentration in wild eggs was 3.3mg/kg dry weight whereas arsenic was not detected in the farm-raised eggs. Fatty acid and mineral compositions of eggs differed significantly between farm-raised and wild sturgeon and these should be investigated further as biological markers for forensic

  7. First record predation on white sturgeon eggs by sympatric fishes

    USGS Publications Warehouse

    Miller, A.I.; Beckman, L.G.

    1996-01-01

    We report the occurrence of white sturgeon Acipenser transmontanus eggs in guts of four species of fish from the Columbia River. Three of the species—northern squawfish Ptychocheilus oregonensis, largescale sucker Catostomus macrocheilus, and prickly sentpin Cottus asper—are native to the river and one, common carp Cvprinus carpio, is exotic.

  8. Ancient fish and recent invaders: white sturgeon Acipenser transmontanus diet response to invasive-species-mediated changes in a benthic prey assemblage

    USGS Publications Warehouse

    Zeug, Steven C; Brodsky, Annie; Kogut, Nina; Stewart, Robin; Merz, Joe

    2014-01-01

    Invasive organisms can have significant impacts on native species, and the San Francisco Estuary (SFE), California, USA, is one of the world's most invaded estuaries. Decline of native white sturgeon Acipenser transmontanus abundance in the SFE has been acknowledged, but underlying mechanisms are poorly understood. Invasion by the overbite clam Potamocorbula amurensis has drastically altered the SFE benthic prey community, yet little is known about how this change has affected sturgeon diets. We investigated changes in the diet of white sturgeon following the overbite clam invasion and subsequent shift in the SFE benthic prey assemblage. Gut content analysis was used to compare white sturgeon prey composition and importance between the pre- and post-invasion periods. Additionally, stable isotope analysis was employed to estimate the assimilation of prey items to sturgeon biomass. Overbite clams dominated diets in the post-invasion period, accounting for 82 to 93% of total volume. Stable isotope analysis confirmed the importance of this prey item, although their assimilated contribution to sturgeon biomass was estimated to be less (70 to 83%) than gut contents indicated. The frequency of fish in white sturgeon guts increased in the post-invasion period, and isotope analysis indicated relatively large contributions of fish to sturgeon biomass (3.7 to 19%). The trophic adaptability of white sturgeon has allowed them to exploit this new prey source (overbite clam). Future conservation and restoration efforts must consider a potentially destabilized food web given the large importance of a single prey item.

  9. Capture of white sturgeon larvae downstream of The Dalles Dam, Columbia River, Oregon and Washington, 2012

    USGS Publications Warehouse

    Parsley, Michael J.; Kofoot, Eric

    2013-01-01

    Wild-spawned white sturgeon (Acipenser transmontanus) larvae captured and reared in aquaculture facilities and subsequently released, are increasingly being used in sturgeon restoration programs in the Columbia River Basin. A reconnaissance study was conducted to determine where to deploy nets to capture white sturgeon larvae downstream of a known white sturgeon spawning area. As a result of the study, 103 white sturgeon larvae and 5 newly hatched free-swimming embryos were captured at 3 of 5 reconnaissance netting sites. The netting, conducted downstream of The Dalles Dam on the Columbia River during June 25–29, 2012, provided information for potentially implementing full-scale collection efforts of large numbers of larvae for rearing in aquaculture facilities and for subsequent release at a larger size in white sturgeon restoration programs.

  10. Radionuclide concentrations in white sturgeon from the Columbia River

    SciTech Connect

    Dauble, D.D.; Price, K.R.; Poston, T.M.

    1992-09-01

    Although radioactive releases from the US Department of Energy`s Hanford Site have been monitored in the environment since the reactors began operating in 1945, recent information regarding historical releases of radionuclides has led to renewed interest in estimating human exposure to radionuclides at Hanford. Knowledge of the fate of radionuclides in some fish species may be important because of the potential for food-chain transfer to humans. White sturgeon (Acipenser transmontanus) were selected for study because they are long-lived, reside year-round in the Hanford Reach, are benthic, and are an important commercial and sport species in the Columbia River. They also have a greater potential for accumulating persistent radionuclides than shorter-lived species with pelagic and/or anadromous life histories. The purpose of our study was to summarize data on historical concentrations of industrial radionuclides in white sturgeon and to collect additional data on current body burdens in the Columbia River.

  11. Radionuclide concentrations in white sturgeon from the Columbia River

    SciTech Connect

    Dauble, D.D.; Price, K.R.; Poston, T.M.

    1992-09-01

    Although radioactive releases from the US Department of Energy's Hanford Site have been monitored in the environment since the reactors began operating in 1945, recent information regarding historical releases of radionuclides has led to renewed interest in estimating human exposure to radionuclides at Hanford. Knowledge of the fate of radionuclides in some fish species may be important because of the potential for food-chain transfer to humans. White sturgeon (Acipenser transmontanus) were selected for study because they are long-lived, reside year-round in the Hanford Reach, are benthic, and are an important commercial and sport species in the Columbia River. They also have a greater potential for accumulating persistent radionuclides than shorter-lived species with pelagic and/or anadromous life histories. The purpose of our study was to summarize data on historical concentrations of industrial radionuclides in white sturgeon and to collect additional data on current body burdens in the Columbia River.

  12. Lake Roosevelt White Sturgeon Recovery Project : Annual Progress Report, January 2003 – March 2004.

    SciTech Connect

    Howell, Matthew D.; McLellan, Jason G.

    2009-07-15

    This report summarizes catch data collected from white sturgeon Acipenser transmontanus in Lake Roosevelt during limited setlining and gill netting activities in the fall of 2003, and documents progress toward development of a U.S. white sturgeon conservation aquaculture program for Lake Roosevelt. From 27-30 October, 42 overnight small mesh gill net sets were made between Marcus and Northport, WA for a total catch of 15 juvenile white sturgeon (275-488 mm FL). All sturgeon captured were of Canadian hatchery origin. These fish had been previously released as sub-yearlings into the Canadian portion (Keenleyside Reach) of the Transboundary Reach of the Columbia River during 2002 and 2003. Most sturgeon (n=14) were caught in the most upstream area sampled (Northport) in low velocity eddy areas. Five fish exhibited pectoral fin deformities (curled or stunted). Growth rates were less than for juvenile sturgeon captured in the Keenleyside Reach but condition factor was similar. Condition factor was also similar to that observed in juvenile sturgeon (ages 1-8) captured in the unimpounded Columbia River below Bonneville Dam between 1987-92. From 10-14 November, 28 overnight setline sets were made in the Roosevelt Reach between the confluence of the Spokane River and Marcus Island for a total catch of 17 white sturgeon (94-213 cm FL). Catch was greatest in the most upstream areas sampled, a distribution similar to that observed during a WDFW setline survey in Lake Roosevelt in 1998. The mean W{sub r} index of 110% for fish captured this year was higher than the mean W{sub r} of 91% for fish captured in 1998. Excellent fish condition hindered surgical examination of gonads as lipid deposits made the ventral body wall very thick and difficult to penetrate with available otoscope specula. Acoustic tags (Vemco model V16 coded pingers, 69 kHz, 48-month life expectancy) were internally applied to 15 fish for subsequent telemetry investigations of seasonal and reproductively

  13. Effects of feed restriction on salinity tolerance in white sturgeon (Acipenser transmontanus).

    PubMed

    Lee, Seunghyung; Fadel, James G; Haller, Liran Y; Verhille, Christine E; Fangue, Nann A; Hung, Silas S O

    2015-10-01

    A multistressor study was conducted to investigate interactive effects of nutritional status and salinity on osmoregulation of juvenile white sturgeon. Our hypothesis was that lower nutritional status would decrease the salinity tolerance of juvenile white sturgeon. A four-week feed restriction (12.5%, 25%, 50%, 100% of optimum feeding rate: OFR defined as the rate (% body weight per day) at which growth is maximal) trial was performed, and relevant indices of nutritional status were measured. Following the trial, sturgeon were acutely exposed to various salinities (0, 8, 16, 24 ppt) for 120 h, and relevant osmoregulatory measurements were made at 12, 72, and 120 h post-salinity exposures. The feed-restriction trial resulted in a graded nutritional response with the most feed-restricted group (12.5% OFR) showing the lowest nutritional status. The salinity exposure trial showed clear evidence that lower nutritional status decreased the salinity tolerance of juvenile white sturgeon. Increasing salinities resulted in significant alterations in osmoregulatory indices of all feeding groups; however, a significantly slower acclimatory response to 24 ppt was detected in the most feed-restricted group compared to the non-feed-restricted group (100% OFR). Furthermore, evaluation of the effect of nutritional status on the relationship between osmoregulatory measurements and body size showed that there was a significant negative relationship between osmoregulatory performance and body size within the most feed-restricted group. This suggests that there is a certain body size range (200-300 g based on our finding) where juvenile white sturgeon can maximize osmoregulatory capacity at a salinity of 24 ppt. PMID:26123778

  14. Effects of feed restriction on salinity tolerance in white sturgeon (Acipenser transmontanus).

    PubMed

    Lee, Seunghyung; Fadel, James G; Haller, Liran Y; Verhille, Christine E; Fangue, Nann A; Hung, Silas S O

    2015-10-01

    A multistressor study was conducted to investigate interactive effects of nutritional status and salinity on osmoregulation of juvenile white sturgeon. Our hypothesis was that lower nutritional status would decrease the salinity tolerance of juvenile white sturgeon. A four-week feed restriction (12.5%, 25%, 50%, 100% of optimum feeding rate: OFR defined as the rate (% body weight per day) at which growth is maximal) trial was performed, and relevant indices of nutritional status were measured. Following the trial, sturgeon were acutely exposed to various salinities (0, 8, 16, 24 ppt) for 120 h, and relevant osmoregulatory measurements were made at 12, 72, and 120 h post-salinity exposures. The feed-restriction trial resulted in a graded nutritional response with the most feed-restricted group (12.5% OFR) showing the lowest nutritional status. The salinity exposure trial showed clear evidence that lower nutritional status decreased the salinity tolerance of juvenile white sturgeon. Increasing salinities resulted in significant alterations in osmoregulatory indices of all feeding groups; however, a significantly slower acclimatory response to 24 ppt was detected in the most feed-restricted group compared to the non-feed-restricted group (100% OFR). Furthermore, evaluation of the effect of nutritional status on the relationship between osmoregulatory measurements and body size showed that there was a significant negative relationship between osmoregulatory performance and body size within the most feed-restricted group. This suggests that there is a certain body size range (200-300 g based on our finding) where juvenile white sturgeon can maximize osmoregulatory capacity at a salinity of 24 ppt.

  15. Larval green and white sturgeon swimming performance in relation to water-diversion flows.

    PubMed

    Verhille, Christine E; Poletto, Jamilynn B; Cocherell, Dennis E; DeCourten, Bethany; Baird, Sarah; Cech, Joseph J; Fangue, Nann A

    2014-01-01

    Little is known of the swimming capacities of larval sturgeons, despite global population declines in many species due in part to fragmentation of their spawning and rearing habitats by man-made water-diversion structures. Larval green (Acipenser medirostris) and white sturgeon (Acipenser transmontanus) inhabit the highly altered Sacramento-San Joaquin watershed, making them logical species to examine vulnerability to entrainment by altered water flows. The risk of larval sturgeon entrainment is influenced by the ontogeny of swimming capacity and dispersal timing and their interactions with water-diversion structure operations. Therefore, the aim of this study was to describe and compare the ontogeny and allometry of larval green and white sturgeon swimming capacities until completion of metamorphosis into juveniles. Despite the faster growth rates and eventual larger size of larval white sturgeon, green sturgeon critical swimming velocities remained consistently, though modestly, greater than those of white sturgeon throughout the larval life stage. Although behavioural interactions with water-diversion structures are also important considerations, regarding swimming capacity, Sacramento-San Joaquin sturgeons are most vulnerable to entrainment in February-May, when white sturgeon early larvae are in the middle Sacramento River, and April-May, when green sturgeon early larvae are in the upper river. Green sturgeon migrating downstream to the estuary and bays in October-November are also susceptible to entrainment due to their movements combined with seasonal declines in their swimming capacity. An additional inter-species comparison of the allometric relationship between critical swimming velocities and total length with several sturgeon species found throughout the world suggests a similar ontogeny of swimming capacity with growth. Therefore, although dispersal and behaviour differ among river systems and sturgeon species, similar recommendations are applicable

  16. Laboratory studies on the vulnerability of young white sturgeon to predation

    USGS Publications Warehouse

    Gadomski, D.M.; Parsley, M.J.

    2005-01-01

    Despite evidence of annual spawning by white sturgeon Acipenser transmontanus in rivers of the northwestern United States and Canada, in some years and locations little or no recruitment of age-0 white sturgeon has been observed. We examined the vulnerability of white sturgeon larvae and juveniles to predation to further understand possible causes of mortality. We were particularly interested in the vulnerability of older larvae and juveniles because at about 25 mm total length (TL) white sturgeon develop sharp dorsal and lateral scutes that may act as a morphological defense. In the laboratory, white sturgeon ranging from newly hatched larvae to about 170-mm TL juveniles were exposed to predatory fishes they might encounter in the natural environment. We found that channel catfish Ictalurus punctatus (mean TL = 464 mm) and northern pikeminnow Ptychocheilus oregonensis (mean TL = 472 mm) ate white sturgeon up to mean sizes of 121 and 134 mm TL, respectively. Conversely, similarly sized walleyes Sander vitreus ingested almost no white sturgeon, although juvenile walleyes (mean TL = 184 mm) ate white sturgeon up to 59 mm TL. The smallest predator we tested, prickly sculpins Cottus asper (mean TL = 126 mm), ate white sturgeon up to a mean TL of 50 mm. Our study demonstrated that predation is a likely cause of mortality of age-0 white sturgeon and may be contributing to the year-class failures that have been observed. In addition, the results from this study could be used to reduce the predation risk of artificially propagated white sturgeon released to augment declining populations since fish could be reared to sizes where their vulnerability is low.

  17. The elusive minimum viable population size for white sturgeon

    SciTech Connect

    Jager, Yetta; Lepla, Ken B.; Van Winkle, Webb; James, Mr Brad; McAdam, Dr Steve

    2010-01-01

    Biological conservation of sturgeon populations is a concern for many species. Those responsible for managing the white sturgeon (Acipenser transmontanus) and similar species are interested in identifying extinction thresholds to avoid. Two thresholds that exist in theory are the minimum viable population size (MVP) and minimum amount of suitable habitat. In this paper, we present both model and empirical estimates of these thresholds. We modified a population viability analysis (PVA) model for white sturgeon to include two new Allee mechanisms. Despite this, PVA-based MVP estimates were unrealistically low compared with empirical estimates unless opportunities for spawning were assumed to be less frequent. PVA results revealed a trade-off between MVP and habitat thresholds; smaller populations persisted in longer river segments and vice versa. Our empirical analyses suggested (1) a MVP range based on population trends from 1,194 to 27,700 individuals, and (2) a MVP estimate of 4,000 individuals based on recruitment. Long-term historical population surveys are needed for more populations to pinpoint an MVP based on trends, whereas the available data were sufficient to estimate MVP based on recruitment. Beyond the MVP, we developed a hierarchical model for population status based on empirical data. Metapopulation support was the most important predictor of population health, followed by the length of free-flowing habitat, with habitat thresholds at 26 and 150 km. Together, these results suggest that habitat and connectivity are important determinants of population status that likely influence the site-specific MVP thresholds.

  18. Identification of the origin and localization of chorion (egg envelope) proteins in an ancient fish, the white sturgeon, Acipenser transmontanus.

    PubMed

    Murata, Kenji; Conte, Fred S; McInnis, Elizabeth; Fong, Tak Hou; Cherr, Gary N

    2014-06-01

    In many modern teleost fish, chorion (egg envelope) glycoproteins are synthesized in the liver of females, and the expression of those genes is controlled by endogenous estrogen released from the ovary during maturation. However, among the classical teleosts, such as salmonid, carp, and zebrafish, the chorion glycoproteins are synthesized in the oocyte, as in higher vertebrates. Sturgeon, which are members of the subclass Chondrostei, represent an ancient lineage of ray-finned fishes that differ from other teleosts in that their sperm possess acrosomes, their eggs have numerous micropyles, and early embryo development is similar to that of amphibians. In order to understand the molecular mechanisms of chorion formation and the phylogenetic relationship between sturgeon and other teleosts, we used specific antibodies directed against the primary components of sturgeon chorion glycoproteins, using immunoblotting and immunocytochemistry approaches. The origin of each chorion glycoprotein was determined through analyses of both liver and ovary, and their localization during ovarian development was investigated. Our data indicate that the origin of the major chorion glycoproteins of sturgeon, ChG1, ChG2, and ChG4, derive not only from the oocyte itself but also from follicle cells in the ovary, as well as from hepatocytes. In the follicle cell layer, granulosa cells were found to be the primary source of ChGs during oogenesis in white sturgeon. The unique origins of chorion glycoproteins in sturgeon suggest that sturgeons are an intermediate form in the evolution of the teleost lineage.

  19. Identification and response to metals of metallothionein in two ancient fishes: white sturgeon (Acipenser transmontanus) and lake sturgeon (Acipenser fulvescens).

    PubMed

    Doering, Jon A; Beitel, Shawn C; Eisner, Bryanna K; Heide, Timon; Hollert, Henner; Giesy, John P; Hecker, Markus; Wiseman, Steve B

    2015-05-01

    White sturgeon (Acipenser transmontanus) are among the most sensitive species of fishes to Cu, Cd, and Zn, but there is no information about sensitivity of lake sturgeon (Acipenser fulvescens). To begin to elucidate molecular mechanism(s) of sensitivity of sturgeons to metals a cDNA encoding metallothionein (MT) was amplified from livers of white sturgeon (WS-MT) and lake sturgeon (LS-MT), and expression in response to Cu, Cd, or Zn was characterized in liver explants from each species. The primary structure of WS-MT and LS-MT contained 20 cysteine residues, which is the same as MTs of teleost fishes. However, the primary structure of WS-MT and LS-MT contained 63 amino acids, which is longer than any MT identified in teleost fishes. Abundance of transcripts of WS-MT in explants exposed to 0.3, 3, 30, or 100 μg/L of Cu was 1.7-, 1.7-, 2.1-, and 2.6-fold less than in controls, respectively. In contrast, abundances of transcripts of WS-MT were 3.3- and 2.4-fold greater in explants exposed to 30 μg/L of Cd and 1000 μg/L of Zn, respectively. Abundance of transcripts of LS-MT was not significantly different at any concentration of Cu, Cd, or Zn. MT is hypothesized to represent a critical mechanism for detoxification of metals. Therefore, results of this study suggest that sensitivity of sturgeons to exposure to Cu, Cd, or Zn might be a result of the relatively lesser maximal response of MT to metals. The study also suggestslake sturgeon might be more sensitive than white sturgeon to metals.

  20. Identification and response to metals of metallothionein in two ancient fishes: white sturgeon (Acipenser transmontanus) and lake sturgeon (Acipenser fulvescens).

    PubMed

    Doering, Jon A; Beitel, Shawn C; Eisner, Bryanna K; Heide, Timon; Hollert, Henner; Giesy, John P; Hecker, Markus; Wiseman, Steve B

    2015-05-01

    White sturgeon (Acipenser transmontanus) are among the most sensitive species of fishes to Cu, Cd, and Zn, but there is no information about sensitivity of lake sturgeon (Acipenser fulvescens). To begin to elucidate molecular mechanism(s) of sensitivity of sturgeons to metals a cDNA encoding metallothionein (MT) was amplified from livers of white sturgeon (WS-MT) and lake sturgeon (LS-MT), and expression in response to Cu, Cd, or Zn was characterized in liver explants from each species. The primary structure of WS-MT and LS-MT contained 20 cysteine residues, which is the same as MTs of teleost fishes. However, the primary structure of WS-MT and LS-MT contained 63 amino acids, which is longer than any MT identified in teleost fishes. Abundance of transcripts of WS-MT in explants exposed to 0.3, 3, 30, or 100 μg/L of Cu was 1.7-, 1.7-, 2.1-, and 2.6-fold less than in controls, respectively. In contrast, abundances of transcripts of WS-MT were 3.3- and 2.4-fold greater in explants exposed to 30 μg/L of Cd and 1000 μg/L of Zn, respectively. Abundance of transcripts of LS-MT was not significantly different at any concentration of Cu, Cd, or Zn. MT is hypothesized to represent a critical mechanism for detoxification of metals. Therefore, results of this study suggest that sensitivity of sturgeons to exposure to Cu, Cd, or Zn might be a result of the relatively lesser maximal response of MT to metals. The study also suggestslake sturgeon might be more sensitive than white sturgeon to metals. PMID:25795035

  1. Persistence of identifiable remains of white sturgeon juveniles in digestive tracts of northern pikeminnow

    USGS Publications Warehouse

    Gadomski, D.M.; Frost, C.N.

    2004-01-01

    Juvenile white sturgeon, Acipenser transmontanus, have not been commonly identified as prey items in digestive tracts of fishes collected in the wild. In particular, the diet of northern pikeminnow, Ptychocheilus oregonensis, an abundant Pacific Northwest freshwater predator which has been widely studied, has not included juvenile white sturgeon. To aid in interpreting these results and help in planning future feeding studies, we determined the persistence of identifiable remains of white sturgeon juveniles in this predator's digestive tract. Northern pikeminnow (mean total length = 476 mm), were force-fed meals of 2 or 3 juvenile white sturgeon (mean total length = 91 mm). After digestive periods of 4, 8, 16, 24, 28, and 32h at a water temperature of about 17 ??C, fish were sacrificed, digestive tracts removed, and contents examined. Our results indicate that juvenile white sturgeon would be readily discernable in digestive tracts of northern pikeminnow at least a day after feeding, with scutes remaining undigested and identifiable for 28 h.

  2. Effect of dietary selenomethionine on growth performance, tissue burden, and histopathology in green and white sturgeon.

    PubMed

    De Riu, Nicola; Lee, Jang-Won; Huang, Susie S Y; Moniello, Giuseppe; Hung, Silas S O

    2014-03-01

    A comparative examination of potential differences in selenium (Se) sensitivity was conducted on two sturgeon species indigenous to the San Francisco Bay-Delta. Juvenile green (Acipenser medirostris), recently given a federally threatened status, and white sturgeon (Acipenser transmontanus) were exposed to one of four nominal concentrations of dietary l-selenomethionine (SeMet) (0 (control), 50, 100, or 200 mg SeMet/kg diet) for 8 weeks. Mortality, growth performance, whole body composition, histopathology, and Se burdens of the whole body, liver, kidneys, gills, heart, and white muscle were determined every 2 to 4 weeks. Significant (p<0.05) mortality was observed in green sturgeon fed the highest SeMet diet after 2 weeks, whereas no mortality was observed in white sturgeon. Growth rates were significantly reduced in both species; however, green sturgeon was more adversely affected by the treatment. Dietary SeMet significantly affected whole body composition and most noticeably, in the decline of lipid contents in green sturgeon. Selenium accumulated significantly in all tissues relative to the control groups. After 4 and 8 weeks of exposure, marked abnormalities were observed in the kidneys and liver of both sturgeon species; however, green sturgeon was more susceptible to SeMet than white sturgeon at all dietary SeMet levels. Our results showed that a dietary Se concentration at 19.7 ± 0.6 mg Se/kg, which is in range with the reported Se concentrations of the benthic macro-vertebrate community of the San Francisco Bay, had adverse effects on both sturgeon species. However, the exposure had a more severe pathological effect on green sturgeon, suggesting that when implementing conservation measures, this federally listed threatened species should be monitored and managed independently from white sturgeon.

  3. Radionuclide concentrations in white sturgeon from the Columbia River. Revision 1

    SciTech Connect

    Dauble, D.D.; Price, K.R.; Poston, T.M.

    1993-11-01

    The objectives of this study were to (1) review and summarize historical data on radionuclide concentrations in white sturgeon from the Columbia River, (2) determine present-day radionuclide tissue burdens from different locations in the Columbia River, and (3) compare historical data with current data. We first reviewed and summarized the historical literature on radionuclide concentrations in white sturgeon from the Hanford Reach. Field studies were then conducted to evaluate the relationship among sample locations, age/length of white sturgeon, and present radionuclide tissue burdens. Results and comparisons are discussed in the remainder of this report.

  4. Influence of externally attached trasmitters on the swimming performance of juvenile white sturgeon

    USGS Publications Warehouse

    Counihan, T.D.; Frost, C.N.

    1999-01-01

    We measured the critical swimming speed of juvenile white sturgeons Acipenser transmontanus equipped with externally attached dummy ultrasonic transmitters and of untagged control fish in the laboratory. White sturgeons ranging from 31.9 to 37.0 cm fork length were subjected to one of three treatments: Control (handled but not tagged), tag attached below the dorsal fin, and tag attached with the anterior insertion point between the fourth and fifth dorsal scutes. Although transmitters were of recommended weight, we found that the swimming performance of tagged white sturgeons was significantly less than that of untagged control fish. Swimming performance of tagged fish was not differentially affected by tag location. Our results suggest that data from ultrasonic telemetry studies of externally tagged juvenile white sturgeons should be interpreted with caution due to the reduced swimming performance caused by external transmitters.

  5. Influence of externally attached transmitters on the swimming performance of juvenile white sturgeon

    USGS Publications Warehouse

    Counihan, T.D.; Frost, C.N.

    1999-01-01

    We measured the critical swimming speed of juvenile white sturgeons Acipenser transmontanus equipped with externally attached dummy ultrasonic transmitters and of untagged control fish in the laboratory. White sturgeons ranging from 31.9 to 37.0 cm fork length were subjected to one of three treatments: control (handled but not tagged), tag attached below the dorsal fin, and tag attached with the anterior insertion point between the fourth and fifth dorsal scutes. Although transmitters were of recommended weight, we found that the swimming performance of tagged white sturgeons was significantly less than that of untagged control fish. Swimming performance of tagged fish was not differentially affected by tag location. Our results suggest that data from ultrasonic telemetry studies of externally tagged juvenile white sturgeons should be interpreted with caution due to the reduced swimming performance caused by external transmitters.

  6. Physiological stress response, reflex impairment and delayed mortality of white sturgeon Acipenser transmontanus exposed to simulated fisheries stressors

    PubMed Central

    McLean, Montana F.; Hanson, Kyle C.; Cooke, Steven J.; Hinch, Scott G.; Patterson, David A.; Nettles, Taylor L.; Litvak, Matt K.; Crossin, Glenn T.

    2016-01-01

    White sturgeon (Acipenser transmontanus) are the largest freshwater fish in North America and a species exposed to widespread fishing pressure. Despite the growing interest in recreational fishing for white sturgeon, little is known about the sublethal and lethal impacts of angling on released sturgeon. In summer (July 2014, mean water temperature 15.3°C) and winter (February 2015, mean water temperature 6.6°C), captive white sturgeon (n = 48) were exposed to a combination of exercise and air exposure as a method of simulating an angling event. After the stressor, sturgeon were assessed for a physiological stress response, and reflex impairments were quantified to determine overall fish vitality (i.e. capacity for survival). A physiological stress response occurred in all sturgeon exposed to a fishing-related stressor, with the magnitude of the response correlated with the duration of the stressor. Moreover, the stress from exercise was more pronounced in summer, leading to higher reflex impairment scores (mean ± SEM, 0.44 ± 0.07 and 0.25 ± 0.05 in summer and winter, respectively). Reflex impairment was also correlated with lactate concentrations (e.g. physiological stress measures related to exhaustive exercise; r = 0.53) and recovery time (r = 0.76). Two mortalities occurred >24 h after the cessation of treatment in the summer. Given that natural habitats for white sturgeon can reach much higher temperatures than those presented in our study, we caution the use of this mortality estimate for a summer season, because latent mortality could be much higher when temperatures exceed 16°C. This is the first experiment investigating the physiological disturbance and reflex impairment of capture and release at two temperatures on subadult/adult white sturgeon, and the results suggest that future research needs to examine the longer term and fitness consequences of extended play and air exposure times, because these are largely unknown for wild populations

  7. White sturgeon spawning areas in the lower Snake River

    USGS Publications Warehouse

    Parsley, M.J.; Kappenman, K.M.

    2000-01-01

    We documented 17 white sturgeon Acipenser transmontanus spawning locations in the Snake River from the mouth to Lower Granite Dam (river km 0 to 173). Spawning locations were determined by the collection of fertilized eggs on artificial substrates or in plankton nets. We collected 245 eggs at seven locations in McNary Reservoir, 22 eggs at three locations in Ice Harbor Reservoir, 30 eggs from two locations in Lower Monumental Reservoir, and 464 eggs at five locations in Little Goose Reservoir. All 17 locations were in high water velocity areas and between 1.0 and 7.0 km downstream from a hydroelectric dam. The documentation of spawning areas is important because this habitat is necessary to maintain natural and viable populations.

  8. Kootenai River White Sturgeon Conservation Aquaculture Project : Environmental Assessment.

    SciTech Connect

    US Bonneville Power Administration; Kootenai Tribe of Idaho

    1997-04-01

    Bonneville Power Administration (BPA) is responding to the need to prevent the extinction of the Kootenai River white sturgeon (Acipenser transmontanus) between Libby Dam in Montana and Corra Linn Dam in British Columbia. Construction and operation of Libby Dam altered the natural flow of the Kootenai River, especially the normal May-to-July flows needed for natural reproduction and recruitment. It also affected the river`s biological productivity and the quality of spawning and rearing habitat. As part of its responsibilities under the Northwest Power Act (Pacific Northwest Electric Power Planning and Conservation Act of 1980), BPA must mitigate for losses of fish and wildlife (including related spawning grounds and habitat) that are attributable to power production at federal hydroelectric dams on the Columbia River and its tributaries.

  9. A spatial model of white sturgeon rearing habitat in the lower Columbia River, USA

    USGS Publications Warehouse

    Hatten, J.R.; Parsley, M.J.

    2009-01-01

    Concerns over the potential effects of in-water placement of dredged materials prompted us to develop a GIS-based model that characterizes in a spatially explicit manner white sturgeon Acipenser transmontanus rearing habitat in the lower Columbia River, USA. The spatial model was developed using water depth, riverbed slope and roughness, fish positions collected in 2002, and Mahalanobis distance (D2). We created a habitat suitability map by identifying a Mahalanobis distance under which >50% of white sturgeon locations occurred in 2002 (i.e., high-probability habitat). White sturgeon preferred relatively moderate to high water depths, and low to moderate riverbed slope and roughness values. The eigenvectors indicated that riverbed slope and roughness were slightly more important than water depth, but all three variables were important. We estimated the impacts that fill might have on sturgeon habitat by simulating the addition of fill to the thalweg, in 3-m increments, and recomputing Mahalanobis distances. Channel filling simulations revealed that up to 9 m of fill would have little impact on high-probability habitat, but 12 and 15 m of fill resulted in habitat declines of ???12% and ???45%, respectively. This is the first spatially explicit predictive model of white sturgeon rearing habitat in the lower Columbia River, and the first to quantitatively predict the impacts of dredging operations on sturgeon habitat. Future research should consider whether water velocity improves the accuracy and specificity of the model, and to assess its applicability to other areas in the Columbia River.

  10. Diel and seasonal movements of white sturgeon, Acipenser transmontanus, in the mid-Columbia river

    SciTech Connect

    Haynes, J.M.; Gray, R.H.

    1981-04-01

    To evaluate seasonal movements in the free-flowing Hanford reach of the Columbia River, white sturgeon with radio transmitters in spring and early summer 1977 were monitored along with fish that had been tagged in 1975 and 1976. Daily environmental temperature records indicated sturgeon did not consistently engage in a diel movement pattern. It was concluded that although temperature is a major influence stimulating seasonal movements, light cycle and feeding probably influence diel movements. (JMT)

  11. Snout dimorphism in white sturgeon, Acipenser transmontanus, from the Columbia River at Hanford, Washington

    SciTech Connect

    Crass, D.W.; Gray, R.H.

    1982-01-01

    Although differences in snout length and shape between young and adult sturgeon are known, morphological divergence in snout type of similar sized individuals has not been reported. Field observations in the Hanford reach of the Columbia River on 99 white sturgeon ranging from 35 to 205 cm total length showed two snout types based on size and shape. The occurrence of this dimorphism at Hanford may reflect isolating mechanisms, such as physical barriers which block fish movements. (RAF)

  12. Humoral immunoglobulins of the white sturgeon, Acipenser transmontanus: partial characterization of and recognition with monoclonal antibodies.

    PubMed

    Adkison, M A; Basurco, B; Hedrick, R P

    1996-01-01

    White sturgeon (Acipenser transmontanus) immunoglobulin (Ig) was purified from serum by two methods, ion-exchange chromatography and gel filtration and precipitation of the euglobulin fraction. The purity of these immunoglobulin preparations was confirmed by gel electrophoresis. Sequence analysis of the N-terminal amino acids confirmed that the purified protein was immunoglobulin. The major portion of the immunoglobulin preparation consisted of two proteins with estimated molecular weights (m.w.) of 870 and 170 kDa. The m.w. of the H- and L-chains of the purified Ig were 73 and 27-30 kDa, respectively, as determined by SDS-PAGE. Ion-exchange purified Ig was used to immunize mice for the production of monoclonal antibodies. This resulted in the production of six stable hybrids that recognized sturgeon Ig, two specific for heavy chain and four specific for light chain. The two anti-H-chain mabs were highly specific for white sturgeon Ig while all four anti-L-chain mabs cross reacted with Ig from green sturgeon (A. medirostris), Atlantic sturgeon (A. oxyrhynchus oxyrhynchus), shovelnose sturgeon (Scaphirhynchus platorynchus), and paddlefish (Polyodon spathula), (all Chondrosteans), but not with channel catfish (Ictalurus punctatus), rainbow trout (Oncorhynchus mykiss) or striped bass (Morone saxatilis). The mabs were used to enumerate the percentage of sIg+ lymphocytes in the peripheral blood of white sturgeon by flow cytometry. The percentage of cells positively stained with the mabs ranged from 12 to 28%. In a comparison of mabs with polyclonal rabbit anti-sturgeon Ig serum by ELISA the mabs produced a larger signal and less background than the polyclonal serum.

  13. Seasonal and diel movements of white sturgeon in the lower columbia river

    USGS Publications Warehouse

    Parsley, M.J.; Popoff, N.D.; Van Der Leeuw, B. K.; Wright, C.D.

    2008-01-01

    Continuous monitoring of the movements and depths used by white sturgeon Acipenser transmontanus with acoustic telemetry technologies in the lower Columbia River provided information on diel and seasonal migrations, local movements, and site fidelity. White sturgeon moved to shallower water at night and showed greater activity, inferred from rates of movement, than during daytime. The extent of local movement within a season was variable among fish; some fish readily moved among habitats while the movements of others were more constrained. White sturgeon were absent from the study area (river kilometers 45-52) during winter and returned from upstream during the spring, confirming an upstream seasonal migration in the fall and downstream migration in spring. The return of individual fish and reoccupation of areas previously inhabited showed that some white sturgeon exhibit site fidelity. This work shows that studies seeking to characterize habitat for white sturgeon need to be cognizant of diel migrations and site fidelity. We urge caution in the use of limited fish location data to describe habitats if diel activities and fine-scale movements are not known.

  14. White Sturgeon Mitigation and Restoration in the Columbia and Snake Rivers Upstream from Bonneville Dam; 2001-2002 Annual Report.

    SciTech Connect

    Ward, David L.; Kern, J. Chris; Hughes, Michele L.

    2003-12-01

    We report on our progress from April 2001 through March 2002 on determining the effects of mitigative measures on productivity of white sturgeon populations in the Columbia River downstream from McNary Dam, and on determining the status and habitat requirements of white sturgeon populations in the Columbia and Snake rivers upstream from McNary Dam.

  15. White Sturgeon Mitigation and Restoration in the Columbia and Snake Rivers Upstream from Bonneville Dam; 2002-2003 Annual Report.

    SciTech Connect

    Ward, David L.; Kern, J. Chris; Hughes, Michele L.

    2004-02-01

    We report on our progress from April 2002 through March 2003 on determining the effects of mitigative measures on productivity of white sturgeon populations in the Columbia River downstream from McNary Dam, and on determining the status and habitat requirements of white sturgeon populations in the Columbia and Snake rivers upstream from McNary Dam.

  16. Functionality of aryl hydrocarbon receptors (AhR1 and AhR2) of white sturgeon (Acipenser transmontanus) and implications for the risk assessment of dioxin-like compounds.

    PubMed

    Doering, Jon A; Farmahin, Reza; Wiseman, Steve; Kennedy, Sean W; Giesy, John P; Hecker, Markus

    2014-07-15

    Worldwide, populations of sturgeons are endangered, and it is hypothesized that anthropogenic chemicals, including dioxin-like compounds (DLCs), might be contributing to the observed declines in populations. DLCs elicit their toxic action through activation of the aryl hydrocarbon receptor (AhR), which is believed to regulate most, if not all, adverse effects associated with exposure to these chemicals. Currently, risk assessment of DLCs in fishes uses toxic equivalency factors (TEFs) developed for the World Health Organization (WHO) that are based on studies of embryo-lethality with salmonids. However, there is a lack of knowledge of the sensitivity of sturgeons to DLCs, and it is uncertain whether TEFs developed by the WHO are protective of these fishes. Sturgeons are evolutionarily distinct from salmonids, and the AhRs of sturgeons differ from those of salmonids. Therefore, this study investigated the sensitivity of white sturgeon (Acipenser transmontanus) to DLCs in vitro via the use of luciferase reporter gene assays using COS-7 cells transfected with AhR1 or AhR2 of white sturgeon. Specifically, activation and relative potencies (RePs) of 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD), 2,3,4,7,8-pentachloro-dibenzofuran, 2,3,7,8-tetrachloro-dibenzofuran, 3,3',4,4',5-pentachlorobiphenyl, 3,3',4,4'-tetrachlorobiphenyl, and 2,3,3',4,4'-pentachlorobiphenyl were determined for each AhR. It was demonstrated that white sturgeon expresses AhR1s and AhR2s that are both activated by DLCs with EC50 values for 2,3,7,8-TCDD that are lower than those of any other AhR of vertebrates tested to date. Both AhRs of white sturgeon had RePs for polychlorinated dibenzofurans more similar to TEFs for birds, while RePs for polychlorinated biphenyls were most similar to TEFs for fishes. Measured concentrations of select DLCs in tissues of white sturgeon from British Columbia, Canada, were used to calculate toxic equivalents (TEQs) by use of TEFs for fishes used by the WHO and TCDD

  17. Movements of White Sturgeon in Lake Roosevelt : Final Report 1988-1991.

    SciTech Connect

    Brannon, E.L.; Setter, Ann L.

    1992-06-01

    Historically, white sturgeon moved throughout the Columbia River system, ranging freely from the estuary to the headwaters, with the possible exception of limited passage at Cascades, Celilo and Kettle Falls during spring floods. Construction of Rock Island Dam in 1933, followed by Bonneville in 1938 and Grand Coulee in 1941, completely disrupted sturgeon migratory opportunity, and with the 17 successive Columbia and Snake river dams constructed over the next 32 years an entirely different river system was created for the species. Sturgeon caught between dams were essentially isolated populations with severely limited reproduction potential. Some reservoirs ran from dam to dam with no river habitat remaining, while other reaches had various lengths of free running river, but drastically reduced from historical situations. However, if reservoirs provide habitat for sturgeon use, and therefore compensate to some degree for river loss, the major limiting factors associated with population viability may be reduced spawning success, either from lack of suitable area or poor incubation environments. The most upstream impoundment of the Columbia River in the United States is Lake Roosevelt, behind Grand Coulee Dam. If sturgeon don`t use Lake Roosevelt the capacity of the system to sustain a large sturgeon population would be understandably limited, and much reduced from the pre-dam era. In general this study found that sturgeon spawner aggregations from early spring to mid- summer depend most heavily on the timing of increasing water temperature. In the spring the water temperatures seem to stimulate the fish to start feeding and leave deep pools. The summer provides access to broader and shallower areas for food. The study on sturgeon movement was an attempt to define habitat use in such a reservoir/river system.

  18. Is hepatic oxidative stress a main driver of dietary selenium toxicity in white sturgeon (Acipenser transmontanus)?

    PubMed

    Zee, Jenna; Patterson, Sarah; Wiseman, Steve; Hecker, Markus

    2016-11-01

    Most species of sturgeon have experienced significant population declines and poor recruitment over the past decades, leading many, including white sturgeon (Acipenser transmontanus), to be listed as endangered. Reasons for these declines are not yet fully understood but benthic lifestyle, longevity, and delayed sexual maturation likely render sturgeon particularly susceptible to factors such as habitat alteration and contaminant exposures. One contaminant of particular concern to white sturgeon is selenium (Se), especially in its more bioavailable form selenomethionine (SeMet), as it is known to efficiently bioaccumulate in prey items of this species. Studies have shown white sturgeon to be among the most sensitive species of fish to dietary SeMet as well as other pollutants such as metals, dioxin-like chemicals and endocrine disrupters. One of the primary hypothesized mechanisms of toxicity of SeMet in fish is oxidative stress; however, little is know about the specific mode by which SeMet affects the health of white sturgeon. Therefore, the aim of this study was to characterize oxidative stress and associated antioxidant responses as a molecular event of toxicity, and to link it with the pathological effects observed previously. Specifically, three-year-old white sturgeon were exposed for 72 days via their diet to 1.4, 5.6, 22.4 or 104.4µg Se per g feed (dm). Doses were chosen to range over a necessary Se intake level, current environmentally relevant intakes and an intake representing predicted increases of Se release. Lipid hydroperoxides, which are end products of lipid oxidation, were quantified as a marker of oxidative stress. Changes in gene expression of glutathione peroxidase (GPx), superoxide dismutase, catalase, glutathione S-transferase, apoptosis inducing factor and caspase 3 were quantified as markers of the response to oxidative stress. Concentrations of lipid hydroperoxides were highly variable within dose groups and no dose response was observed

  19. Is hepatic oxidative stress a main driver of dietary selenium toxicity in white sturgeon (Acipenser transmontanus)?

    PubMed

    Zee, Jenna; Patterson, Sarah; Wiseman, Steve; Hecker, Markus

    2016-11-01

    Most species of sturgeon have experienced significant population declines and poor recruitment over the past decades, leading many, including white sturgeon (Acipenser transmontanus), to be listed as endangered. Reasons for these declines are not yet fully understood but benthic lifestyle, longevity, and delayed sexual maturation likely render sturgeon particularly susceptible to factors such as habitat alteration and contaminant exposures. One contaminant of particular concern to white sturgeon is selenium (Se), especially in its more bioavailable form selenomethionine (SeMet), as it is known to efficiently bioaccumulate in prey items of this species. Studies have shown white sturgeon to be among the most sensitive species of fish to dietary SeMet as well as other pollutants such as metals, dioxin-like chemicals and endocrine disrupters. One of the primary hypothesized mechanisms of toxicity of SeMet in fish is oxidative stress; however, little is know about the specific mode by which SeMet affects the health of white sturgeon. Therefore, the aim of this study was to characterize oxidative stress and associated antioxidant responses as a molecular event of toxicity, and to link it with the pathological effects observed previously. Specifically, three-year-old white sturgeon were exposed for 72 days via their diet to 1.4, 5.6, 22.4 or 104.4µg Se per g feed (dm). Doses were chosen to range over a necessary Se intake level, current environmentally relevant intakes and an intake representing predicted increases of Se release. Lipid hydroperoxides, which are end products of lipid oxidation, were quantified as a marker of oxidative stress. Changes in gene expression of glutathione peroxidase (GPx), superoxide dismutase, catalase, glutathione S-transferase, apoptosis inducing factor and caspase 3 were quantified as markers of the response to oxidative stress. Concentrations of lipid hydroperoxides were highly variable within dose groups and no dose response was observed

  20. Linking Oxidative Stress and Magnitude of Compensatory Responses with Life-Stage Specific Differences in Sensitivity of White Sturgeon (Acipenser transmontanus) to Copper or Cadmium.

    PubMed

    Tang, Song; Doering, Jon A; Sun, Jianxian; Beitel, Shawn C; Shekh, Kamran; Patterson, Sarah; Crawford, Sarah; Giesy, John P; Wiseman, Steve B; Hecker, Markus

    2016-09-01

    Sensitivity of white sturgeon (Acipenser transmontanus) to copper (Cu) or cadmium (Cd) has been shown to significantly differ as a function of life-stage. This study investigated oxidative stress, metal homeostasis, and associated compensatory responses as potential mechanisms of this sensitivity pattern in three early life-stages. Sturgeon were most sensitive to Cu at 15 days post hatch (dph), which was accompanied by a significant increase in lipid peroxidation (LPO). Genes involved with amelioration of oxidative stress were significantly less inducible at this stage than in older, less sensitive fry. At 48 dph, acute lethality of sturgeon exposed to Cd was greatest and body LPO was significantly induced by 3.5-fold at 5 μg Cd/L. Moreover, there was a small but significant increase in antioxidative responses. At 139 dph, sturgeon were most tolerant to Cu and Cd and accumulation of these metals was least. Also, expression of metallothionein (MT) and apoptotic genes were greatest while expression of metal transporters was reduced and concentration of LPO was not different from controls. Our results suggest that life-stage specific sensitivity of white sturgeon to metals is complex, encompassing differences in the ability to mount compensatory responses important for metal homeostasis and combating oxidative stress and concomitant damages. PMID:27509013

  1. Linking Oxidative Stress and Magnitude of Compensatory Responses with Life-Stage Specific Differences in Sensitivity of White Sturgeon (Acipenser transmontanus) to Copper or Cadmium.

    PubMed

    Tang, Song; Doering, Jon A; Sun, Jianxian; Beitel, Shawn C; Shekh, Kamran; Patterson, Sarah; Crawford, Sarah; Giesy, John P; Wiseman, Steve B; Hecker, Markus

    2016-09-01

    Sensitivity of white sturgeon (Acipenser transmontanus) to copper (Cu) or cadmium (Cd) has been shown to significantly differ as a function of life-stage. This study investigated oxidative stress, metal homeostasis, and associated compensatory responses as potential mechanisms of this sensitivity pattern in three early life-stages. Sturgeon were most sensitive to Cu at 15 days post hatch (dph), which was accompanied by a significant increase in lipid peroxidation (LPO). Genes involved with amelioration of oxidative stress were significantly less inducible at this stage than in older, less sensitive fry. At 48 dph, acute lethality of sturgeon exposed to Cd was greatest and body LPO was significantly induced by 3.5-fold at 5 μg Cd/L. Moreover, there was a small but significant increase in antioxidative responses. At 139 dph, sturgeon were most tolerant to Cu and Cd and accumulation of these metals was least. Also, expression of metallothionein (MT) and apoptotic genes were greatest while expression of metal transporters was reduced and concentration of LPO was not different from controls. Our results suggest that life-stage specific sensitivity of white sturgeon to metals is complex, encompassing differences in the ability to mount compensatory responses important for metal homeostasis and combating oxidative stress and concomitant damages.

  2. Adverse health effects and histological changes in white sturgeon (Acipenser transmontanus) exposed to dietary selenomethionine.

    PubMed

    Zee, Jenna; Patterson, Sarah; Gagnon, Danielle; Hecker, Markus

    2016-07-01

    It has been shown that selenium (Se) released to the aquatic environment can have devastating effects on local wildlife. White sturgeon (Acipenser transmontanus) have a life history particularly susceptible to contaminants, and their protection is of interest as they are culturally and economically important, and many populations are classified as endangered. During the present 72-d dietary study, multiple signs of decreased health and Se lethality were observed. Juvenile white sturgeon were given diets containing 1.4 μg, 5.6 μg, 22.4 μg, or 104.4 μg selenomethionine/g food (dry mass). Selenium accumulated in muscle and liver tissue in a dose-dependent manner. Edema causing exophthalmos developed within 15 d and 23 d, and lethal effects occurred in 54% and 22% of fish in the high- and medium-dose groups, respectively. Growth and hepatosomatic index were significantly lower in the high-dose group, which also had a high incidence of food avoidance. Histology of the liver revealed a dose-dependent increase in melanomacrophage aggregates and decrease of energy stores, which indicated toxicity. These results indicate that white sturgeon are susceptible to the effects of Se accumulation over relatively short time periods. This stresses the need for continued sturgeon research and studies looking into the environmental fate and regulation of released Se. Environ Toxicol Chem 2016;35:1741-1750. © 2015 SETAC. PMID:26632643

  3. Adverse health effects and histological changes in white sturgeon (Acipenser transmontanus) exposed to dietary selenomethionine.

    PubMed

    Zee, Jenna; Patterson, Sarah; Gagnon, Danielle; Hecker, Markus

    2016-07-01

    It has been shown that selenium (Se) released to the aquatic environment can have devastating effects on local wildlife. White sturgeon (Acipenser transmontanus) have a life history particularly susceptible to contaminants, and their protection is of interest as they are culturally and economically important, and many populations are classified as endangered. During the present 72-d dietary study, multiple signs of decreased health and Se lethality were observed. Juvenile white sturgeon were given diets containing 1.4 μg, 5.6 μg, 22.4 μg, or 104.4 μg selenomethionine/g food (dry mass). Selenium accumulated in muscle and liver tissue in a dose-dependent manner. Edema causing exophthalmos developed within 15 d and 23 d, and lethal effects occurred in 54% and 22% of fish in the high- and medium-dose groups, respectively. Growth and hepatosomatic index were significantly lower in the high-dose group, which also had a high incidence of food avoidance. Histology of the liver revealed a dose-dependent increase in melanomacrophage aggregates and decrease of energy stores, which indicated toxicity. These results indicate that white sturgeon are susceptible to the effects of Se accumulation over relatively short time periods. This stresses the need for continued sturgeon research and studies looking into the environmental fate and regulation of released Se. Environ Toxicol Chem 2016;35:1741-1750. © 2015 SETAC.

  4. Impact of Nutrition and Salinity Changes on Biological Performances of Green and White Sturgeon

    PubMed Central

    Vaz, Pedro G.; Kebreab, Ermias; Hung, Silas S. O.; Fadel, James G.; Lee, Seunghyung; Fangue, Nann A.

    2015-01-01

    Green and white sturgeon are species of high conservational and economic interest, particularly in the San Francisco Bay Delta (SFBD) for which significant climate change-derived alterations in salinity and nutritional patterns are forecasted. Although there is paucity of information, it is critical to test the network of biological responses underlying the capacity of animals to tolerate current environmental changes. Through nutrition and salinity challenges, climate change will likely have more physiological effect on young sturgeon stages, which in turn may affect growth performance. In this study, the two species were challenged in a multiple-factor experimental setting, first to levels of feeding rate, and then to salinity levels for different time periods. Data analysis included generalized additive models to select predictors of growth performance (measured by condition factor) among the environmental stressors considered and a suite of physiological variables. Using structural equation modeling, a path diagram is proposed to quantify the main linkages among nutrition status, salinity, osmoregulation variables, and growth performances. Three major trends were anticipated for the growth performance of green and white sturgeon in the juvenile stage in the SFBD: (i) a decrease in prey abundance will be highly detrimental for the growth of both species; (ii) an acute increase in salinity within the limits studied can be tolerated by both species but possibly the energy spent in osmoregulation may affect green sturgeon growth within the time window assessed; (iii) the mechanism of synergistic effects of nutrition and salinity changes will be more complex in green sturgeon, with condition factor responding nonlinearly to interactions of salinity and nutrition status or time of salinity exposure. Green sturgeon merits special scientific attention and conservation effort to offset the effects of feed restriction and salinity as key environmental stressors in the

  5. A proteomic analysis of green and white sturgeon larvae exposed to heat stress and selenium

    PubMed Central

    Silvestre, Frédéric; Linares-Casenave, Javier; Doroshov, Serge I.; Kültz, Dietmar

    2012-01-01

    Temperature and selenium are two environmental parameters that potentially affect reproduction and stock recruitment of sturgeon in the San Francisco Bay / Delta Estuary. To identify proteins whose expression is modified by these environmental stressors, we performed a proteomic analysis on larval green and white sturgeons exposed to 18 or 26°C and micro-injected with Seleno-L-Methionine to reach 8 μg g-1 selenium body burden, with L-Methionine as a control. Selenium and high temperature induced mortalities and abnormal morphologies in both species, with a higher mortality in green sturgeon. Larval proteins were separated by two-dimensional gel electrophoresis and differential abundances were detected following spot quantitation and hierarchical cluster analysis. In green sturgeon, 34 of 551 protein spots detected on gels showed a variation in abundance whereas in white sturgeon only 9 of 580 protein spots were differentially expressed (P<0.01). Gel replicates were first grouped according to heat treatment. Fifteen of these spots were identified using MALDI TOF/TOF mass spectrometry. Proteins involved in protein folding, protein synthesis, protein degradation, ATP supply and structural proteins changed in abundance in response to heat and/or selenium. 40S ribosomal protein SA, FK506-binding protein 10, 65 kDa regulatory subunit A of protein phosphatase 2, protein disulfide isomerase, stress-induced-phosphoprotein 1, suppression of tumorigenicity 13 and collagen type II alpha 1, were differentially expressed in high temperature treatment only. Serine/arginine repetitive matrix protein 1, creatine kinase, serine peptidase inhibitor Kazal type 5 and HSP90 were sensitive to combined temperature and selenium exposure. Valosin-containing protein, a protein involved in aggresome formation and in protein quality control decreased more than 50% in response to selenium treatment. Potential use of such proteins as biomarkers of environmental stressors in larval sturgeons

  6. Impact of nutrition and salinity changes on biological performances of green and white sturgeon.

    PubMed

    Vaz, Pedro G; Kebreab, Ermias; Hung, Silas S O; Fadel, James G; Lee, Seunghyung; Fangue, Nann A

    2015-01-01

    Green and white sturgeon are species of high conservational and economic interest, particularly in the San Francisco Bay Delta (SFBD) for which significant climate change-derived alterations in salinity and nutritional patterns are forecasted. Although there is paucity of information, it is critical to test the network of biological responses underlying the capacity of animals to tolerate current environmental changes. Through nutrition and salinity challenges, climate change will likely have more physiological effect on young sturgeon stages, which in turn may affect growth performance. In this study, the two species were challenged in a multiple-factor experimental setting, first to levels of feeding rate, and then to salinity levels for different time periods. Data analysis included generalized additive models to select predictors of growth performance (measured by condition factor) among the environmental stressors considered and a suite of physiological variables. Using structural equation modeling, a path diagram is proposed to quantify the main linkages among nutrition status, salinity, osmoregulation variables, and growth performances. Three major trends were anticipated for the growth performance of green and white sturgeon in the juvenile stage in the SFBD: (i) a decrease in prey abundance will be highly detrimental for the growth of both species; (ii) an acute increase in salinity within the limits studied can be tolerated by both species but possibly the energy spent in osmoregulation may affect green sturgeon growth within the time window assessed; (iii) the mechanism of synergistic effects of nutrition and salinity changes will be more complex in green sturgeon, with condition factor responding nonlinearly to interactions of salinity and nutrition status or time of salinity exposure. Green sturgeon merits special scientific attention and conservation effort to offset the effects of feed restriction and salinity as key environmental stressors in the

  7. Histopathological alterations of juvenile green (Acipenser medirostris) and white sturgeon (Acipenser transmontanus) exposed to graded levels of dietary methylmercury.

    PubMed

    Lee, Jang-Won; Kim, Jae-Won; De Riu, Nicola; Moniello, Giuseppe; Hung, Silas S O

    2012-03-01

    Triplicate groups of juvenile green and white sturgeon (average weight of 30 ± 2 g) were exposed to one of four concentrations of dietary methylmercury (MeHg; 0, 25, 50, and 100 mg MeHg/kg diet) for 8 weeks to determine and compare the sensitivity of the two sturgeon species from a histopathological perspective. After 4- and 8-week exposure, histological changes were examined in the kidney, liver, gill, skeletal muscle, and heart muscle of both species using light microscopy. Marked abnormalities were observed in the kidney and liver of both sturgeon species after each exposure period; the abnormalities showed progressive histological alterations in severity with increasing doses and duration of exposure. Renal lesions included tubular epithelium degeneration and necrosis, renal corpuscular disintegration, and interstitial tissue degeneration. The changes observed in the livers of both sturgeon species were glycogen depletion and vacuolar degeneration. In the gill and skeletal and heart muscle of green and white sturgeon fed MeHg-added diets, mild histological changes were observed but did not show pronounced difference between the two species. Although the lowest observed effect concentration in both species was the 25 mg MeHg/kg diet, the histological changes in the kidney and liver were more pronounced at all treatments groups of green sturgeon than those of white sturgeon. The current results on structural changes of kidney and liver (i.e., more severe glycogen depletion and tubular epithelium degeneration in green sturgeon) confirmed our previous results, in that green sturgeon exhibited a higher mortality, lower growth rate, and lower protein, lipid, and energy contents in their whole body than white sturgeon under the same MeHg exposures.

  8. Kootenai River White Sturgeon Recovery Implementation Plan and Schedule; 2005-2010, Technical Report 2004-2005.

    SciTech Connect

    Anders, Paul

    2007-03-01

    Kootenai River white sturgeon have been declining for at least 50 years and extinction of the wild population is now imminent (Paragamian et al. 2005). Only 630 adults were estimated to remain in 2002 from a population ten times that size just 20 years ago. Significant recruitment of young sturgeon has not been observed since the early 1970s and consistent annual recruitment has not been seen since the 1950s. The remaining wild population consists of a cohort of large, old fish that is declining by about 9% per year as fish die naturally and are not replaced. At this rate, the wild population will disappear around the year 2040. Numbers have already reached critical low levels where genetic and demographic risks are acute. The Kootenai River White Sturgeon Recovery Team was convened in 1994, provided a draft Recovery Plan in 1996 and the first complete Recovery Plan for Kootenai River white sturgeon in 1999 (USFWS 1996, 1999). The Plan outlined a four part strategy for recovery, including: (1) measures to restore natural recruitment, (2) use of conservation aquaculture to prevent extinction, (3) monitoring survival and recovery, and (4) updating and revising recovery plan criteria and objectives as new information becomes available. Sturgeon recovery efforts are occurring against a backdrop of a broader ecosystem protection and restoration program for the Kootenai River ecosystem. With abundance halving time of approximately 8 years, the Kootenai River white sturgeon population is rapidly dwindling, leaving managers little time to act. Decades of study consistently indicate that recruitment failure occurs between embryo and larval stages. This assertion is based on four key observations. First, almost no recruitment has occurred during the last 30 years. Second, thousands of naturally produced white sturgeon embryos, most viable, have been collected over the past decade, resulting from an estimated 9 to 20 spawning events each year. Third, Kootenai River white

  9. Columbia River White Sturgeon (Acipenser Transmontanus) Population Genetics and Early Life History Study, January 1, 1986 to December 31, 1986, Final Report.

    SciTech Connect

    Brannon, Ernest L.

    1986-12-01

    The 1986 Columbia River white sturgeon investigations continued to assess genetic variability of sturgeon populations isolated in various areas of the Columbia River, and to examine environmental factors in the habitat that may affect early life history success. Baseline data have been collected for three character sets. Twenty-eight loci have been analyzed for differences using electrophoresis, snout shapes were assessed for multivariate distinction, and scute counts have been examined as an index of variability. Fish that reside in the mid-Columbia and lower river have been sufficiently characterized by electrophoresis to compare with up-river areas. To date, few electrophoretic differences have been identified. However, Lake Roosevelt sturgeon sample size will be increased to determine if some of the observed differences from lower river fish are significant. Snout shape has been shown to be easily quantifiable using the digitizing technique. Scute count data initially indicate that variability exists within as well as between areas. Patterns of differentiation of one or more of these data sets may be used to formulate stock transplant guidelines essential for proper management or enhancement of this species. The historical habitat available to sturgeon in the Columbia River has changed through the development of hydroelectric projects. Dams have reduced the velocity and turbulence, and increased light penetration in the water column from less silt. These changes have affected the ability of sturgeon to feed and have made them more vulnerable to predation, which appear to have altered the ability of populations isolated in the reservoirs to sustain themselves. Present studies support the theory that both the biological and physical habitat characteristics of the Columbia River are responsible for reduced sturgeon survival, and justify consideration of enhancement initiatives above Bonneville to improve sturgeon reproductive success.

  10. Columbia River White Sturgeon (Acipenser Transmontanus) Enhancement, May 1-December 31, 1983 Final Report.

    SciTech Connect

    Brannon, E.L.

    1984-12-01

    Studies were undertaken to examine and define the early life history characteristics of Columbia River white sturgeon as a working base from which enhancement measures could be developed. Adult sturgeon were captured and held for spawning at Covert's Landing, the site of the hatchery facilities below Bonneville Dam. Pituitary hormones stimulated ovulation; ripe females were live spawned surgically and the eggs incubated in hatching jars. Larvae were either reared at the hatchery site after incubation to advanced fingerling stages or transferred to the University laboratory for more detailed study. Displacement downstream occurs as a means of distribution and can last several days before a strong substrate preference is manifested. Once bottom contact is sought by the larvae, displacement is abated, and a general preference for sandy surface appears to predominate. Since potentially extensive displacement downstream could result in the distribution of larvae in saltwater, the tolerance of young sturgeon to saltwater was examined. The responsiveness of young sturgeon to artificial feed was positive. With these results, the original concern for identifying an adequate diet and food source that would be readily accepted by fry was greatly attenuated. The readiness of young fry to initiate feeding on the artificial diet made further study on feeding stimulants unnecessary. Examination of the feeding response suggested that as long as the diet used in the present study was initiated at the proper time and with adequate frequency, the fry would feed quite well and survive. 6 refs., 10 figs., 5 tabs.

  11. Effects of incubation substrates on hatch timing and success of White Sturgeon (Acipenser transmontanus) embryos

    USGS Publications Warehouse

    Parsley, Michael J.; Kofoot, Eric

    2013-01-01

    The Kootenai River white sturgeon (Acipenser transmontanus) was listed as endangered under the Endangered Species Act in 1994 because several decades of failed spawning had put the population at risk of extinction. Natural spawning is known to occur at several locations in the Kootenai River, Idaho, but there is little natural recruitment. Microhabitat where embryo incubation occurs is known to be an important factor in white sturgeon reproductive success. This study was conducted to address questions regarding the suitability of different substrates as egg attachment and incubation sites for these fish. A comparative laboratory study using six types of incubation substrates—clean river rocks, periphyton- and algae-covered rocks, waterlogged wood, sand, riparian vegetation, and clean glass plates—tested the hypothesis that survival to hatch of white sturgeon eggs differs among incubation substrates. The results showed that sand was unsuitable as an incubation substrate, as the adhesive embryos were easily dislodged. Periphyton- and algae-covered rocks had the lowest hatch success, and all other substrates had similar hatch success.

  12. Short-term response of subadult white sturgeon to hopper dredge disposal operations

    USGS Publications Warehouse

    Parsley, Michael J.; Popoff, Nicholas D.; Romine, Jason G.

    2011-01-01

    The effect of dredged-material disposal operations on the behavior of seven white sturgeon Acipenser transmontanus (50–101 cm fork length) was examined by analysis of the movements and depth use of these fish before, during, and after a series of hopper dredge disposal operations in the lower Columbia River. Analyses of fish locations showed that 12 flow-lane disposal operations within a 24-h period had minimal effect on subadult white sturgeon behavior; six of the seven fish showed slight attraction to the disposal area during disposals, and one fish increased its distance from the disposal area. The core area for all fish combined shifted toward the disposal area during disposals. In the 24 h after completion of the disposal operations the fish core areas shifted back toward those areas occupied before the disposals. The rates of movement, depths used, and diel movement patterns of the white sturgeon showed little change over all periods, suggesting that natural behaviors were not altered during and immediately after hopper dredge disposal operations.

  13. Effects of subchronic exposure of early life stages of white sturgeon (Acipenser transmontanus) to copper, cadmium, and zinc.

    PubMed

    Vardy, David W; Tompsett, Amber R; Sigurdson, Jacinda L; Doering, Jon A; Zhang, Xiaowei; Giesy, John P; Hecker, Markus

    2011-11-01

    Populations of sturgeon (Acipenseridae) are declining in many places in the world because of several potential factors, including overharvesting, habitat alteration, and pollution. In North America, populations of the white sturgeon (Acipenser transmontanus) have been experiencing poor annual recruitment in major river systems for more than three decades. Metal pollution has been hypothesized as a potential contributing factor to the poor recruitment in some of the water bodies. In general, little is known about the toxicity of metals such as Cu, Cd, and Zn to white sturgeon and their potential influence on survival of embryos and juveniles. The present study was conducted to establish baseline toxicity data for the subchronic exposure of early life stages of white sturgeon to Cu, Cd, and Zn that can be used in metal-related risk assessments. Embryos, larvae, and fry were exposed to increasing concentrations of dissolved Cu, Cd, or Zn for 66 d using laboratory-based flow-through exposure systems. Hatching success was greater than 79% for all controls, and no significant differences were observed among treatment groups or between treatments and controls. Chronic lethal concentrations at which 20% mortality occurred (LC20s) for Cd (1.5 µg/L), Cu (5.5 µg/L), and Zn (112 µg/L) obtained for white sturgeon in the present study were comparable to those of sensitive salmonid species. Based on LC20 values for 19 or 58 d posthatch white sturgeon, the United States national ambient water quality criteria and the Canadian water quality guidelines for the protection of aquatic life that have been established for Cd, Cu, and Zn protect white sturgeon early life stages.

  14. White sturgeon (Acipenser transmontanus) passage at the Dalles Dam, Columbia River, USA

    USGS Publications Warehouse

    Parsley, M.J.; Wright, C.D.; Van Der Leeuw, B. K.; Kofoot, E.E.; Peery, C.A.; Moser, M.L.

    2007-01-01

    White sturgeon (Acipenser transmontanus) ???95 cm TL were monitored using acoustic and radio telemetry at a large hydroelectric dam (the Dalles Dam) on the Columbia River, during March 2004 through November 2005 to determine timing and routes of passage and to characterize general movements. Transmitters were surgically implanted into 148 fish during the study; 90 were released into the tailrace and 58 into the forebay. We documented 26 passage events by 19 tagged fish: eight upstream via fish ladders and 18 downstream, mostly through open spill gates. During the study 17 fish entered the two ladders one or more times; 11 entered only the east ladder, three entered only the north ladder, and three entered both ladders at sometime. Residence time within the ladders by individual fish was variable, ranging from about 1 min to nearly 6 months (median = 7.7 h). Only six fish successfully ascended the east ladder, one fish twice. We could not unequivocally determine which fish ladder one fish used to pass upstream. Differences in construction between the north and east fish ladders may account for the greater success of the east fish ladder in passing sturgeon upstream. Changes to operations at hydroelectric dams to benefit migrating anadromous salmonids may influence upstream or downstream passage by white sturgeon. Altering patterns and timing of spill discharge, altering fish ladder entrance attraction flows, and the use of lights, sound, and partial barriers to direct other species of fish to preferred passage routes have unknown effects on sturgeon passage. A better understanding of the consequences to the metapopulation of increasing or precluding upstream or downstream passage is needed. ?? 2007 The Authors.

  15. Flow and sediment-transport modeling of Kootenai River White Sturgeon Spawning Habitat.

    NASA Astrophysics Data System (ADS)

    McDonald, R. R.; Nelson, J.; Barton, G.; Paragamian, V.

    2004-12-01

    The population of White Sturgeon in the Kootenai River downstream of Libby Dam in Montana and Idaho has declined since the construction of the dam in 1972. The White Sturgeon was listed as endangered in 1994 and an 11.2 mile reach of the river, downstream of Bonners Ferry, Idaho was designated as Critical Habitat in 2001. It is hypothesized that hydro-electric and flood control operations have contributed to poor spawning habitat and recruitment of juvenile fish. The successful incubation of eggs requires a stable and coarse bed material. Currently the sturgeon are spawning in a reach of poor substrate consisting of dunes up to 2 meters in amplitude and composed of fine sand while a short distance upstream there is suitable substrate of coarse gravel. We present here the preliminary results of a flow and sediment-transport modeling effort to aid in an understanding of both the current spawning habitat of the White Sturgeon and the potential to artificially enhance the current spawning habitat or to influence the sturgeon to move upstream to more suitable habitat. A 2.5 dimensional flow model was constructed for an 8-kilometer reach of the designated Critical Habitat. The modeled reach consists of several broad meanders and a mid channel island. The substrate is composed of fine sand with a median grain size of 0.22mm and has large dunes up to 2m in amplitude at relatively lows flows of 200 cms that wash out to a plane bed at around 600 cms. The model has been calibrated to a range of historical flow conditions from 170 cms to 1709 cms and verified against 16 ADCP velocity cross-section profiles collected during a period of steady flow at 554 cms. The model predicts well most of the salient features of the velocity field including the magnitude and location of the secondary flow, using a simple constant value for roughness. However for a few reaches of the river the bed forms and their spatial variability in size are shown to significantly affect the flow and the

  16. Contaminants in white sturgeon (Acipenser transmontanus) from the upper Fraser River, British Columbia, Canada

    SciTech Connect

    MacDonald, D.D.; Ikonomou, M.G.; Rantalaine, A.L.; Rogers, I.H.; Sutherland, D.; Oostdam, J. Van

    1997-03-01

    Four white sturgeon were collected from the upper Fraser River near Prince George, British Columbia, Canada, in the fall of 199a and 1992. Two additional fish were taken from the Fraser River near Williams Lake, some 250 km downstream of Prince George. Samples of white muscle, red muscle, liver, and roe were analyzed for metals, polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), non-ortho and mono-ortho polychlorinated biphenyls (PCBs), and chlorophenols to determine whether the tissues of this species were acceptable for human consumption. The concentrations of mercury in the white muscle and liver of several fish from the upper Fraser River exceeded the provincial tissue residue criteria for people who consumed low quantities of fish. The concentrations of PCDDs, PCDFs, and coplanar PCBs (expressed as 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents) in red muscle and liver of these fish exceeded the Health Canada working guidelines for the protection of human health. By comparison, white sturgeon collected in the lower Fraser River had much lower concentrations of metals and organic contaminants. The differences in contaminant burdens in fish from the two widely separated reaches of the river reflect their proximity to or distance from known contaminant sources.

  17. White Sturgeon Mitigation and Restoration in the Columbia and Snake Rivers Upstream from Bonneville Dam; 2004-2005 Annual Report.

    SciTech Connect

    Rien, Thomas A.; Hughes, Michele L.; Kern, J. Chris

    2006-03-01

    We report on our progress from April 2004 through March 2005 on determining the effects of mitigative measures on productivity of white sturgeon populations in the Columbia River downstream from McNary Dam, and on determining the status and habitat requirements of white sturgeon populations in the Columbia and Snake rivers upstream from McNary Dam. This is a multi-year study with many objectives requiring more than one year to complete; therefore, findings from a given year may be part of more significant findings yet to be reported.

  18. White Sturgeon Mitgation and Restoration in the Columbia and Snake Rivers Upstream from Bonneville Dam; 2003-2004 Annual Report.

    SciTech Connect

    Rein, Thomas A.; Hughes, Michele L.; Kern, J. Chris

    2005-08-01

    We report on our progress from April 2003 through March 2004 on determining the effects of mitigative measures on productivity of white sturgeon populations in the Columbia River downstream from McNary Dam, and on determining the status and habitat requirements of white sturgeon populations in the Columbia and Snake rivers upstream from McNary Dam. This is a multi-year study with many objectives requiring more than one year to complete; therefore, findings from a given year may be part of more significant findings yet to be reported.

  19. Sediment Characteristics and Transport in the Kootenai River White Sturgeon Critical Habitat near Bonners Ferry, Idaho

    USGS Publications Warehouse

    Fosness, Ryan L.; Williams, Marshall L.

    2009-01-01

    Recovery efforts for the endangered Kootenai River population of white sturgeon require an understanding of the characteristics and transport of suspended and bedload sediment in the critical habitat reach of the river. In 2007 and 2008, the U.S. Geological Survey in cooperation with the Kootenai Tribe of Idaho, conducted suspended- and bedload-sediment sampling in the federally designated critical habitat of the endangered Kootenai River white sturgeon population. Three sediment-sampling sites were selected that represent the hydraulic differences in the critical habitat. Suspended- and bedload-sediment samples along with acoustic Doppler current profiles were collected at these sites during specific river discharges. Samples were analyzed to determine suspended- and bedload-sediment characteristics and transport rates. Sediment transport data were analyzed to provide total loading estimates for suspended and bedload sediment in the critical habitat reach. Total suspended-sediment discharge primarily occurred as fine material that moved through the system in suspension. Total suspended-sediment discharge ranged from about 300 metric tons per day to more than 23,000 metric tons per day. Total suspended sediment remained nearly equal throughout the critical habitat, with the exception of a few cases where mass wasting of the banks may have caused sporadic spikes in total suspended sediment. Bedload-sediment discharge averaged 0-3 percent of the total loading. These bedload discharges ranged from 0 to 271 tons per day. The bedload discharge in the upper part of the critical habitat primarily consisted of fine to coarse gravel. A decrease in river competence in addition to an armored channel may be the cause of this limited bedload discharge. The bedload discharge in the middle part of the white sturgeon critical habitat varied greatly, depending on the extent of the backwater from Kootenay Lake. A large quantity of fine-to-coarse gravel is present in the braided

  20. Ontogenetic behavior and dispersal of Sacramento River white sturgeon, Acipenser transmontanus, with a note on body color

    USGS Publications Warehouse

    Kynard, B.; Parker, E.

    2005-01-01

    We studied Sacramento River white sturgeon, Acipenser transmontanus, in the laboratory to develop a conceptual model of ontogenetic behavior and provide insight into probable behavior of wild sturgeon. After hatching, free embryos initiated a low intensity, brief downstream dispersal during which fish swam near the bottom and were photonegative. The weak, short dispersal style and behavior of white sturgeon free embryos contrasts greatly with the intense, long dispersal style and behavior (photopositive and swimming far above the bottom) of dispersing free embryos of other sturgeon species. If spawned eggs are concentrated within a few kilometers downstream of a spawning site, the adaptive significance of the free embryo dispersal is likely to move fish away from the egg deposition site to avoid predation and reduce fish density prior to feeding. Larvae foraged on the open bottom, swam <1 m above the bottom, aggregated, but did not disperse. Early juveniles initiated a strong dispersal with fish strongly vigorously swimming downstream. Duration of the juvenile dispersal is unknown, but the strong swimming likely disperses fish many kilometers. Recruitment failure in white sturgeon populations may be a mis-match between the innate fish dispersal and post-dispersal rearing habitat, which is now highly altered by damming and reservoirs. Sacramento River white sturgeon has a two-step downstream dispersal by the free embryo and juvenile life intervals. Diel activity of all life intervals peaked at night, whether fish were dispersing or foraging. Nocturnal behavior is likely a response to predation, which occurs during both activities. An intense black-tail body color was present on foraging larvae, but was weak or absent on the two life intervals that disperse. Black-tail color may be an adaptation for avoiding predation, signaling among aggregated larvae, or both, but not for dispersal. ?? Springer 2005.

  1. Infilling of Cobble Substrate used by White Sturgeon on the Nechako River, at Vanderhoof BC

    NASA Astrophysics Data System (ADS)

    Zimmermann, A. E.; Argast, T.; Sary, Z.

    2013-12-01

    Nechako white sturgeon are experiencing a recruitment failure, which has been attributed to the failure of eggs and larvae to survive as a result of changes in the substrate at the locations where they are known to spawn. As part of the overall recovery effort initiative, cobble substrate was placed at two locations to provide clean spawning substrate. Subsequently, the condition of the substrate has been investigated using an underwater camera and freeze core sampling. These observations have shown that coarse sand and fine gravels (fine bedoad) have in-filled the coarse substrate where it was placed along the inside corner of the bends, while placed substrate located on the outside of the bends has remained free of this size fraction. This observation has lead to the quandary: Is placed cobble substrate on the outside corner of the bends not being filled in with fine bedload because fine bedload is not moving past these sites, or are post-regulation flood flows sufficient to ensure fines remain suspended and are not deposited in the interstitial spaces? To assess this question a number of field based techniques will be used in August of 2013 during high flows to examine the movement of fine bedload. The techniques employed will include an underwater camera, P61 suspended sediment sampler, a HellySmith and KAROLYI bedload sampler and an ADCP with RTK for bottom tracking. The intent is to examine the movement of fine bedload across the channel at a number of potential spawning sites. The poster will summarize the observations to date about the movement of fine bedload at the spawning sites, and discuss the implications for spawning substrate improvement efforts.

  2. Effects of Mitigative Measures on Productivity of White Sturgeon Populations in the Columbia River Downstream from McNary Dam; Determine Status and Habitat Requirements of White Sturgeon Populations in the Columbia and Snake Rivers Upstream from the McNary Dam, 1994-1995 Annual Report.

    SciTech Connect

    Beiningen, Kirk T.

    1996-03-01

    The author reports on progress from April 1994 through March 1995 of research on white sturgeon in the lower Columbia River. The study began in July 1986 and is a cooperative effort of federal, state and tribal fisheries entities to determine the (1) the status and habitat requirements, and (2) the effects of mitigative measures on productivity of white sturgeon populations in the lower Columbia River. This report describes activities conducted during the third year of this contract's second phase. Information was collected, analyzed, and evaluated on sub-adult and adult life histories, population dynamics, quantity and quality of habitat, and production enhancement strategies. The report is divided into sections that evaluate success of developing and implementing a management plan for white sturgeon; evaluate growth, mortality, and contributions to fisheries of juvenile white sturgeon transplanted from areas downstream; describe the life history and population dynamics of sub-adult a nd adult white sturgeon; define habitat requirements for spawning and rearing of white sturgeon and quantify the extent of habitat available; describe reproductive and early life history characteristics of white sturgeon; and quantify physical habitat used by spawning and rearing white sturgeon in the free-flowing portion of the Columbia River.

  3. Movement, swimming speed, and oxygen consumption of juvenile white sturgeon in response to changing flows, water temperatures, and light level in the Snake River, Idaho

    SciTech Connect

    Geist, David R.; Brown, Richard S.; Cullinan, Valerie I.; Brink, Steve R.; Lepla, Kenneth B.; Bates, Phil; Chandler, James A.

    2005-07-01

    The flow of the Snake River downstream of Hells Canyon Dam, Idaho, frequently fluctuates as the dam responds to power production requirements. These flow fluctuations have the potential to increase the energy used by individual juvenile white sturgeon (Acipenser transmontanus) that move to avoid unfavorable habitat or that alter their swimming speeds to maintain position over a range of velocities. Following swimming respirometry experiments, a field study using electromyogram (EMG) and sonic telemetry evaluated whether sturgeon were being negatively affected by operations of Hells Canyon Dam during three study periods where flows were artificially fluctuated (247 to 856 m3/s), held high and stable (438 to 600 m3/s), or held low and stable (275 to 284 m3/s). Respirometry results confirmed that oxygen consumption of juvenile sturgeon increased with swim speed and was temperature dependent, and when corrected for fish mass, ranged from 140.2 to 306.5 mg O2 kg-1 h-1. The telemetry study showed that movements and activity levels, as measured by swimming speeds and oxygen consumption, of sturgeon were variable among fish and across study periods. When flows were held low and stable, sturgeon movement increased while activity levels decreased when compared to the study periods when flows were variable or were high and stable. Although the overall trend was for activity levels to be less during the study period when flows were low and stable, the majority of differences between study periods appeared to be due to differences in water temperature and light levels that changed during the three-month investigation. The results suggest high flows, even those of relatively short durations such as what occurs during load-following operations, restrict the movement of juvenile sturgeon, but do not result in an increase of energy expenditure, possibly because of morphological and behavioral adaptations to living in a high-velocity environment. This may have significant

  4. White Sturgeon Research Needs: Workshop Results, Seattle, Washington, November 3-4, 1983.

    SciTech Connect

    Fickeisen, Duane H.; Neitzel, D.A.; Dauble, Dennis D.

    1984-02-01

    This report describes the results of a workshop to develop a research program for Columbia River Basin white surgeon. Invited participants developed a list of white sturgeon research needs and rationale for ranking the relative importance of the research needs. The highest ranked research needs were: define physical habitat requirements (substrate, flow, water quality) for early life history stages; identify genetic stocks; assess population status (e.g., distribution, densities, age-structure, year-class strength, age-specific mortality, disease, parasitism); assess reproductive status (e.g., spawning success, recruitment, age/size-dependent fecundity); develop new sampling techniques and gear for collecting early life history stages; assess gametogenesis (timing of maturation, frequency of spawning), including effects of environmental factors on gonadal development; and define physical habitat requirements (substrate, flow, water quality) for spawning. 2 references, 2 figures, 5 tables.

  5. Absorption, distribution, and elimination of graded oral doses of methylmercury in juvenile white sturgeon.

    PubMed

    Huang, Susie Shih-Yin; Strathe, Anders Bjerring; Fadel, James G; Lin, Pinpin; Liu, Tsung-Yun; Hung, Silas S O

    2012-10-15

    Mercury (Hg) is toxic and is released into the environment from a wide variety of anthropogenic sources. Methylmercury (MeHg), a product of microbial methylation, enables rapid Hg bioaccumulation and biomagnification in the biota. Methylmercury is sequestered and made available to the rest of the biota through the benthic-detrital component leading to the high risk of exposure to benthic fish species, such as white sturgeon (Acipenser transmontanus). In the present study, a combined technique of stomach intubation, dorsal aorta cannulation, and urinary catheterization was utilized to characterize the absorption, distribution, and elimination of Hg in white sturgeon over a 48h exposure. Mercury, as methylmercury chloride, at either 0, 250, 500, or 1000 μg Hg/kg body weight, was orally intubated into white sturgeon, in groups of five. The blood was repeatedly sampled and urine collected from the fish over the 48h post intubation period, and at 48h, the fish were sacrificed for Hg tissue concentration and distribution determinations. The fractional rate of absorption (K), blood Hg concentration (μg/ml), tissue concentration (μg/g dry weight) and distribution (%), and urinary Hg elimination flux (μg/kg/h) are significantly different (p<0.05) among the MeHg doses. Complete blood uptake of Hg was observed in all MeHg treated fish by 12h. The maximal observed blood Hg concentration peaks are 0.56±0.02, 0.70±0.02, and 2.19±0.07 μg/ml (mean±SEM) for the 250, 500, and 1000 μgHg/kg body weight dose groups, respectively. Changes in blood Hg profiles can be described by a monomolecular function in all of the MeHg treated fish. The Hg concentration asymptote (A) and K are dose dependent. The relationship between A and the intubation dose, however, is nonlinear. Mercury levels in certain tissues are comparable to field data and longer-term study, indicating that the lower doses used in the current study are ecologically relevant for the species. Tissue Hg concentrations

  6. Assessment of the risk of White Sturgeon to become infected and potential carriers of infectious pancreatic necrosis virus.

    PubMed

    LaPatra, Scott E; Mead, Sherry

    2013-12-01

    Little scientific information is available to assess whether White Sturgeon Acipenser transmontanus can become infected and potential carriers of infectious pancreatic necrosis virus (IPNV). To assess this risk, monitoring results of adult and progeny White Sturgeon were examined from waters historically stocked with salmonid fish known to be IPNV carriers. From 1999 through 2004 White Sturgeon from a total of 30 separate families whose parentage came from waters historically stocked with IPNV carrier fish were tested. Duplicate groups of 25 juvenile Snake River White Sturgeon were waterborne exposed to 1.0×10(4) 50% tissue culture infective dose (TCID50)/mL of water for 1 h and an additional group was injected intraperitoneally with 1.0×10(5) TCID50/fish. A negative control group was handled similarly but was not exposed to the virus. No morbidity was detected in any of the treatment groups or the negative control. At 34, 40, 47, and 54 d postexposure to IPNV, virus reisolation was attempted on five fish from each group, and an additional five fish from each group were examined for histological changes consistent with an IPNV infection. At 34 and 40 d postinjection with IPNV, 20% (one of five) of the fish tested positive for the virus per sample interval; however, fish from groups that were waterborne-exposed to IPNV were all negative. At 47 and 54 d after exposure or injection with IPNV an additional five fish from each group were tested at each sample interval and all results were negative. Histological analysis of target tissue obtained from five fish per group at 34 and 54 d postinfection also failed to detect any consistent change associated with an IPNV infection. These results suggest that the risk of White Sturgeon to become infected and develop into potential carriers of IPNV is negligible.

  7. The Pallid Sturgeon: Scientific Investigations Help Understand Recovery Needs

    USGS Publications Warehouse

    DeLonay, Aaron J.

    2010-01-01

    Understanding of the pallid sturgeon (Scaphirhynchus albus) has increased significantly since the species was listed as endangered over two decades ago. Since 2005, scientists at the U.S. Geological Survey (USGS) Columbia Environmental Research Center (CERC) have been engaged in an interdisciplinary research program in cooperation with the U.S. Army Corps of Engineers Missouri River Recovery Program, U.S. Fish and Wildlife Service, Nebraska Game and Parks Commission, and numerous other State and Federal cooperators to provide managers and policy makers with the knowledge needed to evaluate recovery options. During that time, the USGS has worked collaboratively with river scientists and managers to develop methods, baseline information, and research approaches that are critical contributions to recovery success. The pallid sturgeon is endangered throughout the Missouri River because of insufficient reproduction and survival of early life stages. Primary management actions on the Missouri River designed to increase reproductive success and survival have focused on flow regime, channel morphology, and propagation. The CERC research strategies have, therefore, been designed to examine the linkages among flow regime, re-engineered channel morphology, and reproductive success and survival. Specific research objectives include the following: (1) understanding reproductive physiology of pallid sturgeon and relations to environmental conditions; (2) determining movement, habitat use, and reproductive behavior of pallid sturgeon; and (3) quantifying availability and dynamics of aquatic habitats needed by pallid sturgeon for all life stages.

  8. Effects of sediment cover on survival and development of white sturgeon embryos

    USGS Publications Warehouse

    Kock, T.J.; Congleton, J.L.; Anders, P.J.

    2006-01-01

    A simple, inexpensive apparatus (embryo incubation unit [EIU]) was developed and used to assess the relationship between sediment cover (Kootenai River sediments, 97% by weight in the 0.83-mm- to 1.0-mm-diameter range) and survival of white sturgeon Acipenser transmontanus embryos in the laboratory. An apparatus-testing trial assessed the effects of two sediment depths (5 and 20 mm), three EIU ventilation hole sizes (4.8, 6.8, and 9.5 mm) providing three levels of intrasediment flow, and EIU location (upstream or downstream in laboratory troughs) on embryo survival at two above-substrate flow velocities (0.05 and 0.15 m/s). A second trial assessed the effects of sediment cover duration (5-mm sediment cover for 4, 7, 9, 11, or 14 d, with a ventilation hole size of 9.5 mm and a flow velocity of 0.17 m/s) on mean embryo survival and larval length and weight. In the apparatus-testing trial, embryo survival was reduced (P < 0.0001) to 0-5% under sediment covers of either 5 or 20 mm in both the higher-flow and lower-flow troughs; survival in control EIUs without sediments exceeded 80%. Survival was not significantly affected by ventilation hole size but was weakly affected by EIU location. In the second trial, embryo survival was negatively correlated (P = 0.001) with increasing duration of sediment cover and was significantly higher for embryos covered for 4 d (50% survival) or 7 d (30% survival) than for those covered for 9, 11, or 14 d (15-20% survival). Sediment cover also delayed hatch timing (P < 0.0001) and decreased mean larval length (P < 0.0001). Our results suggest that sediment cover may be an important early life stage mortality factor in rivers where white sturgeon spawn over fine-sediment substrates. ?? Copyright by the American Fisheries Society 2006.

  9. Summary of Stock Identification Research on White Sturgeon of the Columbia River, 1985-1991 Final Report.

    SciTech Connect

    Setter, Ann L.; Brannon, E.L.

    1992-01-01

    White sturgeon (Acipenser transmontanus) are a long-lived, primitive fish species which forage primarily along the river bottom of large river systems in the Pacific Northwest. Historically, as an anadromous species, they could distribute downstream to feed in the rich estuary or marine areas and then migrate back up the river to spawn. With the historic river becoming a series of flooded impoundments, sturgeon were denied open river access, but they appear to have been able to adapt to the altered environment. White sturgeon are found throughout the Columbia River and are thought to be successfully reproducing in some of the impoundments. In those reservoirs where little or no reproduction takes place, enhancement hatcheries may be an option for use in rebuilding isolated populations. However, the degree of stock specificity that exists in the Columbia River was unknown and precluded the use of the more abundant lower river fish as a common egg source to repropagate the upper river unless genetic similarity could be demonstrated among sturgeon throughout the river system. To resolve the issue, research was conducted to determine what level of genetic differentiation exists among sturgeon in the Columbia River system, using starch gel electrophoresis to enable a baseline of population genetic structure data to be assembled. A greater diversity in electrophoretic pattern was observed in the lower portions of the river. The bulk of the qualitative variability we noted was consistent throughout all sections of the river. Some specific quantitative differences were apparent between the areas we examined. Interpretation of the results was complicated by the fact that dam construction would tend to isolate and mix stocks by preventing the migration of fish returning upstream.

  10. Differences in the dynamics and potential production of impounded and unimpounded white sturgeon populations in the lower Columbia River

    SciTech Connect

    Beamesderfer, R.C.P.; Rien, T.A.; Nigro, A.A.

    1995-11-01

    White sturgeons Acipenser transmontanus were sampled in three lower Columbia River reservoirs from 1987 to 1991 to describe population dynamics, the ability of these stocks to sustain harvest, and differences among reservoir and unimpounded populations. Significant differences were observed among reservoirs in white sturgeon abundance, biomass, size composition, sex ratio, size of females at maturity, growth rate, condition factor, and rate of exploitation. No differences among reservoirs were detected in fecundity, natural mortality rate, or longevity, in part because of sampling difficulties. Recruitment rates and densities in reservoirs were inversely correlated with growth rate, condition factor, and size of females at maturity. Differences in population dynamics resulted in substantial differences in sustainable yields. Maximum yields per recruit were predicted at annual exploitation rates between 5 and 15%. Most characteristics of reservoir populations were less than or equal to optima reported for the unimpounded lower river; as a result, yield per recruit, reproductive potential per recruit, and the number of recruits were less in reservoirs than in the unimpounded river. Comparisons with pristine standing stocks suggest that the unimpounded river may approximate preimpoundment conditions for white sturgeon. We conclude that potential yield from impounded populations has been reduced by dam construction, which restricts populations to river segments that may not include conditions optimal for all life stages. Alternatives for enchancement of reservoir populations might include improved passage at dams, increased spring flow to improve spawning success, transplants from productive populations, hatchery supplementation, and more intensive harvest management. 54 refs., 7 figs., 7 tabs.

  11. Acute and chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures

    USGS Publications Warehouse

    Ingersoll, Christopher G.; Contributions by Wang, Ning; Calfee, Robin D.; Beahan, Erinn; Brumbaugh, William G.; Dorman, Rebecca A.; Hardesty, Doug K.; Kunz, James L.; Little, Edward E.; Mebane, Christopher A.; Puglis, Holly J.

    2014-01-01

    White sturgeon (Acipenser transmontanus) are experiencing poor recruitment in the trans boundary reach of the upper Columbia River in eastern Washington State. Limited toxicity data indicated that early life stages of white sturgeon are sensitive to metals. In acute 4-day (d) exposures with larval white sturgeon, previous studies have reported that the 4-day median lethal concentrations (LC50) based on biotic ligand model (BLM) normalization for copper were below the U.S. Environmental Protection Agency national recommended acute water-quality criterion. In previously published chronic 66-d exposures starting with newly fertilized eggs of white sturgeon, 20-percent lethal effect concentrations (LC20s) for copper, cadmium, or zinc generally were within a factor of two of the chronic values of the most sensitive fish species in the databases of the U.S. Environmental Protection Agency water-quality criteria (WQC) for the three metals. However, there were some uncertainties in the chronic exposures previously performed with white sturgeon, including (1) low control survival (37 percent), (2) more control fish tested in each replicate compared to other treatments, (3) limited replication of treatments (n=2), (4) lack of reported growth data (such as dry weight), and (5) wide dilution factors for exposure concentrations (6- to 8-fold dilutions). The U.S. Environmental Protection Agency concluded that additional studies are needed to generate more toxicity data to better define lethal and sublethal toxicity thresholds for metals for white sturgeon. The objective of the study was to further evaluate the acute and chronic toxicity of cadmium, copper, lead, or zinc to early life stages of white sturgeon in water-only exposures. Toxicity tests also were performed with commonly tested rainbow trout (Oncorhynchus mykiss) under similar test conditions to determine the relative sensitivity between white sturgeon and rainbow trout to these metals. Toxicity data generated from

  12. Selenium tissue burden compartmentalization in resident white sturgeon (Acipenser transmontanus) of the San Francisco Bay Delta estuary.

    PubMed

    Linares-Casenave, Javier; Linville, R; Van Eenennaam, J P; Muguet, J B; Doroshov, S I

    2015-01-01

    High selenium (Se) loads in the San Francisco Bay Delta are bioaccumulated and biomagnified in food webs and can impair the reproduction of resident oviparous animals such as white sturgeon. The objective of the present study was to determine the Se tissue burden in San Francisco Bay Delta-resident white sturgeon to assess Se bioaccumulation in different organs, including ovaries and liver where egg yolk precursor proteins are synthesized. The authors obtained 54 San Francisco Bay Delta-resident white sturgeon including 26 female and 28 male subadults with immature gonads, 8 females with vitellogenic eggs, and 13 males with maturing gonads. Length, weight, age, reproductive stage of development, and kidney, liver, gonad, and muscle Se concentrations were determined in all fish. Concentrations of Se in muscle, gonads, and liver significantly increased with fish size, whereas kidney Se was not correlated to body size and was at the highest level compared with other organs. There was no difference between the sexes (p > 0.05) in Se concentrations in kidney (12.83 ± 0.51 µg · g(-1) dry wt), liver (11.85 ± 1.04 µg · g(-1) dry wt), and muscle (7.09 ± 0.52 µg · g(-1) dry wt; mean ± standard error, n = 47); but Se concentration was higher in the ovary than in testis (p = 0.04). Females with vitellogenic eggs had higher Se concentrations in the ovaries (20.77 ± 4.11 µg · g(-1) dry wt vs 5.22 ± 2.50 µg · g(-1) dry wt), liver (21.84 ± 2.07 µg · g(-1) dry wt vs 8.03 ± 1.03 µg · g(-1) dry wt), and muscle (10.18 ± 1.93 µg · g(-1) dry wt vs 5.48 ± 0.64 µg · g(-1) dry wt) compared with less advanced, previtellogenic females (p < 0.05). The elevated Se concentrations in the ovaries and liver of vitellogenic San Francisco Bay Delta white sturgeon were comparable with levels previously shown to cause reproductive toxicity in dietary Se experiments

  13. Evaluation of Reconnection Options for White Sturgeon in the Snake River Using a Population Viability Model

    SciTech Connect

    Jager, Yetta; Bevelhimer, Mark S; Chandler, James A.; Lepla, Ken B.; Van Winkle, Webb

    2007-01-01

    Abstract.- This paper describes a simulation study of reconnection options for white sturgeon Acipenser transmontanus subpopulations in adjacent river segments above and below CJ Strike Dam on the Snake River, Idaho, USA. In contrast to the downstream river segment, the upstream river segment is long and has areas that are suitable for spawning during normal and wet hydrologic conditions. We evaluated demographic and genetic consequences of upstream and downstream passage using different model assumptions about trashrack spacing and density dependent effects on the spawning interval. Our genetic results predict that, although reconnection would introduce new alleles to the upstream subpopulation, it would also preserve alleles from the downstream subpopulation by propagating them in the larger subpopulation above the dam. Our demographic results predict that halving the space between trashracks would have large and unequivocal benefits, whereas the effects of reconnection would be smaller and more sensitive to model assumptions. Simulated upstream passage tended to benefit both subpopulations only in the absence of density dependent limitation. In the presence of density dependence, the combination of halved trashrack spacing and upstream and downstream passage produced the best results. Narrower trashracks kept spawning adults in the upstream segment with spawning habitat, while allowing their progeny to migrate downstream. Screening appears to be the best option for such a species in this configuration of a long river segment acting as a demographic source above a short one acting as a demographic sink.

  14. Vulnerability of larval and juvenile white sturgeon to barotrauma: can they handle the pressure?

    PubMed

    Brown, Richard S; Cook, Katrina V; Pflugrath, Brett D; Rozeboom, Latricia L; Johnson, Rachelle C; McLellan, Jason G; Linley, Timothy J; Gao, Yong; Baumgartner, Lee J; Dowell, Frederick E; Miller, Erin A; White, Timothy A

    2013-01-01

    Techniques were developed to determine which life stages of fish are vulnerable to barotrauma from expansion of internal gases during decompression. Eggs, larvae, and juvenile hatchery-reared white sturgeon (Acipenser transmontanus; up to 91 days post hatch; d.p.h.) were decompressed to assess vulnerability to barotrauma and identify initial swim bladder inflation. Barotrauma-related injury and mortality were first observed 9 d.p.h., on the same day as initial exogenous feeding. However, barotrauma-related injury did not occur again until swim bladder inflation 75 d.p.h. (visible at necropsy and on radiographs). Swim bladder inflation was not consistent among individuals, with only 44% being inflated 91 d.p.h. Additionally, swim bladder inflation did not appear to be size dependent among fish ranging in total length from 61 to 153 mm at 91 d.p.h. The use of a combination of decompression tests and radiography was validated as a method to determine initial swim bladder inflation and vulnerability to barotrauma. Extending these techniques to other species and life-history stages would help to determine the susceptibility of fish to hydro turbine passage and aid in fish conservation. PMID:27293603

  15. Vulnerability of larval and juvenile white sturgeon to barotrauma: can they handle the pressure?

    PubMed

    Brown, Richard S; Cook, Katrina V; Pflugrath, Brett D; Rozeboom, Latricia L; Johnson, Rachelle C; McLellan, Jason G; Linley, Timothy J; Gao, Yong; Baumgartner, Lee J; Dowell, Frederick E; Miller, Erin A; White, Timothy A

    2013-01-01

    Techniques were developed to determine which life stages of fish are vulnerable to barotrauma from expansion of internal gases during decompression. Eggs, larvae, and juvenile hatchery-reared white sturgeon (Acipenser transmontanus; up to 91 days post hatch; d.p.h.) were decompressed to assess vulnerability to barotrauma and identify initial swim bladder inflation. Barotrauma-related injury and mortality were first observed 9 d.p.h., on the same day as initial exogenous feeding. However, barotrauma-related injury did not occur again until swim bladder inflation 75 d.p.h. (visible at necropsy and on radiographs). Swim bladder inflation was not consistent among individuals, with only 44% being inflated 91 d.p.h. Additionally, swim bladder inflation did not appear to be size dependent among fish ranging in total length from 61 to 153 mm at 91 d.p.h. The use of a combination of decompression tests and radiography was validated as a method to determine initial swim bladder inflation and vulnerability to barotrauma. Extending these techniques to other species and life-history stages would help to determine the susceptibility of fish to hydro turbine passage and aid in fish conservation.

  16. Vulnerability of larval and juvenile white sturgeon to barotrauma: can they handle the pressure?

    SciTech Connect

    Brown, Richard S.; Cook, Katrina V.; Pflugrath, Brett D.; Rozeboom, Latricia L.; Johnson, Rachelle C.; McLellan, Jason; Linley, Timothy J.; Gao, Yong; Baumgartner, Lee J.; Dowell, Frederick E.; Miller, Erin A.; White, Timothy A.

    2013-07-01

    Techniques were developed to determine which life stages of fish are vulnerable to barotrauma from expansion of internal gases during decompression. Eggs, larvae and juvenile hatchery-reared white sturgeon (Acipenser transmontanus; up to 91 days post hatch; dph), were decompressed to assess vulnerability to barotrauma and identify initial swim bladder inflation. Barotrauma related injury and mortality were first observed 9 dph, on the same day as initial exogenous feeding. However, barotrauma related injury did not occur again until swim bladder inflation 75 dph (visible from necropsy and x-ray radiographs). Swim bladder inflation was not consistent among individuals, with only 44% being inflated 91 dph. Additionally, swim bladder inflation did not appear to be size dependent among fish ranging in total length from 61-153 mm at 91 dph. The use of a combination of decompression tests and x-ray radiography was validated as a method to determine initial swim bladder inflation and vulnerability to barotrauma. Extending these techniques to other species and life history stages would help to determine fish susceptibility to hydroturbine passage and aid in fish conservation.

  17. Sediment cores and chemistry for the Kootenai River White Sturgeon Habitat Restoration Project, Boundary County, Idaho

    USGS Publications Warehouse

    Barton, Gary J.; Weakland, Rhonda J.; Fosness, Ryan L.; Cox, Stephen E.; Williams, Marshall L.

    2012-01-01

    The Kootenai Tribe of Idaho, in cooperation with local, State, Federal, and Canadian agency co-managers and scientists, is assessing the feasibility of a Kootenai River habitat restoration project in Boundary County, Idaho. This project is oriented toward recovery of the endangered Kootenai River white sturgeon (Acipenser transmontanus) population, and simultaneously targets habitat-based recovery of other native river biota. Projects currently (2010) under consideration include modifying the channel and flood plain, installing in-stream structures, and creating wetlands to improve the physical and biological functions of the ecosystem. River restoration is a complex undertaking that requires a thorough understanding of the river. To assist in evaluating the feasibility of this endeavor, the U.S. Geological Survey collected and analyzed the physical and chemical nature of sediment cores collected at 24 locations in the river. Core depths ranged from 4.6 to 15.2 meters; 21 cores reached a depth of 15.2 meters. The sediment was screened for the presence of chemical constituents that could have harmful effects if released during restoration activities. The analysis shows that concentrations of harmful chemical constituents do not exceed guideline limits that were published by the U.S. Army Corps of Engineers in 2006.

  18. Genetic and demographic implications of aquaculture in white sturgeon (Acipenser transmontanus)conservation

    SciTech Connect

    Jager, Yetta

    2005-01-01

    This study uses a genetic individual-based model of white sturgeon (Acipenser transmontanus) populations in a river to examine the genetic and demographic trade-offs associated with operating a conservation hatchery. Simulation experiments evaluated three management practices: (i) setting quotas to equalize family contributions in an effort to prevent genetic swamping, (ii) an adaptive management scheme that interrupts stocking when introgression exceeds a specified threshold, and (iii) alternative broodstock selection strategies that influence domestication. The first set of simulations, designed to evaluate equalizing the genetic contribution of families, did not show the genetic benefits expected. The second set of simulations showed that simulated adaptive management was not successful in controlling introgression over the long term, especially with uncertain feedback. The third set of simulations compared the effects of three alternative broodstock selection strategies on domestication for hypothetical traits controlling early density-dependent survival. Simulated aquaculture selected for a density-tolerant phenotype when broodstock were taken from a genetically connected population. Using broodstock from an isolated population (i.e., above an upstream barrier or in a different watershed) was more effective at preventing domestication than using wild broodstock from a connected population.

  19. Status and Habitat Requirements of White Sturgeon Populations in the Columbia River Downstream from McNary Dam, 1988-1989 Annual Report.

    SciTech Connect

    Nigro, Anthony A. )

    1989-09-01

    We report on our progress from April 1988 through March 1989 on determining the status and habitat requirements of white sturgeon populations in the Columbia River downstream from McNary Dam. Highlights of results of our work in the Dalles and Bonneville reservoirs are: using setlines, we caught 1,586 sturgeon in The Dalles Reservoir and 484 sturgeon in Bonneville Reservoir in 1988. Fork length of fish caught ranged from 34 cm to 274 cm. Of the fish caught we marked 1,248 in The Dalles Reservoir and 341 in Bonneville Reservoir. Of the fish marked in 1988, we recaptured 82 in The Dalles Reservoir and none in Bonneville Reservoir. We recaptured 89 fish marked in 1987 in The Dalles Reservoir. Anglers recaptured 35 fish marked in 1988 and 16 fish marked in 1987 in The Dalles Reservoir. Anglers recaptured 2 sturgeon marked in 1988 in Bonneville Reservoir. Individual papers were processed separately for the data base.

  20. A simulation study of factors controlling white sturgeon recruitment in the Snake River

    USGS Publications Warehouse

    Jager, H.I.; Van Winkle, W.; Chandler, James Angus; Lepla, K.B.; Bates, P.; Counihan, T.D.

    2002-01-01

    Five of the nine populations of white sturgeon Acipenser transmontanus, located between dams on the Middle Snake River, have declined from historical levels and are now at risk of extinction. One step towards more effectively protecting and managing these nine populations is ranking factors that influence recruitment in each of these river segments. We developed a model to suggest which of seven mechanistic factors contribute most to lost recruitment in each river segment: (1) temperature-related mortality during incubation, (2) flow-related mortality during incubation, (3) downstream export of larvae, (4) limitation of juvenile and adult habitat, (5) mortality of all ages during summer episodes of poor water quality in reservoirs, (6) entrainment mortality of juveniles and adults, and (7) angling mortality. We simulated recruitment with, and without, each of the seven factors, over a typical series of hydrologic years. We found a hierarchical pattern of limitation. In the first tier, river segments with severe water quality problems grouped together. Poor water quality during summer had a strong negative effect on recruitment in the river segments between Swan Falls Dam and Hell's Canyon Dam. In the second tier, river segments with better water quality divided into short river segments and longer river segments. Populations in short river segments were limited by larval export. Populations in longer river segments tended to be less strongly limited by any one factor. We also found that downstream effects could be important, suggesting that linked populations cannot be viewed in isolation. In two cases, the effects of a factor on an upstream population had a significant influence on its downstream neighbors. ?? 2002 by the American Fisheries Society.

  1. Effects of thermal regime on ovarian maturation and plasma sex steroids in farmed white sturgeon, Acipenser transmontanus

    USGS Publications Warehouse

    Webb, M.A.H.; Van Eenennaam, J. P.; Feist, G.W.; Linares-Casenave, J.; Fitzpatrick, M.S.; Schreck, C.B.; Doroshov, S.I.

    2001-01-01

    Recently, commercial aquaculture farms in Northern California have exposed gravid, cultured white sturgeon females to cold water (12 ?? 1??C) throughout the late phase of vitellogenesis and ovarian follicle maturation resulting in improved ovulation rates and egg quality. However, the optimum timing for transfer of broodfish to the cold water and the capacity of transferred broodfish to maintain reproductive competence over an extended time in cold water had not been evaluated. Gravid white sturgeon females that have been raised at water temperatures of 16-20??C were transported to either cold water (12 ?? 1??C; Group 1) in November 1997 or maintained in ambient water temperatures (10-19??C; Group 2) until early spring. In March 1998, half of the fish in Group 2 had regressed ovaries, but the remaining females had intact ovarian follicles and were transported to the cold water. Ovarian follicles and blood were collected from females until they reached the stage of spawning readiness (determined by germinal vesicle position and an oocyte maturation assay) or underwent ovarian regression. Exposure of gravid sturgeon females to ambient water temperatures (14.5 ?? 2.3??C, mean ?? S.D.) from October to March led to a decrease in plasma sex steroids and a high incidence of ovarian regression in fish with a more advanced stage of oocyte development. Transfer of females with intact ovarian follicles to cold water (12 ?? 1??C) in the fall or early spring resulted in normal ovarian development in the majority of females. Holding females in cold water does not seem to override their endogenous reproductive rhythms but extends their capacity to maintain oocyte maturational competence over a longer period of time. A temperature-sensitive phase in ovarian development may occur during the transition from vitellogenic growth to oocyte maturation, and the degree and timing of sensitivity to environmental temperature are dependent on the female's endogenous reproductive rhythm

  2. Chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures

    USGS Publications Warehouse

    Wang, Ning; Ingersoll, Christopher G.; Dorman, Rebecca A.; Brumbaugh, William G.; Mebane, Christopher A.; Kunz, James L.; Hardesty, Douglas K.

    2014-01-01

    Chronic toxicity of cadmium, copper, lead, or zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) was evaluated in water-only exposures started with newly hatched larvae or approximately 1-mo-old juveniles. The 20% effect concentration (EC20) for cadmium from the sturgeon tests was higher than the EC20 from the trout tests, whereas the EC20 for copper, lead, or zinc for the sturgeon were lower than those EC20s for the trout. When the EC20s from the present study were included in compiled toxicity databases for all freshwater species, species mean chronic value for white sturgeon was in a relatively low percentile of the species sensitivity distribution for copper (9th percentile) and in the middle percentile for cadmium (55th percentile), zinc (40th percentile), or lead (50th percentile). However, the species mean chronic value for rainbow trout was in a high percentile for copper, lead, and zinc (∼68th–82nd percentile), but in a low percentile for cadmium (23rd percentile). The trout EC20s for each of the 4 metals and the sturgeon EC20s for cadmium or lead were above US Environmental Protection Agency chronic ambient water quality criteria (AWQC) or Washington State chronic water quality standards (WQS), whereas the sturgeon EC20s for copper or zinc were approximately equal to or below the chronic AWQC and WQS. In addition, acute 50% effect concentrations (EC50s) for copper obtained in the first 4 d of the chronic sturgeon test were below the final acute value used to derive acute AWQC and below acute WQS for copper.

  3. Chronic sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to cadmium, copper, lead, or zinc in laboratory water-only exposures.

    PubMed

    Wang, Ning; Ingersoll, Christopher G; Dorman, Rebecca A; Brumbaugh, William G; Mebane, Christopher A; Kunz, James L; Hardesty, Doug K

    2014-10-01

    Chronic toxicity of cadmium, copper, lead, or zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) was evaluated in water-only exposures started with newly hatched larvae or approximately 1-mo-old juveniles. The 20% effect concentration (EC20) for cadmium from the sturgeon tests was higher than the EC20 from the trout tests, whereas the EC20 for copper, lead, or zinc for the sturgeon were lower than those EC20s for the trout. When the EC20s from the present study were included in compiled toxicity databases for all freshwater species, species mean chronic value for white sturgeon was in a relatively low percentile of the species sensitivity distribution for copper (9th percentile) and in the middle percentile for cadmium (55th percentile), zinc (40th percentile), or lead (50th percentile). However, the species mean chronic value for rainbow trout was in a high percentile for copper, lead, and zinc (∼68th-82nd percentile), but in a low percentile for cadmium (23rd percentile). The trout EC20s for each of the 4 metals and the sturgeon EC20s for cadmium or lead were above US Environmental Protection Agency chronic ambient water quality criteria (AWQC) or Washington State chronic water quality standards (WQS), whereas the sturgeon EC20s for copper or zinc were approximately equal to or below the chronic AWQC and WQS. In addition, acute 50% effect concentrations (EC50s) for copper obtained in the first 4 d of the chronic sturgeon test were below the final acute value used to derive acute AWQC and below acute WQS for copper.

  4. Acute sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to copper, cadmium, or zinc in water-only laboratory exposures

    PubMed Central

    Calfee, Robin D; Little, Edward E; Puglis, Holly J; Scott, Erinn; Brumbaugh, William G; Mebane, Christopher A

    2014-01-01

    The acute toxicity of cadmium, copper, and zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) were determined for 7 developmental life stages in flow-through water-only exposures. Metal toxicity varied by species and by life stage. Rainbow trout were more sensitive to cadmium than white sturgeon across all life stages, with median effect concentrations (hardness-normalized EC50s) ranging from 1.47 µg Cd/L to 2.62 µg Cd/L with sensitivity remaining consistent during later stages of development. Rainbow trout at 46 d posthatch (dph) ranked at the 2nd percentile of a compiled database for Cd species sensitivity distribution with an EC50 of 1.46 µg Cd/L and 72 dph sturgeon ranked at the 19th percentile (EC50 of 3.02 µg Cd/L). White sturgeon were more sensitive to copper than rainbow trout in 5 of the 7 life stages tested with biotic ligand model (BLM)-normalized EC50s ranging from 1.51 µg Cu/L to 21.9 µg Cu/L. In turn, rainbow trout at 74 dph and 95 dph were more sensitive to copper than white sturgeon at 72 dph and 89 dph, indicating sturgeon become more tolerant in older life stages, whereas older trout become more sensitive to copper exposure. White sturgeon at 2 dph, 16 dph, and 30 dph ranked in the lower percentiles of a compiled database for copper species sensitivity distribution, ranking at the 3rd (2 dph), 5th (16 dph), and 10th (30 dph) percentiles. White sturgeon were more sensitive to zinc than rainbow trout for 1 out of 7 life stages tested (2 dph with an biotic ligand model–normalized EC50 of 209 µg Zn/L) and ranked in the 1st percentile of a compiled database for zinc species sensitivity distribution. Environ Toxicol Chem 2014;33:2259–2272. © 2014. The Authors. This article is a US government work and, as such, is in the public domain in the United States of America. Environmental Toxicology and Chemistry published byWiley Periodicals, Inc. on behalf of SETAC. This is an open access article

  5. Acute sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to copper, cadmium, or zinc in water-only laboratory exposures

    USGS Publications Warehouse

    Calfee, Robin D.; Little, Edward E.; Puglis, Holly J.; Scott, Erinn L.; Brumbaugh, William G.; Mebane, Christopher A.

    2014-01-01

    The acute toxicity of cadmium, copper, and zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) were determined for 7 developmental life stages in flow-through water-only exposures. Metal toxicity varied by species and by life stage. Rainbow trout were more sensitive to cadmium than white sturgeon across all life stages, with median effect concentrations (hardness-normalized EC50s) ranging from 1.47 µg Cd/L to 2.62 µg Cd/L with sensitivity remaining consistent during later stages of development. Rainbow trout at 46 d posthatch (dph) ranked at the 2nd percentile of a compiled database for Cd species sensitivity distribution with an EC50 of 1.46 µg Cd/L and 72 dph sturgeon ranked at the 19th percentile (EC50 of 3.02 µg Cd/L). White sturgeon were more sensitive to copper than rainbow trout in 5 of the 7 life stages tested with biotic ligand model (BLM)-normalized EC50s ranging from 1.51 µg Cu/L to 21.9 µg Cu/L. In turn, rainbow trout at 74 dph and 95 dph were more sensitive to copper than white sturgeon at 72 dph and 89 dph, indicating sturgeon become more tolerant in older life stages, whereas older trout become more sensitive to copper exposure. White sturgeon at 2 dph, 16 dph, and 30 dph ranked in the lower percentiles of a compiled database for copper species sensitivity distribution, ranking at the 3rd (2 dph), 5th (16 dph), and 10th (30 dph) percentiles. White sturgeon were more sensitive to zinc than rainbow trout for 1 out of 7 life stages tested (2 dph with an biotic ligand model–normalized EC50 of 209 µg Zn/L) and ranked in the 1st percentile of a compiled database for zinc species sensitivity distribution.

  6. Acute sensitivity of white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) to copper, cadmium, or zinc in water-only laboratory exposures.

    PubMed

    Calfee, Robin D; Little, Edward E; Puglis, Holly J; Scott, Erinn; Brumbaugh, William G; Mebane, Christopher A

    2014-10-01

    The acute toxicity of cadmium, copper, and zinc to white sturgeon (Acipenser transmontanus) and rainbow trout (Oncorhynchus mykiss) were determined for 7 developmental life stages in flow-through water-only exposures. Metal toxicity varied by species and by life stage. Rainbow trout were more sensitive to cadmium than white sturgeon across all life stages, with median effect concentrations (hardness-normalized EC50s) ranging from 1.47 µg Cd/L to 2.62 µg Cd/L with sensitivity remaining consistent during later stages of development. Rainbow trout at 46 d posthatch (dph) ranked at the 2nd percentile of a compiled database for Cd species sensitivity distribution with an EC50 of 1.46 µg Cd/L and 72 dph sturgeon ranked at the 19th percentile (EC50 of 3.02 µg Cd/L). White sturgeon were more sensitive to copper than rainbow trout in 5 of the 7 life stages tested with biotic ligand model (BLM)-normalized EC50s ranging from 1.51 µg Cu/L to 21.9 µg Cu/L. In turn, rainbow trout at 74 dph and 95 dph were more sensitive to copper than white sturgeon at 72 dph and 89 dph, indicating sturgeon become more tolerant in older life stages, whereas older trout become more sensitive to copper exposure. White sturgeon at 2 dph, 16 dph, and 30 dph ranked in the lower percentiles of a compiled database for copper species sensitivity distribution, ranking at the 3rd (2 dph), 5th (16 dph), and 10th (30 dph) percentiles. White sturgeon were more sensitive to zinc than rainbow trout for 1 out of 7 life stages tested (2 dph with an biotic ligand model-normalized EC50 of 209 µg Zn/L) and ranked in the 1st percentile of a compiled database for zinc species sensitivity distribution.

  7. Research tools to investigate movements, migrations, and life history of sturgeons (Acipenseridae), with an emphasis on marine-oriented populations.

    PubMed

    Nelson, Troy C; Doukakis, Phaedra; Lindley, Steven T; Schreier, Andrea D; Hightower, Joseph E; Hildebrand, Larry R; Whitlock, Rebecca E; Webb, Molly A H

    2013-01-01

    Worldwide, sturgeons (Acipenseridae) are among the most endangered fishes due to habitat degradation, overfishing, and inherent life history characteristics (long life span, late maturation, and infrequent spawning). As most sturgeons are anadromous, a considerable portion of their life history occurs in estuarine and marine environments where they may encounter unique threats (e.g., interception in non-target fisheries). Of the 16 marine-oriented species, 12 are designated as Critically Endangered by the IUCN, and these include species commercially harvested. We review important research tools and techniques (tagging, electronic tagging, genetics, microchemistry, observatory) and discuss the comparative utility of these techniques to investigate movements, migrations, and life-history characteristics of sturgeons. Examples are provided regarding what the applications have revealed regarding movement and migration and how this information can be used for conservation and management. Through studies that include Gulf (Acipenser oxyrinchus desotoi) and Green Sturgeon (A. medirostris), we illustrate what is known about well-studied species and then explore lesser-studied species. A more complete picture of migration is available for North American sturgeon species, while European and Asian species, which are among the most endangered sturgeons, are less understood. We put forth recommendations that encourage the support of stewardship initiatives to build awareness and provide key information for population assessment and monitoring. PMID:23990959

  8. Research Tools to Investigate Movements, Migrations, and Life History of Sturgeons (Acipenseridae), with an Emphasis on Marine-Oriented Populations

    PubMed Central

    Nelson, Troy C.; Doukakis, Phaedra; Lindley, Steven T.; Schreier, Andrea D.; Hightower, Joseph E.; Hildebrand, Larry R.; Whitlock, Rebecca E.; Webb, Molly A. H.

    2013-01-01

    Worldwide, sturgeons (Acipenseridae) are among the most endangered fishes due to habitat degradation, overfishing, and inherent life history characteristics (long life span, late maturation, and infrequent spawning). As most sturgeons are anadromous, a considerable portion of their life history occurs in estuarine and marine environments where they may encounter unique threats (e.g., interception in non-target fisheries). Of the 16 marine-oriented species, 12 are designated as Critically Endangered by the IUCN, and these include species commercially harvested. We review important research tools and techniques (tagging, electronic tagging, genetics, microchemistry, observatory) and discuss the comparative utility of these techniques to investigate movements, migrations, and life-history characteristics of sturgeons. Examples are provided regarding what the applications have revealed regarding movement and migration and how this information can be used for conservation and management. Through studies that include Gulf (Acipenser oxyrinchus desotoi) and Green Sturgeon (A. medirostris), we illustrate what is known about well-studied species and then explore lesser-studied species. A more complete picture of migration is available for North American sturgeon species, while European and Asian species, which are among the most endangered sturgeons, are less understood. We put forth recommendations that encourage the support of stewardship initiatives to build awareness and provide key information for population assessment and monitoring. PMID:23990959

  9. Research tools to investigate movements, migrations, and life history of sturgeons (Acipenseridae), with an emphasis on marine-oriented populations.

    PubMed

    Nelson, Troy C; Doukakis, Phaedra; Lindley, Steven T; Schreier, Andrea D; Hightower, Joseph E; Hildebrand, Larry R; Whitlock, Rebecca E; Webb, Molly A H

    2013-01-01

    Worldwide, sturgeons (Acipenseridae) are among the most endangered fishes due to habitat degradation, overfishing, and inherent life history characteristics (long life span, late maturation, and infrequent spawning). As most sturgeons are anadromous, a considerable portion of their life history occurs in estuarine and marine environments where they may encounter unique threats (e.g., interception in non-target fisheries). Of the 16 marine-oriented species, 12 are designated as Critically Endangered by the IUCN, and these include species commercially harvested. We review important research tools and techniques (tagging, electronic tagging, genetics, microchemistry, observatory) and discuss the comparative utility of these techniques to investigate movements, migrations, and life-history characteristics of sturgeons. Examples are provided regarding what the applications have revealed regarding movement and migration and how this information can be used for conservation and management. Through studies that include Gulf (Acipenser oxyrinchus desotoi) and Green Sturgeon (A. medirostris), we illustrate what is known about well-studied species and then explore lesser-studied species. A more complete picture of migration is available for North American sturgeon species, while European and Asian species, which are among the most endangered sturgeons, are less understood. We put forth recommendations that encourage the support of stewardship initiatives to build awareness and provide key information for population assessment and monitoring.

  10. Spawning and rearing habitat use by white sturgeons in the Columbia River downstream from McNary Dam

    SciTech Connect

    Parsley, M.J.; Beckman, L.G. )

    1993-03-01

    Spawning and rearing habitats used by white sturgeons Acipenser transmontanus were described from water temperature, depth, and velocity measurements and substrate types present at sites where eggs, larvae, young-of-the-year, and juveniles (ages 1-7) were collected. Spawning and egg incubation occurred in the swiftest water available (mean water column velocity, 0.8-2.8 m/s), which was within 8 km downstream from each of the four main-stem Columbia River dams in our study area. Substrates where spawning occurred mainly cobble, boulder, and bedrock. Yolk-sac larvae were transported by the river currents from spawning areas into deeper areas with lower water velocities and finer substrates. Young-of-the-year white sturgeons were found at depths of 9-57 m, at mean water column velocities of 0.6 m/s and less, and over substrates of hard clay, mud and silt, sand, gravel, and cobble. Juvenile fish were found at depths of 2-58 m, at mean water column velocities of 1.2 m/s and less, and over substrates of hard clay, mud and silt, sand, gravel, cobble, boulder, and bedrock. 38 refs., 9 figs., 2 tabs.

  11. White Sturgeon Mitigation and Restoration in the Columbia and Snake Rivers Upstream from Bonneville Dam; 1998-1999 Annual Report.

    SciTech Connect

    Ward, David L.

    2000-12-01

    The authors report on their progress from April 1998 through March 1999 on determining the effects of mitigative measures on productivity of white sturgeon populations in the Columbia River downstream from McNary Dam, and on determining the status and habitat requirements of white sturgeon populations in the Columbia and Snake rivers upstream from McNary Dam. The study is a cooperative effort by the Oregon Department of Fish and Wildlife (ODFW; Report A), Washington Department of Fish and Wildlife (WDFW; Report B), U.S. Geological Survey Biological Resources Division (USGS; Report C), U.S. Fish and Wildlife Service (USFWS; Report D), Columbia River Inter-Tribal Fish Commission (CRITFC; Report E), and the University of Idaho (UI; Report F). This is a multi-year study with many objectives requiring more than one year to complete. Therefore, findings from a given year may be part of more significant findings yet to be reported. Highlights of results of our work from April 1998 through March 1999 are given.

  12. White Sturgeon Mitigation and Restoration in the Columbia and Snake Rivers Upstream from Bonneville Dam, 1999-2000 Annual Report.

    SciTech Connect

    Ward, David L.

    2001-04-01

    We report on our progress from April 1999 through March 2000 on determining the effects of mitigative measures on productivity of white sturgeon populations in the Columbia River downstream from McNary Dam, and on determining the status and habitat requirements of white sturgeon populations in the Columbia and Snake rivers upstream from McNary Dam. The study is a cooperative effort by the Oregon Department of Fish and Wildlife (ODFW; Report A), Washington Department of Fish and Wildlife (WDFW; Report B), U.S. Geological Survey Biological Resources Division (USGS; Report C), Columbia River Inter-Tribal Fish Commission (CRITFC; Report D), and the U.S. Fish and Wildlife Service (USFWS; Report E). This is a multi-year study with many objectives requiring more than one year to complete. Therefore, findings from a given year may be part of more significant findings yet to be reported. Highlights of results of our work from April 1999 through March 2000 are given.

  13. White Sturgeon Mitigation and Restoration in the Columbia and Snake Rivers Upstream from Bonneville Dam; 2000-2001 Annual Report.

    SciTech Connect

    Kern, J. Chris; Ward, David L.; Farr, Ruth A.

    2002-02-01

    We report on our progress from April 2000 through March 2001 on determining the effects of mitigative measures on productivity of white sturgeon populations in the Columbia River downstream from McNary Dam, and on determining the status and habitat requirements of white sturgeon populations in the Columbia and Snake rivers upstream from McNary Dam. The study is a cooperative effort by the Oregon Department of Fish and Wildlife (ODFW; Report A), Washington Department of Fish and Wildlife (WDFW; Report B), U.S. Geological Survey Biological Resources Division (USGS; Report C), Columbia River Inter-Tribal Fish Commission (CRITFC; Report D), the U.S. Fish and Wildlife Service (USFWS; Report E), and Oregon State University (OSU; Report F). This is a multi-year study with many objectives requiring more than one year to complete; therefore, findings from a given year may be part of more significant findings yet to be reported. Highlights of results of our work from April 2000 through March 2001 are listed.

  14. Maintaining tissue selenium species distribution as a potential defense mechanism against methylmercury toxicity in juvenile white sturgeon (Acipenser transmontanus).

    PubMed

    Huang, Susie Shih-Yin; Hung, Silas S O; Chan, Hing Man

    2014-11-01

    Selenium (Se) has been shown to antagonize mercury (Hg) toxicity. We have previously demonstrated that orally intubated selenomethionine (SeMet) and methylmercury (MeHg) reduced tissue Se accumulation, as well as blood and kidney Hg concentrations in juvenile white sturgeon (Acipenser transmontanus). However, the form of Se accumulated is not known. In this study, three organoseleniums: selenocysteine (Sec), Se-methyl-selenocysteine (MSeCys), and SeMet and two inorganic Se species: selenate and selenite were determined and quantified in the blood at different post-intubation periods (12, 24, 48h) and in the muscle, liver, and kidneys at 48h in white sturgeon orally intubated with a single dose of control (carrier), SeMet (500μg Se/kg body weight; BW), MeHg (850μg Hg/kg BW), and both (Se+Hg; at 500μg Se/kg and 850μg Hg/kg BW). When only SeMet was intubated, the accumulative/unmodified pathway took precedent in the blood, white muscle, liver, and kidneys. In the presence of MeHg, however, active metabolic transformation and de novo synthesis of biologically active Se forms are seen in the liver and kidneys, as indicated by a gradual increase in blood Sec:SeMet ratios and Se metabolites. In the white muscle, mobilization of endogenous Se storage by MeHg is supported by the absence of tissue SeMet and detectable levels of blood SeMet. In contrast, co-intubation with SeMet increased muscle SeMet. The high levels of unknown Se metabolites and detectable levels of selenite in the kidney reflect its role as the major excretory organ for Se. Selenium metabolism is highly regulated in the kidneys, as Se speciation was not affected by MeHg or by its co-intubation with SeMet. In the Se+Hg group, the proportion of SeMet in the liver has decreased to nearly 1/8th of that of the SeMet only group, resulting in a more similar selenocompound distribution profile to that of the MeHg only group. This is likely due to the increased need for Se metabolites necessary for Me

  15. Status and Habitat Requirements of the White Sturgeon Populations in the Columbia River Downstream from McNary Dam Volume II; Supplemental Papers and Data Documentation, 1986-1992 Final Report.

    SciTech Connect

    Beamesderfer, Raymond C.; Nigro, Anthony A.

    1995-01-01

    This is the final report for research on white sturgeon Acipenser transmontanus from 1986--92 and conducted by the National Marine Fisheries Service (NMFS), Oregon Department of Fish and Wildlife (ODFW), US Fish and Wildlife Service (USFWS), and Washington Department of Fisheries (WDF). Findings are presented as a series of papers, each detailing objectives, methods, results, and conclusions for a portion of this research. This volume includes supplemental papers which provide background information needed to support results of the primary investigations addressed in Volume 1. This study addresses measure 903(e)(1) of the Northwest Power Planning Council's 1987 Fish and Wildlife Program that calls for ''research to determine the impact of development and operation of the hydropower system on sturgeon in the Columbia River Basin.'' Study objectives correspond to those of the ''White Sturgeon Research Program Implementation Plan'' developed by BPA and approved by the Northwest Power Planning Council in 1985. Work was conducted on the Columbia River from McNary Dam to the estuary.

  16. White Sturgeon Management Plan in the Snake River between Lower Granite and Hells Canyon Dams; Nez Perce Tribe, 1997-2005 Final Report.

    SciTech Connect

    Nez Perce Tribe Resources Management Staff,

    2005-09-01

    White sturgeon in the Hells Canyon reach (HCR) of the Snake River are of cultural importance to the Nez Perce Tribe. However, subsistence and ceremonial fishing opportunities have been severely limited as a result of low numbers of white sturgeon in the HCR. Hydrosystem development in the Columbia River Basin has depressed numbers and productivity of white sturgeon in the HCR by isolating fish in impounded reaches of the basin, restricting access to optimal rearing habitats, reducing the anadromous forage base, and modifying early life-history habitats. Consequently, a proactive management plan is needed to mitigate for the loss of white sturgeon production in the HCR, and to identify and implement feasible measures that will restore and rebuild the white sturgeon population to a level that sustains viability and can support an annual harvest. This comprehensive and adaptive management plan describes the goals, objectives, strategies, actions, and expected evaluative timeframes for restoring the white sturgeon population in the HCR. The goal of this plan, which is to maintain a viable, persistent population that can support a sustainable fishery, is supported by the following objectives: (1) a natural, stable age structure comprising both juveniles and a broad spectrum of spawning age-classes; (2) stable or increasing numbers of both juveniles and adults; (3) consistent levels of average recruitment to ensure future contribution to reproductive potential; (4) stable genetic diversity comparable to current levels; (5) a minimum level of abundance of 2,500 adults to minimize extinction risk; and (6) provision of an annual sustainable harvest of 5 kg/ha. To achieve management objectives, potential mitigative actions were developed by a Biological Risk Assessment Team (BRAT). Identified strategies and actions included enhancing growth and survival rates by restoring anadromous fish runs and increasing passage opportunities for white sturgeon, reducing mortality rates

  17. Effects of Mitigation Measures on Productivity of the White Sturgeon Populations in the Columbia River Downstream from McNary Dam, and Status and Habitat Requirements of White Sturgeon Populations in the Columbia and Snake Rivers Upstream from McNary Dam, 1992-1993 Annual Report.

    SciTech Connect

    Beamesdorfer, Raymond C.; Nigro, Anthony A.

    1993-12-01

    We report on our progress from April 1992-March 1993 in research on white sturgeon in the lower Columbia River. The study began in July 1986 and progress through 1992 was summarized in a comprehensive report in 2 volumes (Beamesderfer and Nigro 1993a, 1993b). This report details activities during the first year of Phase II of this sturgeon research. In Phase I, we assessed the status and habitat requirements of the white sturgeon populations in the Columbia River downstream from McNary Dam. Phase II will examine the effects on white sturgeon productivity of mitigative measures recommended in Phase I. The status and habitat requirements of white sturgeon populations upstream from McNary Dam will also be examined in Phase II. The study is a cooperative effort by the Oregon Department of Fish and Wildlife, Washington Department of Fisheries, U.S. Fish and Wildlife Service, and National Marine Fisheries Service. Work during the past year has focused on: (1) analysis of results of limited sampling conducted in 1992, (2) submission of Phase I results to the peer-review literature to ensure widespread dissemination, clarity of presentation, and credibility of findings, and (3) preparations for additional field work in 1993. In report sections A to D, each agency reports 1992 results if applicable and the current status of manuscripts. Results of field work conducted in 1993 will be reported in the 1994 annual report.

  18. Status and Habitat Requirements of White Sturgeon Populations in the Columbia River Downstream from McNary Dam, 1986-1987 Annual Report.

    SciTech Connect

    McCabe, Jr., George T.; Beckman, Lance G.; Kreitman, Gayle

    1987-06-01

    Measure 804(e)(8) of the Northwest Power Planning Council (NPPC) Fish and Wildlife Program states that Bonneville Power Administration (BPA) ''shall fund research to determine the impacts of development and operation of the hydroelectric power system on sturgeon in the Columbia River Basin...'' In June 1985, BPA sponsored a workshop to define and list in priority order research needs in the basin (Fickeisen 1985a). In December 1985, BPA submitted a research program implementation plan (Fickeisen 1985b) to the NPPC. The purpose of the plan is to provide guidance for conducting research necessary to address four objectives identified by regional fishery interests for protecting, mitigating and enhancing white sturgeon populations in the Columbia River basin. The plan's objectives are: (1) Assess the current status of Columbia River basin white sturgeon stocks. (2) Provide the basis to evaluate the need for protection, mitigation and enhancement of white sturgeon in the Columbia River system. (3) Provide information that can be used to evaluate potential methods of protection, mitigation and enhancement of existing stocks. (4) Provide tools to assess the effectiveness of protection, mitigation and enhancement efforts.

  19. Status and Habitat Requirements of the White Sturgeon Populations in the Columbia River Downstream from McNary Dam, 1990-1991 Annual Report.

    SciTech Connect

    Nigro, Anthony A.

    1991-09-01

    We report on our effort from April 1990 to March 1991 to describe the life history and population dynamics of white sturgeon Acipenser transmontanus in.John Day Reservoir. We set 1188 set lines and 26 gill nets. We caught 623 white sturgeon with set lines and 236 with gill nets. Catch per unit effort was much higher in areas near the tailrace than in downstream sites. Our setlines were size selective. We recaptured 3 fish released in John Day Reservoir in 1989 and 28 fish released in 1990. Sport and commercial fishermen recovered 62 tags from fish we tagged in Bonneville, The Dalles and John Day reservoirs, 1987-1990. We observed extensive movements of marked sturgeon within the reservoirs. We completed aging of available samples from all three reservoirs from 1987-1990. We aged fish as old as 46 years. Bone marks were observed on 74 of 78 fish previously injected with oxytetracycline and annulus formation was generally complete after June. We estimated parameters in a length-weight equation. About 1.5% of the female white sturgeon we examined to date had early or late vitellogenic eggs and would be expected to spawn the following year.

  20. Simulation of flow and sediment transport in the white sturgeon spawning habitat of the Kootenai River near Bonners Ferry, Idaho

    USGS Publications Warehouse

    Berenbrock, Charles; Bennett, James P.

    2005-01-01

    Characterization of sediment transport of the Kootenai River in the white sturgeon spawning reach is needed by the Kootenai River White Sturgeon Recovery Team to predict sediment-transport conditions that improve spawning conditions for the white sturgeon (Acipenser transmontanus) in the Kootenai River near Bonners Ferry, Idaho. The decreasing population and spawning failure of the white sturgeon has led to much concern. Few wild juvenile sturgeon are found in the river today. The Kootenai River begins in British Columbia, Canada, and flows through Montana, Idaho, and back into British Columbia. A 15-mile reach of the Kootenai River in Idaho was studied, including the white sturgeon spawning reach that has been designated as a critical habitat near Bonners Ferry, Idaho, and a 1-mile long side channel around the western side of Shorty Island. A one-dimensional sediment-transport model of the study reach was developed, calibrated, and used to simulate the response of the hydraulic and sediment system to varying discharges and water-surface elevations. The model comprises 79 cross sections, most of which came from a previous river survey conducted in 2002-03. Bed-sediment samples collected in 2002 and additional samples collected for this study in 2004 were used in the model. The model was calibrated to discharge and water-surface elevations at two U.S. Geological Survey gaging stations. The model also was calibrated to suspended-sediment discharge at several sites in the study reach. The calibrated model was used to simulate six different management alternatives to assess erosion and deposition under varying hydraulic conditions at the end of 21 days of simulation. Alternative 1 was simulated with a discharge of 6,000 cubic feet per second (ft3/s), alternative 2 with 20,000 ft3/s, alternative 3 with 40,000 ft3/s, and alternatives 4 through 6 with 60,000 ft3/s and represents low to high discharges in the river since the construction of Libby Dam. Sediment deposition

  1. Simulation of hydraulic characteristics in the white sturgeon spawning habitat of the Kootenai River near Bonners Ferry, Idaho

    USGS Publications Warehouse

    Berenbrock, Charles

    2005-01-01

    Hydraulic characterization of the Kootenai River, especially in the white sturgeon spawning habitat reach, is needed by the Kootenai River White Sturgeon Recovery Team to promote hydraulic conditions that improve spawning conditions for the white sturgeon (Acipenser transmontanus) in the Kootenai River. The decreasing population and spawning failure of white sturgeon has led to much concern. Few wild juvenile sturgeons are found in the river today. Determining the location of the transition between backwater and free-flowing water in the Kootenai River is a primary focus for biologists who believe that hydraulic changes at the transition affect the location where the sturgeon choose to spawn. The Kootenai River begins in British Columbia, Canada, and flows through Montana, Idaho, and back into British Columbia. The 65.6-mile reach of the Kootenai River in Idaho was studied. The study area encompasses the white sturgeon spawning reach that has been designated as a critical habitat. A one-dimensional hydraulic-flow model of the study reach was developed, calibrated, and used to develop relations between hydraulic characteristics and water-surface elevation, discharge, velocity, and backwater extent. The model used 164 cross sections, most of which came from a previous river survey conducted in 2002-03. The model was calibrated to water-surface elevations at specific discharges at five gaging stations. Calibrated water-surface elevations ranged from about 1,743 to about 1,759 feet, and discharges used in calibration ranged from 5,000 to 47,500 cubic feet per second. Model calibration was considered acceptable when the difference between measured and simulated water-surface elevations was ?0.15 foot or less. Measured and simulated average velocities also were compared. These comparisons indicated agreement between measured and simulated values. The location of the transition between backwater and free-flowing water was determined using the calibrated model. The model

  2. Acute toxicity of copper, lead, cadmium, and zinc to early life stages of white sturgeon (Acipenser transmontanus) in laboratory and Columbia River water.

    PubMed

    Vardy, David W; Santore, Robert; Ryan, Adam; Giesy, John P; Hecker, Markus

    2014-01-01

    Populations of white sturgeon (Acipenser transmontanus) are in decline in North America. This is attributed, primarily, to poor recruitment, and white sturgeon are listed as threatened or endangered in several parts of British Columbia, Canada, and the United States. In the Columbia River, effects of metals have been hypothesized as possible contributing factors. Previous work has demonstrated that early life stage white sturgeon are particularly sensitive to certain metals, and concerns over the level of protectiveness of water quality standards are justified. Here we report results from acute (96-h) toxicity tests for copper (Cu), cadmium (Cd), zinc (Zn), and lead (Pb) from parallel studies that were conducted in laboratory water and in the field with Columbia River water. Water effect ratios (WERs) and sensitivity parameters (i.e., median lethal accumulations, or LA50s) were calculated to assess relative bioavailability of these metals in Columbia River water compared to laboratory water, and to elucidate possible differences in sensitivity of early life stage white sturgeon to the same concentrations of metals when tested in the different water sources. For Cu and Pb, white sturgeon toxicity tests were initiated at two life stages, 8 and 40 days post-hatch (dph), and median lethal concentrations (LC50s) ranged between 9-25 μg Cu/L and 177-1,556 μg Pb/L. LC50s for 8 dph white sturgeon exposed to Cd in laboratory water and river water were 14.5 and 72 μg/L, respectively. Exposure of 8 dph white sturgeon to Zn in laboratory and river water resulted in LC50s of 150 and 625 μg/L, respectively. Threshold concentrations were consistently less in laboratory water compared with river water, and as a result, WERs were greater than 1 in all cases. In addition, LA50s were consistently greater in river water exposures compared with laboratory exposures in all paired tests. These results, in combination with results from the biotic ligand model, suggest that the observed

  3. Effects of Mitigative Measures on Productivity of White Sturgeon Populations in the Columbia River Downstream from McNary Dam; Determine Status and Habitat Requirements of White Sturgeon Populations in the Columbia and Snake Rivers Upstream from McNary Dam, 1995-1996 Annual Report.

    SciTech Connect

    Rien, Thomas A.; Beiningen, Kirk T.

    1997-07-01

    This project began in July 1986 and is a cooperative effort of federal, state, and tribal fisheries entities to determine (1) the status and habitat requirements, and (2) effects of mitigative measures on productivity of white sturgeon populations in the lower Colombia and Snake rivers.

  4. Toxicity of smelter slag-contaminated sediments from Upper Lake Roosevelt and associated metals to early life stage White Sturgeon (Acipenser transmontanus Richardson, 1836)

    USGS Publications Warehouse

    Little, E.E.; Calfee, R.D.; Linder, G.

    2014-01-01

    The toxicity of five smelter slag-contaminated sediments from the upper Columbia River and metals associated with those slags (cadmium, copper, zinc) was evaluated in 96-h exposures of White Sturgeon (Acipenser transmontanus Richardson, 1836) at 8 and 30 days post-hatch. Leachates prepared from slag-contaminated sediments were evaluated for toxicity. Leachates yielded a maximum aqueous copper concentration of 11.8 μg L−1 observed in sediment collected at Dead Man's Eddy (DME), the sampling site nearest the smelter. All leachates were nonlethal to sturgeon that were 8 day post-hatch (dph), but leachates from three of the five sediments were toxic to fish that were 30 dph, suggesting that the latter life stage is highly vulnerable to metals exposure. Fish maintained consistent and prolonged contact with sediments and did not avoid contaminated sediments when provided a choice between contaminated and uncontaminated sediments. White Sturgeon also failed to avoid aqueous copper (1.5–20 μg L−1). In water-only 96-h exposures of 35 dph sturgeon with the three metals, similar toxicity was observed during exposure to water spiked with copper alone and in combination with cadmium and zinc. Cadmium ranging from 3.2 to 41 μg L−1 or zinc ranging from 21 to 275 μg L−1 was not lethal, but induced adverse behavioral changes including a loss of equilibrium. These results suggest that metals associated with smelter slags may pose an increased exposure risk to early life stage sturgeon if fish occupy areas contaminated by slags.

  5. White Sturgeon Mitigation and Restoration in the Columbia and Snake Rivers Upstream from Bonneville Dam; Annual Progress Report, April 2007 - March 2008.

    SciTech Connect

    Mallette, Christine

    2009-07-28

    We report on our progress from April 2007 through March 2008 on determining the effects of mitigative measures on productivity of white sturgeon populations in the Columbia River downstream from McNary Dam, and on determining the status and habitat requirements of white sturgeon populations in the Columbia and Snake rivers upstream from McNary Dam. The study is a cooperative effort by the Oregon Department of Fish and Wildlife (ODFW; Report A), Washington Department of Fish and Wildlife (WDFW; Report B), Columbia River Inter-Tribal Fish Commission (CRITFC; Report C), and Montana State University (MSU; Report D). This is a multi-year study with many objectives requiring more than one year to complete; therefore, findings from a given year may be part of more significant findings yet to be reported.

  6. Confirmation of ovarian homogeneity in post-vitellogenic cultured white sturgeon, Acipenser transmontanus.

    PubMed

    Talbott, Mariah J; Servid, Sarah A; Cavinato, Anna G; Van Eenennaam, Joel P; Doroshov, Serge I; Struffenegger, Peter; Webb, Molly A H

    2014-02-01

    Assessing stage of oocyte maturity in female sturgeon by calculating oocyte polarization index (PI) is a necessary tool for both conservation propagation managers and caviar producers to know when to hormonally induce spawning. We tested the assumption that sampling ovarian follicles from one section of one ovary is sufficient for calculating an oocyte PI representative of oocyte maturity for an individual animal. Short-wavelength near-infrared spectroscopy (SW-NIR) scans were performed on three positions per ovary for five fish prior to caviar harvest. Samples of ovarian follicles were subsequently taken from the exact location of the SW-NIR scans for calculation of oocyte PI and follicle diameter. Oocyte PI was statistically different though not biologically relevant within an ovary and between ovaries in four of five fish. Follicle diameter was statistically different but not biologically relevant within an ovary in three of five fish. There were no differences in follicle diameter between ovaries. No statistical differences were observed between SW-NIR spectra collected at different locations within an ovary or between ovaries. These results emphasize the importance of utilizing both oocyte PI measurement and progesterone-induced oocyte maturation assays while deciding when to hormonally induce spawning in sturgeon females.

  7. Indexing the relative abundance of age-0 white sturgeons in an impoundment of the lower Columbia River from highly skewed trawling data

    USGS Publications Warehouse

    Counihan, T.D.; Miller, A.I.; Parsley, M.J.

    1999-01-01

    The development of recruitment monitoring programs for age-0 white sturgeons Acipenser transmontanus is complicated by the statistical properties of catch-per-unit-effort (CPUE) data. We found that age-0 CPUE distributions from bottom trawl surveys violated assumptions of statistical procedures based on normal probability theory. Further, no single data transformation uniformly satisfied these assumptions because CPUE distribution properties varied with the sample mean (??(CPUE)). Given these analytic problems, we propose that an additional index of age-0 white sturgeon relative abundance, the proportion of positive tows (Ep), be used to estimate sample sizes before conducting age-0 recruitment surveys and to evaluate statistical hypothesis tests comparing the relative abundance of age-0 white sturgeons among years. Monte Carlo simulations indicated that Ep was consistently more precise than ??(CPUE), and because Ep is binomially rather than normally distributed, surveys can be planned and analyzed without violating the assumptions of procedures based on normal probability theory. However, we show that Ep may underestimate changes in relative abundance at high levels and confound our ability to quantify responses to management actions if relative abundance is consistently high. If data suggest that most samples will contain age-0 white sturgeons, estimators of relative abundance other than Ep should be considered. Because Ep may also obscure correlations to climatic and hydrologic variables if high abundance levels are present in time series data, we recommend ??(CPUE) be used to describe relations to environmental variables. The use of both Ep and ??(CPUE) will facilitate the evaluation of hypothesis tests comparing relative abundance levels and correlations to variables affecting age-0 recruitment. Estimated sample sizes for surveys should therefore be based on detecting predetermined differences in Ep, but data necessary to calculate ??(CPUE) should also be

  8. Columbia River White Sturgeon (Acipenser Transmontanus) Early Life History and Genertics Study, August 1, 1984 to December 31, 1985 Final Report.

    SciTech Connect

    Brannon, Ernest L.

    1985-12-01

    Research on Columbia River white sturgeon has been directed at their early life history as it may apply to production and enhancement strategies for management of the species. The river environment in which sturgeon historically migrated, spawned, and reared has changed through development. Habitat changes are expected to precipitate genetic changes in the fish, as well as reduce the fitness in populations. Genetic analysis of samples taken from various locations over the length of the Columbia River have indicated that observed gene frequencies in all areas sampled were not in Hardy-Weinburg equilibrium, which could suggest that the general population is experiencing perturbation in the system. Analysis thus far has exposed few differences between samples from the lower, middle, and upper portions of the system. Allelic differences were identified in fish from the Roosevelt Lake, which may be evidence of unique characteristics among fish from that general area.

  9. Recovery of white sturgeon populations through natural production: Understanding the influence of abiotic and biotic factors on spawning and subsequent recruitment

    USGS Publications Warehouse

    Parsley, M.J.; Anders, P.J.; Miller, A.I.; Beckman, L.G.; McCabe, G.T.

    2002-01-01

    Recovery or maintenance of sturgeon populations through natural production in perturbed rivers requires adequate knowledge of the abiotic and biotic factors that influence spawning and cause mortality of embryonic, larval, and juvenile life stages. Although it is known that year-class strength of white sturgeon Acipenser transmontanus is determined within 2-3 months after spawning, little is known about specific causes of mortality to early life stages during this period. Initial spawning success is critical in the development of a strong year-class, and maximized recruitment may be dependent upon water temperature and the availability of optimal in-river habitat. Analyses have shown that increased river discharge combined with suitable water temperatures during spawning, egg incubation, yolk sac larvae dispersal, and first exogenous feeding result in greater recruitment. However, little is known about the importance of other variables, such as food availability or losses due to predation that influence year-class strength. ?? 2002 by the American Fisheries Society.

  10. Simultaneous extraction and cleanup of high-lipid organs from white sturgeon (Acipenser transmontanus) for multiple legacy and emerging organic contaminants using QuEChERS sample preparation.

    PubMed

    Morrison, Shane A; Sieve, Kristal K; Ratajczak, Robert E; Bringolf, Robert B; Belden, Jason B

    2016-01-01

    The objective of this research was to utilize the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method to extract a broad range of persistent organic pollutants from sturgeon organs (liver and gonad) as indicators of exposure. The analyte list was prioritized to include carcinogenic polyaromatic hydrocarbons (PAHs), the most commonly occurring polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs), persistent bioaccumulative and toxic chemicals (PBTs), and emergent contaminants of concern (ECCs) as indicators of human sewage exposure. White sturgeon (Acipenser transmontanus) were selected for this study to support a larger ecotoxicological study to monitor contaminants as an assessment of fish health. Organ tissues contained high lipid content with percentages of 15% and 34% for liver and gonad, respectively. Overall recoveries from fortified sturgeon tissues were high, 71-98% for PAHs, 60-107% for PBDEs and PCBs, 86-107% for PBT chemicals, and 88-107% for ECCs with the exception of octinoxate (28%) from liver tissues. Analyte recovery trends decreased as analyte lipophilicity and molecular weight increased. These recoveries demonstrate that extraction using QuEChERS can be used for screening of the most common bioaccumulating organic compounds in high lipid fish tissue using a single extraction and analysis.

  11. Columbia River White Sturgeon Genetics and Early Life History: Population Segregation and Juvenile Feeding Behavior, 1987 Final Report.

    SciTech Connect

    Brannon, Ernest L.

    1988-06-01

    The geographic area of the genetics study broadly covered the distribution range of sturgeon in the Columbia from below Bonneville Dam at Ilwaco at Lake Roosevelt, the Upper Snake River, and the Kootenai River. The two remote river sections provided data important for enhancement considerations. There was little electrophoretic variation seen among individuals from the Kootenai River. Upper Snake river sturgeon showed a higher percentage of polymorphic loci than the Kootenai fish, but lower than the other areas in the Columbia River we sampled. Sample size was increased in both Lake Roosevelt and at Electrophoretic variation was specific to an individual sampling area in several cases and this shaped our conclusions. The 1987 early life history studies concentrated on the feeding behavior of juvenile sturgeon. The chemostimulant components in prey attractive to sturgeon were examined, and the sensory systems utilized by foraging sturgeon were determined under different environmental conditions. These results were discussed with regard to the environmental changes that have occurred in the Columbia River. Under present river conditions, the feeding mechanism of sturgeon is more restricted to certain prey types, and their feeding range may be limited. In these situations, enhancement measures cannot be undertaken without consideration given to the introduction of food resources that will be readily available under present conditions. 89 refs., 7 figs., 11 tabs.

  12. Identification and expression of aryl hydrocarbon receptors (AhR1 and AhR2) provide insight in an evolutionary context regarding sensitivity of white sturgeon (Acipenser transmontanus) to dioxin-like compounds.

    PubMed

    Doering, Jon A; Wiseman, Steve; Beitel, Shawn C; Giesy, John P; Hecker, Markus

    2014-05-01

    Sturgeons are ancient fishes, which are endangered in many parts of the world. Due to their benthic nature and longevity, sturgeon are at great risk of exposure to bioaccumulative contaminants such as dioxin-like compounds (DLCs). Despite their endangered status, little research has been conducted to characterize the relative sensitivity of sturgeons to DLCs. Proper assessment of risk of DLCs posed to these fishes therefore, requires a better understanding of this sensitivity and the factors that are driving it. Adverse effects associated with exposure to DLCs are mediated by the aryl hydrocarbon receptor (AhR). This study identified and characterized two distinct AhRs, AhR1 and AhR2, in white sturgeon (Acipenser transmontanus) for the first time as a first step in studying the relative sensitivities of sturgeons to DLCs. Furthermore, tissue-specific expression of both AhRs under basal conditions and in response to exposure to the model DLC, β-naphthoflavone (βNF), was determined. The sequence of amino acids of AhR1 of white sturgeon had greater similarity to AhRs of tetrapods, including amphibians, birds, and mammals, than to AhR1s of other fishes. The sequence of amino acids in the ligand binding domain of the AhR1 had greater than 80% similarity to AhRs known to bind DLCs and was less similar to AhRs not known to bind DLCs. AhR2 of white sturgeon had greatest similarity to AhR2 of other fishes. Profiles of expression of AhR1 and AhR2 in white sturgeon were distinct from those known in other fishes and appear more similar to profiles observed in birds. Expressions of both AhR1 and AhR2 of white sturgeon were greatest in liver and heart, which are target organs for DLCs. Furthermore, abundances of transcripts of AhR1 and AhR2 in all tissues from white sturgeon were greater than controls (up to 35-fold) following exposure to βNF. Based upon both AhRs having similar abundances of transcript in target organs of DLC toxicity, both AhRs being up-regulated following

  13. Identification and expression of aryl hydrocarbon receptors (AhR1 and AhR2) provide insight in an evolutionary context regarding sensitivity of white sturgeon (Acipenser transmontanus) to dioxin-like compounds.

    PubMed

    Doering, Jon A; Wiseman, Steve; Beitel, Shawn C; Giesy, John P; Hecker, Markus

    2014-05-01

    Sturgeons are ancient fishes, which are endangered in many parts of the world. Due to their benthic nature and longevity, sturgeon are at great risk of exposure to bioaccumulative contaminants such as dioxin-like compounds (DLCs). Despite their endangered status, little research has been conducted to characterize the relative sensitivity of sturgeons to DLCs. Proper assessment of risk of DLCs posed to these fishes therefore, requires a better understanding of this sensitivity and the factors that are driving it. Adverse effects associated with exposure to DLCs are mediated by the aryl hydrocarbon receptor (AhR). This study identified and characterized two distinct AhRs, AhR1 and AhR2, in white sturgeon (Acipenser transmontanus) for the first time as a first step in studying the relative sensitivities of sturgeons to DLCs. Furthermore, tissue-specific expression of both AhRs under basal conditions and in response to exposure to the model DLC, β-naphthoflavone (βNF), was determined. The sequence of amino acids of AhR1 of white sturgeon had greater similarity to AhRs of tetrapods, including amphibians, birds, and mammals, than to AhR1s of other fishes. The sequence of amino acids in the ligand binding domain of the AhR1 had greater than 80% similarity to AhRs known to bind DLCs and was less similar to AhRs not known to bind DLCs. AhR2 of white sturgeon had greatest similarity to AhR2 of other fishes. Profiles of expression of AhR1 and AhR2 in white sturgeon were distinct from those known in other fishes and appear more similar to profiles observed in birds. Expressions of both AhR1 and AhR2 of white sturgeon were greatest in liver and heart, which are target organs for DLCs. Furthermore, abundances of transcripts of AhR1 and AhR2 in all tissues from white sturgeon were greater than controls (up to 35-fold) following exposure to βNF. Based upon both AhRs having similar abundances of transcript in target organs of DLC toxicity, both AhRs being up-regulated following

  14. Final Environmental Assessment and Finding of No Significant Impact: White Sturgeon Mitigation and Restoration in the Columbia and Snake Rivers Upstream from Bonneville Dam

    SciTech Connect

    N /A

    2003-04-23

    Bonneville Power Administration (BPA) is proposing to fund the White Sturgeon Mitigation and Restoration in the Columbia and Snake Rivers Upstream from Bonneville Dam Project. The project proposes to continue to carry out harvest monitoring and stock status updates coordinated with fisheries management planning, annual young-of-the year recruitment indexing, research, experimental artificial propagation, and transport of white sturgeon to less densely populated areas of the river(s). Additionally, release of hatchery-reared juveniles is proposed to evaluate release strategies. Actions will take place in the following Columbia River mainstem reaches: Bonneville, The Dalles, John Day, and McNary Reservoirs; Hanford Reach, as well as the Wanapum and Rock Island Reservoirs; and the following Snake River mainstem reaches: Ice Harbor, Lower Monumental and Little Goose Reservoirs. Spawning and rearing are undertaken at established hatcheries at McNary Dam and also the Abernathy Fish Technology Center. BPA has prepared an Environmental Assessment (EA) (DOE/EA-1367, April 2003) evaluating the proposed project. Based on the analysis in the EA, BPA has determined that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an Environmental Impact Statement (EIS) is not required, and BPA is issuing this Finding of No Significant Impact (FONSI).

  15. Characterization of the contents and histology of the gastrointestinal tracts of White Sturgeon (Acipenser transmontanus) captured from Upper Lake Roosevelt, Washington, October 2008

    USGS Publications Warehouse

    Parsley, Michael J.; van der Leeuw, Bjorn K.; Elliott, Diane G.

    2010-01-01

    The gastrointestinal tracts of 37 juvenile white sturgeon (Acipenser transmontanus) captured from the upper part of Lake Roosevelt during October 2008, were examined to identify prey taxa and to determine if the fish were consuming smelter slag along with other sediments. Histological examination of the gastrointestinal tract tissues and comparison with similar tissues from hatchery-reared fish also was performed. The contents of the gastro-intestinal tracts (guts) indicated that white sturgeon were actively foraging on various benthic invertebrates and the diet was quite diverse, with more than 50 percent of the fish feeding on five or more different taxa. Slag was present in 76 percent of the guts examined. Although not all guts contained slag particles, larger fish tended to have greater amounts of slag in their guts. Histology of the gut tissues showed the presence of a chronic inflammatory response, and the severity of the response had a significant positive correlation (P = 0.01) with fish length and weight suggesting that the inflammation represented a response to long-term exposure to one or more stressors. However, additional work is needed to determine if the physical or chemical properties of slag contributed to this response.

  16. Status and Habitat Requirements of White Sturgeon Populations in the Columbia River Downstream from McNary Dam, 1989-1990 Annual Report.

    SciTech Connect

    Nigro, Anthony A.

    1990-09-01

    We report on our progress from April 1989 through March 1990 on determining the status and habitat requirements of white sturgeon populations in the Columbia River downstream from McNary Dam. The study is a cooperative effort by the Oregon Department of Fish and Wildlife (ODFW), Washington Department of Fisheries (WDF), US Fish and Wildlife Service (FWS) and National Marine Fisheries Service (NMFS). Study objectives addressed by each agency are to describe the life history and population dynamics of subadults and adults between Bonneville and McNary dams and evaluate the need and identify potential methods for protecting, mitigating and enhancing populations downstream from McNary Dam, to describe the white sturgeon recreational fishery between Bonneville and McNary dams, describe reproductive and early life history characteristics downstream from Bonneville Dam and describe life history and population dynamics of subadults and adults downstream from Bonneville Dam, to describe reproduction and early life history characteristics, define habitat requirements for spawning and rearing and quantify extent of habitat available between Bonneville and McNary dams, and to describe reproduction and early life history characteristics, define habitat requirements for spawning and rearing and quantify extent of habitat available downstream from Bonneville Dam. Our approach is to work concurrently downstream and upstream from Bonneville Dam. Upstream from Bonneville Dam we began work in the Dalles Reservoir in 1987 and expanded efforts to Bonneville Reservoir in 1988 and John Day Reservoir in 1989. Highlights from this work is also included. 47 refs., 33 figs., 66 tabs.

  17. Simulation of flow and sediment mobility using a multidimensional flow model for the White Sturgeon critical-habitat reach, Kootenai River near Bonners Ferry, Idaho

    USGS Publications Warehouse

    Barton, Gary J.; McDonald, Richard R.; Nelson, Jonathan M.; Dinehart, Randal L.

    2005-01-01

    In 1994, the Kootenai River white sturgeon (Acipenser transmontanus) was listed as an Endangered Species as a direct result of two related observations. First, biologists observed that the white sturgeon population in the Kootenai River was declining. Second, they observed a decline in recruitment of juvenile sturgeon beginning in the 1950s with an almost total absence of recruitment since 1974, following the closure of Libby Dam in 1972. This second observation was attributed to changes in spawning and (or) rearing habitat resulting from alterations in the physical habitat, including flow regime, sediment-transport regime, and bed morphology of the river. The Kootenai River White Sturgeon Recovery Team was established to find and implement ways to improve spawning and rearing habitat used by white sturgeon. They identified the need to develop and apply a multidimensional flow model to certain reaches of the river to quantify physical habitat in a spatially distributed manner. The U.S. Geological Survey has addressed these needs by developing, calibrating, and validating a multidimensional flow model used to simulate streamflow and sediment mobility in the white sturgeon critical-habitat reach of the Kootenai River. This report describes the model and limitations, presents the results of a few simple simulations, and demonstrates how the model can be used to link physical characteristics of streamflow to biological or other habitat data. This study was conducted in cooperation with the Kootenai Tribe of Idaho along a 23-kilometer reach of the Kootenai River, including the white sturgeon spawning reach near Bonners Ferry, Idaho that is about 108 to 131 kilometers below Libby Dam. U.S. Geological Survey's MultiDimensional Surface-Water Modeling System was used to construct a flow model for the critical-habitat reach of the Kootenai River white sturgeon, between river kilometers 228.4 and 245.9. Given streamflow, bed roughness, and downstream water-surface elevation

  18. Breeding Plan to Preserve the Genetic Variability of the Kootenai River White Sturgeon, Final Report, December 1993.

    SciTech Connect

    Kincaid, Harold L.

    1993-11-01

    Natural reproduction in the Kootenai River white sturgeon population has not produced a successful year class since 1974, resulting in a declining broodstock and 20 consecutive year classes missing from the age-class structure. This report describes a captive breeding plan designed to preserve the remaining genetic variability and to begin rebuilding the natural age class structure. The captive breeding program will use 3--9 females and an equal number of males captured from the Kootenai River each spring. Fish will be spawned in pairs or in diallel mating designs to produce individual families that will be reared separately to maintain family identity. Fish will be marked to identify family and year class before return to the river. Fish should be returned to the river as fall fingerlings to minimize potential adaptation to the hatchery environment Initially, while tagging methods are tested to ensure positive identification after return to the river, it may be necessary to plant fish as spring yearlings. Number of fish planted will be equalized at 5,000 per family if fall fingerlings or 1,000 per family if spring yearlings. Assuming annual survival rates of 20% during the first winter for fall fingerling plants and 50% for years 1--3, and 85% for years 4--20 of all fish planted, the target numbers would yield 7.9 progeny per family or about 4 breeding pairs at age 20. Natural survival in the river environment during the 19+ years from planting to maturity would result in variability in genetic contribution of families to the next broodstock generation. Fish planted per family would be adjusted in future years when actual survival rate information is known. Broodfish will be tagged when captured to minimize multiple spawning of the same fish. implementation of this breeding plan each year for the 20-year generation interval, using 5 different mating pairs each year, will yield an effective population size of 200, or 22.5% of the estimated 1990 population.

  19. Distinguishing ovarian maturity of farmed white sturgeon (Acipenser transmontanus) by Fourier transform infrared spectroscopy: a potential tool for caviar production management.

    PubMed

    Lu, Xiaonan; Webb, Molly; Talbott, Mariah; Van Eenennaam, Joel; Palumbo, Amanda; Linares-Casenave, Javier; Doroshov, Serge; Struffenegger, Peter; Rasco, Barbara

    2010-04-14

    Fourier transform infrared spectroscopy (FT-IR, 4000-400 cm(-1)) was applied to blood plasma of farmed white sturgeon (N = 40) to differentiate and predict the stages of ovarian maturity. Spectral features of sex steroids (approximately 3000 cm(-1)) and vitellogenin (approximately 1080 cm(-1)) were identified. Clear segregation of maturity stages (previtellogenesis, vitellogenesis, postvitellogenesis, and follicular atresia) was achieved using principal component analysis (PCA). Progression of oocyte development in the late phase of vitellogenesis was also monitored using PCA based on changes in plasma concentrations of sex steroid and lipid content. The observed oocyte polarization index (PI, a measure of nuclear migration) was correlated with changes in plasma sex steroid levels revealed by FT-IR PCA results. A partial least squares (PLS) model predicted PI values within the range 0.12-0.40 (R = 0.95, SEP = 2.18%) from differences in spectral features. These results suggest that FT-IR may be a good tool for assessing ovarian maturity in farmed sturgeon and will reduce the need for the invasive ovarian biopsy required for PI determination.

  20. Effects of Mitigative Measures on Productivity of White Sturgeon Populations in the Columbia River Downstream from McNary Dam: Determine Status and Habitat Requirements of White Sturgeon Populations in the Columbia and Snake Rivers Upstream from McNary Dam, 1997-1998 Annual Report.

    SciTech Connect

    Ward, David L.

    1999-02-01

    The authors report on their progress from April 1997 through March 1998 on determining the effects of mitigative measures on productivity of white sturgeon populations in the Columbia River downstream from McNary Dam, and on determining the status and habitat requirements of white sturgeon populations in the Columbia and Snake rivers upstream from McNary Dam. The study is a cooperative effort by the Oregon Department of Fish and Wildlife (ODFW; Report A), Washington Department of Fish and Wildlife (WDFW; Report B), U.S. Geological Survey Biological Resources Division (USGS; Report C), National Marine Fisheries Service (NMFS; Report D), U.S. Fish and Wildlife Service (USFWS; Report E), and Columbia River Inter-Tribal Fish Commission (CRITFC; Report F). This is a multi-year study with many objectives requiring more than one year to complete. Therefore, findings from a given year may be part of more significant findings yet to be reported. Highlights of results of the work from April 1997 through March 1998 listed.

  1. Evidence of Detrimental Effects of Environmental Contaminants on Growth and Reproductive Physiology of White Sturgeon in Impounded Areas of the Columbia River

    PubMed Central

    Feist, Grant W.; Webb, Molly A.H.; Gundersen, Deke T.; Foster, Eugene P.; Schreck, Carl B.; Maule, Alec G.; Fitzpatrick, Martin S.

    2005-01-01

    This study sought to determine whether wild white sturgeon from the Columbia River (Oregon) were exhibiting signs of reproductive endocrine disruption. Fish were sampled in the free-flowing portion of the river (where the population is experiencing reproductive success) and from three reservoirs behind hydroelectric dams (where fish have reduced reproductive success). All of the 18 pesticides and almost all of the 28 polychlorinated biphenyls (PCBs) that were analyzed in livers and gonads were detected in at least some of the tissue samples. Metabolites of p,p′-dichlorodiphenyltrichloroethane (DDT) [p,p′-dichlorodiphenyldichloroethylene (DDE) and p,p′-1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (DDD)] were consistently found at relatively high levels in fish. Some males and immature females showed elevated plasma vitellogenin; however, concentrations were not correlated with any of the pesticides or PCBs analyzed. Negative correlations were found between a number of physiologic parameters and tissue burdens of toxicants. Plasma triglycerides and condition factor were negatively correlated with total DDT (DDD + DDE + DDT), total pesticides (all pesticides detected – total DDT), and PCBs. In males, plasma androgens and gonad size were negatively correlated with total DDT, total pesticides, and PCBs. Fish residing in the reservoir behind the oldest dam had the highest contaminant loads and incidence of gonadal abnormalities, and the lowest triglycerides, condition factor, gonad size, and plasma androgens. These data suggest that endocrine-disrupting chemicals may be accumulating behind dams over time. Overall, results of this study indicate that exposure to environmental contaminants may be affecting both growth and reproductive physiology of sturgeon in some areas of the Columbia River. PMID:16330346

  2. Evidence of detrimental effects of environmental contaminants on growth and reproductive physiology of white sturgeon in impounded areas of the Columbia River

    USGS Publications Warehouse

    Feist, G.W.; Webb, M.A.H.; Gundersen, D.T.; Foster, E.P.; Schreck, C.B.; Maule, A.G.; Fitzpatrick, M.S.

    2005-01-01

    This study sought to determine whether wild white sturgeon from the Columbia River (Oregon) were exhibiting signs of reproductive endocrine disruption. Fish were sampled in the free-flowing portion of the river (where the population is experiencing reproductive success) and from three reservoirs behind hydroelectric dams (where fish have reduced reproductive success). All of the 18 pesticides and almost all of the 28 polychlorinated biphenyls (PCBs) that were analyzed in livers and gonads were detected in at least some of the tissue samples. Metabolites of p,p???-dichlorodiphenyltrichloroethane (DDT) [p,p???-dichlorodiphenyldichloroethylene (DDE) and p,p???-1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (DDD)] were consistently found at relatively high levels in fish. Some males and immature females showed elevated plasma vitellogenin; however, concentrations were not correlated with any of the pesticides or PCBs analyzed. Negative correlations were found between a number of physiologic parameters and tissue burdens of toxicants. Plasma triglycerides and condition factor were negatively correlated with total DDT (DDD + DDE + DDT), total pesticides (all pesticides detected - total DDT), and PCBs. In males, plasma androgens and gonad size were negatively correlated with total DDT, total pesticides, and PCBs. Fish residing in the reservoir behind the oldest dam had the highest contaminant loads and incidence of gonadal abnormalities, and the lowest triglycerides, condition factor, gonad size, and plasma androgens. These data suggest that endocrine-disrupting chemicals may be accumulating behind dams over time. Overall, results of this study indicate that exposure to environmental contaminants may be affecting both growth and reproductive physiology of sturgeon in some areas of the Columbia River.

  3. Do Sturgeon limit burrowing shrimp populations in Pacific Northwest estuaries?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Green sturgeon (Acipenser medirostris) and white sturgeon (Acipenser transmontanus) are common seasonal inhabitants of coastal estuaries from California USA to British Columbia, Canada. Both species are anadromous spending significant portions of their lives at sea and in their natal streams, but t...

  4. Gulf Sturgeon Facts

    USGS Publications Warehouse

    Sulak, Kenneth J.; Randall, Michael

    2008-01-01

    Sturgeon: An ancient type of fish, with 5 rows of armor scutes, a cartilaginous skeleton, long snout, suction mouth, no teeth, and 4 barbels. Photograph of a Gulf sturgeon. The total length of a 5-month old is 313 mm.

  5. Sturgeon study - specimens needed

    SciTech Connect

    Snyder, D.E.; Matthews, R.A.

    1983-01-01

    Preliminary results of a study to determine morphological criteria and verify those already suggested in the published literature for identifying the larvae of the Atlantic sturgeon and the endangered short nose sturgeon are presented. (ACR)

  6. 33 CFR 110.78 - Sturgeon Bay, Sturgeon Bay, Wis.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Sturgeon Bay, Sturgeon Bay, Wis... ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.78 Sturgeon Bay, Sturgeon Bay, Wis. (a) Area 1. Beginning at a point bearing 126°, 3,000 feet from the fixed green Sturgeon Bay Canal Leading Light...

  7. 33 CFR 110.78 - Sturgeon Bay, Sturgeon Bay, Wis.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Sturgeon Bay, Sturgeon Bay, Wis... ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.78 Sturgeon Bay, Sturgeon Bay, Wis. (a) Area 1. Beginning at a point bearing 126°, 3,000 feet from the fixed green Sturgeon Bay Canal Leading Light...

  8. 33 CFR 110.78 - Sturgeon Bay, Sturgeon Bay, Wis.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Sturgeon Bay, Sturgeon Bay, Wis... ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.78 Sturgeon Bay, Sturgeon Bay, Wis. (a) Area 1. Beginning at a point bearing 126°, 3,000 feet from the fixed green Sturgeon Bay Canal Leading Light...

  9. 33 CFR 110.78 - Sturgeon Bay, Sturgeon Bay, Wis.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Sturgeon Bay, Sturgeon Bay, Wis... ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.78 Sturgeon Bay, Sturgeon Bay, Wis. (a) Area 1. Beginning at a point bearing 126°, 3,000 feet from the fixed green Sturgeon Bay Canal Leading Light...

  10. 33 CFR 110.78 - Sturgeon Bay, Sturgeon Bay, Wis.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Sturgeon Bay, Sturgeon Bay, Wis... ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.78 Sturgeon Bay, Sturgeon Bay, Wis. (a) Area 1. Beginning at a point bearing 126°, 3,000 feet from the fixed green Sturgeon Bay Canal Leading Light...

  11. Sperm-cell ultrastructure of North American sturgeons. IV. The pallid sturgeon (Scaphirhynchus albus Forbes and Richardson, 1905)

    USGS Publications Warehouse

    DiLauro, M.N.; Walsh, R.A.; Peiffer, M.; Bennett, R.M.

    2001-01-01

    Sperm-cell morphology and ultrastructure in the pallid sturgeon (Scaphirhynchus albus) were examined using transmission and scanning electron microscopy. Metrics and structure were compared with similar metrics obtained from other published descriptions of sturgeon sperm cells. General morphology was found to be similar to that of sperm cells of the white (Acipenser transmontanus), lake (A. fulvescens), stellate (A. stellatus), Chinese (A. sinensis), Russian (A. gueldenstaedti colchicus), and shortnose (A. brevirostrum) sturgeons, which all shared a gradual tapering of the nuclear diameter from posterior to anterior, unlike that of the Atlantic sturgeon (A. oxyrhynchus). The sperm cell of the pallid sturgeon was similar in size to that of the Atlantic sturgeon, being only slightly larger. The sperm cell of the pallid sturgeon differed from those of other sturgeons chiefly in the acrosomal region, where the posterolateral projections (PLP) have the shape of an acute triangle and are arranged in a spiral about the longitudinal axis of the cell. The PLP were longer than those of other sturgeons, being twice the length of those of the Atlantic sturgeon and 58% longer than those of the lake sturgeon. Also, in cross section the acrosome had the shape of a hollow cone rather than the cap of an oak tree acorn, as was found in ultrastructural studies of other sturgeons. In addition, we were able to confirm that the structural arrangement of the distal centriole of the midpiece is identical with that of the proximal centriole: nine sets of microtubular triplets around the periphery of the centriole. This information is of potential use to fishery biologists, forensic biologists, zoologists, reproductive physiologists, taxonomists, evolutionary biologists, and aquaculturists.

  12. Characterization of channel substrate, and changes in suspended-sediment transport and channel geometry in white sturgeon spawning habitat in the Kootenai River near Bonners Ferry, Idaho, following the closure of Libby Dam

    USGS Publications Warehouse

    Barton, Gary J.

    2004-01-01

    Many local, State, and Federal agencies have concerns over the declining population of white sturgeon (Acipenser transmontanus) in the Kootenai River and the possible effects of the closure and subsequent operation of Libby Dam in 1972. In 1994, the Kootenai River white sturgeon was listed as an Endangered Species. A year-long field study was conducted in cooperation with the Kootenai Tribe of Idaho along a 21.7-kilometer reach of the Kootenai River including the white sturgeon spawning reach near Bonners Ferry, Idaho, approximately 111 to 129 kilometers below Libby Dam. During the field study, data were collected in order to map the channel substrate in the white sturgeon spawning reach. These data include seismic subbottom profiles at 18 cross sections of the river and sediment cores taken at or near the seismic cross sections. The effect that Libby Dam has on the Kootenai River white sturgeon spawning substrate was analyzed in terms of changes in suspended-sediment transport, aggradation and degradation of channel bed, and changes in the particle size of bed material with depth below the riverbed. The annual suspended-sediment load leaving the Kootenai River white sturgeon spawning reach decreased dramatically after the closure of Libby Dam in 1972: mean annual pre-Libby Dam load during 1966–71 was 1,743,900 metric tons, and the dam-era load during 1973–83 was 287,500 metric tons. The amount of sand-size particles in three suspended-sediment samples collected at Copeland, Idaho, 159 kilometers below Libby Dam, during spring and early summer high flows after the closure of Libby Dam is less than in four samples collected during the pre-Libby Dam era. The supply of sand to the spawning reach is currently less due to the reduction of high flows and a loss of 70 percent of the basin after the closure of Libby Dam. The river's reduced capacity to transport sand out of the spawning reach is compensated to an unknown extent by a reduced load of sand entering the

  13. Characterization of channel substrate, and changes in suspended-sediment transport and channel geometry in white sturgeon spawning habitat in the Kootenai River near Bonners Ferry, Idaho, following the closure of Libby Dam

    USGS Publications Warehouse

    Barton, Gary J.

    2004-01-01

    Many local, State, and Federal agencies have concerns over the declining population of white sturgeon (Acipenser transmontanus) in the Kootenai River and the possible effects of the closure and subsequent operation of Libby Dam in 1972. In 1994, the Kootenai River white sturgeon was listed as an Endangered Species. A year-long field study was conducted in cooperation with the Kootenai Tribe of Idaho along a 21.7-kilometer reach of the Kootenai River including the white sturgeon spawning reach near Bonners Ferry, Idaho, approximately 111 to 129 kilometers below Libby Dam. During the field study, data were collected in order to map the channel substrate in the white sturgeon spawning reach. These data include seismic subbottom profiles at 18 cross sections of the river and sediment cores taken at or near the seismic cross sections. The effect that Libby Dam has on the Kootenai River white sturgeon spawning substrate was analyzed in terms of changes in suspended-sediment transport, aggradation and degradation of channel bed, and changes in the particle size of bed material with depth below the riverbed. The annual suspended-sediment load leaving the Kootenai River white sturgeon spawning reach decreased dramatically after the closure of Libby Dam in 1972: mean annual pre-Libby Dam load during 1966–71 was 1,743,900 metric tons, and the dam-era load during 1973–83 was 287,500 metric tons. The amount of sand-size particles in three suspended-sediment samples collected at Copeland, Idaho, 159 kilometers below Libby Dam, during spring and early summer high flows after the closure of Libby Dam is less than in four samples collected during the pre-Libby Dam era. The supply of sand to the spawning reach is currently less due to the reduction of high flows and a loss of 70 percent of the basin after the closure of Libby Dam. The river's reduced capacity to transport sand out of the spawning reach is compensated to an unknown extent by a reduced load of sand entering the

  14. Integrating Water Flow, Locomotor Performance and Respiration of Chinese Sturgeon during Multiple Fatigue-Recovery Cycles

    PubMed Central

    Cai, Lu; Chen, Lei; Johnson, David; Gao, Yong; Mandal, Prashant; Fang, Min; Tu, Zhiying; Huang, Yingping

    2014-01-01

    The objective of this study is to provide information on metabolic changes occurring in Chinese sturgeon (an ecologically important endangered fish) subjected to repeated cycles of fatigue and recovery and the effect on swimming capability. Fatigue-recovery cycles likely occur when fish are moving through the fishways of large dams and the results of this investigation are important for fishway design and conservation of wild Chinese sturgeon populations. A series of four stepped velocity tests were carried out successively in a Steffensen-type swimming respirometer and the effects of repeated fatigue-recovery on swimming capability and metabolism were measured. Significant results include: (1) critical swimming speed decreased from 4.34 bl/s to 2.98 bl/s; (2) active oxygen consumption (i.e. the difference between total oxygen consumption and routine oxygen consumption) decreased from 1175 mgO2/kg to 341 mgO2/kg and was the primary reason for the decrease in Ucrit; (3) excess post-exercise oxygen consumption decreased from 36 mgO2/kg to 22 mgO2/kg; (4) with repeated step tests, white muscle (anaerobic metabolism) began contributing to propulsion at lower swimming speeds. Therefore, Chinese sturgeon conserve energy by swimming efficiently and have high fatigue recovery capability. These results contribute to our understanding of the physiology of the Chinese sturgeon and support the conservation efforts of wild populations of this important species. PMID:24714585

  15. Defining winter trophic habitat of juvenile Gulf Sturgeon in the Suwannee and Apalachicola rivermouth estuaries, acoustic telemetry investigations

    USGS Publications Warehouse

    Sulak, K.J.; Randall, M.T.; Edwards, R.E.; Summers, T.M.; Luke, K.E.; Smith, W.T.; Norem, A.D.; Harden, William M.; Lukens, R.H.; Parauka, F.; Bolden, S.; Lehnert, R.

    2009-01-01

    Three automated listening post-telemetry studies were undertaken in the Suwannee and Apalachicola estuaries to gain knowledge of habitats use by juvenile Gulf Sturgeons (Acipenser oxyrinchus desotoi) on winter feeding grounds. A simple and reliable method for external attachment of small acoustic tags to the dorsal fin base was developed using shrink-tubing. Suspending receivers on masts below anchored buoys improved reception and facilitated downloading; a detection range of 500–2500 m was realized. In the Apalachicola estuary, juvenile GS stayed in shallow water (< 2 m) within the estuarine transition zone all winter in the vicinity of the Apalachicola River mouth. Juvenile GS high-use areas did not coincide with high density benthic macrofauna areas from the most recent (1999) benthos survey. In the Suwannee estuary, juveniles ranged widely and individually throughout oligohaline to mesohaline subareas of the estuary, preferentially using mesohaline subareas seaward of Suwannee Reef (52% of acoustic detections). The river mouth subarea was important only in early and late winter, during the times of adult Gulf Sturgeon migrations (41% of detections). Preferred winter feeding subareas coincided spatially with known areas of dense macrofaunal benthos concentrations. Following a dramatic drop in air and water temperatures, juvenile GS left the river mouth and estuary, subsequently being detected 8 km offshore in polyhaline open Gulf of Mexico waters, before returning to the estuary. Cold-event offshore excursions demonstrate that they can tolerate full-salinity polyhaline waters in the open Gulf of Mexico, for at least several days at a time. For juvenile sturgeons, the stress and metabolic cost of enduring high salinity (Jarvis et al., 2001; McKenzie et al., 2001; Singer and Ballantyne, 2002) for short periods in deep offshore waters seems adaptively advantageous relative to the risk of cold-event mortality in shallow inshore waters of lower salinity. Thus

  16. Evaluate Potential Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 1998 Annual Report.

    SciTech Connect

    Everett, Scott R.; Tuell, Michael A.

    2002-03-01

    In 1998 white sturgeon (Acipenser transmontanus) were captured, marked, and population data were collected in the Snake River between Lower Granite Dam and the mouth of the Salmon River. A total of 13,785 hours of setline effort and 389 hours of hook-and-line effort was employed in 1998. Of the 278 white sturgeon captured in the Snake River, 238 were marked for future identification. Three sturgeon were captured in the Salmon River and none were captured in the Clearwater River. Since 1997, 6.9% of the tagged fish have been recovered. Movement of recaptured white sturgeon ranged from 98.5 kilometers downstream to 60.7 kilometers upstream, however, less than 25% of the fish moved more than 16 kilometers (10 miles). In the Snake River, white sturgeon ranged in total length from 51.5 cm to 286 cm and averaged 118.9 cm. Differences were detected in the length frequency distributions of sturgeon in Lower Granite Reservoir and the free-flowing Snake River (Chi-Square test, P < 0.05). In addition, the proportion of white sturgeon greater than 92 cm (total length) in the free-flowing Snake River has shown an increase of 37% since the 1970's. Analysis of the length-weight relationship indicated that white sturgeon in Lower Granite Reservoir were slightly larger than white sturgeon in the free-flowing Snake River.

  17. Outbreak of mortality in Russian (Acipenser gueldenstaedtii) and Siberian (Acipenser baerii) sturgeons associated with sturgeon nucleo-cytoplasmatic large DNA virus.

    PubMed

    Ciulli, S; Volpe, E; Sirri, R; Passalacqua, P L; Cesa Bianchi, F; Serratore, P; Mandrioli, L

    2016-08-15

    Diseased outbreaks with high mortality in farmed sturgeon are a limiting factor to the success of this emerging aquaculture sector in Europe. Thorough investigations of outbreaks can determine the aetiological agents, identify important pathological and epidemiological pathways of infections and pave the way for effective control strategies. A thorough investigation of a mortality outbreak in Russian (Acipenser gueldenstaedtii) and Siberian (Acipenser baerii) sturgeons in Italy, demonstrated the primary involvement of a sturgeon nucleo-cytoplasmic large DNA virus (NCLDV). While, the taxonomy classification of this new virus is still uncertain, its involvement in sturgeon mortality outbreaks in Europe is, for the first time, fully investigated and described. Furthermore, the coinfection of bacteria such as motile Aeromonas spp. and Acinetobacter spp. was reported. Genetic characterisation showed the close relationship between the European sturgeon NCLDV with North American sturgeon NCLDVs. Similarly to the latter, the European sturgeon NCLDV persists in survivors. Furthermore, a systemic distribution of the European sturgeon NCLDV was evident in diseased A. baerii and A. gueldenstaedtii and in recovered A. gueldenstaedtii. These epidemiological and pathological findings will help in the identification of effective control strategies for sturgeon NCLDV infection, which afflicts an important and emerging European aquaculture sector.

  18. TOXIC EFFECTS OF PCB126 AND TCDD ON SHORTNOSE STURGEON AND ATLANTIC STURGEON

    PubMed Central

    Chambers, R. Christopher; Davis, Dawn D.; Habeck, Ehren A.; Roy, Nirmal K.

    2014-01-01

    Exposure to chemical contaminants is often invoked to explain recruitment failures to populations of sturgeon worldwide, but there is little empirical evidence to support the idea that young sturgeon are sensitive at environmentally relevant concentrations. The authors used shortnose sturgeon (Acipenser brevirostum) and Atlantic sturgeon (Acipenser oxyrinchus) as models to investigate the sensitivities of sturgeon to early-life-stage toxicities from embryonic exposures to graded doses of polychlorinated biphenyl 126 (PCB126) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Survival to hatching of shortnose sturgeon decreased with increasing dose, although the duration of the embryonic period was not significantly altered by exposure in either species. Morphometric features of larvae of both species were affected by dose, including shortening of the body, reduction in head size, reduction in quantity of yolk reserves, and reduction in eye size. Eye development in both species was delayed with increasing dose for both chemicals. The persistence of larvae in a food-free environment decreased inversely with dose in both species, with sharp declines occurring at PCB126 and TCDD doses of ≥1 ppb and ≥0.1 ppb, respectively. Dose-responsive early-life-stage toxicities reported here are among the more sensitive found in fish and occurred at burdens similar to those found in situ in a sympatric bottom-dwelling bony fish in the Hudson River Estuary. The present study is among the first demonstrating the sensitivity of any sturgeon to the hallmark early-life-stage toxicities induced by aryl hydrocarbon receptor agonists. PMID:22825886

  19. Investigating white-nose syndrome in bats

    USGS Publications Warehouse

    Blehert, David S.

    2009-01-01

    A devastating, emergent disease afflicting hibernating bats has pread from the northeast to the mid-Atlantic region of the United States at an alarming rate. Since the winter of 2006-2007, hundreds of thousands of insect-eating bats from at least nine states have died from this new disease, named White-Nose Syndrome (WNS). The disease is named for the white fungus often seen on the muzzles, ears, and wings of bats. This disease poses a threat to cave hibernating bats of the United States and potentially all temperate regions of the world. USGS scientists from the National Wildlife Health Center (NWHC) and the Fort Collins Science Center (FORT), in collaboration with the New York State Department of Environmental Conservation, the U.S. Fish and Wildlife Service, and others have linked a newly described, cold-loving fungus to WNS.

  20. White University Students' Responses to Societal Racism: A Qualitative Investigation

    ERIC Educational Resources Information Center

    Spanierman, Lisa A.; Oh, Euna; Poteat, V. Paul; Hund, Anita R.; McClair, Vetisha L.; Beer, Amanda M.; Clarke, Alexis M.

    2008-01-01

    The purpose of this investigation was to extend earlier conceptual and empirical literature on the ways in which White individuals respond to societal racism. To this end, the authors conducted in-depth interviews to examine 11 midwestern, non-Hispanic, White university students' reactions and experiences related to individual and institutional…

  1. 33 CFR 162.125 - Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...: The Corps of Engineers also has regulations dealing with these areas in 33 CFR Part 207. ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Sturgeon Bay and the Sturgeon Bay... Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc. (a) In the Sturgeon Bay Ship Canal: (1) No vessel...

  2. 33 CFR 162.125 - Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...: The Corps of Engineers also has regulations dealing with these areas in 33 CFR Part 207. ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Sturgeon Bay and the Sturgeon Bay... Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc. (a) In the Sturgeon Bay Ship Canal: (1) No vessel...

  3. 33 CFR 162.125 - Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...: The Corps of Engineers also has regulations dealing with these areas in 33 CFR Part 207. ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Sturgeon Bay and the Sturgeon Bay... Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc. (a) In the Sturgeon Bay Ship Canal: (1) No vessel...

  4. 33 CFR 162.125 - Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...: The Corps of Engineers also has regulations dealing with these areas in 33 CFR Part 207. ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Sturgeon Bay and the Sturgeon Bay... Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc. (a) In the Sturgeon Bay Ship Canal: (1) No vessel...

  5. Evaluate Potential Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 2001 Annual Report.

    SciTech Connect

    Everett, Scott R.; Tuell, Michael A.

    2003-03-01

    The specific research goal of this project is to identify means to restore and rebuild the Snake River white sturgeon (Acipenser transmontanus) population to support a sustainable annual subsistence harvest equivalent to 5 kg/ha/yr (CBFWA 1997). Based on data collected, a white sturgeon adaptive management plan will be developed. This 2001 annual report covers the fifth year of sampling of this multi-year study. In 2001 white sturgeon were captured, marked, and population data were collected in the Snake and Salmon rivers. The Snake River was sampled between Lower Granite Dam (rkm 174) and the mouth of the Salmon River (rkm 303), and the Salmon River was sampled from its mouth upstream to Hammer Creek (rkm 84). A total of 45,907 hours of setline effort and 186 hours of hook-and-line effort was employed in 2001. A total of 390 white sturgeon were captured and tagged in the Snake River and 12 in the Salmon River. Since 1997, 36.1 percent of the tagged white sturgeon have been recaptured. In the Snake River, white sturgeon ranged in total length from 42 cm to 307 cm and averaged 107 cm. In the Salmon River, white sturgeon ranged in total length from 66 cm to 235 cm and averaged 160 cm. Using the Jolly-Seber model, the abundance of white sturgeon <60 cm, between Lower Granite Dam and the mouth of the Salmon River, was estimated at 2,483 fish, with a 95% confidence interval of 1,208-7,477. An additional 10 white sturgeon were fitted with radio-tags during 2001. The locations of 17 radio-tagged white sturgeon were monitored in 2001. The movement of these fish ranged from 38.6 km (24 miles) downstream to 54.7 km (34 miles) upstream; however, 62.6 percent of the detected movement was less than 0.8 km (0.5 mile). Both radio-tagged fish and recaptured white sturgeon in Lower Granite Reservoir appear to move more than fish in the free-flowing segment of the Snake River. No seasonal movement pattern was detected, and no movement pattern was detected for different size fish

  6. Evaluate Potential Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 1999 Annual Report.

    SciTech Connect

    Tuell, Michael A.; Everett, Scott R.

    2003-03-01

    The specific research goal of this project is to identify means to restore and rebuild the Snake River white sturgeon (Acipenser transmontanus) population to support a sustainable annual subsistence harvest equivalent to 5 kg/ha/yr (CBFWA 1997). Based on data collected, a white sturgeon adaptive management plan will be developed. This 1999 annual report covers the third year of sampling of this multi-year study. In 1999 white sturgeon were captured, marked and population data were collected in the Snake and Salmon rivers. A total of 33,943 hours of setline effort and 2,112 hours of hook-and-line effort was employed in 1999. A total of 289 white sturgeon were captured and tagged in the Snake River and 29 in the Salmon River. Since 1997, 11.1 percent of the tagged white sturgeon have been recaptured. In the Snake River, white sturgeon ranged in total length from 27 cm to 261 cm and averaged 110 cm. In the Salmon River, white sturgeon ranged in total length from 98 cm to 244 cm and averaged 183.5 cm. Using the Jolly-Seber model, the abundance of white sturgeon < 60 cm, between Lower Granite Dam and the mouth of the Salmon River, was estimated at 1,823 fish, with a 95% confidence interval of 1,052-4,221. A total of 15 white sturgeon were fitted with radio-tags. The movement of these fish ranged from 6.4 km (4 miles) downstream to 13.7 km (8.5 miles) upstream; however, 83.6 percent of the detected movement was less than 0.8 kilometers (0.5 miles). Both radio-tagged fish and recaptured white sturgeon in Lower Granite Reservoir appear to move more than fish in the free-flowing segment of the Snake River. No seasonal movement pattern was detected, and no movement pattern was detected for different size fish. Differences were detected in the length frequency distributions of white sturgeon in Lower Granite Reservoir and the free-flowing Snake River (Chi-Square test, P < 0.05). The proportion of white sturgeon greater than 92 cm (total length) in the free-flowing Snake River

  7. Evaluate Potential Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 2000 Annual Report.

    SciTech Connect

    Everett, Scott R.; Tuell, Michael A.

    2003-03-01

    The specific research goal of this project is to identify means to restore and rebuild the Snake River white sturgeon (Acipenser transmontanus) population to support a sustainable annual subsistence harvest equivalent to 5 kg/ha/yr (CBFWA 1997). Based on data collected, a white sturgeon adaptive management plan will be developed. This 2000 annual report covers the fourth year of sampling of this multi-year study. In 2000 white sturgeon were captured, marked, and population data were collected in the Snake and Salmon rivers. The Snake River was sampled between Lower Granite Dam (rkm 174) and the mouth of the Salmon River (rkm 303), and the Salmon River was sampled from its mouth upstream to Hammer Creek (rkm 84). A total of 53,277 hours of setline effort and 630 hours of hook-and-line effort was employed in 2000. A total of 538 white sturgeon were captured and tagged in the Snake River and 25 in the Salmon River. Since 1997, 32.8 percent of the tagged white sturgeon have been recaptured. In the Snake River, white sturgeon ranged in total length from 48 cm to 271 cm and averaged 107 cm. In the Salmon River, white sturgeon ranged in total length from 103 cm to 227 cm and averaged 163 cm. Using the Jolly-Seber open population estimator, the abundance of white sturgeon <60 cm, between Lower Granite Dam and the mouth of the Salmon River, was estimated at 2,725 fish, with a 95% confidence interval of 1,668-5,783. A total of 10 white sturgeon were fitted with radio-tags. The movement of these fish ranged from 54.7 km (34 miles) downstream to 78.8 km (49 miles) upstream; however, 43.6 percent of the detected movement was less than 0.8 km (0.5 mile). Both radio-tagged fish and recaptured white sturgeon in Lower Granite Reservoir appear to move more than fish in the free-flowing segment of the Snake River. No seasonal movement pattern was detected, and no movement pattern was detected for different size fish. Differences were detected in the length frequency distributions of

  8. Evaluate Potential Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 1997 Annual Report.

    SciTech Connect

    Hoefs, Nancy

    2004-02-01

    During 1997 the first phase of the Nez Perce Tribe White Sturgeon Project was completed and the second phase was initiated. During Phase I the ''Upper Snake River White Sturgeon Biological Assessment'' was completed, successfully: (1) compiling regional white sturgeon management objectives, and (2) identifying potential mitigation actions needed to rebuild the white sturgeon population in the Snake River between Hells Canyon and Lower Granite dams. Risks and uncertainties associated with implementation of these potential mitigative actions could not be fully assessed because critical information concerning the status of the population and their habitat requirements were unknown. The biological risk assessment identified the fundamental information concerning the white sturgeon population that is needed to fully evaluate the effectiveness of alternative mitigative strategies. Accordingly, a multi-year research plan was developed to collect specific biological and environmental data needed to assess the health and status of the population and characterize habitat used for spawning and rearing. In addition, in 1997 Phase II of the project was initiated. White sturgeon were captured, marked, and population data were collected between Lower Granite Dam and the mouth of the Salmon River. During 1997, 316 white sturgeon were captured in the Snake River. Of these, 298 were marked. Differences in the fork length frequency distributions of the white sturgeon were not affected by collection method. No significant differences in length frequency distributions of sturgeon captured in Lower Granite Reservoir and the mid- and upper free-flowing reaches of the Snake River were detected. The length frequency distribution indicated that white sturgeon between 92 and 183 cm are prevalent in the reaches of the Snake River that were sampled. However, white sturgeon >183 have not changed markedly since 1970. I would speculate that some factor other than past over-fishing practices is

  9. Seasonal distribution of Gulf of Mexico sturgeon in the pensacola bay system, Florida

    USGS Publications Warehouse

    Duncan, M.S.; Wrege, B.M.; Parauka, F.M.; Isely, J.J.

    2011-01-01

    Temporal and spatial distributions of Gulf of Mexico (Gulf) sturgeon Acipenser oxyrinchus desotoi were assessed in the Pensacola bay system, Florida, using stationary ultrasonic telemetry. Fifty-eight Gulf sturgeon were tagged within the Escambia (n=26), Yellow (n=8), Blackwater (n=12) and Choctawhatchee Rivers (n=12) in June, July, September and October, 2005. Fifty-four Gulf sturgeon were detected at least once during the study. Migration of sturgeon occurred throughout the bay system in fall, to various winter habitats in the Gulf of Mexico and Santa Rosa Sound. In spring, tagged sturgeon migrated back through the bay system to summer habitats in rivers. Based on the duration and number of detections, Gulf sturgeon primarily used the upper portions of East and Escambia Bays as migration routes in and out of all rivers during spring and summer and inhabited the lower portion of Pensacola Bay for longer durations in fall and winter. Specific areas within the Pensacola bay system were used in summer and winter that were not previously documented as essential sturgeon habitat. Areas in southeastern Pensacola Bay were heavily used during winter by a large portion of the population. Gulf sturgeon also exhibited long-term winter residency in Santa Rosa Sound for two consecutive years. An area in northeastern Escambia Bay supported Gulf sturgeon during the summer, which was unexpected and can not be explained by the data from this study. However, the discovery that Gulf sturgeon remain in the bay during the summer has important ecological and management implications that need further investigation. ?? 2011 Blackwell Verlag, Berlin.

  10. 33 CFR 117.1101 - Sturgeon Bay.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Michigan Street Bridge, mile 4.3 at Sturgeon Bay, shall open as follows: (1) From March 15 through December... draw of the Bayview (SR 42/57) Bridge, mile 3.0 at Sturgeon Bay, shall open as follows: (1) From March... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Sturgeon Bay. 117.1101...

  11. 33 CFR 117.1101 - Sturgeon Bay.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Michigan Street Bridge, mile 4.3 at Sturgeon Bay, shall open as follows: (1) From March 15 through December... draw of the Bayview (SR 42/57) Bridge, mile 3.0 at Sturgeon Bay, shall open as follows: (1) From March... passage. (c) The draw of the Maple-Oregon Bridge at Mile 4.17 at Sturgeon Bay, shall operate as...

  12. 50 CFR 223.211 - Atlantic sturgeon.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 10 2014-10-01 2014-10-01 false Atlantic sturgeon. 223.211 Section 223... Applicable to Threatened Marine and Anadromous Species § 223.211 Atlantic sturgeon. (a) Prohibitions. The... sturgeon listed in § 223.102(c)(29). (b)...

  13. 33 CFR 117.1101 - Sturgeon Bay.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Sturgeon Bay. 117.1101 Section... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Wisconsin § 117.1101 Sturgeon Bay. (a) The draw of the Michigan Street Bridge, mile 4.3 at Sturgeon Bay, shall open as follows: (1) From March 15 through...

  14. Experimental Investigation of White Layer formation in Hard Turning

    NASA Astrophysics Data System (ADS)

    Umbrello, D.; Rotella, G.; Crea, F.

    2011-05-01

    Hard turning with super hard cutting tools, like PCBN or Ceramics inserts, represents an interesting advance in the manufacturing industry, regarding the finishing of hardened steels. This innovative machining technique is considered an attractive alternative to traditional finish grinding operations because of the high flexibility, the ability to achieve higher metal removal rates, the possibility to operate without the use of coolants, and the capability to achieve comparable workpiece quality. However, the surface integrity effects of hard machining need to be taken into account due to their influence on the life of machined components. In particular, the formation of a usually undesirable white layer at the surface needs further investigation. Three different mechanisms have been proposed as main responsible of the white layer genesis: (i) microstructural phase transformation due to a rapid heating and quenching, (ii) severe plastic deformation resulting in a homogenous structure and/or a very fine grain size microstructure; (iii) surface reaction with the environment. In this research, an experimental campaign was carried out and several experimental techniques were used in order to analyzed the machined surface and to understand which of the above mentioned theories is the main cause of the white layer formation when AISI 52100 hardened steel is machined by PCBN inserts. In particular, the topography characterization has obtained by means of optical and scanning electron microscope (SEM) while microstructural phase composition and chemical characterization have been respectively detected using X-ray Diffraction (XRD) and Energy-dispersive X-ray spectroscopy (EDS) techniques. The results prove that the white layer is the result of microstructural alteration, i.e. the generation of a martensitic structure.

  15. Evaluate Potenial Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 2002 Annual Report.

    SciTech Connect

    Everett, Scott R.; Tuell, Michael A.; Hesse, Jay A.

    2004-02-01

    The specific research goal of this project is to identify means to restore and rebuild the Snake River white sturgeon (Acipenser transmontanus) population to support a sustainable annual subsistence harvest equivalent to 5 kg/ha/yr (CBFWA 1997). Based on data collected, a white sturgeon adaptive management plan will be developed. This report presents a summary of results from the 1997-2002 Phase II data collection and represents the end of phase II. From 1997 to 2001 white sturgeon were captured, marked, and population data were collected in the Snake and Salmon. A total of 1,785 white sturgeon were captured and tagged in the Snake River and 77 in the Salmon River. Since 1997, 25.8 percent of the tagged white sturgeon have been recaptured. Relative density of white sturgeon was highest in the free-flowing segment of the Snake River, with reduced densities of fish in Lower Granite Reservoir, and low densities the Salmon River. Differences were detected in the length frequency distributions of white sturgeon in Lower Granite Reservoir, the free-flowing Snake River and the Salmon River (Chi-Square test, P<0.05). The proportion of white sturgeon greater than 92 cm (total length) in the free-flowing Snake River has shown an increase of 30 percent since the 1970's. Using the Jolly-Seber model, the abundance of white sturgeon <60 cm, between Lower Granite Dam and the mouth of the Salmon River, was estimated at 2,483 fish, with a 95% confidence interval of 1,208-7,477. Total annual mortality rate was estimated to be 0.14 (95% confidence interval of 0.12 to 0.17). A total of 35 white sturgeon were fitted with radio-tags during 1999-2002. The movement of these fish ranged from 53 km (33 miles) downstream to 77 km (48 miles) upstream; however, 38.8 percent of the detected movement was less than 0.8 km (0.5 mile). Both radio-tagged fish and recaptured white sturgeon in Lower Granite Reservoir appear to move more than fish in the free-flowing segment of the Snake River. No

  16. North American sturgeon otolith morphology

    USGS Publications Warehouse

    Chalupnicki, Marc A.; Dittman, Dawn E.

    2016-01-01

    Accurate expedient species identification of deceased sturgeon (Acipenseridae) when external physical characteristic analysis is inconclusive has become a high priority due to the endangered or threatened status of sturgeon species around the world. Examination of otoliths has provided useful information to aid in population management, age and size-class analysis, understanding predator–prey interactions, and archeological research in other fish species. The relationship between otolith characteristics and sturgeon species has remained unknown. Therefore, we analyzed the shape of otoliths from the eight species of sturgeon found in North America to test the utility of otolith characteristic morphology in species identification. There were distinct differences in the size and shape of the otoliths between species of sturgeon with little shape variation among individuals of the same species. The relationship between otolith length axes was linear, and most of the variability was explained by a Log (axis + 1) transformation of the x and y axes (r2 = 0.8983) using the equation y = 0.73x + 0.0612. Images of otoliths from all eight North American species are presented to assist in the identification process.

  17. Ontogenetic behavior, migration, and social behavior of pallid sturgeon, Scaphirhynchus albus, and shovelnose sturgeon, S. platorynchus, with notes on the adaptive significance of body color

    USGS Publications Warehouse

    Kynard, B.; Henyey, E.; Horgan, M.

    2002-01-01

    We conducted laboratory studies on the ontogenetic behavior of free embryos (first life interval after hatching) and larvae (first feeding interval) of pallid and shovelnose sturgeon. Migration styles of both species were similar for timing of migration (initiation by embryos on day 0 after hatching and cessation by larvae on days 12-13 at 236-243 cumulative temperature degree units), migration distance (about 13 km), life interval when most distance was moved (embryo), and diel behavior of embryos (diurnal). However, the species differed for two behaviors: movement characteristics of embryos (peak movement rate of pallid sturgeon was only one-half the peak rate of shovelnose sturgeon, but pallid sturgeon continued the lower rate for twice as long) and diel behavior of larvae (pallid sturgeon were diurnal and shovelnose sturgeon were nocturnal). Thus, the species used different methods to move the same distance. Migrating as poorly developed embryos suggests a migration style to avoid predation at the spawning site, but moving from spawning habitat to rearing habitat before first feeding could also be important. Migrants of both species preferred bright habitat (high illumination intensity and white substrate), a behavioral preference that may characterize the migrants of many species of sturgeon. Both species were remarkably similar for swimming height above the bottom by age, and day 7 and older migrants may swim far above the bottom and move far downstream. A migration of 12 or 13 days will probably not distribute larvae throughout the population's range, so an older life interval likely initiates a second longer downstream migration (2-step migration). By day 2, individuals of both species were a black-tail phenotype (light grey body with a black-tail that moved conspicuously during swimming). Aggregation behavior suggests that black-tail is a visual signal used for group cohesion.

  18. Tracing the first steps of American sturgeon pioneers in Europe

    USGS Publications Warehouse

    Ludwig, A.; Arndt, U.; Lippold, S.; Benecke, N.; Debus, L.; King, T.L.; Matsumura, S.

    2008-01-01

    Background. A Baltic population of Atlantic sturgeon was founded ???1,200 years ago by migrants from North America, but after centuries of persistence, the population was extirpated in the 1960s, mainly as a result of over-harvest and habitat alterations. As there are four genetically distinct groups of Atlantic sturgeon inhabiting North American rivers today, we investigated the genetic provenance of the historic Baltic population by ancient DNA analyses using mitochondrial and nuclear markers. Results. The phylogeographic signal obtained from multilocus microsatellite DNA genotypes and mitochondrial DNA control region haplotypes, when compared to existing baseline datasets from extant populations, allowed for the identification of the region-of-origin of the North American Atlantic sturgeon founders. Moreover, statistical and simulation analyses of the multilocus genotypes allowed for the calculation of the effective number of individuals that originally founded the European population of Atlantic sturgeon. Our findings suggest that the Baltic population of A. oxyrinchus descended from a relatively small number of founders originating from the northern extent of the species' range in North America. Conclusion. These results demonstrate that the most northerly distributed North American A. oxyrinchus colonized the Baltic Sea ???1,200 years ago, suggesting that Canadian specimens should be the primary source of broodstock used for restoration in Baltic rivers. This study illustrates the great potential of patterns obtained from ancient DNA to identify population-of-origin to investigate historic genotype structure of extinct populations. ?? 2008 Ludwig et al; licensee BioMed Central Ltd.

  19. Chemical characteristics and antithrombotic effect of chondroitin sulfates from sturgeon skull and sturgeon backbone.

    PubMed

    Gui, Meng; Song, Juyi; Zhang, Lu; Wang, Shun; Wu, Ruiyun; Ma, Changwei; Li, Pinglan

    2015-06-01

    Chondroitin sulfates (CSs) were extracted from sturgeon skull and backbone, and their chemical composition, anticoagulant, anti-platelet and thrombolysis activities were evaluated. The average molecular weights of CS from sturgeon skull and backbone were 38.5kDa and 49.2kDa, respectively. Disaccharide analysis indicated that the sturgeon backbone CS was primarily composed of disaccharide monosulfated in position four of the GalNAc (37.8%) and disaccharide monosulfated in position six of the GalNAc (59.6%) while sturgeon skull CS was primarily composed of nonsulfated disaccharide (74.2%). Sturgeon backbone CS showed stronger antithrombotic effect than sturgeon skull CS. Sturgeon backbone CS could significantly prolong activated partial thromboplastin time (APTT) and thrombin time (TT), inhibited ADP-induced platelet aggregation and dissolved platelet plasma clots in vitro. The results suggested that sturgeon backbone CS can be explored as a functional food with antithrombotic function.

  20. 33 CFR 162.125 - Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: The Corps of Engineers also has regulations dealing with these areas in 33 CFR Part 207. ... Ship Canal, Wisc. 162.125 Section 162.125 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc. (a) In the Sturgeon Bay Ship Canal: (1) No vessel...

  1. Toxicity assessment of silver nanoparticles in Persian sturgeon (Acipenser persicus) and starry sturgeon (Acipenser stellatus) during early life stages.

    PubMed

    Banan, Ashkan; Kalbassi Masjed Shahi, Mohammad Reza; Bahmani, Mahmoud; Yazdani Sadati, Mohammad Ali

    2016-05-01

    Silver nanoparticles (AgNPs) are widely used in consumer products mainly due to their antimicrobial action. The rapidly increasing use of nanoparticles (NPs) has driven more attention to their possible ecotoxicological effects. In this study, the acute toxicity of colloidal AgNPs was evaluated during the embryonic stage of Persian sturgeon (Acipenser persicus) and starry sturgeon (Acipenser stellatus) at concentrations of 0, 0.25, 0.5, 1, 2, 4, and 8 mg/L. Fertilized eggs (75 eggs per replicate) were exposed to aforementioned concentrations for 96 h in triplicate. 96-h LC50 values in Persian sturgeon and starry sturgeon were calculated as 0.163 and 0.158 mg/L, respectively. Furthermore, in starry sturgeon, the short-term effects of AgNPs on the hatching rate, survival rate, and Ag accumulation during early life stages (before active feeding commences) were also analyzed at concentrations of 0, 0.025, 0.05, and 0.1 mg/L of colloidal AgNPs. The highest silver accumulation occurred in larvae exposed to 0.1 mg/L AgNPs; however, the body burden of silver did not alter survival rate, and there were no significant differences among treatments. Based on the obtained results from the acute toxicity exposures, AgNPs induced a concentration-dependent toxicity in both species during early life stages, while complementary studies are suggested for investigating their short-term effects in detail.

  2. Habitat use of juvenile pallid sturgeon and shovelnose sturgeon with implications for water-level management in a downstream reservoir

    USGS Publications Warehouse

    Gerrity, P.C.; Guy, C.S.; Gardner, W.M.

    2008-01-01

    Natural recruitment of pallid sturgeon Scaphirhynchus albus has not been observed in the Missouri River above Fort Peck Reservoir, Montana, for at least 20 years. To augment the population, age-1 hatchery-reared juvenile pallid sturgeon were released in 1998. The objective of this study was to evaluate the habitat use of these fish and compare it with that of indigenous shovelnose sturgeon S. platorynchus. Twenty-nine juvenile pallid sturgeon and 21 indigenous shovelnose sturgeon were implanted with radio transmitters in 2003 and 2004. The two species showed no differences in habitat use in terms of mean depth, cross-sectional relative depth, longitudinal relative depth, column velocity, bottom velocity, and channel width. However, there were seasonal differences within both species for cross-sectional relative depth, column velocity, and channel width. Both shovelnose sturgeon and juvenile pallid sturgeon were primarily associated with silt and sand substrate. However, shovelnose sturgeon were associated with gravel and cobble substrate more than juvenile pallid sturgeon. Shovelnose sturgeon and juvenile pallid sturgeon both selected reaches without islands and avoided reaches with islands; the two species also selected main-channel habitat and avoided secondary channels. Mean home range was similar between juvenile pallid sturgeon (15 km; 90% confidence interval, ??5.0 km) and shovelnose sturgeon (16.5 km; ??4.7 km). Spatial distribution differed between the two species, with shovelnose sturgeon using upstream areas more often than juvenile pallid sturgeon. Twenty-eight percent of juvenile pallid sturgeon frequented 60 km of lotie habitat that would be inundated by Fort Peck Reservoir at maximum pool. Stocking juvenile pallid sturgeon can successfully augment the wild pallid sturgeon population in the Missouri River above Fort Peck Reservoir, which is crucial to the long-term recovery of the species. However, water-level management in downstream reservoirs such

  3. Dual annual spawning races in Atlantic sturgeon.

    PubMed

    Balazik, Matthew T; Musick, John A

    2015-01-01

    Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus, Acipenseridae) populations in the United States were listed as either endangered or threatened under the Endangered Species Act in 2012. Because of the endangered/threatened status, a better understanding of Atlantic sturgeon life-history behavior and habitat use is important for effective management. It has been widely documented that Atlantic sturgeon reproduction occurs from late winter to early summer, varying clinally with latitude. However, recent data show Atlantic sturgeon also spawn later in the year. The group that spawns later in the year seems to be completely separate from the spring spawning run. Recognition of the later spawning season has drastically modified estimates of the population status of Atlantic sturgeon in Virginia. With the combination of new telemetry data and historical documentation we describe a dual spawning strategy that likely occurs in various degrees along most, if not all, of the Atlantic sturgeon's range. Using new data combined with historical sources, a new spawning strategy emerges which managers and researchers should note when determining the status of Atlantic sturgeon populations and implementing conservation measures.

  4. Dual Annual Spawning Races in Atlantic Sturgeon

    PubMed Central

    Balazik, Matthew T.; Musick, John A.

    2015-01-01

    Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus, Acipenseridae) populations in the United States were listed as either endangered or threatened under the Endangered Species Act in 2012. Because of the endangered/threatened status, a better understanding of Atlantic sturgeon life-history behavior and habitat use is important for effective management. It has been widely documented that Atlantic sturgeon reproduction occurs from late winter to early summer, varying clinally with latitude. However, recent data show Atlantic sturgeon also spawn later in the year. The group that spawns later in the year seems to be completely separate from the spring spawning run. Recognition of the later spawning season has drastically modified estimates of the population status of Atlantic sturgeon in Virginia. With the combination of new telemetry data and historical documentation we describe a dual spawning strategy that likely occurs in various degrees along most, if not all, of the Atlantic sturgeon's range. Using new data combined with historical sources, a new spawning strategy emerges which managers and researchers should note when determining the status of Atlantic sturgeon populations and implementing conservation measures. PMID:26020631

  5. Blacks' and Whites' Perceptions of Real-Life Scenarios: A Preliminary Investigation.

    ERIC Educational Resources Information Center

    Brinson, Jesse A.; Morris, Joseph R.

    2001-01-01

    This study investigated the perceptual differences between Black and White counselor trainees toward 12 real-life scenarios featuring Black and White individuals. The authors hypothesized that the two groups would differ in their perceptions of most of the scenarios. The results reveal significant differences in perceptions on 4 out of 12…

  6. 33 CFR 117.1101 - Sturgeon Bay.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... intended passage. (b) The draw of the Maple-Oregon Bridge, mile 4.17 at Sturgeon Bay, shall open on signal... the Maple-Oregon Street drawbridge, shall open simultaneously for larger commercial vessels, as...

  7. 33 CFR 117.1101 - Sturgeon Bay.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... intended passage. (b) The draw of the Maple-Oregon Bridge, mile 4.17 at Sturgeon Bay, shall open on signal... the Maple-Oregon Street drawbridge, shall open simultaneously for larger commercial vessels, as...

  8. Evidence of autumn spawning in Suwannee River Gulf sturgeon, Acipenser oxyrinchus desotoi (Vladykov, 1955)

    USGS Publications Warehouse

    Randall, M.T.; Sulak, K.J.

    2012-01-01

    Evidence of autumn spawning of Gulf sturgeon Acipenser oxyrinchus desotoi in the Suwannee River, Florida, was compiled from multiple investigations between 1986 and 2008. Gulf sturgeon are known from egg collections to spawn in the springtime months following immigration into rivers. Evidence of autumn spawning includes multiple captures of sturgeon in September through early November that were ripe (late-development ova; motile sperm) or exhibited just-spawned characteristics, telemetry of fish that made >175 river kilometer upstream excursions to the spawning grounds in September–October, and the capture of a 9.3 cm TL age-0 Gulf sturgeon on 29 November 2000 (which would have been spawned in late September 2000). Analysis of age-at-length data indicates that ca. 20% of the Suwannee River Gulf sturgeon population may be attributable to autumn spawning. However, with the very low sampling effort expended, eggs or early life stages have not yet been captured in the autumn, which would be the conclusive proof of autumn spawning. More sampling, and sampling at previously unknown sites frequented by acoustic telemetry fish, would be required to find eggs.

  9. Comparative ontogenetic behavior and migration of kaluga, Huso dauricus, and Amur sturgeon, Acipenser schrenckii, from the Amur River

    USGS Publications Warehouse

    Zhuang, P.; Kynard, B.; Zhang, L.; Zhang, T.; Cao, W.

    2003-01-01

    We conducted laboratory experiments with kaluga, Huso dauricus, and Amur sturgeon, Acipenser schrenckii, to develop a conceptual model of early behavior. We daily observed embryos (first life phase after hatching) and larvae (period initiating exogenous feeding) to day-30 (late larvae) for preference of bright habitat and cover, swimming distance above the bottom, up- and downstream movement, and diel activity. Day-0 embryos of both species strongly preferred bright, open habitat and initiated a strong, downstream migration that lasted 4 days (3 day peak) for kaluga and 3 days (2 day peak) for Amur sturgeon. Kaluga migrants swam far above the bottom (150 cm) on only 1 day and moved day and night; Amur sturgeon migrants swam far above the bottom (median 130 cm) during 3 days and were more nocturnal than kaluga. Post-migrant embryos of both species moved day and night, but Amur sturgeon used dark, cover habitat and swam closer to the bottom than kaluga. The larva period of both species began on day 7 (cumulative temperature degree-days, 192.0 for kaluga and 171.5 for Amur sturgeon). Larvae of both species preferred open habitat. Kaluga larvae strongly preferred bright habitat, initially swam far above the bottom (median 50-105 cm), and migrated downstream at night during days 10-16 (7-day migration). Amur sturgeon larvae strongly avoided illumination, had a mixed response to white substrate, swam 20-30 cm above the bottom during most days, and during days 12-34 (most of the larva period) moved downstream mostly at night (23-day migration). The embryo-larva migration style of the two species likely shows convergence of non-related species for a common style in response to environmental selection in the Amur River. The embryo-larva migration style of Amur sturgeon is unique among Acipenser yet studied.

  10. 77 FR 44140 - Drawbridge Operation Regulation; Sturgeon Bay Ship Canal, Sturgeon Bay, WI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-27

    ...; Sturgeon Bay Ship Canal, Sturgeon Bay, WI, in the Federal Register (77 FR 21890). We did not receive any... final rule was published on October 24, 2005 in the Federal Register (70 FR 61380) to allow for one... published on June 5, 2009 in the Federal Register (74 FR 26954), effective from June 1, 2009 to November...

  11. Technical note: Production of tetraploid sturgeons.

    PubMed

    Lebeda, I; Flajshans, M

    2015-08-01

    Studies and practical application of androgenesis and gynogenesis in sturgeon are significantly hindered by strong influence of ploidy restoration treatment on survivability of progeny; therefore, developed method of production of tetraploid broodstock and, consequently, use of their diploid gametes might help to avoid ploidy restoration treatment. In the present study, for the first time was developed a protocol for tetraploidy induction in 2 model sturgeon species, sterlet () and Siberian sturgeon (). A high efficiency of treatment was achieved by optimization of heat shock using a temperature of 37°C for 2 min timed between the end of female pronuclei formation and the beginning of pronuclei migration, that is, 0.8 to 1.0 τ (duration of 1 mitotic cycle during the period of synchronous cleavage division). Fertilized eggs developed in tetraploid larvae, up to 31 (89.6% in control) and 34% (70.9% in control) in sterlet and Siberian sturgeon, respectively. Most of the tetraploid larvae exhibited body malformations; as a result, consequent large scale study revealed high larval mortality, which drastically decreased after 2 mo of age. Consequent comparison of BW, length, and malformation rate and mortality between diploid and tetraploid progeny of sterlet did not reveal significant differences in fitness of diploid and tetraploid juveniles at 9 and 11 mo of age. The present study can be considered the first step towards improving the androgenesis methods of conservation of endangered sturgeons as well as understanding the sturgeon sex determination system through induction of mitotic gynogenesis.

  12. Exposure of Persian sturgeon (Acipenser persicus) to cadmium results in biochemical, histological and transcriptional alterations.

    PubMed

    Miandare, Hamed Kolangi; Niknejad, Mahtab; Shabani, Ali; Safari, Roghieh

    2016-01-01

    Sturgeon is one of the endangered families of fish in the Caspian Sea region, where there is up to 80% of their global caching. Unfortunately, in recent years, increase of pollutants has been resulted in their total population reduction. Due to their benthic nature, sturgeons are at great risk of exposing to contaminants such as cadmium. Despite their endangered status in the Caspian Sea, there are only a few studies on characterizing the relative sensitivity of sturgeons to cadmium. Adverse effects associated with pollution on angiogenesis are mediated by hypoxia inducing factor-1 (HIF-1) and vascular endothelial growth factor (VEGF). In this investigation, gene expression of two distinct HIFs-1, HIF-1α and HIF-2α, and VEGF was investigated at the mRNA transcript levels after exposure of Persian sturgeon (Acipenser persicus) to cadmium. VEGF, HIF-1α and HIF-2α expressions in treated Persian sturgeon were greater than controls. Significant increases (P<0.05) were also observed in cortisol and glucose levels compared to the control group especially in the fish exposed to higher cadmium concentration (800 μg/L). Plasma aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactic acid dehydrogenase (LDH) levels were increased in the cadmium-exposed fish, although the observed increases were not significant between the control and 200 μg/L cadmium treatment at some sampling time points. Gill tissues also showed histopathological changes in the cadmium treatments. Overall, results indicated that cadmium resulted in some alterations in biochemical parameters, mRNA transcript level expression of two important angiogenesis related genes as well as histological alterations in Persian sturgeon.

  13. Potential for electropositive metal to reduce the interactions of Atlantic sturgeon with fishing gear.

    PubMed

    Bouyoucos, Ian; Bushnell, Peter; Brill, Richard

    2014-02-01

    Atlantic sturgeon (Acipenser oxyrhynchus) populations have been declared either endangered or threatened under the U.S. Endangered Species Act. Effective measures to repel sturgeon from fishing gear would be beneficial to both fish and fishers because they could reduce both fishery-associated mortality and the need for seasonal and area closures of specific fisheries. Some chondrostean fishes (e.g., sturgeons and paddlefishes) can detect weak electric field gradients (possibly as low as 5 Μv/cm) due to arrays of electroreceptors (ampullae of Lorenzini) on their snout and gill covers. Weak electric fields, such as those produced by electropositive metals (typically mixtures of the lanthanide elements), could therefore potentially be used as a deterrent. To test this idea, we recorded the behavioral responses of juvenile Atlantic sturgeon (31-43 cm fork length) to electropositive metal (primarily a mixture of the lanthanide elements neodymium and praseodymium) both in the presence and absence of food stimuli. Trials were conducted in an approximately 2.5 m diameter × 0.3 m deep tank, and fish behaviors were recorded with an overhead digital video camera. Video records were subsequently digitized (x, y coordinate system), the distance between the fish and the electropositive metal calculated, and data summarized by compiling frequency distributions with 5-cm bins. Juvenile sturgeon showed clear avoidance of electropositive metal but only when food was present. On the basis of our results, we conclude that the electropositive metals, or other sources of weak electric fields, may eventually be used to reduce the interactions of Atlantic sturgeon with fishing gear, but further investigation is needed.

  14. Potential for electropositive metal to reduce the interactions of Atlantic sturgeon with fishing gear.

    PubMed

    Bouyoucos, Ian; Bushnell, Peter; Brill, Richard

    2014-02-01

    Atlantic sturgeon (Acipenser oxyrhynchus) populations have been declared either endangered or threatened under the U.S. Endangered Species Act. Effective measures to repel sturgeon from fishing gear would be beneficial to both fish and fishers because they could reduce both fishery-associated mortality and the need for seasonal and area closures of specific fisheries. Some chondrostean fishes (e.g., sturgeons and paddlefishes) can detect weak electric field gradients (possibly as low as 5 Μv/cm) due to arrays of electroreceptors (ampullae of Lorenzini) on their snout and gill covers. Weak electric fields, such as those produced by electropositive metals (typically mixtures of the lanthanide elements), could therefore potentially be used as a deterrent. To test this idea, we recorded the behavioral responses of juvenile Atlantic sturgeon (31-43 cm fork length) to electropositive metal (primarily a mixture of the lanthanide elements neodymium and praseodymium) both in the presence and absence of food stimuli. Trials were conducted in an approximately 2.5 m diameter × 0.3 m deep tank, and fish behaviors were recorded with an overhead digital video camera. Video records were subsequently digitized (x, y coordinate system), the distance between the fish and the electropositive metal calculated, and data summarized by compiling frequency distributions with 5-cm bins. Juvenile sturgeon showed clear avoidance of electropositive metal but only when food was present. On the basis of our results, we conclude that the electropositive metals, or other sources of weak electric fields, may eventually be used to reduce the interactions of Atlantic sturgeon with fishing gear, but further investigation is needed. PMID:24372943

  15. Sex assignment of lake sturgeon (Acipenser fluvescens) based on plasma sex hormone and vitellogenin levels

    USGS Publications Warehouse

    Craig, J.M.; Papoulias, D.M.; Thomas, M.V.; Annis, M.L.; Boase, J.

    2009-01-01

    This study focused on identifying the sex of lake sturgeon by measuring the sex hormones estradiol and testosterone, and the phosphoprotein vitellogenin (Vtg) in blood plasma by radioimmunoassay and enzyme-linked immunosorbent assay, respectively, and evaluating these techniques as tools in lake sturgeon population management. Surveys of the St Clair River (SCR) lake sturgeon population have characterized it as rebounding by having steady or increasing recruitment since 1997. However, researchers have not been able to effectively determine the sex for most of the sturgeon they capture because few fish caught during surveys are releasing gametes. A total of 115 fish were sampled from May through June in 2004 and 2005 from the SCR, Michigan, USA. Of these, only four females and eight males were verified (i.e. they were releasing gametes at time of capture), resulting in very few fish with which to validate blood hormone and Vtg biomarkers of sex. Fifty-six percent of the fish were assigned a sex designation based on biomarker criteria. Correspondence between actual gonadal sex and biomarker-directed classification was good for the small subset of fish for which gonadal sex was definitively determined. Moreover, application of the steroid values in a predictive sex assignment model developed for white sturgeon misclassified only the same two fish that were misclassified with the steroid and Vtg biomarkers. The experimental results suggest a sex ratio of 1 : 2.7 (F:M), however more conclusive methods are needed to confirm this ratio because so few fish were available for sex validation. Of the 43 males, 14 were within the legal slot limit, 11 were smaller than 1067 mm total length (TL), and 18 were larger than 1270 mm TL. All 15 females were larger than 1270 mm TL, and thus protected by the slot limit criteria. Considering that lake sturgeon are threatened in Michigan, an advantage to using blood plasma assays was that fish were not harmed, and sample collection was

  16. Lake sturgeon population characteristics in Rainy Lake, Minnesota and Ontario

    USGS Publications Warehouse

    Adams, W.E.; Kallemeyn, L.W.; Willis, D.W.

    2006-01-01

    Rainy Lake contains a native population of lake sturgeon Acipenser fulvescens that has been largely unstudied. The aims of this study were to document the population characteristics of lake sturgeon in Rainy Lake and to relate environmental factors to year-class strength for this population. Gill-netting efforts throughout the study resulted in the capture of 322 lake sturgeon, including 50 recaptures. Lake sturgeon in Rainy Lake was relatively plump and fast growing compared with a 32-population summary. Population samples were dominated by lake sturgeon between 110 and 150 cm total length. Age–structure analysis of the samples indicated few younger (<10 years) lake sturgeon, but the smallest gill net mesh size used for sampling was 102 mm (bar measure) and would not retain small sturgeon. Few lake sturgeon older than age 50 years were captured, and maximum age of sampled fish was 59 years. Few correlations existed between lake sturgeon year-class indices and both annual and monthly climate variables, except that mean June air temperature was positively correlated with year-class strength. Analysis of Rainy Lake water elevation and resulting lake sturgeon year-class strength indices across years yielded consistent but weak negative correlations between late April and early June, when spawning of lake sturgeon occurs. The baseline data collected in this study should allow Rainy Lake biologists to establish more specific research questions in the future.

  17. A comprehensive investigation on CVD growth thermokinetics of h-BN white graphene

    NASA Astrophysics Data System (ADS)

    Song, Xiufeng; Li, Qiguang; Ji, Jianping; Yan, Zhong; Gu, Yu; Huo, Chengxue; Zou, Yousheng; Zhi, Chunyi; Zeng, Haibo

    2016-09-01

    As an isomorph of graphene, monolayer hexagonal boron nitride (h-BN), so-called white graphene, has been in the spotlight of two-dimensional materials due to its outstanding properties. However, the growth of large and uniform white graphene monocrystalline with low density of defects is still a great challenge. Here, we present a comprehensive investigation on the growth thermokinetics of white graphene monocrystalline domains via atmospheric pressure chemical vapor deposition with the solid ammonia borane as precursors, which will be more suitable for future industrial production due to the handy process and precursor. The single domain size, coverage on substrate, and thickness of white graphene were taken as targeted parameters of products. And then, their dependences on the flow rate of carrier gas, heating temperature of ammonia borane, growth temperature and time were studied in details. Finally, after optimizing the above conditions, both white graphene monocrystalline domains as large as 80 μm2 and polycrystalline ultrathin film with coverage ratio of 95%-100% can be achieved facilely without using vacuum technique. Such white graphene products would be of great significance for the tunnel barrier for the tunneling transistor and the dielectric layers for nanocapacitor with the graphene based heterostructures.

  18. A comprehensive investigation on CVD growth thermokinetics of h-BN white graphene

    NASA Astrophysics Data System (ADS)

    Song, Xiufeng; Li, Qiguang; Ji, Jianping; Yan, Zhong; Gu, Yu; Huo, Chengxue; Zou, Yousheng; Zhi, Chunyi; Zeng, Haibo

    2016-09-01

    As an isomorph of graphene, monolayer hexagonal boron nitride (h-BN), so-called white graphene, has been in the spotlight of two-dimensional materials due to its outstanding properties. However, the growth of large and uniform white graphene monocrystalline with low density of defects is still a great challenge. Here, we present a comprehensive investigation on the growth thermokinetics of white graphene monocrystalline domains via atmospheric pressure chemical vapor deposition with the solid ammonia borane as precursors, which will be more suitable for future industrial production due to the handy process and precursor. The single domain size, coverage on substrate, and thickness of white graphene were taken as targeted parameters of products. And then, their dependences on the flow rate of carrier gas, heating temperature of ammonia borane, growth temperature and time were studied in details. Finally, after optimizing the above conditions, both white graphene monocrystalline domains as large as 80 μm2 and polycrystalline ultrathin film with coverage ratio of 95%–100% can be achieved facilely without using vacuum technique. Such white graphene products would be of great significance for the tunnel barrier for the tunneling transistor and the dielectric layers for nanocapacitor with the graphene based heterostructures.

  19. Bycatch of the endangered pallid sturgeon (Scaphirhynchus albus) in a commercial fishery for shovelnose sturgeon (Scaphirhynchus platorynchus)

    USGS Publications Warehouse

    Bettoli, Phillip William; Casto-Yerty, M.; Scholten, G.D.; Heist, Edward J.

    2009-01-01

    We quantified the bycatch of pallid sturgeon Scaphirhynchus albus in Tennessee's shovelnose sturgeon (Scaphirhynchus platorynchus) fishery by accompanying commercial fishers and monitoring their catch on five dates in spring 2007. Fishers were free to keep or discard any sturgeon they collected in their gillnets and trotlines and we were afforded the opportunity to collect meristic and morphometric data and tissue samples from discarded and harvested specimens. Fishers removed 327 live sturgeon from their gear in our presence, of which 93 were harvested; we also obtained the carcasses of 20 sturgeon that a fisher harvested out of our sight while we were on the water with another fisher. Two of the 113 harvested sturgeon were confirmed pallid sturgeon based on microsatellite DNA analyses. Additionally, fishers gave us five, live pallid sturgeon that they had removed from their gear. If the incidental harvest rate of pallid sturgeon (1.8% of all sturgeon harvested) was similar in the previous two commercial seasons, at least 169 adult pallid sturgeon were harvested by commercial fishers in the Tennessee waters of the Mississippi River in 2005-2007. If fishers altered their behavior because of our presence (i.e. if they were more conservative in what they harvested), the pallid sturgeon take was probably higher when they fished unaccompanied by observers. While retrieving a gill net set the previous day, a fisher we were accompanying retrieved a gillnet lost 2 days earlier; this ghost net caught 53 sturgeon whereby one fish was harvested but most fish were dead, including one confirmed pallid sturgeon.

  20. Bycatch of the endangered pallid sturgeon (Scaphirhynchus albus) in a commercial fishery for shovelnose sturgeon (Scaphirhynchus platorynchus)

    USGS Publications Warehouse

    Bettoli, P.W.; Casto-Yerty, M.; Scholten, G.D.; Heist, E.J.

    2009-01-01

    We quantified the bycatch of pallid sturgeon Scaphirhynchus albus in Tennessee's shovelnose sturgeon (Scaphirhynchus platorynchus) fishery by accompanying commercial fishers and monitoring their catch on five dates in spring 2007. Fishers were free to keep or discard any sturgeon they collected in their gillnets and trotlines and we were afforded the opportunity to collect meristic and morphometric data and tissue samples from discarded and harvested specimens. Fishers removed 327 live sturgeon from their gear in our presence, of which 93 were harvested; we also obtained the carcasses of 20 sturgeon that a fisher harvested out of our sight while we were on the water with another fisher. Two of the 113 harvested sturgeon were confirmed pallid sturgeon based on microsatellite DNA analyses. Additionally, fishers gave us five, live pallid sturgeon that they had removed from their gear. If the incidental harvest rate of pallid sturgeon (1.8% of all sturgeon harvested) was similar in the previous two commercial seasons, at least 169 adult pallid sturgeon were harvested by commercial fishers in the Tennessee waters of the Mississippi River in 2005-2007. If fishers altered their behavior because of our presence (i.e. if they were more conservative in what they harvested), the pallid sturgeon take was probably higher when they fished unaccompanied by observers. While retrieving a gill net set the previous day, a fisher we were accompanying retrieved a gillnet lost 2 days earlier; this ghost net caught 53 sturgeon whereby one fish was harvested but most fish were dead, including one confirmed pallid sturgeon. ?? 2008 Blackwell Verlag, Berlin.

  1. Fusion of white and gray matter geometry: a framework for investigating brain development.

    PubMed

    Savadjiev, Peter; Rathi, Yogesh; Bouix, Sylvain; Smith, Alex R; Schultz, Robert T; Verma, Ragini; Westin, Carl-Fredrik

    2014-12-01

    Current neuroimaging investigation of the white matter typically focuses on measurements derived from diffusion tensor imaging, such as fractional anisotropy (FA). In contrast, imaging studies of the gray matter oftentimes focus on morphological features such as cortical thickness, folding and surface curvature. As a result, it is not clear how to combine findings from these two types of approaches in order to obtain a consistent picture of morphological changes in both gray and white matter. In this paper, we propose a joint investigation of gray and white matter morphology by combining geometrical information from white and the gray matter. To achieve this, we first introduce a novel method for computing multi-scale white matter tract geometry. Its formulation is based on the differential geometry of curve sets and is easily incorporated into a continuous scale-space framework. We then incorporate this method into a novel framework for "fusing" white and gray matter geometrical information. Given a set of fiber tracts originating in a particular cortical region, the key idea is to compute two scalar fields that represent geometrical characteristics of the white matter and of the surface of the cortical region. A quantitative marker is created by combining the distributions of these scalar values using Mutual Information. This marker can be then used in the study of normal and pathological brain structure and development. We apply this framework to a study on autism spectrum disorder in children. Our preliminary results support the view that autism may be characterized by early brain overgrowth, followed by reduced or arrested growth (Courchesne, 2004).

  2. Investigations of White Layer Formation During Machining of Powder Metallurgical Ni-Based ME 16 Superalloy

    NASA Astrophysics Data System (ADS)

    Veldhuis, S. C.; Dosbaeva, G. K.; Elfizy, A.; Fox-Rabinovich, G. S.; Wagg, T.

    2010-10-01

    Surface integrity of machined parts made from the advanced Ni-based superalloys is important for modern manufacturing in the aerospace industry. Metallographic observations of the ME 16 alloy microstructure were made using optical metallography and a high-resolution scanning electron microscope with energy dispersive x-ray spectrometer (HR SEM/EDS). Tool life of cemented carbide inserts with TiAlN coating during machining (finishing turning operation) of ME 16 superalloy has been studied and wear patterns of the cutting tools were identified. Surface integrity of the machined part after completion of the turning operation was investigated. The morphology of machined parts has been examined and cross-sections of the machined surfaces have been analyzed. The formation of white layer on the surface of the machined part was studied for varied machining conditions. It was found that a 2-4 µm thick white layer forms during turning of the ME 16 superalloy. This layer was investigated using EDS and XRD. The studies show that the white layer is an oxygen-containing layer with a high amount of aluminum, enriched by chromium and tungsten. Under specific cutting conditions, the structure of white layer transforms into a γ-alumina. Formation of this thermal barrier ceramic white layer on the surface of the machined part negatively affects its surface integrity and cutting tool life.

  3. Control of sturgeon sperm motility: Antagonism between K+ ions concentration and osmolality.

    PubMed

    Prokopchuk, Galina; Dzyuba, Borys; Rodina, Marek; Cosson, Jacky

    2016-01-01

    Spermatozoa are stored in a quiescent state in the male reproductive tract and motility is induced in response to various environmental stimuli, such as change of osmolality (general case) and a decrease of extracellular K+ in fish from Acipenseridae family. This study was aimed to investigate the relationship between osmolality and extracellular K+ concentration in controlling sperm motility in sturgeon. Pre-incubation of sturgeon sperm for 5s in hypertonic solutions of glycerol, NaCl, or sucrose (each of 335 mOsm/kg osmolality) prepares sturgeon spermatozoa to become fully motile in presence of high concentration of K+ ions (15 mM), which has previously been demonstrated to fully repress motility. Furthermore, presence of 0.5mM KCl during the high osmolality pre-incubation exposure completely prevented subsequent spermatozoa activation in a K+-rich media. Manipulating the transport of K+ ions by the presence of K+ ionophore (valinomycin), it was concluded that once an efflux of K+ ions, the precursor of sturgeon sperm motility activation, is taking place, spermatozoa then become insensitive to a large extracellular K+ concentration.

  4. Ontogenetic behavior and migration of Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus, and shortnose sturgeon, A. brevirostrum, with notes on social behavior

    USGS Publications Warehouse

    Kynard, B.; Horgan, M.

    2002-01-01

    Ontogenetic behavior of Hudson River Atlantic sturgeon and Connecticut River shortnose sturgeon early life intervals were similar during laboratory observations. After hatching, free embryos were photonegative and sought cover. When embryos developed into larvae, fish left cover, were photopositive, and initiated downstream migration. Free embryos may remain at the spawning site instead of migrating downstream because the risk of predation at spawning sites is low. The two species are sympatric, but not closely related, so the similarities in innate behaviors suggest common adaptations, not phylogenetlc relationship. Atlantic sturgeon migrated downstream for 12 days (peak, first 6 days), shortnose sturgeon migrated for 3 days, and year-0 juveniles of both species did not resume downstream migration. Short or long migrations of larvae may reflect different styles related to the total migratory distance from spawning sites to juvenile rearing areas. Atlantic sturgeon need to move a short distance to reach rearing areas and they had a long 1-step migration of 6-12 days. In contrast, shortnose sturgeon need to move a long distance to reach all rearing areas. This may be accomplished by a 2-step migration, of which the brief migration of larvae is only the first step. Early migrant Atlantic sturgeon were nocturnal, while late migrants were diurnal, and shortnose sturgeon were diurnal. These diel differences may also be adaptations for long (Atlantic sturgeon) or short (shortnose sturgeon) migrations. Cultured shortnose sturgeon, and possibly Atlantic sturgeon, have a dominance hierarchy with large fish dominant when competing for limited foraging space. Social behavior may be more important in the life history of wild sturgeons than is generally recognized.

  5. Drift dynamics of larval pallid sturgeon and shovelnose sturgeon in a natural side channel of the Upper Missouri River, Montana

    USGS Publications Warehouse

    Braaten, P.J.; Fuller, D.B.; Holte, L.D.; Lott, R.D.; Viste, W.; Brandt, T.F.; Legare, R.G.

    2008-01-01

    The drift dynamics of larval shovelnose sturgeon Scaphirhynchus platorynchus (1, 2, 6, and 10 d posthatch [dph]) and pallid sturgeon S. albus (1, 2, 5, 9, 11, and 17 dph) were examined in a natural side channel of the Missouri River to quantify the vertical drift location of larvae in the water column, determine the drift velocity of larvae relative to water velocity, and simulate the cumulative distance (km) drifted by larvae during ontogenetic development. Larvae were released at the side-channel inlet and sampled at points 100, 500, 900, and 1,300 m downstream. Larvae drifted primarily near the riverbed, as 58-79% of recaptured shovelnose sturgeon and 63-89% of recaptured pallid sturgeon were sampled in the lower 0.5 m of the water column. The transition from the drifting to the benthic life stage was initiated at 6 dph (mean length, 15.6 mm) for shovelnose sturgeon and at 11-17 dph (mean length, 18.1-20.3 mm) for pallid sturgeon. Across ages, the drift rates of larval shovelnose sturgeon averaged 0.09-0.16 m/s slower than the mean water column velocity. The drift rates of pallid sturgeon were similar to or slightly slower (0.03-0.07 m/s) than the mean water column velocity for 1-11-dph larvae. Conversely, 17-dph larval pallid sturgeon dispersed downstream at a much slower rate (mean, 0.20 m/s slower than the mean water column velocity) owing to their transition to benthic habitats. Drift simulations indicated that the average larval shovelnose sturgeon may drift from 94 to 250 km and the average larval pallid sturgeon may drift from 245 to 530 km, depending on water velocity. Differences in larval drift dynamics between species provide a possible explanation for differences in recruitment between shovelnose sturgeon and pallid sturgeon in the upper Missouri River. ?? Copyright by the American Fisheries Society 2008.

  6. The history of sturgeon in the Baltic Sea

    USGS Publications Warehouse

    Popovic, Danijela; Panagiotopoulou, Hanna; Baca, Mateusz; Stefaniak, Krzysztof; Mackiewicz, Pawel; Makowiecki, Daniel; King, Tim L.; Gruchota, Jakub; Weglenski, Piotr; Stankovic, Anna

    2014-01-01

    For the past 2000 years at least, A. o. oxyrinchus has been the dominant sturgeon in the Baltic Sea, indicating a much earlier origin than previously suggested. The most similar extant sturgeon populations to the extinct Baltic stock are those from the St John and St Lawrence rivers in Canada. These populations should be considered the best source of breeding material for the ongoing sturgeon restitution programmes in Poland and Germany.

  7. Population viability analysis of Lower Missouri River shovelnose sturgeon with initial application to the pallid sturgeon

    USGS Publications Warehouse

    Bajer, P.G.; Wildhaber, M.L.

    2007-01-01

    Demographic models for the shovelnose (Scaphirhynchus platorynchus) and pallid (S. albus) sturgeons in the Lower Missouri River were developed to conduct sensitivity analyses for both populations. Potential effects of increased fishing mortality on the shovelnose sturgeon were also evaluated. Populations of shovelnose and pallid sturgeon were most sensitive to age-0 mortality rates as well as mortality rates of juveniles and young adults. Overall, fecundity was a less sensitive parameter. However, increased fecundity effectively balanced higher mortality among sensitive age classes in both populations. Management that increases population-level fecundity and improves survival of age-0, juveniles, and young adults should most effectively benefit both populations. Evaluation of reproductive values indicated that populations of pallid sturgeon dominated by ages ???35 could rapidly lose their potential for growth, particularly if recruitment remains low. Under the initial parameter values portraying current conditions the population of shovelnose sturgeon was predicted to decline by 1.65% annually, causing the commercial yield to also decline. Modeling indicated that the commercial yield could increase substantially if exploitation of females in ages ???12 was highly restricted. ?? 2007 Blackwell Verlag.

  8. Population viability analysis of Lower Missouri River shovelnose sturgeon with initial application to the pallid sturgeon

    USGS Publications Warehouse

    Bajer, P.G.; Wildhaber, M.L.

    2007-01-01

    Demographic models for the shovelnose (Scaphirhynchus platorynchus) and pallid (S. albus) sturgeons in the Lower Missouri River were developed to conduct sensitivity analyses for both populations. Potential effects of increased fishing mortality on the shovelnose sturgeon were also evaluated. Populations of shovelnose and pallid sturgeon were most sensitive to age-0 mortality rates as well as mortality rates of juveniles and young adults. Overall, fecundity was a less sensitive parameter. However, increased fecundity effectively balanced higher mortality among sensitive age classes in both populations. Management that increases population-level fecundity and improves survival of age-0, juveniles, and young adults should most effectively benefit both populations. Evaluation of reproductive values indicated that populations of pallid sturgeon dominated by ages ≥35 could rapidly lose their potential for growth, particularly if recruitment remains low. Under the initial parameter values portraying current conditions the population of shovelnose sturgeon was predicted to decline by 1.65% annually, causing the commercial yield to also decline. Modeling indicated that the commercial yield could increase substantially if exploitation of females in ages ≤12 was highly restricted.

  9. Coherent Scattering Investigations at the Spallation Neutron Source: a Snowmass White Paper

    SciTech Connect

    Akimov, D.; Bernstein, A.; BarbeauP.,; Barton, P. J.; Bolozdynya, A.; Cabrera-Palmer, B.; Cavanna, F.; Cianciolo, Vince; Collar, J.; Cooper, R. J.; Dean, D. J.; Efremenko, Yuri; Etenko, A.; Fields, N.; Foxe, M.; Figueroa-Feliciano, E.; Fomin, N.; Gallmeier, F.; Garishvili, I.; Gerling, M.; Green, M.; Greene, Geoffrey; Hatzikoutelis, A.; Henning, Reyco; Hix, R.; Hogan, D.; Hornback, D.; Jovanovic, I.; Hossbach, T.; Iverson, Erik B; Klein, S. R.; Khromov, A.; Link, J.; Louis, W.; Lu, W.; Mauger, C.; Marleau, P.; Markoff, D.; Martin, R. D.; Mueller, Paul Edward; Newby, J.; Orrell, John L.; O'Shaughnessy, C.; Penttila, Seppo; Patton, K.; Poon, A. W.; Radford, David C; Reyna, D.; Ray, H.; Scholberg, K.; Sosnovtsev, V.; Tayloe, R.; Vetter, K.; Virtue, C.; Wilkerson, J.; Yoo, J.; Yu, Chang-Hong

    2013-01-01

    The Spallation Neutron Source (SNS) at Oak Ridge National Laboratory, Tennessee, provides an intense flux of neutrinos in the few tens-of-MeV range, with a sharply-pulsed timing structure that is beneficial for background rejection. In this white paper, we describe how the SNS source can be used for a measurement of coherent elastic neutrino-nucleus scattering (CENNS), and the physics reach of different phases of such an experimental program (CSI: Coherent Scattering Investigations at the SNS).

  10. Green Sturgeon Physical Habitat Use in the Coastal Pacific Ocean

    PubMed Central

    Huff, David D.; Lindley, Steven T.; Rankin, Polly S.; Mora, Ethan A.

    2011-01-01

    The green sturgeon (Acipenser medirostris) is a highly migratory, oceanic, anadromous species with a complex life history that makes it vulnerable to species-wide threats in both freshwater and at sea. Green sturgeon population declines have preceded legal protection and curtailment of activities in marine environments deemed to increase its extinction risk. Yet, its marine habitat is poorly understood. We built a statistical model to characterize green sturgeon marine habitat using data from a coastal tracking array located along the Siletz Reef near Newport, Oregon, USA that recorded the passage of 37 acoustically tagged green sturgeon. We classified seafloor physical habitat features with high-resolution bathymetric and backscatter data. We then described the distribution of habitat components and their relationship to green sturgeon presence using ordination and subsequently used generalized linear model selection to identify important habitat components. Finally, we summarized depth and temperature recordings from seven green sturgeon present off the Oregon coast that were fitted with pop-off archival geolocation tags. Our analyses indicated that green sturgeon, on average, spent a longer duration in areas with high seafloor complexity, especially where a greater proportion of the substrate consists of boulders. Green sturgeon in marine habitats are primarily found at depths of 20–60 meters and from 9.5–16.0°C. Many sturgeon in this study were likely migrating in a northward direction, moving deeper, and may have been using complex seafloor habitat because it coincides with the distribution of benthic prey taxa or provides refuge from predators. Identifying important green sturgeon marine habitat is an essential step towards accurately defining the conditions that are necessary for its survival and will eventually yield range-wide, spatially explicit predictions of green sturgeon distribution. PMID:21966442

  11. Green sturgeon physical habitat use in the coastal Pacific Ocean.

    PubMed

    Huff, David D; Lindley, Steven T; Rankin, Polly S; Mora, Ethan A

    2011-01-01

    The green sturgeon (Acipenser medirostris) is a highly migratory, oceanic, anadromous species with a complex life history that makes it vulnerable to species-wide threats in both freshwater and at sea. Green sturgeon population declines have preceded legal protection and curtailment of activities in marine environments deemed to increase its extinction risk. Yet, its marine habitat is poorly understood. We built a statistical model to characterize green sturgeon marine habitat using data from a coastal tracking array located along the Siletz Reef near Newport, Oregon, USA that recorded the passage of 37 acoustically tagged green sturgeon. We classified seafloor physical habitat features with high-resolution bathymetric and backscatter data. We then described the distribution of habitat components and their relationship to green sturgeon presence using ordination and subsequently used generalized linear model selection to identify important habitat components. Finally, we summarized depth and temperature recordings from seven green sturgeon present off the Oregon coast that were fitted with pop-off archival geolocation tags. Our analyses indicated that green sturgeon, on average, spent a longer duration in areas with high seafloor complexity, especially where a greater proportion of the substrate consists of boulders. Green sturgeon in marine habitats are primarily found at depths of 20-60 meters and from 9.5-16.0°C. Many sturgeon in this study were likely migrating in a northward direction, moving deeper, and may have been using complex seafloor habitat because it coincides with the distribution of benthic prey taxa or provides refuge from predators. Identifying important green sturgeon marine habitat is an essential step towards accurately defining the conditions that are necessary for its survival and will eventually yield range-wide, spatially explicit predictions of green sturgeon distribution.

  12. STURGEON RIVER WILDERNESS STUDY AREA, MICHIGAN.

    USGS Publications Warehouse

    Cannon, W.F.; Hill, James J.

    1984-01-01

    A mineral survey of the Sturgeon River Wilderness study area, Michigan was made using geologic mapping and geochemical techniques. Previous geophysical studies were incorporated in the mineral assessment. The area and surroundings became the focus of intense uranium exploration as the result of major discoveries of a newly recognized type of deposit found in Australia and Canada in rocks very similar to those in the study area. The exploration was unsuccessful.

  13. 50 CFR 223.210 - North American green sturgeon.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false North American green sturgeon. 223.210... Applicable to Threatened Marine and Anadromous Species § 223.210 North American green sturgeon. (a... endangered species apply to the threatened Southern Distinct Population Segment (DPS) of North American...

  14. Salinity effects on Atlantic sturgeon growth and osmoregulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus Mitchill, 1815) is an anadromous sturgeon species, yet little is known with regard to its osmoregulatory ability and habitat use at early life stages. In order to examine whether salinity poses a physiological challenge to juvenile Atlantic stur...

  15. Chemical composition of blood and bile of the shovelnose sturgeon

    USGS Publications Warehouse

    Hunn, J.B.; Christenson, L.M.

    1977-01-01

    Samples of gallbladder bile and blood from shovelnose sturgeons (Scaphirhynchus platorynchus) collected from the Chippewa River, Wisconsin, contained concentrations of Na+, K+, Ca++, Mg++, Cl-, inorganic phosphate, and total cholesterol closely comparable with those reported for similar samples from other species of freshwater sturgeons.

  16. The Collective Construction of Middle-Class White Womanhood: Investigations of Teaching and Teacher Professionalization in a Diverse Elementary School

    ERIC Educational Resources Information Center

    Yoon, Irene H.

    2011-01-01

    This dissertation investigates how the intersections of race, class, and gender operate in the everyday teaching and professional norms of middle-class White women teachers--particularly in schools such as the one in this study, where a majority of middle-class, White women teachers serve predominantly low-income, racially and ethnically diverse…

  17. White Matter Microstructure in Transsexuals and Controls Investigated by Diffusion Tensor Imaging

    PubMed Central

    Kranz, Georg S.; Hahn, Andreas; Kaufmann, Ulrike; Küblböck, Martin; Hummer, Allan; Ganger, Sebastian; Seiger, Rene; Winkler, Dietmar; Swaab, Dick F.; Windischberger, Christian; Kasper, Siegfried; Lanzenberger, Rupert

    2015-01-01

    Biological causes underpinning the well known gender dimorphisms in human behavior, cognition, and emotion have received increased attention in recent years. The advent of diffusion-weighted magnetic resonance imaging has permitted the investigation of the white matter microstructure in unprecedented detail. Here, we aimed to study the potential influences of biological sex, gender identity, sex hormones, and sexual orientation on white matter microstructure by investigating transsexuals and healthy controls using diffusion tensor imaging (DTI). Twenty-three female-to-male (FtM) and 21 male-to-female (MtF) transsexuals, as well as 23 female (FC) and 22 male (MC) controls underwent DTI at 3 tesla. Fractional anisotropy, axial, radial, and mean diffusivity were calculated using tract-based spatial statistics (TBSS) and fiber tractography. Results showed widespread significant differences in mean diffusivity between groups in almost all white matter tracts. FCs had highest mean diffusivities, followed by FtM transsexuals with lower values, MtF transsexuals with further reduced values, and MCs with lowest values. Investigating axial and radial diffusivities showed that a transition in axial diffusivity accounted for mean diffusivity results. No significant differences in fractional anisotropy maps were found between groups. Plasma testosterone levels were strongly correlated with mean, axial, and radial diffusivities. However, controlling for individual estradiol, testosterone, or progesterone plasma levels or for subjects’ sexual orientation did not change group differences. Our data harmonize with the hypothesis that fiber tract development is influenced by the hormonal environment during late prenatal and early postnatal brain development. PMID:25392513

  18. 78 FR 58507 - Endangered and Threatened Wildlife and Plants; 90-Day Finding on a Petition To List 10 Sturgeon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-24

    ... distribution patterns, particularly regarding their seasonal migrations; (d) Historical and current population... sturgeon (Acipenser baerii). Endangered Decreasing China; Kazakhstan; Mongolia; Russia. Yangtze sturgeon (Acipenser Critically Endangered.. Decreasing China. dabryanus). Russian sturgeon (Acipenser...

  19. Immunochemical investigation of allergenic residues in experimental and commercially-available wines fined with egg white proteins.

    PubMed

    Uberti, Francesca; Danzi, Roberta; Stockley, Creina; Peñas, Elena; Ballabio, Cinzia; Di Lorenzo, Chiara; Tarantino, Chiara; Restani, Patrizia

    2014-09-15

    Proteinaceous egg whites are widely used as a fining agent during the production of red wines. Residues of egg white in the final wine could present a risk for individuals allergic to eggs. This study investigated the presence of allergenic residues in both red and white wines fined with egg whites. Experimental and commercially available wines fined with egg whites, with or without subsequent bentonite fining, were studied. Unfined wines were used as negative controls. The physicochemical characteristics of each wine were determined to assess their possible role in enhancing or hindering the elimination of allergenic residues from wine. The amount of egg white protein residues was investigated both by a specifically developed/validated ELISA test and by immunoblotting. Both immunochemical tests used the same anti-total egg white protein antibody and were highly sensitive to the allergen. No egg white protein was detected in the wines studied in either immunochemical test, irrespective of the physicochemical characteristics of the wine, the type and dosage of the fining agent and the oenological process used. The risk of adverse reactions in egg-allergic individuals should therefore be considered negligible, but the exemption from labelling should be allowed only when the absence of residues is confirmed by analytical controls.

  20. Immunochemical investigation of allergenic residues in experimental and commercially-available wines fined with egg white proteins.

    PubMed

    Uberti, Francesca; Danzi, Roberta; Stockley, Creina; Peñas, Elena; Ballabio, Cinzia; Di Lorenzo, Chiara; Tarantino, Chiara; Restani, Patrizia

    2014-09-15

    Proteinaceous egg whites are widely used as a fining agent during the production of red wines. Residues of egg white in the final wine could present a risk for individuals allergic to eggs. This study investigated the presence of allergenic residues in both red and white wines fined with egg whites. Experimental and commercially available wines fined with egg whites, with or without subsequent bentonite fining, were studied. Unfined wines were used as negative controls. The physicochemical characteristics of each wine were determined to assess their possible role in enhancing or hindering the elimination of allergenic residues from wine. The amount of egg white protein residues was investigated both by a specifically developed/validated ELISA test and by immunoblotting. Both immunochemical tests used the same anti-total egg white protein antibody and were highly sensitive to the allergen. No egg white protein was detected in the wines studied in either immunochemical test, irrespective of the physicochemical characteristics of the wine, the type and dosage of the fining agent and the oenological process used. The risk of adverse reactions in egg-allergic individuals should therefore be considered negligible, but the exemption from labelling should be allowed only when the absence of residues is confirmed by analytical controls. PMID:24767065

  1. Ontogenetic behavior and migration of Volga River Russian sturgeon, Acipenser gueldenstaedtii, with a note on adaptive significance of body color

    USGS Publications Warehouse

    Kynard, B.; Zhuang, P.; Zhang, L.; Zhang, T.; Zhang, Z.

    2002-01-01

    We conducted laboratory experiments with Volga River Russian sturgeon, Acipenser gueldenstaedtii, to develop a conceptual model of early behavior. We daily observed fish from day-0 (embryos, first life interval after hatching) to day-29 feeding larvae for preference of bright habitat and cover, swimming distance above the bottom, up- and downstream movement, and diel activity. Hatchling embryos initiated a downstream migration, which suggests that predation risk of embryos at spawning sites is high. Migration peaked on days 0-5 and ceased on day 7 (8-day migration). Migrants preferred bright, open habitat and early migrants swam-up far above the bottom (maximum daily median, 140 cm) in a vertical swim tube. Post-migrant embryos did not prefer bright illumination but continued to prefer white substrate, increased use of cover habitat, and swam on the bottom. Larvae initiated feeding on day 10 after 170.6 cumulative temperature degree-days. Larvae did not migrate, weakly preferred bright illumination, preferred white substrate and open habitat, and swam near the bottom (daily median 5-78 cm). The lack of a strong preference by larvae for bright illumination suggests foraging relies more on olfaction than vision for locating prey. A short migration by embryos would disperse wild sturgeon from a spawning area, but larvae did not migrate, so a second later migration by juveniles disperses young sturgeon to the sea (2-step migration). Embryo and larva body color was light tan and tail color was black. The migration, behavior, and light body color of Russian sturgeon embryos was similar to species of Acipenser and Scaphirhynchus in North America and to Acipenser in Asia that migrate after hatching as embryos. The similarity in migration style and body color among species with diverse phylogenies likely reflects convergence for common adaptations across biogeographic regions. ?? 2002 Kluwer Academic Publishers.

  2. Application of new phenolic antioxidants for cryopreservation of sturgeon sperm.

    PubMed

    Osipova, V P; Berberova, N T; Gazzaeva, R A; Kudryavtsev, K V

    2016-04-01

    Heterocyclic derivatives of butylated hydroxytoluene (BHT) were studied as cryoprotectants of the basic media for cryopreservation of the Russian sturgeon sperm. Rates of lipid peroxidation of sturgeon sperm before and after cryopreservation were reduced in the presence of the studied compounds, exceeding the effects of BHT and water-soluble analogue of vitamin E, trolox. The most efficient antioxidant has the effective concentration of 0.1 mM. Novel antioxidant agents as cryomedium supplements not only reduced the level of lipid peroxidation, but also enhanced the translational motility of the sperm of the Russian sturgeon after defrosting.

  3. Factors Affecting the Reproduction, Recruitment, Habitat, and Population Dynamics of Pallid Sturgeon and Shovelnose Sturgeon in the Missouri River

    USGS Publications Warehouse

    Korschgen, Carl E.

    2007-01-01

    For more than a hundred years, human activities have modified the natural forces that control the Missouri River and its native fish fauna. While the ecological effects of regulation and channel engineering are understood in general, the current understanding is not sufficient to guide river restoration and management. The U.S. Geological Survey (USGS) is in the third year of a multiagency research effort to determine the ecological requirements for reproduction and survival of the endangered pallid sturgeon (Scaphirhynchus albus) and shovelnose sturgeon (Scaphirhynchus platorhynchus) in the Missouri River. The multidisciplinary research strategy includes components of behavior, physiology, habitat use, habitat availability, and population modeling of all life stages. Shovelnose sturgeon are used to design the strategy because they are closely related to the pallid sturgeon and are often used as a surrogate species to develop new research tools or to examine the effects of management actions or environmental variables on sturgeon biology and habitat use. During fiscal years 2005 and 2006, the U.S. Army Corps of Engineers (USACE) provided funds to USGS for tasks associated with the Comprehensive Sturgeon Research Program (CSRP) and for tasks associated with evaluation of the Sturgeon Response to Flow Modifications (SRFM). Because work activities of CSRP and SRFM are so integrated, we are providing information on activities that have been consolidated at the task level. These task activities represent chapters in this report.

  4. Gender identification of shovelnose sturgeon using ultrasonic and endoscopic imagery and the application of the method to the pallid sturgeon

    USGS Publications Warehouse

    Wildhaber, M.L.; Papoulias, D.M.; DeLonay, A.J.; Tillitt, D.E.; Bryan, J.L.; Annis, M.L.; Allert, J.A.

    2005-01-01

    Monthly sampling of shovelnose sturgeon Scaphirhynchus platorynchus, a biological surrogate for the endangered pallid sturgeon Scaphirhynchus albus, was conducted to develop a multiseasonal profile of reproductive stages. Data collected included histological characteristics of gonads from wild caught fish and laboratory and field ultrasonic and endoscopic images. These data were used to compare effectiveness of ultrasonic and endoscopic techniques at identifying gender of adult shovelnose sturgeon at different reproductive stages. The least invasive method (i.e. ultrasound) was least effective while the most invasive (i.e. endoscope through an abdominal incision) was the most effective at identifying shovelnose sturgeon gender. In most cases, success rate for identifying males was greater than females, with success at identifying both genders greater in more advanced reproductive stages. Concomitantly, for most months average reproductive stage was more advanced for males than females. April and May were the months with the most advanced reproductive stage, and were the months when ultrasound was most effective. Methods were also applied in the Upper Missouri River to validate their use on pallid sturgeon Scaphirhynchus albus. Ultrasound was successful at identifying pallid sturgeon gender, however, endoscopic examination through the urogenital duct was only successful at identifying pallid sturgeon gender when the urogenital duct was not opaque. ?? 2005 The Fisheries Society of the British Isles.

  5. Physical, chemical, and biological characteristics of Sturgeon Lake, Goodhue County, Minnesota, 2003-04

    USGS Publications Warehouse

    Lee, Kathy E.; Sanocki, Christopher A.; Montz, Gary R.

    2005-01-01

    The U.S. Geological Survey, in cooperation with the Prairie Island Indian Community and the Minnesota Department of Natural Resources, conducted a study of Sturgeon Lake (a backwater lake in Navigation Pool 3 of the Mississippi River) during 2003-04 to describe the physical, chemical, and biological characteristics of the lake. Riparian and shoreline areas surrounding Sturgeon Lake consist primarily of deciduous tree and shrub cover with minimal amounts of commercial or residential land use. Woody debris and aquatic vegetation are the major types of physical habitat suitable for fish and invertebrates. Among 10 bottom-sediment sampling sites, 24 organic wastewater compounds, 1 organochlorine pesticide metabolite (p,p’DDE), and total polychlorinated biphenyls (PCBs) were detected in the bottom sediments of Sturgeon Lake. The most prevalent class of compounds detected were polyaromatic hydrocarbons. Other classes of compounds detected include sterols, disinfectants, plastic components, alkylphenols, and fragrances. Three compounds detected (bisphenol A, benzo[a]pyrene, and triclosan) are considered endocrine disrupting compounds. Twenty-one and 49 invertebrate taxa were identified from 10 bottom-sediment and 6 woody-debris/vegetation samples, respectively. Most of the taxa were Diptera in the family Chironomidae. The most common invertebrate in terms of density in bottom-sediment samples was the burrowing mayfly (Hexagenia sp.). Trichoptera in the families Hydropsychidae or Polycentropodidae were common in most of the woody-debris samples. The presence of the Hexagenia larvae in samples indicates that the bottom sediments are stable and that dissolved oxygen concentrations in the lake do not drop to acute or sub-lethal anoxic conditions. Backwater lakes such as Sturgeon Lake are important areas of habitat for aquatic organisms along the Mississippi River, and this report provides baseline physical, chemical, and biological information that resource managers can

  6. Histopathological effects of silver and copper nanoparticles on the epidermis, gills, and liver of Siberian sturgeon.

    PubMed

    Ostaszewska, Teresa; Chojnacki, Maciej; Kamaszewski, Maciej; Sawosz-Chwalibóg, Ewa

    2016-01-01

    The influence of nanoparticles (NPs) on aquatic environments is still poorly documented. The aim of the study was to determine the effects of silver (AgNPs) and copper (CuNPs) nanoparticles on larval Siberian sturgeon (Acipenser baerii) after 21 days of exposure. Acute toxicity of AgNPs on Siberian sturgeon was investigated in a 96-h static renewal study and compared with the toxicity of CuNPs. The AgNPs and CuNPs 96 h mean lethal concentrations (96 h LC50) were 15.03 ± 2.91 and 1.41 ± 0.24 mg L(-1), respectively. Toxicity tests were done in triplicates for each concentration of AgNPs 0.1, 0.5, 1.5 mg L(-1) and CuNPs 0.01, 0.05, 0.15 mg L(-1). The control group was exposed in freshwater. The results indicate that AgNPs and CuNPs exposure negatively influenced survival; body length and mass; and morphology and physiology of the epidermis, gills, and liver of Siberian sturgeon larvae. Fish exposed to AgNPs and CuNPs showed similar pathological changes: irregular structure and pyknotic nuclei of epidermis, aplasia and/or fusion of lamellae, telangiectasis, epithelial necrosis and lifting of the gills, dilation of sinusoidal space, overfilled blood vessels, and pyknotic nuclei of the liver. Fish exposed to CuNPs only demonstrated hyaline degeneration in the gills epithelium and liver. The study shows that CuNPs were more toxic to Siberian sturgeon larvae than AgNPs.

  7. Efficacy of iodine for disinfection of Lake Sturgeon eggs from the St. Lawrence River, New York

    USGS Publications Warehouse

    Chalupnicki, Marc A.; Dittman, Dawn E.; Starliper, Clifford E.; Iwanowicz, Deborah

    2014-01-01

    Optimal fish husbandry to reduce the risk of disease is particularly important when using wild fish as the source for gametes. The propagation and reestablishment of Lake Sturgeon Acipenser fulvescens in New York waters to become a viable self-sustaining population is considered a high priority by managers. While standard hatchery egg disinfection practices have been used to prevent the transmission of diseases, data on the bacterial loads present on egg surfaces following iodine disinfection is lacking. Our study investigated the bacteria present on the outer surface of Lake Sturgeon eggs and the effectiveness of an iodine disinfection treatment in eliminating bacteria that could pose a threat to egg survival and cause hatchery disease outbreaks. During the springs of 2011–2013, 12 to 41 different species of bacteria were recovered from the outer egg surfaces prior to an iodine treatment; Aeromonas, Pseudomonas, Shewanella, and Chryseobacterium were the most common genera identified. Cohort eggs treated using the standard protocol of a single treatment of 50 mg/L iodine for 30 min resulted in an average of 57.8% reduction in bacterial CFU/g. While this is a significant reduction, bacteria were not completely eliminated and hatchery managers should be aware that pathogens could remain on Lake Sturgeon eggs following the standard iodine disinfection treatment.

  8. Turnover of hydrogen isotopes in lake sturgeon blood: implications for tracking movements of wild populations.

    PubMed

    Kreitals, Natasha M; Hobson, Keith A; Hoemsen, Brittney M; Crane, Adam L; Wishingrad, Van; Sloychuk, Janelle; Pollock, Michael S; Chivers, Douglas P; Phillips, Iain D

    2016-12-01

    Naturally occurring deuterium ((2)H) in biota can be used to trace movement, migration and geographic origin of a range of organisms. However, to evaluate movements of animals using δ(2)H measurements of tissues, it is necessary to establish the turnover time of (2)H in the tissues and the extent of isotopic discrimination from different environmental (2)H sources to those tissues. We investigated the turnover of (2)H in lake sturgeon (Acipenser fulvescens) blood by manipulating both environmental water δ(2)H and diet δ(2)H over a four-month period. The half-life of deuterium in lake sturgeon blood was 37.9 days after an increase in the environmental water δ(2)H of +714 ‰. However, no clear turnover in blood (2)H occurred over the same period in a separate trial following a change of -63.8 ‰ or +94.2 ‰ in diet. These findings suggest that environmental water (2)H exchanges much faster with blood than diets and that blood δ(2)H values can be used to trace movements of sturgeon and other fish moving among isotopically distinct waters.

  9. [Meiotic gynogenesis in the stellate, Russian sturgeon and sterlet].

    PubMed

    Rekubratskiĭ, A V; Grunina, A S; Barmintsev, V A; Golovanova, T S; Chudinov, O S; Abramova, A B; Panchenko, N S; Kupchenko, S A

    2003-01-01

    Diploid gynogenetic progenies were obtained in the stellate sturgeon Acipenser stellatus, Russian sturgeon A. gueldenstaedtii, and sterlet A. ruthenus by means of insemination of the eggs with UV-irradiated spermatozoa and suppression of the second meiotic division by heat shock. The gynogenetic nature of experimental fish was confirmed by RAPD-PCR analysis of DNA. Effective photoreactivation of UV-induced lesions of spermatozoa was shown in the case of illumination of the fertilized eggs with visible light. This phenomenon should be taken into account when determining the doses of irradiation that allow inactivation of the male chromosomes and incubating gynogenetic embryos. Gynogenetic stellate and Russian sturgeons are viable and can be reared in order to study the mechanism of sex determination in sturgeons. PMID:12722590

  10. Depleted uranium investigation at missile impact sites in White Sands Missile Range

    SciTech Connect

    Van Etten, D.M.; Purtymun, W.D.

    1994-01-01

    An investigation for residual depleted uranium was conducted at Pershing missile impact sites on the White Sands Missile Range. Subsurface core soil samples were taken at Chess, Salt Target, and Mine Impact Sites. A sampling pump was installed in a monitoring well at Site 65 where a Pershing earth penetrator was not recovered. Pumping tests and water samples were taken at this site. Chess Site, located in a gypsum flat, was the only location showing elevated levels of depleted uranium in the subsurface soil or perched groundwater. Small fragments can still be found on the surface of the impact sites. The seasonal flooding and near surface water has aided in the movement of surface fragments.

  11. Verifying success of artificial spawning reefs in the St. Clair-Detroit River System for lake sturgeon (Acipenser fulvescens Rafinesque, 1817)

    USGS Publications Warehouse

    Bouckaert, Emliy K.; Auer, Nancy A.; Roseman, Edward F.; James Boase,

    2014-01-01

    Lake sturgeon (Acipenser fulvescens) were historically abundant in the St. Clair – Detroit River System (SCDRS), a 160 km river/channel network. In the SCDRS, lake sturgeon populations have been negatively affected by the loss/degradation of natural spawning habitat. To address habitat loss for lake sturgeon and other species, efforts are underway to restore spawning substrate by constructing artificial reefs. The main objective of this study was to conduct post-construction monitoring of lake sturgeon egg deposition and larval emergence near two of these artificial reefs: Fighting Island Reef (FIR) in the Detroit River, and Middle Channel Reef in the St. Clair River. An additional site in the St. Clair River where lake sturgeon spawn on a coal clinker bed was also investigated. From 2010 to 2012, viable eggs and larvae were collected from all of these reefs, indicating that conditions are suitable for egg deposition, incubation, and larval emergence. In the St. Clair River, the results indicate the likelihood of other spawning sites upstream of these artificial reef sites.

  12. Optimal design of artificial reefs for sturgeon

    NASA Astrophysics Data System (ADS)

    Yarbrough, Cody; Cotel, Aline; Kleinheksel, Abby

    2015-11-01

    The Detroit River, part of a busy corridor between Lakes Huron and Erie, was extensively modified to create deep shipping channels, resulting in a loss of spawning habitat for lake sturgeon and other native fish (Caswell et al. 2004, Bennion and Manny 2011). Under the U.S.- Canada Great Lakes Water Quality Agreement, there are remediation plans to construct fish spawning reefs to help with historic habitat losses and degraded fish populations, specifically sturgeon. To determine optimal reef design, experimental work has been undertaken. Different sizes and shapes of reefs are tested for a given set of physical conditions, such as flow depth and flow velocity, matching the relevant dimensionless parameters dominating the flow physics. The physical conditions are matched with the natural conditions encountered in the Detroit River. Using Particle Image Velocimetry, Acoustic Doppler Velocimetry and dye studies, flow structures, vorticity and velocity gradients at selected locations have been identified and quantified to allow comparison with field observations and numerical model results. Preliminary results are helping identify the design features to be implemented in the next phase of reef construction. Sponsored by NOAA.

  13. Sturgeon Research Update: Confirmed Pallid Sturgeon Spawning in the Missouri River in 2007

    USGS Publications Warehouse

    Mac, Michael; Mestl, Gerald

    2007-01-01

    The U.S. Geological Survey (USGS) in partnership with the Nebraska Game and Parks Commission (NGPC) and the U.S. Army Corps of Engineers have confirmed spawning of two female pallid sturgeon in the upstream reaches of the lower Missouri River in May 2007. Combined with supporting research in reproductive physiology, identification of spawning habitat, and early life history this result provides new understanding of environmental factors (for example, photoperiod, temperature, water quality, and flow regime) that might affect reproduction of this endangered species. The purpose of this fact sheet is to provide stakeholders, scientists, and managers with some of the preliminary results from the 2007 field assessment of sturgeon reproduction in the lower Missouri River.

  14. Remote-sensing of Riverine Environments Utilized by Spawning Pallid Sturgeon Using a Suite of Hydroacoustic Tools and High-resolution DEMs

    NASA Astrophysics Data System (ADS)

    Elliott, C. M.; Jacobson, R. B.; DeLonay, A. J.; Braaten, P. J.

    2013-12-01

    The pallid sturgeon (Scaphirynchus albus) inhabits sandy-bedded rivers in the Mississippi River basin including the Missouri and Lower Yellowstone Rivers and has experienced decline generally associated with the fragmentation and alteration of these river systems. Knowledge gaps in the life history of the pallid sturgeon include lack of an understanding of conditions needed for successful reproduction and recruitment. We employed hydroacoustic tools to investigate habitats utilized by spawning pallid sturgeon in the Missouri River in Missouri, Kansas, Iowa, and Nebraska, and the Yellowstone River in Montana and North Dakota USA from 2008-2013. Reproductive pallid sturgeon were tracked to suspected spawning locations by field crews using either acoustic or radio telemetry, a custom mobile mapping application, and differential global positioning systems (DGPS). Female pallid sturgeon were recaptured soon after spawning events to validate that eggs had been released. Habitats were mapped at presumed spawning and embryo incubation sites using a multibeam echosounder system (MBES), sidescan sonar, acoustic Doppler current profiler, an acoustic camera and either a real-time kinematic global positioning system (RTK GPS) or DGPS. High-resolution DEM's and velocimetric maps were gridded from at a variety of scales from 0.10 to 5 meters for characterization and visualization at spawning and presumed embryo incubation sites. Pallid sturgeon spawning sites on the Missouri River are deep (6-8 meters) and have high current velocities (>1.5 meters per second). These sites are also characterized by high turbidity and high rates of bedload sediment transport in the form of migrating sand dunes. Spawning on the channelized Lower Missouri River occurs on or adjacent to coarse angular bank revetment or bedrock. Collecting biophysical information in these environmental conditions is challenging, and there is a need to characterize the substrate and substrate condition at a scale

  15. Conservation, sex-biased expression and functional annotation of microRNAs in the gonad of Amur sturgeon (Acipenser schrenckii).

    PubMed

    Zhang, Xiujuan; Yuan, Lihong; Li, Linmiao; Jiang, Haiying; Chen, Jinping

    2016-06-01

    MicroRNAs (miRNAs) are involved in post-transcriptional gene regulation and have crucial roles in regulating the expression of gametogenesis-related genes in animals. However, the mechanism of sex determination and differentiation in the sturgeon has remained unclear. Identifying miRNAs and characterizing sex-biased miRNA expression is therefore critical for understanding the role of miRNAs during sexual differentiation in sturgeon. In this study, five different tissues from sturgeon before sex differentiation and the gonads were used for miRNA expression profiling. We screened 1037 miRNAs in miRBase 20.0 and an additional 103 sturgeon miRNAs using microarray and real-time PCR. We found that the sequences of 477 miRNAs out of a total of 1140 miRNAs were highly conserved (100%) among different fish species. From a total of 663 non-redundant miRNA probes, 481 miRNAs were detected in the gonads of both sexes. Of the 148 miRNAs that were identified to have sex-biased expression patterns between the testis and the ovary (P<0.01), 21 miRNAs (14.19%) were relatively highly expressed in the testis or the ovary with fold-changes >2. The microarray expression patterns of 13 randomly selected sex-biased miRNAs were validated using real-time PCR. Target gene prediction revealed a significant enrichment of functional groups (88 GO terms) and 18 KEGG pathways (P<0.05) and suggested that there are interactions between sex-biased miRNAs and 25 putative gametogenesis-related targets. Therefore, our miRNA expression analysis in juvenile A. schrenckii establishes a foundation for understanding and further investigating the role of miRNAs in sturgeon sex differentiation. PMID:27089517

  16. Conservation, sex-biased expression and functional annotation of microRNAs in the gonad of Amur sturgeon (Acipenser schrenckii).

    PubMed

    Zhang, Xiujuan; Yuan, Lihong; Li, Linmiao; Jiang, Haiying; Chen, Jinping

    2016-06-01

    MicroRNAs (miRNAs) are involved in post-transcriptional gene regulation and have crucial roles in regulating the expression of gametogenesis-related genes in animals. However, the mechanism of sex determination and differentiation in the sturgeon has remained unclear. Identifying miRNAs and characterizing sex-biased miRNA expression is therefore critical for understanding the role of miRNAs during sexual differentiation in sturgeon. In this study, five different tissues from sturgeon before sex differentiation and the gonads were used for miRNA expression profiling. We screened 1037 miRNAs in miRBase 20.0 and an additional 103 sturgeon miRNAs using microarray and real-time PCR. We found that the sequences of 477 miRNAs out of a total of 1140 miRNAs were highly conserved (100%) among different fish species. From a total of 663 non-redundant miRNA probes, 481 miRNAs were detected in the gonads of both sexes. Of the 148 miRNAs that were identified to have sex-biased expression patterns between the testis and the ovary (P<0.01), 21 miRNAs (14.19%) were relatively highly expressed in the testis or the ovary with fold-changes >2. The microarray expression patterns of 13 randomly selected sex-biased miRNAs were validated using real-time PCR. Target gene prediction revealed a significant enrichment of functional groups (88 GO terms) and 18 KEGG pathways (P<0.05) and suggested that there are interactions between sex-biased miRNAs and 25 putative gametogenesis-related targets. Therefore, our miRNA expression analysis in juvenile A. schrenckii establishes a foundation for understanding and further investigating the role of miRNAs in sturgeon sex differentiation.

  17. Reconnecting fragmented sturgeon populations in North American rivers

    USGS Publications Warehouse

    Jager, Henriette; Parsley, Michael J.; Cech, Joseph J. Jr.; McLaughlin, R.L.; Forsythe, Patrick S.; Elliott, Robert S.

    2016-01-01

    The majority of large North American rivers are fragmented by dams that interrupt migrations of wide-ranging fishes like sturgeons. Reconnecting habitat is viewed as an important means of protecting sturgeon species in U.S. rivers because these species have lost between 5% and 60% of their historical ranges. Unfortunately, facilities designed to pass other fishes have rarely worked well for sturgeons. The most successful passage facilities were sized appropriately for sturgeons and accommodated bottom-oriented species. For upstream passage, facilities with large entrances, full-depth guidance systems, large lifts, or wide fishways without obstructions or tight turns worked well. However, facilitating upstream migration is only half the battle. Broader recovery for linked sturgeon populations requires safe “round-trip” passage involving multiple dams. The most successful downstream passage facilities included nature-like fishways, large canal bypasses, and bottom-draw sluice gates. We outline an adaptive approach to implementing passage that begins with temporary programs and structures and monitors success both at the scale of individual fish at individual dams and the scale of metapopulations in a river basin. The challenge will be to learn from past efforts and reconnect North American sturgeon populations in a way that promotes range expansion and facilitates population recovery.

  18. Detection of Adult Green Sturgeon Using Environmental DNA Analysis

    PubMed Central

    Bergman, Paul S.; Schumer, Gregg; Blankenship, Scott; Campbell, Elizabeth

    2016-01-01

    Environmental DNA (eDNA) is an emerging sampling method that has been used successfully for detection of rare aquatic species. The Identification of sampling tools that are less stressful for target organisms has become increasingly important for rare and endangered species. A decline in abundance of the Southern Distinct Population Segment (DPS) of North American Green Sturgeon located in California’s Central Valley has led to its listing as Threatened under the Federal Endangered Species Act in 2006. While visual surveys of spawning Green Sturgeon in the Central Valley are effective at monitoring fish densities in concentrated pool habitats, results do not scale well to the watershed level, providing limited spatial and temporal context. Unlike most traditional survey methods, environmental DNA analysis provides a relatively quick, inexpensive tool that could efficiently monitor the presence and distribution of aquatic species. We positively identified Green Sturgeon DNA at two locations of known presence in the Sacramento River, proving that eDNA can be effective for monitoring the presence of adult sturgeon. While further study is needed to understand uncertainties of the sampling method, our study represents the first documented detection of Green Sturgeon eDNA, indicating that eDNA analysis could provide a new tool for monitoring Green Sturgeon distribution in the Central Valley, complimenting traditional on-going survey methods. PMID:27096433

  19. Spawning by lake sturgeon (Acipenser fulvescens) in the Detroit River

    USGS Publications Warehouse

    Caswell, N.M.; Peterson, D.L.; Manny, B.A.; Kennedy, G.W.

    2004-01-01

    Overfishing and habitat destruction in the early 1900s devastated lake sturgeon (Acipenser fulvescens) populations in the Great Lakes. Although a comprehensive restoration strategy for this species was recently drafted by the Michigan Department of Natural Resources, a lack of current data on Great Lakes sturgeon stocks has hindered rehabilitation efforts. Historically, the Detroit River supported one of the largest lake sturgeon populations in the Great Lakes; however, little is known about the current population or its habitat use. The main objective of this study was to determine if lake sturgeon spawns in the Detroit River. As part of a larger study, baited setlines were used to capture lake sturgeon in the Detroit River in the spring and summer of 2000 and 2001. In each year of the study, ultrasonic transmitters were surgically implanted in 10 adult fish to track their movements, evaluate habitat use and identify possible spawning sites. Using telemetry and egg mats to verify spawning activity, one spawning site was located and verified in the Detroit River. Spawning was verified by recovering sturgeon eggs deposited on egg collection mats anchored at the site. Telemetry data suggested that several other possible spawning sites also may exist, however, spawning activity was not verified at these sites.

  20. Detection of Adult Green Sturgeon Using Environmental DNA Analysis.

    PubMed

    Bergman, Paul S; Schumer, Gregg; Blankenship, Scott; Campbell, Elizabeth

    2016-01-01

    Environmental DNA (eDNA) is an emerging sampling method that has been used successfully for detection of rare aquatic species. The Identification of sampling tools that are less stressful for target organisms has become increasingly important for rare and endangered species. A decline in abundance of the Southern Distinct Population Segment (DPS) of North American Green Sturgeon located in California's Central Valley has led to its listing as Threatened under the Federal Endangered Species Act in 2006. While visual surveys of spawning Green Sturgeon in the Central Valley are effective at monitoring fish densities in concentrated pool habitats, results do not scale well to the watershed level, providing limited spatial and temporal context. Unlike most traditional survey methods, environmental DNA analysis provides a relatively quick, inexpensive tool that could efficiently monitor the presence and distribution of aquatic species. We positively identified Green Sturgeon DNA at two locations of known presence in the Sacramento River, proving that eDNA can be effective for monitoring the presence of adult sturgeon. While further study is needed to understand uncertainties of the sampling method, our study represents the first documented detection of Green Sturgeon eDNA, indicating that eDNA analysis could provide a new tool for monitoring Green Sturgeon distribution in the Central Valley, complimenting traditional on-going survey methods. PMID:27096433

  1. Detection of Adult Green Sturgeon Using Environmental DNA Analysis.

    PubMed

    Bergman, Paul S; Schumer, Gregg; Blankenship, Scott; Campbell, Elizabeth

    2016-01-01

    Environmental DNA (eDNA) is an emerging sampling method that has been used successfully for detection of rare aquatic species. The Identification of sampling tools that are less stressful for target organisms has become increasingly important for rare and endangered species. A decline in abundance of the Southern Distinct Population Segment (DPS) of North American Green Sturgeon located in California's Central Valley has led to its listing as Threatened under the Federal Endangered Species Act in 2006. While visual surveys of spawning Green Sturgeon in the Central Valley are effective at monitoring fish densities in concentrated pool habitats, results do not scale well to the watershed level, providing limited spatial and temporal context. Unlike most traditional survey methods, environmental DNA analysis provides a relatively quick, inexpensive tool that could efficiently monitor the presence and distribution of aquatic species. We positively identified Green Sturgeon DNA at two locations of known presence in the Sacramento River, proving that eDNA can be effective for monitoring the presence of adult sturgeon. While further study is needed to understand uncertainties of the sampling method, our study represents the first documented detection of Green Sturgeon eDNA, indicating that eDNA analysis could provide a new tool for monitoring Green Sturgeon distribution in the Central Valley, complimenting traditional on-going survey methods.

  2. Reconnecting fragmented sturgeon populations in North American rivers

    DOE PAGESBeta

    Jager, Yetta; Forsythe, Patrick S.; McLaughlin, Robert L.; Joseph J. Cech, Jr.; Parsley, Michael; Elliott, Robert F.; Pracheil, Brenda M.

    2016-02-24

    The majority of large North American rivers are fragmented by dams that interrupt migrations of wide-ranging fishes like sturgeons. Reconnecting habitat is viewed as an important means of protecting sturgeon species in U.S. rivers because these species have lost between 5% and 60% of their historical ranges. Unfortunately, facilities designed to pass other fishes have rarely worked well for sturgeons. The most successful passage facilities were sized appropriately for sturgeons and accommodated bottom-oriented species. For upstream passage, facilities with large entrances, full-depth guidance systems, large lifts, or wide fishways without obstructions or tight turns worked well. However, facilitating upstream migrationmore » is only half the battle. Broader recovery for linked sturgeon populations requires safe round-trip passage involving multiple dams. The most successful downstream passage facilities included nature-like fishways, large canal bypasses, and bottom-draw sluice gates. We outline an adaptive approach to implementing passage that begins with temporary programs and structures and monitors success both at the scale of individual fish at individual dams and the scale of metapopulations in a river basin. The challenge will be to learn from past efforts and reconnect North American sturgeon populations in a way that promotes range expansion and facilitates population recovery.« less

  3. The effects of temperature and body size on immunological development and responsiveness in juvenile shortnose sturgeon (Acipenser brevirostrum).

    PubMed

    Gradil, Ana M; Wright, Glenda M; Speare, David J; Wadowska, Dorota W; Purcell, Sara; Fast, Mark D

    2014-10-01

    Sturgeon are an important evolutionary taxa of which little is known regarding their responses to environmental factors. Water temperature strongly influences growth in fish; however, its effect on sturgeon immune responses is unknown. The objective of this study was to assess how 2 different temperatures affect immune responses in shortnose sturgeon (Acipenser brevirostrum) relevant immune organs such as the meningeal myeloid tissue, spleen, thymus and skin. These responses were studied in 2 different sizes of same age juvenile sturgeon kept at either 11 °C or 20 °C (4 treatment groups), before and after exposure to an ectoparasitic copepod (Dichelesthium oblongum). Based on a differential cell count, temperature was found to strongly influence immune cell production in the meningeal myeloid tissue, regardless of the fish sizes considered. Morphometric analysis of splenic white pulp showed a transient response to temperature. There were no differences between the groups in the morphometric analysis of thymus size. Splenic IRF-1 and IRF-2 had similar expression profiles, significantly higher in fish kept at 20 °C for the first 6 weeks of the study but not by 14 weeks. In the skin, IRF-1 was significantly higher in the fish kept at 11 °C over the first 6 weeks of the study. IRF-2 had a similar profile but there were no differences between the groups by the end of the trial. In conclusion, higher water temperatures (up to 20 °C) may have beneficial effects in maximizing growth and improving immunological capacity, regardless of the fish sizes considered in this study.

  4. New disease records for hatchery-reared sturgeon. II. Phaeohyphomycosis due to Veronaea botryosa.

    PubMed

    Steckler, Natalie K; Yanong, Roy P E; Pouder, Deborah B; Nyaoke, Akinyi; Sutton, Deanna A; Lindner, Jonathan R; Wickes, Brian L; Frasca, Salvatore; Wolf, Jeffrey C; Waltzek, Thomas B

    2014-10-16

    A series of fungal cases in hatchery-reared juvenile and young adult Siberian sturgeon Acipenser baerii and white sturgeon A. transmontanus occurred at production facilities in Florida and California, USA, respectively. Affected fish exhibited abnormal orientation and/or buoyancy, emaciation, coelomic distension, exophthalmos, cutaneous erythema, and ulcerative skin and eye lesions. Necropsies revealed haemorrhage throughout the coelom, serosanguinous coelomic effusion and organomegaly with nodular or cystic lesions in multiple organs. Fungal hyphae were observed in 27 fish (24 A. baerii and 3 A. transmontanus) via microscopic examination of tissue wet mounts and on slides prepared from colonies grown on culture media. Histopathological examination of these infected tissues revealed extensive infiltration by melanised fungal hyphae that were recovered in culture. Phenotypic characteristics and sequencing of the fungal isolates with the use of the internal transcribed spacer region and 28S rRNA gene confirmed the aetiological agent as Veronaea botryosa. To our knowledge, this is the first documentation of V. botryosa infection in fish, although melanised fungi of the closely related genus Exophiala are well-known pathogens of freshwater and marine fishes. PMID:25320035

  5. High-throughput SNP-genotyping analysis of the relationships among Ponto-Caspian sturgeon species

    PubMed Central

    Rastorguev, Sergey M; Nedoluzhko, Artem V; Mazur, Alexander M; Gruzdeva, Natalia M; Volkov, Alexander A; Barmintseva, Anna E; Mugue, Nikolai S; Prokhortchouk, Egor B

    2013-01-01

    Abstract Legally certified sturgeon fisheries require population protection and conservation methods, including DNA tests to identify the source of valuable sturgeon roe. However, the available genetic data are insufficient to distinguish between different sturgeon populations, and are even unable to distinguish between some species. We performed high-throughput single-nucleotide polymorphism (SNP)-genotyping analysis on different populations of Russian (Acipenser gueldenstaedtii), Persian (A. persicus), and Siberian (A. baerii) sturgeon species from the Caspian Sea region (Volga and Ural Rivers), the Azov Sea, and two Siberian rivers. We found that Russian sturgeons from the Volga and Ural Rivers were essentially indistinguishable, but they differed from Russian sturgeons in the Azov Sea, and from Persian and Siberian sturgeons. We identified eight SNPs that were sufficient to distinguish these sturgeon populations with 80% confidence, and allowed the development of markers to distinguish sturgeon species. Finally, on the basis of our SNP data, we propose that the A. baerii-like mitochondrial DNA found in some Russian sturgeons from the Caspian Sea arose via an introgression event during the Pleistocene glaciation. In the present study, the high-throughput genotyping analysis of several sturgeon populations was performed. SNP markers for species identification were defined. The possible explanation of the baerii-like mitotype presence in some Russian sturgeons in the Caspian Sea was suggested. PMID:24567827

  6. Distribution of lake sturgeon in New York: 11 years of restoration management

    USGS Publications Warehouse

    Chalupnicki, M.A.; Dittman, D.E.; Carlson, D.M.

    2011-01-01

    Lake sturgeon (Acipenser fulvescens) are native within the Lake Ontario drainage basin and listed as threatened by New York State. In 1995 the New York State Department of Environmental Conservation (NYSDEC) initiated restoration management of lake sturgeon. This management included both protection of extant populations and stocking of uninhabited historic waters with juvenile sturgeon. A list compiled by NYSDEC of observations of lake sturgeon from New York State waters for the period encompassing 1800-2005 was combined with recent observations through 2008 and formatted (Geographic Information System) to allow mapping of sturgeon geographical distribution. Distributions of pre- and post-restoration sturgeon were examined by occurrence and type of observation. Distribution patterns indicated lakes and rivers with current sturgeon presence have increased from five to eight, which was the first-phase goal of the New York Lake Sturgeon Recovery Plan. Lake sturgeon have started to expand into joining water to include the Indian R., Oneida R., Seneca R. and Oswego R. The protected historic populations in the Niagara R., Grasse R., St. Lawrence R., and Lakes Erie and Ontario continue to have low numbers of sturgeon observations. This summary of mapped lake sturgeon distribution information will help in guiding research assessments to waters containing substantial populations. These accessible reaches provide a generous advantage to the released juveniles as they move toward the next goal of restoration, spawning of sturgeon in targeted waters. ?? 2011 American Midland Naturalist.

  7. 77 FR 8801 - Boundary Establishment for Sturgeon National Wild and Scenic River; Hiawatha National Forest...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-15

    ...; ] DEPARTMENT OF AGRICULTURE Forest Service Boundary Establishment for Sturgeon National Wild and Scenic River..., Washington Office, is transmitting the final boundary of the Sturgeon National Wild and Scenic River to... 157. SUPPLEMENTARY INFORMATION: The Sturgeon Wild and Scenic River boundary is available for review...

  8. 77 FR 51767 - Endangered and Threatened Wildlife; 90-Day Finding on a Petition To List Five Species of Sturgeon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-27

    ... spawn in freshwater habitats while spending part of their life cycle in marine or estuarine waters (i.e...--Persian sturgeon; A. stellatus--stellate sturgeon/star sturgeon; A. baerii--Siberian sturgeon; A... species under the ESA (``DPS Policy''; 61 FR 4722; February 7, 1996). A species, subspecies, or DPS...

  9. Complete mitochondrial genome sequences of Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus, Gulf sturgeon, A. o. desotoi and European sturgeon A. sturio (Acipenseriformes: Acipenseridae) obtained through next generation sequencing.

    PubMed

    Popović, Danijela; Baca, Mateusz; Panagiotopoulou, Hanna

    2016-07-01

    Complete mitochondrial genome sequences of European sturgeon and two subspecies of the North American, Atlantic and Gulf sturgeons were determined using MiSeq Illumina technology. All three genomes show typical vertebrate organization. They possess 22 tRNA genes, 13 protein-coding genes, 2 rRNA (ribosomal RNA) genes and a non-coding control region. Excluding ND6, all protein-coding genes are on the heavy strand. The whole mitogenome sequences have been deposited in GenBank under accession numbers KP997216-KP997218.

  10. Modeling Climate Change and Sturgeon Populations in the Missouri River

    USGS Publications Warehouse

    Wildhaber, Mark L.

    2010-01-01

    The U.S. Geological Survey (USGS) Columbia Environmental Research Center (CERC), in collaboration with researchers from the University of Missouri and Iowa State University, is conducting research to address effects of climate change on sturgeon populations (Scaphirhynchus spp.) in the Missouri River. The CERC is conducting laboratory, field, and modeling research to identify causative factors for the responses of fish populations to natural and human-induced environmental changes and using this information to understand sensitivity of sturgeon populations to potential climate change in the Missouri River drainage basin. Sturgeon response information is being used to parameterize models predicting future population trends. These models will provide a set of tools for natural resource managers to assess management strategies in the context of global climate change. This research complements and builds on the ongoing Comprehensive Sturgeon Research Program (CSRP) at the CERC. The CSRP is designed to provide information critical to restoration of the Missouri River ecosystem and the endangered pallid sturgeon (S. albus). Current research is being funded by USGS through the National Climate Change Wildlife Science Center (NCCWSC) and the Science Support Partnership (SSP) Program that is held by the USGS and the U.S. Fish and Wildlife Service. The national mission of the NCCWSC is to improve the capacity of fish and wildlife agencies to respond to climate change and to address high-priority climate change effects on fish and wildlife. Within the national context, the NCCWSC research on the Missouri River focuses on temporal and spatial downscaling and associated uncertainty in modeling climate change effects on sturgeon species in the Missouri River. The SSP research focuses on improving survival and population estimates for pallid sturgeon population models.

  11. Investigating the Microstructural Correlation of White Matter in Autism Spectrum Disorder.

    PubMed

    Dean, Douglas C; Travers, Brittany G; Adluru, Nagesh; Tromp, Do P M; Destiche, Daniel J; Samsin, Danica; Prigge, Molly B; Zielinski, Brandon A; Fletcher, P Thomas; Anderson, Jeffrey S; Froehlich, Alyson L; Bigler, Erin D; Lange, Nicholas; Lainhart, Janet E; Alexander, Andrew L

    2016-06-01

    White matter microstructure forms a complex and dynamical system that is critical for efficient and synchronized brain function. Neuroimaging findings in children with autism spectrum disorder (ASD) suggest this condition is associated with altered white matter microstructure, which may lead to atypical macroscale brain connectivity. In this study, we used diffusion tensor imaging measures to examine the extent that white matter tracts are interrelated within ASD and typical development. We assessed the strength of inter-regional white matter correlations between typically developing and ASD diagnosed individuals. Using hierarchical clustering analysis, clustering patterns of the pairwise white matter correlations were constructed and revealed to be different between the two groups. Additionally, we explored the use of graph theory analysis to examine the characteristics of the patterns formed by inter-regional white matter correlations and compared these properties between ASD and typical development. We demonstrate that the ASD sample has significantly less coherence in white matter microstructure across the brain compared to that in the typical development sample. The ASD group also presented altered topological characteristics, which may implicate less efficient brain networking in ASD. These findings highlight the potential of graph theory based network characteristics to describe the underlying networks as measured by diffusion magnetic resonance imaging and furthermore indicates that ASD may be associated with altered brain network characteristics. Our findings are consistent with those of a growing number of studies and hypotheses that have suggested disrupted brain connectivity in ASD.

  12. A Whole-Brain Investigation of White Matter Microstructure in Adolescents with Conduct Disorder

    PubMed Central

    Sarkar, Sagari; Dell’Acqua, Flavio; Froudist Walsh, Seán; Blackwood, Nigel; Scott, Stephen; Craig, Michael C.

    2016-01-01

    Background The biological basis of severe antisocial behaviour in adolescents is poorly understood. We recently reported that adolescents with conduct disorder (CD) have significantly increased fractional anisotropy (FA) of the uncinate fasciculus (a white matter (WM) tract that connects the amygdala to the frontal lobe) compared to their non-CD peers. However, the extent of WM abnormality in other brain regions is currently unclear. Methods We used tract-based spatial statistics to investigate whole brain WM microstructural organisation in 27 adolescent males with CD, and 21 non-CD controls. We also examined relationships between FA and behavioural measures. Groups did not differ significantly in age, ethnicity, or substance use history. Results The CD group, compared to controls, had clusters of significantly greater FA in 7 brain regions corresponding to: 1) the bilateral inferior and superior cerebellar peduncles, corticopontocerebellar tract, posterior limb of internal capsule, and corticospinal tract; 2) right superior longitudinal fasciculus; and 3) left cerebellar WM. Severity of antisocial behavior and callous-unemotional symptoms were significantly correlated with FA in several of these regions across the total sample, but not in the CD or control groups alone. Conclusions Adolescents with CD have significantly greater FA than controls in WM regions corresponding predominantly to the fronto-cerebellar circuit. There is preliminary evidence that variation in WM microstructure may be dimensionally related to behaviour problems in youngsters. These findings are consistent with the hypothesis that antisocial behaviour in some young people is associated with abnormalities in WM ‘connectivity’. PMID:27271503

  13. Methods for Predicting Potential Impacts of Pile-Driving Noise on Endangered Sturgeon During Bridge Construction.

    PubMed

    Krebs, Justin; Jacobs, Fred; Conway, Robert; Popper, Arthur N; Moese, Mark; Rollino, John; Racca, Roberto; Martin, Bruce; MacGillivray, Alexander

    2016-01-01

    The potential impacts of pile-driving noise on Hudson River sturgeon during construction of the New NY Bridge were predicted. Abundance data for shortnose and Atlantic sturgeon derived from fisheries sampling were combined with data about the spatial extent of pile-driving noise. This approach was used to calculate the number of sturgeon that could occur within sound level isopleths exceeding peak and cumulative noise criteria used by the National Marine Fisheries Service to determine the incidental take of sturgeon. The number of sturgeon subject to the potential onset of physiological effects during pile driving was predicted to be 35-41 fish for each species.

  14. Sturgeon conservation genomics: SNP discovery and validation using RAD sequencing.

    PubMed

    Ogden, R; Gharbi, K; Mugue, N; Martinsohn, J; Senn, H; Davey, J W; Pourkazemi, M; McEwing, R; Eland, C; Vidotto, M; Sergeev, A; Congiu, L

    2013-06-01

    Caviar-producing sturgeons belonging to the genus Acipenser are considered to be one of the most endangered species groups in the world. Continued overfishing in spite of increasing legislation, zero catch quotas and extensive aquaculture production have led to the collapse of wild stocks across Europe and Asia. The evolutionary relationships among Adriatic, Russian, Persian and Siberian sturgeons are complex because of past introgression events and remain poorly understood. Conservation management, traceability and enforcement suffer a lack of appropriate DNA markers for the genetic identification of sturgeon at the species, population and individual level. This study employed RAD sequencing to discover and characterize single nucleotide polymorphism (SNP) DNA markers for use in sturgeon conservation in these four tetraploid species over three biological levels, using a single sequencing lane. Four population meta-samples and eight individual samples from one family were barcoded separately before sequencing. Analysis of 14.4 Gb of paired-end RAD data focused on the identification of SNPs in the paired-end contig, with subsequent in silico and empirical validation of candidate markers. Thousands of putatively informative markers were identified including, for the first time, SNPs that show population-wide differentiation between Russian and Persian sturgeons, representing an important advance in our ability to manage these cryptic species. The results highlight the challenges of genotyping-by-sequencing in polyploid taxa, while establishing the potential genetic resources for developing a new range of caviar traceability and enforcement tools. PMID:23473098

  15. The Origin And Migration Of Primordial Germ Cells In Sturgeons

    PubMed Central

    Saito, Taiju; Pšenička, Martin; Goto, Rie; Adachi, Shinji; Inoue, Kunio; Arai, Katsutoshi; Yamaha, Etsuro

    2014-01-01

    Primordial germ cells (PGCs) arise elsewhere in the embryo and migrate into developing gonadal ridges during embryonic development. In several model animals, formation and migration patterns of PGCs have been studied, and it is known that these patterns vary. Sturgeons (genus Acipenser) have great potential for comparative and evolutionary studies of development. Sturgeons belong to the super class Actinoptergii, and their developmental pattern is similar to that of amphibians, although their phylogenetic position is an out-group to teleost fishes. Here, we reveal an injection technique for sturgeon eggs allowing visualization of germplasm and PGCs. Using this technique, we demonstrate that the PGCs are generated at the vegetal pole of the egg and they migrate on the yolky cell mass toward the gonadal ridge. We also provide evidence showing that PGCs are specified by inheritance of maternally supplied germplasm. Furthermore, we demonstrate that the migratory mechanism is well-conserved between sturgeon and other remotely related teleosts, such as goldfish, by a single PGCs transplantation (SPT) assay. The mode of PGCs specification in sturgeon is similar to that of anurans, but the migration pattern resembles that of teleosts. PMID:24505272

  16. Sturgeon conservation genomics: SNP discovery and validation using RAD sequencing.

    PubMed

    Ogden, R; Gharbi, K; Mugue, N; Martinsohn, J; Senn, H; Davey, J W; Pourkazemi, M; McEwing, R; Eland, C; Vidotto, M; Sergeev, A; Congiu, L

    2013-06-01

    Caviar-producing sturgeons belonging to the genus Acipenser are considered to be one of the most endangered species groups in the world. Continued overfishing in spite of increasing legislation, zero catch quotas and extensive aquaculture production have led to the collapse of wild stocks across Europe and Asia. The evolutionary relationships among Adriatic, Russian, Persian and Siberian sturgeons are complex because of past introgression events and remain poorly understood. Conservation management, traceability and enforcement suffer a lack of appropriate DNA markers for the genetic identification of sturgeon at the species, population and individual level. This study employed RAD sequencing to discover and characterize single nucleotide polymorphism (SNP) DNA markers for use in sturgeon conservation in these four tetraploid species over three biological levels, using a single sequencing lane. Four population meta-samples and eight individual samples from one family were barcoded separately before sequencing. Analysis of 14.4 Gb of paired-end RAD data focused on the identification of SNPs in the paired-end contig, with subsequent in silico and empirical validation of candidate markers. Thousands of putatively informative markers were identified including, for the first time, SNPs that show population-wide differentiation between Russian and Persian sturgeons, representing an important advance in our ability to manage these cryptic species. The results highlight the challenges of genotyping-by-sequencing in polyploid taxa, while establishing the potential genetic resources for developing a new range of caviar traceability and enforcement tools.

  17. Survival of shovelnose sturgeon after abdominally invasive endoscopic evaluation

    USGS Publications Warehouse

    Trested, D.G.; Goforth, Reuben R.; Kirk, J.P.; Isely, J.J.

    2010-01-01

    The development of effective and minimally invasive techniques to determine gender and gonad developmental stage is particularly important in performing accurate fisheries assessments for use in conservation and restoration. The initial and latent survival of shovelnose sturgeon Scaphirhynchus platorynchus was assessed after exposure to a modified endoscopic technique designed to collect that biological information. Rather than inserting the endoscope through the urogenital canal or directly into the body cavity, we inserted a threaded trocar through a ventral incision and used a low-pressure air supply attached to the trocar to gently insufflate the body cavity. The initial survival of both experimental and control shovelnose sturgeon was 100%. Latent survival was 100% and 90% for the experimental and control fish, respectively. Our study suggests that incision endoscopy coupled with insufflation of the body cavity through the use of a trocar and an air supply is a safe and effective way to determine gender and examine the gonad developmental stage of shovelnose sturgeon. The short duration of the procedure and the high postprocedure survival suggest that this technique is suitable for shovelnose sturgeon and perhaps for the evaluation of other endangered fish species (e.g., pallid sturgeon S. alba) as well.

  18. Vulnerability of age-0 pallid sturgeon Scaphirhynchus albus to fish predation

    USGS Publications Warehouse

    French, William E.; Graeb, B.D.S.; Chipps, S.R.; Bertrand, K.N.; Selch, T.M.; Klumb, R.A.

    2010-01-01

    Stocking is a commonly employed conservation strategy for endangered species such as the pallid sturgeon, Scaphirhynchus albus. However, decisions about when, where and at what size pallid sturgeon should be stocked are hindered because vulnerability of pallid sturgeon to fish predation is not known. The objective of this study was to evaluate the vulnerability of age-0 pallid sturgeon to predation by two Missouri River predators under different flow regimes, and in combination with alternative prey. To document vulnerability, age-0 pallid sturgeon (<100 mm) were offered to channel catfish Ictalurus punctatus and smallmouth bass Micropterus dolomieu in laboratory experiments. Selection of pallid sturgeon by both predators was measured by offering pallid sturgeon and an alternative prey, fathead minnows Pimephales promelas, in varying prey densities. Smallmouth bass consumed more age-0 pallid sturgeon (0.95 h-1) than did channel catfish (0.13 h-1), and predation rates did not differ between water velocities supporting sustained (0 m s-1) or prolonged swimming speeds (0.15 m s-1). Neither predator positively selected pallid sturgeon when alternative prey was available. Both predator species consumed more fathead minnows than pallid sturgeon across all prey density combinations. Results indicate that the vulnerability of age-0 pallid sturgeon to predation by channel catfish and smallmouth bass is low, especially in the presence of an alternative fish prey. ?? 2009 Blackwell Verlag GmbH.

  19. Characterization of Gulf sturgeon diel and seasonal activity in the Pensacola Bay system, Florida

    NASA Astrophysics Data System (ADS)

    Wrege, Beth Marie

    2009-12-01

    We assess temporal and spatial distribution and diel variability in activity of Gulf of Mexico sturgeon Acipenser oxyrinchus desotoi in the Pensacola Bay system, Florida, using stationary ultrasonic telemetry. Gulf of Mexico sturgeon (n = 54) migrated through the bay system in fall to wintering areas in the Gulf of Mexico and Santa Rosa Sound. In spring, sturgeon migrated back through the bay system to summering habitats in rivers. Gulf of Mexico sturgeon use East Bay and Escambia Bay primarily as migration routes between riverine areas used in spring and summer and the Gulf of Mexico used in winter. North Central Pensacola Bay was not routinely frequented. Gulf of Mexico sturgeon used specific areas within the Pensacola Bay system in summer and winter not previously documented as essential sturgeon habitat. Areas in southeastern Pensacola were used heavily during winter by a portion of the population. Gulf of Mexico sturgeon also exhibited long-term winter residency in Santa Rosa Sound. Interestingly, an area in northeastern Escambia Bay supported Gulf of Mexico sturgeon in summer. This observation was unexpected; however, the identification of Gulf of Mexico sturgeon in this area at this time has important ecological and management implications. Gulf of Mexico sturgeon exhibited a strong diel activity pattern. Gulf of Mexico sturgeon were more active at night than during day in all seasons but summer. The use of prepositioned arrays of acoustic receivers not only provides continuous data within a defined area, but provides insights into nocturnal behavior not previously examined.

  20. Biological assessment for the shortnose sturgeon, Acipenser brevirostrum Lesueur 1818, the Savannah River Plant

    SciTech Connect

    Muska, C.; Matthews, R.A.

    1983-10-01

    The shortnose sturgeon (Acipenser brevirostrum) is listed as an endangered species in the United States. Prior to 1982, the presence of shortnose sturgeon had not been documented in the middle reaches of the Savannah River. However, shortnose sturgeon larvae were collected in 1982-1983 near the Savannah River Plant (SRP), a US Department of Energy (DOE) facility, as part of the SRP aquatic ecology program. This biological assessment was prepared to evaluate the potential impacts of present and proposed SRP operations on the shortnose sturgeon. This assessment is based on existing information on the life history and habitat preferences of the shortnose sturgeon, a description of the Savannah River Plant including plant operations which may potentially impact the shortnose sturgeon and consultations with local experts. From this information, it is concluded that the existing and proposed operations (specifically L-Reactor operation) of the Savannah River Plant will not affect the continued existence of the shortnose sturgeon the Savannah River.

  1. Assessing the risk to green sturgeon from application of imidacloprid to control burrowing shrimp in Willapa Bay, Washington--Part II: controlled exposure studies.

    PubMed

    Frew, John A; Grue, Christian E

    2015-11-01

    The activities of 2 species of burrowing shrimp have a negative impact on the growth and survival of oysters reared on intertidal mudflats in Willapa Bay and Grays Harbor, Washington (USA). To maintain viable harvests, oyster growers proposed the application of the neonicotinoid insecticide imidacloprid onto harvested beds for the control of burrowing shrimp. In test applications, water column concentrations of imidacloprid were relatively low and dissipated rapidly. The foraging activities of the green sturgeon (listed in the US Endangered Species Act) could result in exposure to higher, more sustained imidacloprid concentrations within sediment porewater and from the consumption of contaminated shrimp. Controlled experiments were conducted using surrogate white sturgeon to determine acute and chronic effect concentrations, to examine overt effects at more environmentally realistic concentrations and durations of exposure, and to assess chemical depuration. The 96-h median lethal concentration was 124 mg L(-1) , and the predicted 35-d no-observed-adverse-effect concentration was 0.7 mg L(-1) . No overt effects were observed following environmentally relevant exposures. Imidacloprid half-life in plasma was greater than 32 h. Measured concentrations of imidacloprid in porewater were significantly lower than the derived acute and chronic effect concentrations for white sturgeon. Exposure risk quotients were calculated using the effect concentrations and estimated environmental exposure. The resulting values were considerably below the level of concern for direct effects from either acute or chronic exposure to an endangered species. PMID:26351255

  2. Assessing the risk to green sturgeon from application of imidacloprid to control burrowing shrimp in Willapa Bay, Washington--Part II: controlled exposure studies.

    PubMed

    Frew, John A; Grue, Christian E

    2015-11-01

    The activities of 2 species of burrowing shrimp have a negative impact on the growth and survival of oysters reared on intertidal mudflats in Willapa Bay and Grays Harbor, Washington (USA). To maintain viable harvests, oyster growers proposed the application of the neonicotinoid insecticide imidacloprid onto harvested beds for the control of burrowing shrimp. In test applications, water column concentrations of imidacloprid were relatively low and dissipated rapidly. The foraging activities of the green sturgeon (listed in the US Endangered Species Act) could result in exposure to higher, more sustained imidacloprid concentrations within sediment porewater and from the consumption of contaminated shrimp. Controlled experiments were conducted using surrogate white sturgeon to determine acute and chronic effect concentrations, to examine overt effects at more environmentally realistic concentrations and durations of exposure, and to assess chemical depuration. The 96-h median lethal concentration was 124 mg L(-1) , and the predicted 35-d no-observed-adverse-effect concentration was 0.7 mg L(-1) . No overt effects were observed following environmentally relevant exposures. Imidacloprid half-life in plasma was greater than 32 h. Measured concentrations of imidacloprid in porewater were significantly lower than the derived acute and chronic effect concentrations for white sturgeon. Exposure risk quotients were calculated using the effect concentrations and estimated environmental exposure. The resulting values were considerably below the level of concern for direct effects from either acute or chronic exposure to an endangered species.

  3. Effects of arabinoxylan-oligosaccharides (AXOS) on juvenile Siberian sturgeon (Acipenser baerii) performance, immune responses and gastrointestinal microbial community.

    PubMed

    Geraylou, Zahra; Souffreau, Caroline; Rurangwa, Eugene; D'Hondt, Sofie; Callewaert, Lien; Courtin, Christophe M; Delcour, Jan A; Buyse, Johan; Ollevier, Frans

    2012-10-01

    Arabinoxylan-oligosaccharides (AXOS) are a newly discovered class of candidate prebiotics that exert different properties depending on their structure. In this study the effects of two different structures of AXOS, namely AXOS-32-0.30 (average degree of polymerization: 32, average degree of substitution: 0.30) and AXOS-3-0.25, were investigated on growth performance, immune responses, gut microbial fermentation and gut bacterial composition of juvenile Siberian sturgeon (Acipenser baerii). After a two weeks acclimation, fish (25.9 ± 0.9 g) were distributed over 24 aquariums (8 replicates per treatment) and fed a control diet or a diet containing 2% AXOS-32-0.30 or AXOS-3-0.25 for 12 weeks. Growth performance and feed utilization tend to improve in sturgeon fed on diets supplemented with AXOS-32-0.30, however not significant. Survival was high in all groups. Both AXOS preparations significantly enhanced the phagocytic activity of fish macrophages compared to the control group, while the alternative haemolytic complement activity and total serum peroxidase content improved only in the group fed AXOS-32-0.30 (P < 0.05). The lysozyme activity was not affected by AXOS addition. Simultaneously, the amount of short-chain fatty acids (SCFAs) was highest in the hind gut of sturgeon fed AXOS-32-0.30. The concentrations of acetate, butyrate and total SCFAs in fish fed AXOS-32-0.30 was significantly higher than in the groups fed the control diet or AXOS-3-0.25. Study of the bacterial community in the sturgeon hindgut using PCR-denaturing gradient gel electrophoresis (PCR-DGGE) revealed that both preparations of AXOS induced changes in the bacterial composition. According to redundancy analysis (RDA), hindgut microbiota of each treatment group clustered apart from one another (P = 0.001). DNA sequencing of the dominant DGGE bands recovered from the different treatments showed that AXOS mainly stimulated the growth of lactic acid bacteria and Clostridium sp., with more

  4. Effect of dietary macronutrient proportion on intermediate metabolism and oxidative status in sturgeon (Acipenser naccarii) and trout (Oncorhynchus mykiss): comparative study.

    PubMed

    Furné, M; García-Gallego, M; Hidalgo, M C; Sanz, A

    2016-08-01

    Three isoenergetic diets varying the proportion of dietary energy supplied by each of the macronutrients (carbohydrate, lipid, or protein) were delivered, to farmed sturgeon (Acipenser naccarii) and trout (Oncorhynchus mykiss), to test the possible effects on the intermediate metabolism and oxidative status in liver, white muscle, and heart. In trout, there is an adaptive metabolic response to an increase in lipids and carbohydrates in the diet. However, this does not happen in the sturgeon. These differences may be due to different dietary habits of both species. In terms of oxidative status, only the liver displayed oxidative stress in both species, showing an increase in the lipid peroxidation and antioxidant enzyme activities after feeding with the high-lipid and high-protein diet.

  5. The Gulf Sturgeon in the Suwannee River - Questions and Answers

    USGS Publications Warehouse

    Sulak, Kenneth J.; Randall, Michael

    2009-01-01

    Sturgeons and paddlefishes are modern descendants of an ancient group of freshwater fishes, the Chondrostei (a group of bony fishes with mostly cartilaginous skeletons). Sturgeons evolved during the Age of the Dinosaurs, and have prospered in the large rivers and lakes of North America, Europe and Asia for 200 million years. Together with alligators and crocodiles, they survived the mass extinction at the end of the Mesozoic Era, when the dinosaurs and many other groups of animals disappeared forever. They originated prior to the creation of the Atlantic Ocean, when the Northern Hemisphere supercontinent Pangea broke into North America and Eurasia. Most sturgeons are highly specialized to feed in the sediment on small invertebrate prey, a radical evolutionary departure from most of their fish-eating ancestors.

  6. The complete mitochondrial genome of Chinese sturgeon (Acipenser sinensis).

    PubMed

    Liao, Xiaolin; Tian, Hua; Zhu, Bin; Chang, Jianbo

    2016-01-01

    The complete mitochondrial genome of Chinese sturgeon (Acipenser sinensis) was determined by direct sequencing of PCR products. The Chinese sturgeon mitochondrial DNA is a circular molecule (16,688 bp in length) with the typical gene arrangement of vertebrate mtDNA, containing 13 protein-coding genes, two ribosomal RNA and 22 transfer RNA genes, and a non-coding control region. Its control region contains 4.5 copies of unit with 82 bp long at 5' end, which has been reported before for this species. Phylogenetic tree based on 13 protein-coding genes confirmed that the complete mtDNA sequence of Chinese sturgeon was reported here for the first time.

  7. Is that Your Mom? A Qualitative Investigation of White Mothers of Non-White Children in the United States and in New Zealand

    ERIC Educational Resources Information Center

    Robinson-Wood, Tracy Lynn

    2010-01-01

    Twenty-eight biological and adoptive White mothers of non-White children were interviewed in New Zealand and in the United States. Through a thematic analysis of transcribed interviews and interview notes, 7 primary themes emerged (a) looking like a family means looking alike and looking White, (b) mothering as vulnerability, (c) teen girls'…

  8. Investigation of spectral shifts in a white light interferometer with a single interference peak

    NASA Astrophysics Data System (ADS)

    Xu, Chunhui; Yi, Yingyan; Shu, Zhuo; Li, Min

    2015-04-01

    When the optical path difference between the two arms of an interferometer is so small that only one peak exists within the measurable interference spectrum, traditional white light interference demodulation techniques based on two adjacent interference peaks are not a suitable choice. We report an experimental approach to measure the peak wavelength shifts with only a single interference peak in a fiber white light interferometer. The temperature measurement experiments prove a linear relationship between the peak wavelength and the temperature. The temperature resolution is 0.1°C in theory.

  9. The Missouri River Scaphirhynchus albus (pallid sturgeon) effects analysis

    USGS Publications Warehouse

    Jacobson, Robert B.

    2016-08-05

    The Missouri River Pallid Sturgeon Effects Analysis (EA) was designed to assess how Missouri River management has affected—and may affect—the endangered Scaphirhynchus albus (pallid sturgeon) population. The EA emerged from the recognition that the direction and focus of the Missouri River Recovery Program would benefit from an updated, thorough evaluation of what is known, what is not known, and what needs to be known for effective actions. This fact sheet documents the steps in the EA process and the four core reports, culminating in the 2016 integrative report.

  10. The complete mitochondrial genome of Russian sturgeon (Acipenser gueldenstaedti).

    PubMed

    Dong, Chuanju; Chen, Baohua; Xu, Jian; Mahboob, Shahid; Al-Ghanim, K; Xu, Peng; Sun, Xiaowen

    2016-01-01

    Russian sturgeon (Acipenser gueldenstaedti) belongs to the Acipenseriformes Acipenseridae. In this study, we sequenced and characterized the complete mitochondrial genome of A. gueldenstaedti from National Sturgeon Hatchery, Chinese Academy of Fishery Sciences. The circular mitochondrial genome was determined to be 16,595 bp in length including 13 protein-coding genes, 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs) and 1 control region. The complete mitochondrial genome of A. gueldenstaedti provides basic genome data for relative studies on Acipenseriformes.

  11. Assessment of lake sturgeon (Acipenser fulvescens) spawning efforts in the lower St. Clair River, Michigan

    USGS Publications Warehouse

    Nichols, S. Jerrine; Kennedy, Gregory; Crawford, Eric; Allen, Jeffrey; French, John; Black, Glen; Blouin, Marc; Hickey, James P.; Chernyak, Sergei; Haas, Robert; Thomas, Michael

    2003-01-01

    One of the most threatened remaining populations of lake sturgeon in the Great Lakes is found in the connecting channels between Lake Huron and Lake Erie. Only two spawning grounds are presently known to be active in this region, and both are in the St. Clair River. The spawning reef in the St. Clair River delta has been recently colonized by round gobies (Neogobius melanostomus) in densities up to 25/m2, raising concerns regarding predation on the benthic-oriented eggs and larvae of the sturgeon. Investigations in 1998–1999 showed that while round goby predation does occur, a number of other factors may be equally affecting sturgeon spawning success, including few spawning adults (< 60), suspected poaching pressure, low retention rate of eggs on the reef, low hatch rate (~0.5%), the presence of organic contaminants, and predation from native and exotic invertebrates and fish. Overall, we estimate that less than 1% of the eggs deposited during a spawning run survive to hatch. We were able to increase the egg hatch rate to 16% by placing eggs in predator-exclusion chambers on the reef. The fate of the larvae is uncertain. Two weeks after hatching, no larvae were found on the reef. We were unable to find them anywhere else in the river, nor was predation on larvae noted in either year. There were factors other than predation affecting larval survival in 1999. There was a higher silt load on the reef than in 1998 and large numbers of dead larvae were found. Recruitment success from this site could be improved by utilizing techniques to increase the number of eggs on the reef, such as reducing the illegal take of adult fish and by placing eggs in predator-exclusion chambers to increase hatch rate.

  12. Alternative method of removing otoliths from sturgeon

    USGS Publications Warehouse

    Chalupnicki, Marc A.; Dittman, Dawn E.

    2016-01-01

    Extracting the otoliths (ear bones) from fish that have very thick skulls can be difficult and very time consuming. The common practice of making a transverse vertical incision on the top of the skull with a hand or electrical saw may damage the otolith if not performed correctly. Sturgeons (Acipenseridae) are one family in particular that have a very large and thick skull. A new laboratory method entering the brain cavity from the ventral side of the fish to expose the otoliths was easier than other otolith extraction methods found in the literature. Methods reviewed in the literature are designed for the field and are more efficient at processing large quantities of fish quickly. However, this new technique was designed to be more suited for a laboratory setting when time is not pressing and successful extraction from each specimen is critical. The success of finding and removing otoliths using this technique is very high and does not compromise the structure in any manner. This alternative technique is applicable to other similar fish species for extracting the otoliths.

  13. Geochemical Investigation of Source Water to Cave Springs, Great Basin National Park, White Pine County, Nevada

    USGS Publications Warehouse

    Prudic, David E.; Glancy, Patrick A.

    2009-01-01

    Cave Springs supply the water for the Lehman Caves Visitor Center at Great Basin National Park, which is about 60 miles east of Ely, Nevada, in White Pine County. The source of water to the springs was investigated to evaluate the potential depletion caused by ground-water pumping in areas east of the park and to consider means to protect the supply from contamination. Cave Springs are a collection of several small springs that discharge from alluvial and glacial deposits near the contact between quartzite and granite. Four of the largest springs are diverted into a water-collection system for the park. Water from Cave Springs had more dissolved strontium, calcium, and bicarbonate, and a heavier value of carbon-13 than water from Marmot Spring at the contact between quartzite and granite near Baker Creek campground indicating that limestone had dissolved into water at Cave Springs prior to discharging. The source of the limestone at Cave Springs was determined to be rounded gravels from a pit near Baker, Nevada, which was placed around the springs during the reconstruction of the water-collection system in 1996. Isotopic compositions of water at Cave Springs and Marmot Spring indicate that the source of water to these springs primarily is from winter precipitation. Mixing of water at Cave Springs between alluvial and glacial deposits along Lehman Creek and water from quartzite is unlikely because deuterium and oxygen-18 values from a spring discharging from the alluvial and glacial deposits near upper Lehman Creek campground were heavier than the deuterium and oxygen-18 values from Cave Springs. Additionally, the estimated mean age of water determined from chlorofluorocarbon concentrations indicates water discharging from the spring near upper Lehman Creek campground is younger than that discharging from either Cave Springs or Marmot Spring. The source of water at Cave Springs is from quartzite and water discharges from the springs on the upstream side of the

  14. Sex-Dependent Influences of Obesity on Cerebral White Matter Investigated by Diffusion-Tensor Imaging

    PubMed Central

    Horstmann, Annette; Lepsien, Jöran; Busse, Franziska; Mohammadi, Siawoosh; Schroeter, Matthias L.; Stumvoll, Michael; Villringer, Arno; Pleger, Burkhard

    2011-01-01

    Several studies have shown that obesity is associated with changes in human brain function and structure. Since women are more susceptible to obesity than men, it seems plausible that neural correlates may also be different. However, this has not been demonstrated so far. To address this issue, we systematically investigated the brain's white matter (WM) structure in 23 lean to obese women (mean age 25.5 y, std 5.1 y; mean body mass index (BMI) 29.5 kg/m2, std 7.3 kg/m2) and 26 lean to obese men (mean age 27.1 y, std 5.0 y; mean BMI 28.8 kg/m2, std 6.8 kg/m2) with diffusion-weighted magnetic resonance imaging (MRI). There was no significant age (p>0.2) or BMI (p>0.7) difference between female and male participants. Using tract-based spatial statistics, we correlated several diffusion parameters including the apparent diffusion coefficient, fractional anisotropy (FA), as well as axial (λ∥) and radial diffusivity (λ⊥) with BMI and serum leptin levels. In female and male subjects, the putative axon marker λ∥ was consistently reduced throughout the corpus callosum, particularly in the splenium (r = −0.62, p<0.005). This suggests that obesity may be associated with axonal degeneration. Only in women, the putative myelin marker λ⊥ significantly increased with increasing BMI (r = 0.57, p<0.005) and serum leptin levels (r = 0.62, p<0.005) predominantly in the genu of the corpus callosum, suggesting additional myelin degeneration. Comparable structural changes were reported for the aging brain, which may point to accelerated aging of WM structure in obese subjects. In conclusion, we demonstrate structural WM changes related to an elevated body weight, but with differences between men and women. Future studies on obesity-related functional and structural brain changes should therefore account for sex-related differences. PMID:21494606

  15. Influence of Glutamine Supplementation on Motility and Fertilization Success of Frozen-Thawed Persian Sturgeon (Acipenser persicus) Sperm.

    PubMed

    Aramli, M S; Golshahi, K; Nazari, R M; Golpour, A; Aramli, S

    2016-08-01

    Amino acids have an important biological role for the prevention of cell damage during cryopreservation. The aim of this study was to investigate the effects of glutamine on post-thaw sperm motility and fertilization success in the Persian sturgeon (Acipenser persicus). Sperm collected from six fish was cryopreserved in extenders containing different glutamine concentrations (2.5, 5 and 10 mm). Sperm samples diluted at the ratio of 1 : 1 using the extenders were subjected to cryopreservation. After dilution, the sperm suspensions were sucked into 250-μl straws; the straws were placed on the tray, frozen in nitrogen vapour and plunged into liquid nitrogen. Then, sperm were thawed in a water bath at 40°C for 5 s and used for analysis. Our results revealed that an increase in the concentration of glutamine caused a significant increase in the motility percentage, curvilinear velocity (VCL) and also fertilization success in the Persian sturgeon (p < 0.05). Comparing all concentrations of glutamine, the best concentration for sperm motility and fertilization rate was 10 mm. In addition, higher post-thaw motility percentage, VCL, and fertilization and hatching rates were obtained with the extender at the concentration of 10 mm (p < 0.05). The findings of this study showed that glutamine was of greater benefit to Persian sturgeon sperm motility during frozen-thawed process.

  16. A model to locate potential areas for lake sturgeon spawning habitat construction in the St. Clair–Detroit River System

    USGS Publications Warehouse

    Bennion, David; Manny, Bruce A.

    2014-01-01

    In response to a need for objective scientific information that could be used to help remediate loss of fish spawning habitat in the St. Clair River and Detroit River International Areas of Concern, this paper summarizes a large-scale geographic mapping investigation. Our study integrates data on two variables that many riverine fishes respond to in selecting where to spawn in these waters (water flow velocity and water depth) with available maps of the St. Clair–Detroit River System (SC–DRS). Our objectives were to locate and map these two physical components of fish habitat in the St. Clair and Detroit rivers and Lake St. Clair using a geographic information system (GIS) and to identify where, theoretically, fish spawning habitat could be remediated in these rivers. The target fish species to which this model applies is lake sturgeon (Acipenser fulvescens), but spawning reefs constructed for lake sturgeon in this system have been used for spawning by 17 species of fish. Our analysis revealed areas in each river that possessed suitable water velocity and depth for fish spawning and therefore could theoretically be remediated by the addition of rock-rubble substrate like that used at two previously remediated sites in the Detroit River at Belle Isle and Fighting Island. Results of our analysis revealed that only 3% of the total area of the SC–DRS possesses the necessary combination of water depth and high flow velocity to be indicated by the model as potential spawning habitat for lake sturgeon.

  17. Mycobacterium chelonae associated with tumor-like skin and oral masses in farmed Russian sturgeons (Acipenser gueldenstaedtii)

    PubMed Central

    2014-01-01

    Background Non-tuberculous mycobacteria responsible for piscine mycobacteriosis usually produce visceral granulomas in both freshwater and marine species. In this study, the first occurrence of Mycobacterium chelonae associated with tumor-like lesions in the Russian sturgeon (Acipenser gueldenstaedtii) is reported. Fifteen sturgeons from an Italian fish farm showing skin and oral cauliflower-like masses were investigated by histopathology, bacterial culture and molecular analyses. Results A total of 20 masses different in size located in the mouth and in pectoral and caudal fins (characterized by abundant calcium deposits and by mild to moderate granulomatous inflammation) were observed with a significant different degree of histological severity. All internal organs of the fish were negative for mycobacteria, Ziehl-Neelsen was positive in only one of the oral masses, whereas bacterial and PCR analyses detected the presence of M. chelonae for almost all the skin and oral masses. Based on these results, a calcinosis of dystrophic origin associated with a chronic granulomatous inflammation was considered as a primary diagnosis consequent to tissue injury in areas susceptible to trauma. Conclusions We hypothesized that the occurrence of M. chelonae in farmed sturgeons was only a secondary event related to its presence in a stressful rearing environment and subsequent to a dystrophic calcinosis occurred in previously damaged tissues. PMID:24423126

  18. Effects of estradiol-17β implantation on ovarian growth, sex steroid levels and vitellogenin proxies in previtellogenic sturgeon Huso huso.

    PubMed

    Akhavan, Sobhan R; Falahatkar, Bahram; Gilani, Mohammad H Tolouei; Lokman, P Mark

    2015-06-01

    Sexual development in female great sturgeon (Huso huso) is arrested at the previtellogenic stage for many years. The present study investigated the effects of different levels of estradiol-17β (E2) on gonadal development, levels of sex steroids and proxies of vitellogenin in 3-year-old cultured previtellogenic great sturgeon. Fish were intraperitoneally implanted every 1.5 months over a 6-month period from January to July with capsules filled with 0, 3, 6 or 12 mg E2/kg body mass as control, low, mid and high experimental groups, respectively. Blood sampling was performed at the start of experimentation and 3 weeks after each implantation for quantification of sex steroid levels and of vitellogenin-associated variables (triacylglycerol, cholesterol, calcium, phosphorus). Gonad biopsy samples were taken at the beginning and the end of the experiment in order to determine the gonad stage and oocyte morphometrical measures were taken to evaluate treatment effects. E2 implants produced a significant elevation in serum concentrations of E2, calcium, triacylglycerol, cholesterol and phosphorus. A rapid significant decrease was observed in serum testosterone levels in a dose-independent manner, so that the highest testosterone concentrations were observed in control fish throughout the experiment. There were no significant differences in oocyte stage or morphometric end points among the treated fish. We conclude that E2 implants do not stimulate ovarian growth, and hence, E2 implants alone are insufficient to reducing the time until onset of sexual maturation in previtellogenic great sturgeon.

  19. Effects of estradiol-17β implantation on ovarian growth, sex steroid levels and vitellogenin proxies in previtellogenic sturgeon Huso huso.

    PubMed

    Akhavan, Sobhan R; Falahatkar, Bahram; Gilani, Mohammad H Tolouei; Lokman, P Mark

    2015-06-01

    Sexual development in female great sturgeon (Huso huso) is arrested at the previtellogenic stage for many years. The present study investigated the effects of different levels of estradiol-17β (E2) on gonadal development, levels of sex steroids and proxies of vitellogenin in 3-year-old cultured previtellogenic great sturgeon. Fish were intraperitoneally implanted every 1.5 months over a 6-month period from January to July with capsules filled with 0, 3, 6 or 12 mg E2/kg body mass as control, low, mid and high experimental groups, respectively. Blood sampling was performed at the start of experimentation and 3 weeks after each implantation for quantification of sex steroid levels and of vitellogenin-associated variables (triacylglycerol, cholesterol, calcium, phosphorus). Gonad biopsy samples were taken at the beginning and the end of the experiment in order to determine the gonad stage and oocyte morphometrical measures were taken to evaluate treatment effects. E2 implants produced a significant elevation in serum concentrations of E2, calcium, triacylglycerol, cholesterol and phosphorus. A rapid significant decrease was observed in serum testosterone levels in a dose-independent manner, so that the highest testosterone concentrations were observed in control fish throughout the experiment. There were no significant differences in oocyte stage or morphometric end points among the treated fish. We conclude that E2 implants do not stimulate ovarian growth, and hence, E2 implants alone are insufficient to reducing the time until onset of sexual maturation in previtellogenic great sturgeon. PMID:25724452

  20. Cigarette advertising in magazines for Latinas, White women, and men, 1998--2002: a preliminary investigation.

    PubMed

    Fernandez, Senaida; Hickman, Norval; Klonoff, Elizabeth A; Landrine, Hope; Kashima, Kennon; Parekh, Bina; Brouillard, Catherine R; Zolezzi, Michelle; Jensen, Jennifer A; Weslowski, Zorahna

    2005-04-01

    Cigarette ads in popular magazines play a role in smoking and in brand preferences among women and men, but few studies have analyzed ads directed at women vs men, and no study has examined ads directed at women of different ethnic groups. Hence, we examined cigarette ads in popular magazines for White women, Latinas, and men 1998 through 2002 for the first time. Significant differences in the number of cigarette ads by magazine audience were found, along with significant differences in the type and brands of cigarettes advertised to each group. These preliminary findings suggest that the tobacco industry may target women in a manner that differs from its targeting of men, and may target Latinas in a manner that it does not target White women. Results are discussed in terms of the need for further research on tobacco ads directed at women.

  1. The black/white mortality crossover: investigation in a community-based study.

    PubMed

    Wing, S; Manton, K G; Stallard, E; Hames, C G; Tryoler, H A

    1985-01-01

    The black/white mortality crossover at about age 75, a result of lower white mortality rates at younger ages and lower black rates at the oldest ages, has been observed in U.S. vital statistics since 1900. Though a persistant observation in such data, its validity has been challenged by questions about census enumeration and age reporting on death certificates. Analyses of 20 years experience of all-cause mortality in the community-based Evans County Study using a Weibull model of age specific mortality rates showed a statistically significant black/white mortality crossover for both men (at age 73) and women (at age 85). The finding of a crossover in this longitudinally followed population is significant because the age reporting for both survivors and age at death for nonsurvivors were obtained in the study protocol and did not rely on age reporting either in census data or on the death certificate. Differences in the age and sex patterns of mortality between two populations living in the same geographic region are relevant to questions about the etiology of the major age-related chronic diseases as well as to topics of current interest in health care policy.

  2. Short-term storage of Atlantic sturgeon spermatozoa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is significant interest to restore the Atlantic sturgeon, a species of concern. Biologists are interested in both the short-term storage and cryopreservation of semen to maximize availability of viable spermatozoa whenever a rare ripe female is found and available for spawning. We conducted sh...

  3. Captive breeding programs based on family groups in polyploid sturgeons.

    PubMed

    Boscari, Elisa; Pujolar, Jose Martin; Dupanloup, Isabelle; Corradin, Riccardo; Congiu, Leonardo

    2014-01-01

    In species with long life cycles and discontinuous availability of individuals to reproduction, implementing a long-term captive breeding program can be difficult or impossible. In such cases, managing diversity among familiar groups instead of individuals could become a suitable approach to avoid inbreeding and increase the possibility to accomplish a breeding scheme. This is the case of several sturgeon species including the Adriatic sturgeon, whose recovery depends on the management of a few captive stocks directly descended from the same group of wild parents. In the present study, relatedness among 445 potential breeders was inferred with a novel software for pedigree reconstruction in tetraploids ("BreedingSturgeons"). This information was used to plan a breeding scheme considering familiar groups as breeding units and identifying mating priorities. A two-step strategy is proposed: a short-term breeding program, relying on the 13 remaining F0 individuals of certain wild origin; and a long-term plan based on F1 families. Simulations to evaluate the loss of alleles in the F2 generation under different pairing strategies and assess the number of individuals to breed, costs and logistical aquaculture constraints were performed. The strategy proposed is transferable to the several other tetraploid sturgeon species on the brink of extinction.

  4. Population status of North American green sturgeon, Acipenser medirostris

    USGS Publications Warehouse

    Adams, P.B.; Grimes, C.; Hightower, J.E.; Lindley, S.T.; Moser, M.L.; Parsley, M.J.

    2007-01-01

    North American green sturgeon, Acipenser medirostris, was petitioned for listing under the Endangered Species Act (ESA). The two questions that need to be answered when considering an ESA listing are; (1) Is the entity a species under the ESA and if so (2) is the "species" in danger of extinction or likely to become an endangered species in the foreseeable future throughout all or a significant portion of its range? Green sturgeon genetic analyses showed strong differentiation between northern and southern populations, and therefore, the species was divided into Northern and Southern Distinct Population Segments (DPSs). The Northern DPS includes populations in the Rogue, Klamath-Trinity, and Eel rivers, while the Southern DPS only includes a single population in the Sacramento River. The principal risk factors for green sturgeon include loss of spawning habitat, harvest, and entrainment. The Northern DPS is not considered to be in danger of extinction or likely to become an endangered species in the foreseeable future. The loss of spawning habitat is not large enough to threaten this DPS, although the Eel River has been severely impacted by sedimentation due to poor land use practices and floods. The two main spawning populations in the Rogue and Klamath-Trinity rivers occupy separate basins reducing the potential for loss of the DPS through catastrophic events. Harvest has been substantially reduced and green sturgeon in this DPS do not face substantial entrainment loss. However there are significant concerns due to lack of information, flow and temperature issues, and habitat degradation. The Southern DPS is considered likely to become an endangered species in the foreseeable future. Green sturgeon in this DPS are concentrated into one spawning area outside of their natural habitat in the Sacramento River, making them vulnerable to catastrophic extinction. Green sturgeon spawning areas have been lost from the area above Shasta Dam on the Sacramento River and

  5. Distribution and movement of shortnose sturgeon (Acipenser brevirostrum) in the Chesapeake Bay

    USGS Publications Warehouse

    Welsh, S.A.; Mangold, M.F.; Skjeveland, J.E.; Spells, A.J.

    2002-01-01

    During a reward program for Atlantic sturgeon (Acipenser oxyrinchus), 40 federally endangered shortnose sturgeon (Acipenser brevirostrum) were captured and reported by commercial fishers between January 1996 and January 2000 from the Chesapeake Bay. Since this is more than double the number of published records of shortnose sturgeon in the Chesapeake Bay between 1876 and 1995, little information has been available on distributions and movement. We used fishery dependent data collected during the reward program to determine the distribution of shortnose sturgeon in the Chesapeake Bay. Sonically-tagged shortnose sturgeon in the Chesapeake Bay and Delaware River were tracked to determine if individuals swim through the Chesapeake and Delaware Canal. Shortnose sturgeon were primarily distributed within the upper Chesapeake Bay. The movements of one individual, tagged within the Chesapeake Bay and later relocated in the canal and Delaware River, indicated that individuals traverse the Chesapeake and Delaware Canal.

  6. Physical and hormonal examination of Missouri River shovelnose sturgeon reproductive stage: A reference guide

    USGS Publications Warehouse

    Wildhaber, M.L.; Papoulias, D.M.; DeLonay, A.J.; Tillitt, D.E.; Bryan, J.L.; Annis, M.L.

    2007-01-01

    From May 2001 to June 2002 Wildhaber et al. (2005) conducted monthly sampling of Lower Missouri River shovelnose sturgeon (Scaphirhynchus platorynchus) to develop methods for determination of sex and the reproductive stage of sturgeons in the field. Shovelnose sturgeon were collected from the Missouri River and ultrasonic and endoscopic imagery and blood and gonadal tissue samples were taken. The full set of data was used to develop monthly reproductive stage profiles for S. platorynchus that could be compared to data collected on pallid sturgeon (Scaphirhynchus albus). This paper presents a comprehensive reference set of images, sex steroids, and vitellogenin (VTG, an egg protein precursor) data for assessing shovelnose sturgeon sex and reproductive stage. This reference set includes ultrasonic, endoscopic, histologic, and internal images of male and female gonads of shovelnose sturgeon at each reproductive stage along with complementary data on average 17-?? estradiol, 11-ketotestosterone, VTG, gonadosomatic index, and polarization index. ?? 2007 Blackwell Verlag.

  7. Induction of meiotic gynogenesis in ship sturgeon Acipenser nudiventris using UV-irradiated heterologous sperm.

    PubMed

    Hassanzadeh Saber, Mohammad; Noveiri, Shahrouz Baradaran; Pourkazemi, Mohammad; Yazdani, Mohammadali; Ghoroghi, Ahmad; Bahmani, Mahmoud; Pourdehghani, Mohammad; Chakmehdouz, Fereidoon; Yarmohammadi, Mahtab; Nowruzfashkhami, Mohammadreza

    2014-05-01

    Diploid gynogenesis was induced in ship sturgeon Acipenser nudiventris using UV-irradiated sperm from Siberian sturgeon Acipenser baerii. The optimal condition for the retention of the second polar body in ship sturgeon was determined to be 10 min after activation/fertilization in experiments. The temperature of cold shock and its duration were 2.5 °C and 30 min, respectively. A total of 30 gynogens of known parentage from experimental treatments were screened using microsatellite DNA analysis, and uniparental transmission in meiogens was confirmed. The results show that heterologous Siberian sturgeon sperm is applicable as UV-irradiated sperm for the induction of gynogenesis in ship sturgeon. This technique may recover the critically endangered sturgeon species that are becoming extinct.

  8. Radio Observations as a Tool to Investigate Shocks and Asymmetries in Accreting White Dwarf Binaries

    NASA Astrophysics Data System (ADS)

    Weston, Jennifer H. S.

    2016-07-01

    This dissertation uses radio observations with the Karl G. Jansky Very Large Array (VLA) to investigate the mechanisms that power and shape accreting white dwarfs (WD) and their ejecta. We test the predictions of both simple spherical and steady-state radio emission models by examining nova V1723 Aql, nova V5589 Sgr, symbiotic CH Cyg, and two small surveys of symbiotic binaries. First, we highlight classical nova V1723 Aql with three years of radio observations alongside optical and X-ray observations. We use these observations to show that multiple outflows from the system collided to create early non-thermal shocks with a brightness temperature of ≥106 K. While the late-time radio light curve is roughly consistent an expanding thermal shell of mass 2x10-4 M⊙ solar masses, resolved images of V1723 Aql show elongated material that apparently rotates its major axis over the course of 15 months, much like what is seen in gamma-ray producing nova V959 Mon, suggesting similar structures in the two systems. Next, we examine nova V5589 Sgr, where we find that the early radio emission is dominated by a shock-powered non-thermal flare that produces strong (kTx > 33 keV) X-rays. We additionally find roughly 10-5 M⊙ solar masses of thermal bremsstrahlung emitting material, all at a distance of ~4 kpc. The similarities in the evolution of both V1723 Aql and V5589 Sgr to that of nova V959 Mon suggest that these systems may all have dense equatorial tori shaping faster flows at their poles. Turning our focus to symbiotic binaries, we first use our radio observations of CH Cyg to link the ejection of a collimated jet to a change of state in the accretion disk. We additionally estimate the amount of mass ejected during this period (10-7 M⊙ masses), and improve measurements of the period of jet precession (P=12013 ± 74 days). We then use our survey of eleven accretion-driven symbiotic systems to determine that the radio brightness of a symbiotic system could potentially

  9. Estimation of gonad volume, fecundity, and reproductive stage of shovelnose sturgeon using sonography and endoscopy with application to the endangered pallid sturgeon

    USGS Publications Warehouse

    Bryan, J.L.; Wildhaber, M.L.; Papoulias, D.M.; DeLonay, A.J.; Tillitt, D.E.; Annis, M.L.

    2007-01-01

    Most species of sturgeon are declining in the Mississippi River Basin of North America including pallid (Scaphirhynchus albus F. and R.) and shovelnose sturgeons (S. platorynchus R.). Understanding the reproductive cycle of sturgeon in the Mississippi River Basin is important in evaluating the status and viability of sturgeon populations. We used non-invasive, non-lethal methods for examining internal reproductive organs of shovelnose and pallid sturgeon. We used an ultrasound to measure egg diameter, fecundity, and gonad volume; endoscope was used to visually examine the gonad. We found the ultrasound to accurately measure the gonad volume, but it underestimated egg diameter by 52%. After correcting for the measurement error, the ultrasound accurately measured the gonad volume but it was higher than the true gonad volume for stages I and II. The ultrasound underestimated the fecundity of shovelnose sturgeon by 5%. The ultrasound fecundity was lower than the true fecundity for stage III and during August. Using the endoscope, we viewed seven different egg color categories. Using a model selection procedure, the presence of four egg categories correctly predicted the reproductive stage ± one reproductive stage of shovelnose sturgeon 95% of the time. For pallid sturgeon, the ultrasound overestimated the density of eggs by 49% and the endoscope was able to view eggs in 50% of the pallid sturgeon. Individually, the ultrasound and endoscope can be used to assess certain reproductive characteristics in sturgeon. The use of both methods at the same time can be complementary depending on the parameter measured. These methods can be used to track gonad characteristics, including measuring Gonadosomatic Index in individuals and/or populations through time, which can be very useful when associating gonad characteristics with environmental spawning triggers or with repeated examinations of individual fish throughout the reproductive cycle.

  10. Estimation of gonad volume, fecundity, and reproductive stage of shovelnose sturgeon using sonography and endoscopy with application to the endangered pallid sturgeon

    USGS Publications Warehouse

    Bryan, J.L.; Wildhaber, M.L.; Papoulias, D.M.; DeLonay, A.J.; Tillitt, D.E.; Annis, M.L.

    2007-01-01

    Most species of sturgeon are declining in the Mississippi River Basin of North America including pallid (Scaphirhynchus albus F. and R.) and shovelnose sturgeons (S. platorynchus R.). Understanding the reproductive cycle of sturgeon in the Mississippi River Basin is important in evaluating the status and viability of sturgeon populations. We used non-invasive, non-lethal methods for examining internal reproductive organs of shovelnose and pallid sturgeon. We used an ultrasound to measure egg diameter, fecundity, and gonad volume; endoscope was used to visually examine the gonad. We found the ultrasound to accurately measure the gonad volume, but it underestimated egg diameter by 52%. After correcting for the measurement error, the ultrasound accurately measured the gonad volume but it was higher than the true gonad volume for stages I and II. The ultrasound underestimated the fecundity of shovelnose sturgeon by 5%. The ultrasound fecundity was lower than the true fecundity for stage III and during August. Using the endoscope, we viewed seven different egg color categories. Using a model selection procedure, the presence of four egg categories correctly predicted the reproductive stage ?? one reproductive stage of shovelnose sturgeon 95% of the time. For pallid sturgeon, the ultrasound overestimated the density of eggs by 49% and the endoscope was able to view eggs in 50% of the pallid sturgeon. Individually, the ultrasound and endoscope can be used to assess certain reproductive characteristics in sturgeon. The use of both methods at the same time can be complementary depending on the parameter measured. These methods can be used to track gonad characteristics, including measuring Gonadosomatic Index in individuals and/or populations through time, which can be very useful when associating gonad characteristics with environmental spawning triggers or with repeated examinations of individual fish throughout the reproductive cycle. ?? 2007 Blackwell Verlag.

  11. Denaturation and intermediates study of two sturgeon hemoglobins by n-dodecyl trimethylammonium bromide.

    PubMed

    Ariaeenejad, Shohreh; Habibi-Rezaei, Mehran; Kavousi, Kaveh; Jamili, Shahla; Fatemi, Mohammad Reza; Hong, Jun; Poursasan, Najmeh; Sheibani, Nader; Moosavi-Movahedi, Ali A

    2013-02-01

    Varieties of hemoglobin (Hb) forms exist in fish, which are usually well adapted to the different ecological conditions or various habitats. In the current study, Hbs from two Sturgeon species of the Southern Caspian Sea Basin were purified and studied upon interaction with n-dodecyl trimethylammonium bromide (DTAB; as a cationic surfactant) by various methods including UV-visible absorption, dynamic light scattering (DLS), and ANS fluorescence spectrophotometry. The chemometric analysis of Hbs was investigated upon interaction with DTAB under titration, using UV-visible absorption spectra. The chemometric resolution techniques were used to determine the number of the components and mole fraction of the oxidized Hbs. These results provided the evidence for the existence of three different molecular components including native (N), intermediate (I) and denatured (D) in sturgeon Hbs. According to the distribution of intermediates, which were broadened in a range of DTAB concentration, the aggregation states, DLS experiments, and thermal stability (T(m) obtained by differential scanning calorimetry (DSC)), the Acipenser stellatus Hb was more stable compared to Acipenser persicus Hb. These results demonstrate a significant relationship between the stability of fish Hbs and the habitat depth requirements.

  12. Denaturation and intermediates study of two sturgeon hemoglobins by n-dodecyl trimethylammonium bromide

    PubMed Central

    Ariaeenejad, Shohreh; Habibi-Rezaei, Mehran; Kavousi, Kaveh; Jamili, Shahla; Fatemi, Mohammad Reza; Hong, Jun; Poursasan, Najmeh; Sheibani, Nader; Moosavi-Movahedi, Ali. A.

    2013-01-01

    Varieties of hemoglobin (Hb) forms exist in fish, which are usually well adapted to the different ecological conditions or various habitats. In the current study, Hbs from two Sturgeon species of the Southern Caspian Sea Basin were purified and studied upon interaction with n-dodecyl trimethylammonium bromide (DTAB; as a cationic surfactant) by various methods including UV-visible absorption, dynamic light scattering (DLS), and ANS fluorescence spectrophotometry. The chemometric analysis of Hbs was investigated upon interaction with DTAB under titration, using UV-visible absorption spectra. The chemometric resolution techniques were used to determine the number of the components and mole fraction of the oxidized Hbs. These results provided the evidence for the existence of three different molecular components including native (N), intermediate (I) and denatured (D) in sturgeon Hbs. According to the distribution of intermediates, which were broadened in a range of DTAB concentration, the aggregation states, DLS experiments, and thermal stability (Tm obtained by differential scanning calorimetry (DSC)), the Acipenser stellatus Hb was more stable compared to Acipenser persicus Hb. These results demonstrate a significant relationship between the stability of fish Hbs and the habitat depth requirements. PMID:23142155

  13. Investigation of earth's albedo using Skylab data. [White Sands, New Mexico and Lake Michigan

    NASA Technical Reports Server (NTRS)

    Turner, R. E. (Principal Investigator)

    1976-01-01

    The author has identified the following significant results. Specific test sites in the White Sands, New Mexico and Lake Michigan areas were chosen because of their stability and known reflectances. Skylab S192 multispectral data and ERIM aircraft multispectral data were collected for these sites and were compared with results of atmospheric radiative transfer calculations in order to determine the aerosol content of the atmosphere. The spectral shape of the Skylab data compared quite favorably with the nearly simultaneous spectral character of the aircraft data. Although there were difficulties in the calibration of the S192 instrument which remain unresolved, interesting mathematical and physical relationships were discovered.

  14. The physiological performance and immune responses of juvenile Amur sturgeon (Acipenser schrenckii) to stocking density and hypoxia stress.

    PubMed

    Ni, Meng; Wen, Haishen; Li, Jifang; Chi, Meili; Bu, Yan; Ren, Yuanyuan; Zhang, Mo; Song, Zhifei; Ding, Houmeng

    2014-02-01

    Stocking density and hypoxia are considered priority issues in aquaculture research. In this study, two experiments were carried out in order to investigate the effects of chronic stress (stocking density) and acute stress (hypoxia) on the immune physiology responses (hematology, serum cortisol, glucose, total protein and the mRNA expression of CYP 1A) of juvenile Amur sturgeon (Acipenser schrenckii). In the chronic stress study, three triplicate groups of Amur sturgeon (42.0 ± 2.3 g) were reared in nine square concrete ponds (4.4 × 4.4 × 0.45 m³) at three stocking densities (3.7, 6.9 and 9.0 kg/m³) for 50 days. In the acute stress study, three triplicate groups: normal group (7 mg/l), hypoxia group 1 (5 mg/l) and hypoxia group 2 (3 mg/l) were used in nine 100 L indoor tanks. Sampling was performed at the end of the stocking density experiment (50 days) and at 0, 0.5, 1.5, 3 and 6 h after hypoxia stress. The results showed that increased stocking density reduced the morphological indexes (hepatosomatic index, spleen-somatic index and kidney-somatic index), while total protein and hemoglobin increased significantly in the stressed group. In response to hypoxia, the levels of cortisol, glucose and hematological parameters elevated significantly after this stress. As for spleen-somatic index, there was a decline after hypoxia though H1 group returned to the normal level at 3 h and 6 h after hypoxia stress. Additionally, In order to better understand the immune response of Amur sturgeon to chronic and acute stressors, we cloned the complete coding sequence of Amur sturgeon CYP 1A for the first time and investigated its tissue-specific expression and stress-induced expression. CYP 1A mRNA in liver showed over expressions both in crowding condition and in hypoxia stress. The same trend was also found in spleen and kidney which may provide evidence that CYP 1A could serve as a good indicator of immune response in Amur sturgeon. In addition, the result suggested a

  15. Migration and habitats of diadromous Danube River sturgeons in Romania: 1998-2000

    USGS Publications Warehouse

    Kynard, B.; Suciu, R.; Horgan, M.

    2002-01-01

    Upstream migrant adults of stellate sturgeon, Acipenser stellatus (10 in 1998, 43 in 1999) and Russian sturgeon, A. gueldenstaedtii (three in 1999) were captured at river km (rkm) 58-137, mostly in the spring, and tagged with acoustic tags offering a reward for return. The overharvest was revealed by tag returns (38% in 1998, 28% in 1999) and by harvest within 26 days (and before reaching spawning grounds) of the six stellate sturgeon tracked upstream. A drop-back of > 50% of the tagged sturgeon, some to the Black Sea, shows a high sensitivity to interruption of migration and capture/handling/holding. Harvesting and dropback prevented tracking of sturgeon to spawning sites. Gillnetting and tracking of stellate sturgeon showed that the autumn migration ended in early October (river temperature 16??C) and identified a likely wintering area at river km (rkm) 75-76 (St George Branch). Thus, fishery harvesting after early October captures wintering fish, not migrants. Rare shoreline cliffs in the lower river likely create the only rocky habitat for sturgeon spawning. A survey for potential spawning habitats found five sites with rocky substrate and moderate water velocity, all ???rkm 258. Drift netting caught early life-stages of 17 fish species and one sturgeon, a beluga, Huso huso, larva likely spawned at ???rkm 258. All diadromous Danube sturgeons likely spawn at ???rkm 258.

  16. Effects of commercial harvest on shovelnose sturgeon populations in the Upper Mississippi River

    USGS Publications Warehouse

    Koch, Jeff D.; Quist, Michael C.; Pierce, Clay L.; Hansen, Kirk A.; Steuck, Michael J.

    2009-01-01

    Shovelnose sturgeon Scaphirhynchus platorynchus have become an increasingly important commercial species in the upper Mississippi River (UMR) because of the collapse of foreign sturgeon (family Acipenseridae) populations and bans on imported caviar. In response to concerns about the sustainability of the commercial shovelnose sturgeon fishery in the UMR, we undertook this study to describe the demographics of the shovelnose sturgeon population and evaluate the influence of commercial harvest on shovelnose sturgeon populations in the UMR. A total of 1,682 shovelnose sturgeon were collected from eight study pools in 2006 and 2007 (Pools 4, 7, 9, 11, 13, 14, 16, and 18). Shovelnose sturgeon from upstream pools generally had greater lengths, weights, and ages than those from downstream pools. Additionally, mortality estimates were lower in upstream pools (Pools 4, 7, 9, and 11) than in downstream pools (Pools 13, 14, 16, and 18). Linear regression suggested that the slower growth of shovelnose sturgeon is a consequence of commercial harvest in the UMR. Modeling of potential management scenarios suggested that a 685-mm minimum length limit is necessary to prevent growth and recruitment overfishing of shovelnose sturgeon in the UMR.

  17. First documented occurrences of the shortnose sturgeon (Acipenser brevirostrum) in the Saco River, Maine, USA

    USGS Publications Warehouse

    Little, C.E.; Kieffer, M.; Wippelhauser, G.; Zydlewski, G.; Kinnison, M.; Whitefleet-Smith, L. A.; Sulikowski, J.A.

    2013-01-01

    During sampling efforts to study the more abundant Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus, between May of 2009 and November of 2011, four shortnose sturgeon were captured in gill nets near the mouth of the Saco River, Maine. Two of these individuals were tagged with acoustic transmitters to monitor their movement within the Saco River. Additionally, six shortnose sturgeon that had been tagged with acoustic transmitters in the Merrimack River, Massachusetts were detected on the acoustic array deployed within the Saco River and its estuary over this time period. These incidences represent the first verified documentation of shortnose sturgeon within this estuary.

  18. Sturgeon hatching enzyme and the mechanism of egg envelope digestion: Insight into changes in the mechanism of egg envelope digestion during the evolution of ray-finned fish.

    PubMed

    Nagasawa, Tatsuki; Kawaguchi, Mari; Sano, Kaori; Yasumasu, Shigeki

    2015-12-01

    We investigated the evolution of the hatching enzyme gene using bester sturgeon (hybrid of Acipencer ruthenus and Huso huso), a basal member of ray-finned fishes. We purified the bester hatching enzyme from hatching liquid, yielding a single band on SDS-PAGE, then isolated its cDNA from embryos by PCR. The sturgeon hatching enzyme consists of an astacin family protease domain and a CUB domain. The CUB domains are present in frog and bird hatching enzymes, but not in teleostei, suggesting that the domain structure of sturgeon hatching enzyme is the tetrapod type. The purified hatching enzyme swelled the egg envelope, and selectively cleaved one of five egg envelope proteins, ZPAX. Xenopus hatching enzyme preferentially digests ZPAX, thus, the egg envelope digestion process is conserved between amphibians and basal ray-finned fish. Teleostei hatching enzymes cleave the repeat sequences at the N-terminal region of ZPB and ZPC, suggesting that the targets of the teleostei hatching enzymes differ from those of amphibians and sturgeons. Such repeat sequences were not found in the N-terminal region of ZPB and ZPC of amphibians and sturgeons. Our results suggest that the change in substrates of the hatching enzymes was accompanied by the mutation of the amino acid sequence of N-terminal regions of ZPB and ZPC. We conclude that the changes in the mechanism of egg envelope digestion, including the change in the domain structure of the hatching enzymes and the switch in substrate, occurred during the evolution of teleostei, likely triggered by the teleost-specific third whole genome duplication. J. Exp. Zool. (Mol. Dev. Evol.) 324B: 720-732, 2015. © 2015 Wiley Periodicals, Inc.

  19. 77 FR 21539 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Sturgeon Research in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-10

    ... dolphins in 2011 as a result of entanglement and subsequent asphyxiation in gill nets deployed for sturgeon.... Although entanglement of marine mammals in gill nets deployed for sturgeon research is extremely rare,...

  20. Investigation of the white light coronal structure during the total solar eclipse on March 29, 2006

    NASA Astrophysics Data System (ADS)

    Stoeva, P.; Stoev, A.; Kuzin, S.; Shopov, Y.; Kiskinova, N.; Stoyanov, N.; Pertsov, A.

    2008-02-01

    Results from photographic observations of the white light solar corona conducted during the total phase of the total solar eclipse on March 29, 2006 in Manavgat, Turkey are shown in this work. Spectroscopic study of the green 530.3 nm line of Fe XIV in the corona of the Sun has also been made. The spectrograph was designed by specialists from the STIL-BAS "Acad. D. Mishev", Stara Zagora Department, Bulgaria; the Lebedev Physical Institute, Moscow, Russia; and the Yuri Gagarin Public Astronomical Observatory, Stara Zagora, Bulgaria. It has been found that the axis of symmetry of the "helmet"-type streamers is tilted towards the solar equator and the deviations from a radial direction in the western hemisphere are greater than those in the eastern one (21°/8°). The solar corona flattening is [epsilon]=0.098, which corresponds to an intermediate (before the minimum) type of corona. We have obtained that the solar cycle phase is [Phi]=0.17 for the 2006 TSE. White light corona is asymmetric, in contrast to solar corona observed during the August 11, 1999 total solar eclipse.

  1. Complex bacterial diversity in the white biofilms of the Catacombs of St. Callixtus in Rome evidenced by different investigation strategies.

    PubMed

    Krakova, Lucia; De Leo, Filomena; Bruno, Laura; Pangallo, Domenico; Urzì, Clara

    2015-05-01

    Roman Catacombs are affected by different kinds of biofilms that were extensively investigated in the last 14 years. In particular, the areas far from the lamps are often covered by white biofilms of different extension, consistency and nature. The aim of this paper is to describe the profile of the microbial community present in two areas of the Ocean's Cubiculum (CSC13), characterized by similar alterations described as white biofilms, by using a multistep approach that included direct microscopy observations, culture-dependent and culture-independent methodologies through the extraction of DNA and RNA directly from the sampled areas. In addition to this, we extracted the DNA directly from the Petri dishes containing R2A and B4 media after incubation and growth of bacteria. Our results evidenced that a complex bacterial community (mainly constituted by filamentous Actinobacteria, as well as Firmicutes and Proteobacteria) colonizes the two different white biofilms, and its detection, quantitative and qualitative, could be revealed only by different approaches, each method giving different information that only partially overlap.

  2. Plasma cholinesterase activity as a biomarker for quantifying exposure of green sturgeon to carbaryl following applications to control burrowing shrimp in Washington State.

    PubMed

    Troiano, Alexandra T; Grue, Christian E

    2016-08-01

    Willapa Bay (Washington State, USA) has been 1 of the rare intertidal locations where large-scale pesticide applications occur. Until recently, carbaryl was applied to control burrowing shrimp that decrease commercial oyster productivity. The bay is a critical habitat for green sturgeon (Acipenser medirostris), an anadromous species listed as threatened under the US Endangered Species Act. However, the hazard that carbaryl poses is unknown. Surrogate seawater-acclimated white sturgeon (A. transmontanus) were exposed to 0 μg L(-1) , 30 μg L(-1) , 100 μg L(-1) , 300 μg L(-1) , 1000 μg L(-1) , and 3000 μg L(-1) carbaryl for 6 h, and brain acetylcholinesterase (AChE) and plasma butyrylcholinesterase (BChE) activities were measured. Enzyme recovery was measured in an additional cohort exposed to 1000 μg L(-1) carbaryl for 6 h. Activity of AChE was reduced (p ≤ 0.001) at concentrations ≥ 100 μg L(-1) with recovery in the 1000 μg L(-1) cohort by 72 h. Surprisingly, BChE activity was greater than controls at concentrations ≥ 300 μg L(-1) (p > 0.05), a finding confirmed in additional fish exposed to 3000 μg L(-1) for 6 h (+30%, p < 0.001) with apparent recovery by 48 h. Plasma samples were collected from free-living green sturgeon before and 4 d to 5 d after application of carbaryl in Willapa Bay. Activity of BChE after application was reduced 28% (p < 0.001), indicating exposure to the pesticide. However, the lack of congruence between BChE and AChE activity in captive white sturgeon exposed to carbaryl indicates that further studies are needed to better understand the risk carbaryl exposure poses to green sturgeon. Environ Toxicol Chem 2016;35:2003-2015. © 2015 SETAC.

  3. Plasma cholinesterase activity as a biomarker for quantifying exposure of green sturgeon to carbaryl following applications to control burrowing shrimp in Washington State.

    PubMed

    Troiano, Alexandra T; Grue, Christian E

    2016-08-01

    Willapa Bay (Washington State, USA) has been 1 of the rare intertidal locations where large-scale pesticide applications occur. Until recently, carbaryl was applied to control burrowing shrimp that decrease commercial oyster productivity. The bay is a critical habitat for green sturgeon (Acipenser medirostris), an anadromous species listed as threatened under the US Endangered Species Act. However, the hazard that carbaryl poses is unknown. Surrogate seawater-acclimated white sturgeon (A. transmontanus) were exposed to 0 μg L(-1) , 30 μg L(-1) , 100 μg L(-1) , 300 μg L(-1) , 1000 μg L(-1) , and 3000 μg L(-1) carbaryl for 6 h, and brain acetylcholinesterase (AChE) and plasma butyrylcholinesterase (BChE) activities were measured. Enzyme recovery was measured in an additional cohort exposed to 1000 μg L(-1) carbaryl for 6 h. Activity of AChE was reduced (p ≤ 0.001) at concentrations ≥ 100 μg L(-1) with recovery in the 1000 μg L(-1) cohort by 72 h. Surprisingly, BChE activity was greater than controls at concentrations ≥ 300 μg L(-1) (p > 0.05), a finding confirmed in additional fish exposed to 3000 μg L(-1) for 6 h (+30%, p < 0.001) with apparent recovery by 48 h. Plasma samples were collected from free-living green sturgeon before and 4 d to 5 d after application of carbaryl in Willapa Bay. Activity of BChE after application was reduced 28% (p < 0.001), indicating exposure to the pesticide. However, the lack of congruence between BChE and AChE activity in captive white sturgeon exposed to carbaryl indicates that further studies are needed to better understand the risk carbaryl exposure poses to green sturgeon. Environ Toxicol Chem 2016;35:2003-2015. © 2015 SETAC. PMID:26678014

  4. Investigation of Remote-Phosphor White Light-Emitting Diodes with Multi-Phosphor Layers

    NASA Astrophysics Data System (ADS)

    Zhu, Yiting; Narendran, Nadarajah

    2010-10-01

    To understand how multiple phosphors in a mixture or stacked layers affect the performance of the remote-phosphor “scattered photon extraction (SPE)” white light-emitting diode (LED), a laboratory study was conducted with commercial yellow [quantum efficiency (QE)=0.91] and red (QE=0.59) phosphors in equal amounts. The highest light output was obtained when the longer-wavelength red phosphor was placed as the second layer. Experiments showed that when using two phosphors in an SPE package, several factors influence the performance: mixture or stacked layers; specific layer order; phosphor densities; phosphor external QE; overall spectral power distribution (SPD); phosphor excitation and emission spectra and efficiencies.

  5. Seasonal Distribution and Movements of Atlantic and Shortnose Sturgeon in the Penobscot River Estuary, Maine

    USGS Publications Warehouse

    Zydlewski, Joseph; Fernandes, Stephen J.; Zydlewski, Gayle B.; Wippelhauser, Gail S.; Kinnison, Michael T.

    2016-01-01

    Relatively little is known about the distribution and seasonal movement patterns of shortnose sturgeon Acipenser brevirostrum and Atlantic sturgeon Acipenser oxyrinchus oxyrinchus occupying rivers in the northern part of their range. During 2006 and 2007, 40 shortnose sturgeon (66–113.4 cm fork length [FL]) and 8 Atlantic sturgeon (76.2–166.2 cm FL) were captured in the Penobscot River, Maine, implanted with acoustic transmitters, and monitored using an array of acoustic receivers in the Penobscot River estuary and Penobscot Bay. Shortnose sturgeon were present year round in the estuary and overwintered from fall (mid-October) to spring (mid-April) in the upper estuary. In early spring, all individuals moved downstream to the middle estuary. Over the course of the summer, many individuals moved upstream to approximately 2 km of the downstream-most dam (46 river kilometers [rkm] from the Penobscot River mouth [rkm 0]) by August. Most aggregated into an overwintering site (rkm 36.5) in mid- to late fall. As many as 50% of the tagged shortnose sturgeon moved into and out of the Penobscot River system during 2007, and 83% were subsequently detected by an acoustic array in the Kennebec River, located 150 km from the Penobscot River estuary. Atlantic sturgeon moved into the estuary from the ocean in the summer and concentrated into a 1.5-km reach. All Atlantic sturgeon moved to the ocean by fall, and two of these were detected in the Kennebec River. Although these behaviors are common for Atlantic sturgeon, regular coastal migrations of shortnose sturgeon have not been documented previously in this region. These results have important implications for future dam removals as well as for rangewide and river-specific shortnose sturgeon management.

  6. Volume properties and spectroscopy: A terahertz Raman investigation of hen egg white lysozyme

    NASA Astrophysics Data System (ADS)

    Sassi, Paola; Perticaroli, Stefania; Comez, Lucia; Giugliarelli, Alessandra; Paolantoni, Marco; Fioretto, Daniele; Morresi, Assunta

    2013-12-01

    The low frequency depolarized Raman spectra of 100 mg/ml aqueous solutions of hen egg white lysozyme (HEWL) have been collected in the 25-85 °C range. Short and long exposures to high temperatures have been used to modulate the competition between the thermally induced reversible and irreversible denaturation processes. A peculiar temperature evolution of spectra is evidenced under prolonged exposure of the protein solution at temperatures higher than 65 °C. This result is connected to the self-assembling of polypeptide chains and testifies the sensitivity of the technique to the properties of both protein molecule and its surrounding. Solvent free spectra have been obtained after subtraction of elastic and solvent components and assigned to a genuine vibrational contribution of hydrated HEWL. A straight similarity is observed between the solvent-free THz Raman feature and the vibrational density of states as obtained by molecular dynamics simulations; according to this, we verify the relation between this spectroscopic observable and the effective protein volume, and distinguish the properties of this latter respect to those of the hydration shell in the pre-melting region.

  7. Acute toxicity of ammonia and nitrite to shortnose sturgeon fingerlings

    USGS Publications Warehouse

    Fontenot, Q.C.; Isely, J.J.; Tomasso, J.R.

    1998-01-01

    The 96-h median-lethal concentration (96-h LC50) of total ammonia nitrogen (ammonia-N) to fingerling shortnose sturgeon Acipenser brevirostrum was 149.8 ?? 55.20 mg/L (mean ?? SD, 17.9 ?? 0.62??C, pH = 6.8-7.3). Calculated 96-h LC50 for un-ionized ammonia-N was 0.58 ?? 0.213 mg/L. The 96-h LC50 of nitrite nitrogen to shortnose sturgeon fingerlings was 11.3 ?? 8.17 mg/L (17.9 ?? 0.31??C, <1.0 mg chloride/L, <1.0 mg magnesium/L, 1.8 mg calcium/L, 7.7 mg sodium/L).

  8. Novel single-nucleotide polymorphism markers confirm successful spawning of endangered pallid sturgeon in the upper Missouri River Basin

    USGS Publications Warehouse

    Eichelberger, Jennifer S.; Braaten, P. J.; Fuller, D. B.; Krampe, Matthew S.; Heist, Edward J.

    2014-01-01

    Spawning of the federally endangered Pallid Sturgeon Scaphirhynchus albus is known to occur in the upper Missouri River basin, but progeny from natural reproductive events have not been observed and recruitment to juvenile or adult life stages has not been documented in recent decades. Identification of Pallid Sturgeon progeny is confounded by the fact that Shovelnose Sturgeon S. platorynchus occurs throughout the entire range of Pallid Sturgeon and the two species are essentially indistinguishable (morphometrically and meristically) during early life stages. Moreover, free embryos of sympatric Paddlefish Polyodon spathula are very similar to the two sturgeon species. In this study, three single-nucleotide polymorphism (SNP) assays were employed to screen acipenseriform free embryos and larvae collected from the upper Missouri River basin in 2011, 2012, and 2013. A mitochondrial DNA SNP discriminates Paddlefish from sturgeon, and specific multilocus genotypes at two nuclear DNA SNPs occurred in 98.9% of wild adult Pallid Sturgeon but only in 3% of Shovelnose Sturgeon sampled in the upper Missouri River. Individuals identified as potential Pallid Sturgeon based on SNP genotypes were further analyzed at 19 microsatellite loci for species discrimination. Out of 1,423 free embryos collected over 3 years of sampling, 971 Paddlefish, 446 Shovelnose Sturgeon, and 6 Pallid Sturgeon were identified. Additionally, 249 Scaphirhynchus spp. benthic larvae were screened, but no Pallid Sturgeon were detected. These SNP markers provide an efficient method of screening acipenseriform early life stages for the presence of Pallid Sturgeon in the Missouri River basin. Detection of wild Pallid Sturgeon free embryos in the upper Missouri and Yellowstone rivers supports the hypothesis that the failure of wild Pallid Sturgeon to recruit to the juvenile life stage in the upper Missouri River basin is caused by early life stage mortality rather than by lack of successful spawning.

  9. 78 FR 46813 - Safety Zone; Evening on the Bay Fireworks; Sturgeon Bay, WI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-02

    ... Department of Homeland Security FR Federal Register NPRM Notice of Proposed Rulemaking TFR Temporary Final... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Evening on the Bay Fireworks; Sturgeon Bay... of Sturgeon Bay due to a fireworks display. This temporary safety zone is necessary to protect...

  10. Gulf sturgeon spawning migration and habitat in the Choctawhatchee River system, Alabama-Florida

    USGS Publications Warehouse

    Fox, D.A.; Hightower, J.E.; Parauka, F.M.

    2000-01-01

    Information about spawning migration and spawning habitat is essential to maintain and ultimately restore populations of endangered and threatened species of anadromous fish. We used ultrasonic and radiotelemetry to monitor the movements of 35 adult Gulf sturgeon Acipenser oxyrinchus desotoi (a subspecies of the Atlantic sturgeon A. oxyrinchus) as they moved between Choctawhatchee Bay and the Choctawhatchee River system during the spring of 1996 and 1997. Histological analysis of gonadal biopsies was used to determine the sex and reproductive status of individuals. Telemetry results and egg sampling were used to identify Gulf sturgeon spawning sites and to examine the roles that sex and reproductive status play in migratory behavior. Fertilized Gulf sturgeon eggs were collected in six locations in both the upper Choctawhatchee and Pea rivers. Hard bottom substrate, steep banks, and relatively high flows characterized collection sites. Ripe Gulf sturgeon occupied these spawning areas from late March through early May, which included the interval when Gulf sturgeon eggs were collected. For both sexes, ripe fish entered the Choctawhatchee River significantly earlier and at a lower water temperature and migrated further upstream than did nonripe fish. Males entered the Choctawhatchee River at a lower water temperature than females. Results from histology and telemetry support the hypothesis that male Gulf sturgeon may spawn annually, whereas females require more than 1 year between spawning events. Upper river hard bottom areas appear important for the successful spawning of Gulf sturgeon, and care should be taken to protect against habitat loss or degradation of known spawning habitat.

  11. A Conceptual Life-History Model for Pallid and Shovelnose Sturgeon

    USGS Publications Warehouse

    Wildhaber, Mark L.; DeLonay, Aaron J.; Papoulias, Diana M.; Galat, David L.; Jacobson, Robert B.; Simpkins, Darin G.; Braaten, P. J.; Korschgen, Carl E.; Mac, Michael J.

    2007-01-01

    Intensive management of the Missouri and Mississippi Rivers has resulted in dramatic physical changes to these rivers. These changes have been implicated as causative agents in the decline of pallid sturgeon. The pallid sturgeon, federally listed as endangered, is endemic to the turbid waters of the Missouri River and the Lower Mississippi River. The sympatric shovelnose sturgeon historically was more common and widespread than the pallid sturgeon. Habitat alteration, river regulation, pollution, and over-harvest have resulted in the now predictable patterns of decline and localized extirpation of sturgeon across species and geographic areas. Symptomatic of this generalized pattern of decline is poor reproductive success, and low or no recruitment of wild juveniles to the adult population. The purpose of this report is to introduce a conceptual life-history model of the factors that affect reproduction, growth, and survival of shovelnose and pallid sturgeons. The conceptual model provided here was developed to organize the understanding about the complex life history of Scaphirhynchus sturgeons. It was designed to be used for communication, planning, and to provide the structure for a population-forecasting model. These models are intended to be dynamic and responsive to new information and changes in river management, thereby providing scientists, stakeholders, and managers with ways to improve understanding of the effects of management actions on the ecological requirements of Scaphirhynchus sturgeons. As new scientific knowledge becomes available, it could be included in the model in many ways at various integration levels.

  12. Ecological requirements for pallid sturgeon reproduction and recruitment in the Lower Missouri River: Annual report 2009

    USGS Publications Warehouse

    DeLonay, Aaron J.; Jacobson, Robert B.; Papoulias, Diana M.; Wildhaber, Mark L.; Chojnacki, Kimberly A.; Pherigo, Emily K.; Bergthold, Casey L.; Mestl, Gerald E.

    2010-01-01

    The Comprehensive Sturgeon Research Project is a multiyear, multiagency collaborative research framework developed to provide information to support pallid sturgeon recovery and Missouri River management decisions. The general Comprehensive Sturgeon Research Project strategy is to integrate field and laboratory studies of sturgeon reproductive ecology, habitat requirements, and physiology to produce a predictive understanding of sturgeon population dynamics. The project scope of work is developed annually with cooperating research partners and in collaboration with the U.S. Army Corps of Engineers, Missouri River Recovery-Integrated Science Program. The research consists of several interdependent and complementary research tasks engaging multiple disciplines that primarily address spawning as a probable limiting factor in reproduction and survival of the pallid sturgeon. The research is multifaceted and is designed to provide information needed for management decisions impacting habitat restoration, flow modification, and pallid sturgeon population augmentation on the Missouri River, and throughout the range of the species. Research activities and progress towards understanding of the species are reported to the U.S. Army Corps of Engineers annually. This annual report details the research effort and progress made by Comprehensive Sturgeon Research Project during 2009.

  13. Diel activity of Gulf of Mexico sturgeon in a northwest Florida bay

    USGS Publications Warehouse

    Wrege, B.M.; Duncan, M.S.; Isely, J.J.

    2011-01-01

    In this paper, we assess patterns in activity of Gulf of Mexico sturgeon Acipenser oxyrinchus desotoi over a 24-h period in the Pensacola bay system, Florida. Although seasonal migration of sturgeon is well documented, little information is available pertaining to daily variation in activity. We surgically implanted 58 Gulf sturgeon with acoustic transmitters in the Escambia (n=26), Yellow (n=8), Blackwater (n=12) and Choctawhatchee rivers (n=12) in June, July, September and October 2005. Gulf sturgeon location was monitored using an array of 56 fixed-station acoustic receivers. The relationship between frequency of Gulf sturgeon observations recorded on all acoustic receivers and time of day for all seasons combined indicated a strong diel activity pattern. Gulf sturgeon were frequently detected at night in all seasons with the exception of summer. Consecutive hourly observations indicated lateral movement of Gulf sturgeon between independent acoustic receivers on 15% of all observations of individuals. The use of an acoustic receiver array not only provides continuous data within a defined area, but also provides insight into nocturnal behavior of Gulf sturgeon not previously identified. ?? 2011 Blackwell Verlag, Berlin.

  14. Characterization and inhibition of nitrite uptake in shortnose sturgeon fingerlings

    USGS Publications Warehouse

    Fontenot, Q.C.; Isely, J.J.; Tomasso, J.R.

    1999-01-01

    Efforts are underway to culture the endangered shortnose sturgeon Acipenser brevirostrum for possible reintroduction. As part of a larger project to develop culture techniques for this species, the uptake of nitrite was evaluated in fingerlings (16.5 ?? 4.85 g; mean ?? SD). Plasma nitrite concentrations increased significantly with exposure time (0-5 d) and dose (0-4 mg nitrite-N/L). Shortnose sturgeon fingerlings were able to concentrate nitrite in their plasma to more than 63 times the environmental concentration. Chloride, as either sodium chloride or calcium chloride, partially inhibited nitrite uptake. However, calcium chloride was a better inhibitor. After previous exposure (2 d at 2.13 ?? 0.080 mg nitrite-N/L) plasma nitrite-N decreased from 165.5 to 36.7 mg/L during a 3-d simultaneous exposure to 2.13 ?? 0.080 mg nitrite-N/L and treatment with 40 mg chloride/L as calcium chloride. The addition of calcium chloride to the water appeared to be an effective means of preventing nitrite uptake and treating nitrite toxicity in hatchery-reared shortnose sturgeon fingerlings.

  15. Importance of environmental endocrinology in fisheries management and aquaculture of sturgeons.

    PubMed

    Webb, Molly A H; Doroshov, S I

    2011-01-15

    Less is known about the reproductive endocrinology of sturgeons compared to modern teleosts. However, tools to assess the reproductive endocrinology and effects of environmental factors on reproduction do exist. This review utilizes case studies to describe the parameters involved in environmental endocrinology and the management and recovery efforts for the phylogenetically ancient sturgeon and paddlefish (Clade Chondrostei). Specifically, we discuss the use of environmental endocrinology to determine sex and stage of maturity and identify oviposition on spawning grounds, the importance of understanding endocrine disruption pathways, the challenges and benefits of assessing stress in wild populations of sturgeon, and three major physiological events in the reproductive development of farmed sturgeon understanding of which appears to be crucial for improving sturgeon aquaculture.

  16. Food Utilization (Energy-Flow) Investigations with Pieris Brassicae (Large White) Caterpillars.

    ERIC Educational Resources Information Center

    Jones, Derek H. T.

    1985-01-01

    Background information, procedures used, and typical results obtained are provided for experiments in which caterpillars are used to investigate energy-flow relationships. Areas in which the experiments could be used include ecology, applied biology, and animal feeding. (DH)

  17. White Oak Creek watershed: Melton Valley area Remedial Investigation report, at the Oak Ridge National Laboratory, Oak Ridge, Tennessee: Volume 2, Appendixes A and B

    SciTech Connect

    1996-11-01

    This document contains Appendixes A ``Source Inventory Information for the Subbasins Evaluated for the White Oak Creek Watershed`` and B ``Human Health Risk Assessment for White Oak Creek / Melton Valley Area`` for the remedial investigation report for the White Oak Creek Watershed and Melton Valley Area. Appendix A identifies the waste types and contaminants for each subbasin in addition to the disposal methods. Appendix B identifies potential human health risks and hazards that may result from contaminants present in the different media within Oak Ridge National Laboratory sites.

  18. Atlantic Sturgeon Spatial and Temporal Distribution in Minas Passage, Nova Scotia, Canada, a Region of Future Tidal Energy Extraction.

    PubMed

    Stokesbury, Michael J W; Logan-Chesney, Laura M; McLean, Montana F; Buhariwalla, Colin F; Redden, Anna M; Beardsall, Jeffrey W; Broome, Jeremy E; Dadswell, Michael J

    2016-01-01

    In the Bay of Fundy, Atlantic sturgeon from endangered and threatened populations in the USA and Canada migrate through Minas Passage to enter and leave Minas Basin. A total of 132 sub-adult and adult Atlantic sturgeon were tagged in Minas Basin during the summers of 2010-2014 using pressure measuring, uniquely coded, acoustic transmitters with a four or eight year life span. The aim of this study was to examine spatial and seasonal distribution of sturgeon in Minas Passage during 2010-2014 and test the hypothesis that, when present, Atlantic sturgeon were evenly distributed from north to south across Minas Passage. This information is important as tidal energy extraction using in-stream, hydrokinetic turbines is planned for only the northern portion of Minas Passage. Electronic tracking data from a total of 740 sturgeon days over four years demonstrated that Atlantic sturgeon used the southern portion of Minas Passage significantly more than the northern portion. Sturgeon moved through Minas Passage at depths mostly between 15 and 45 m (n = 10,116; mean = 31.47 m; SD = 14.88). Sturgeon mean swimming depth was not significantly related to bottom depth and in deeper regions they swam pelagically. Sturgeon predominately migrated inward through Minas Passage during spring, and outward during late summer-autumn. Sturgeon were not observed in Minas Passage during winter 2012-2013 when monitoring receivers were present. This information will enable the estimation of encounters of Atlantic sturgeon with in-stream hydrokinetic turbines.

  19. Atlantic Sturgeon Spatial and Temporal Distribution in Minas Passage, Nova Scotia, Canada, a Region of Future Tidal Energy Extraction

    PubMed Central

    Stokesbury, Michael J. W.; Logan-Chesney, Laura M.; McLean, Montana F.; Buhariwalla, Colin F.; Redden, Anna M.; Beardsall, Jeffrey W.; Broome, Jeremy E.; Dadswell, Michael J.

    2016-01-01

    In the Bay of Fundy, Atlantic sturgeon from endangered and threatened populations in the USA and Canada migrate through Minas Passage to enter and leave Minas Basin. A total of 132 sub-adult and adult Atlantic sturgeon were tagged in Minas Basin during the summers of 2010–2014 using pressure measuring, uniquely coded, acoustic transmitters with a four or eight year life span. The aim of this study was to examine spatial and seasonal distribution of sturgeon in Minas Passage during 2010–2014 and test the hypothesis that, when present, Atlantic sturgeon were evenly distributed from north to south across Minas Passage. This information is important as tidal energy extraction using in-stream, hydrokinetic turbines is planned for only the northern portion of Minas Passage. Electronic tracking data from a total of 740 sturgeon days over four years demonstrated that Atlantic sturgeon used the southern portion of Minas Passage significantly more than the northern portion. Sturgeon moved through Minas Passage at depths mostly between 15 and 45 m (n = 10,116; mean = 31.47 m; SD = 14.88). Sturgeon mean swimming depth was not significantly related to bottom depth and in deeper regions they swam pelagically. Sturgeon predominately migrated inward through Minas Passage during spring, and outward during late summer-autumn. Sturgeon were not observed in Minas Passage during winter 2012–2013 when monitoring receivers were present. This information will enable the estimation of encounters of Atlantic sturgeon with in-stream hydrokinetic turbines. PMID:27383274

  20. Atlantic Sturgeon Spatial and Temporal Distribution in Minas Passage, Nova Scotia, Canada, a Region of Future Tidal Energy Extraction.

    PubMed

    Stokesbury, Michael J W; Logan-Chesney, Laura M; McLean, Montana F; Buhariwalla, Colin F; Redden, Anna M; Beardsall, Jeffrey W; Broome, Jeremy E; Dadswell, Michael J

    2016-01-01

    In the Bay of Fundy, Atlantic sturgeon from endangered and threatened populations in the USA and Canada migrate through Minas Passage to enter and leave Minas Basin. A total of 132 sub-adult and adult Atlantic sturgeon were tagged in Minas Basin during the summers of 2010-2014 using pressure measuring, uniquely coded, acoustic transmitters with a four or eight year life span. The aim of this study was to examine spatial and seasonal distribution of sturgeon in Minas Passage during 2010-2014 and test the hypothesis that, when present, Atlantic sturgeon were evenly distributed from north to south across Minas Passage. This information is important as tidal energy extraction using in-stream, hydrokinetic turbines is planned for only the northern portion of Minas Passage. Electronic tracking data from a total of 740 sturgeon days over four years demonstrated that Atlantic sturgeon used the southern portion of Minas Passage significantly more than the northern portion. Sturgeon moved through Minas Passage at depths mostly between 15 and 45 m (n = 10,116; mean = 31.47 m; SD = 14.88). Sturgeon mean swimming depth was not significantly related to bottom depth and in deeper regions they swam pelagically. Sturgeon predominately migrated inward through Minas Passage during spring, and outward during late summer-autumn. Sturgeon were not observed in Minas Passage during winter 2012-2013 when monitoring receivers were present. This information will enable the estimation of encounters of Atlantic sturgeon with in-stream hydrokinetic turbines. PMID:27383274

  1. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (Mid-Atlantic Bight): Atlantic and shortnosed sturgeons

    SciTech Connect

    Gilbert, C.R. )

    1989-12-01

    Species profiles are literature summaries of the taxonomy, morphology, range, life history, and environmental requirements of coastal species. The Atlantic and shortnose sturgeons (especially the former) were commercially important fishes between 1880 and 1900, but stocks have since decreased markedly and the shortnose sturgeon is now classified as federally endangered. Although the two species are anadromous, the shortnose sturgeon tends to spawn farther upstream, and spawning in both species usually occurs over a clean, hard substrate washed by a moderate to strong current. The shortnose sturgeon usually spawn earlier at the same latitude, with spawning of this species in the St. John River, New Brunswick, being completed by mid-May, as opposed to late June or even July for the Atlantic sturgeon. During non-spawning periods, the shortnose is largely confined to estuaries and apparently does not undergo the extensive coastal migrations that are characteristic of the Atlantic sturgeon. Atlantic sturgeon mature more slowly than shortnose sturgeon at comparable latitudes, with male and female Atlantic sturgeon from the Hudson River, New York, requiring at least 11 and 18 years, respectively, to reach maturity, compared with less than half that time for the shortnose sturgeon. Spawning in both sexes may occur thereafter only once every several years. Both species are usually indiscriminate feeders and feed by sucking materials off the bottom with their protrusible mouths. Feeding apparently occurs mostly at night in the shortnose sturgeon. 71 refs., 14 figs., 1 tab.

  2. Antioxidant and cryoprotective effects of Amur sturgeon skin gelatin hydrolysate in unwashed fish mince.

    PubMed

    Nikoo, Mehdi; Benjakul, Soottawat; Xu, Xueming

    2015-08-15

    Antioxidant and cryoprotective effects of Amur sturgeon skin gelatin hydrolysates prepared using different commercial proteases in unwashed fish mince were investigated. Gelatin hydrolysates prepared using either Alcalase or Flavourzyme, were effective in preventing lipid oxidation as evidenced by the lower thiobarbituric acid-reactive substances formation. Gelatin hydrolysates were able to retard protein oxidation as indicated by the retarded protein carbonyl formation and lower loss in sulfhydryl content. In the presence of gelatin hydrolysates, unwashed mince had higher transition temperature of myosin and higher enthalpy of myosin and actin as determined by differential scanning calorimetry. Based on low field proton nuclear magnetic resonance analysis, gelatin hydrolysates prevented the displacement of water molecules between the different compartments, thus stabilizing the water associated with myofibrils in unwashed mince induced by repeated freeze-thawing. Oligopeptides in gelatin hydrolysates more likely contributed to the cryoprotective effect. Thus, gelatin hydrolysate could act as both antioxidant and cryoprotectant in unwashed fish mince.

  3. Preparing Culturally Responsive Literacy Teachers: Investigations of Whiteness in a Literacy Methods Course

    ERIC Educational Resources Information Center

    Royster, Kelly Berghoff

    2013-01-01

    Teacher education programs across the United States must prepare teachers who have the content area knowledge, pedagogical expertise, and cultural competence needed to teach an increasingly diverse student population. One consistent suggestion for programs committed to preparing culturally responsive teachers is to incorporate investigations of…

  4. Gonadotropins in the Russian Sturgeon: Their Role in Steroid Secretion and the Effect of Hormonal Treatment on Their Secretion.

    PubMed

    Yom-Din, Svetlana; Hollander-Cohen, Lian; Aizen, Joseph; Boehm, Benjamin; Shpilman, Michal; Golan, Matan; Hurvitz, Avshalom; Degani, Gad; Levavi-Sivan, Berta

    2016-01-01

    In the reproduction process of male and female fish, pituitary derived gonadotropins (GTHs) play a key role. To be able to specifically investigate certain functions of Luteinizing (LH) and Follicle stimulating hormone (FSH) in Russian sturgeon (Acipenser gueldenstaedtii; st), we produced recombinant variants of the hormones using the yeast Pichia pastoris as a protein production system. We accomplished to create in vitro biologically active heterodimeric glycoproteins consisting of two associated α- and β-subunits in sufficient quantities. Three dimensional modelling of both GTHs was conducted in order to study the differences between the two GTHs. Antibodies were produced against the unique β-subunit of each of the GTHs, in order to be used for immunohistochemical analysis and to develop an ELISA for blood and pituitary hormone quantification. This detection technique revealed the specific localization of the LH and FSH cells in the sturgeon pituitary and pointed out that both cell types are present in substantially higher numbers in mature males and females, compared to immature fish. With the newly attained option to prevent cross-contamination when investigating on the effects of GTH administration, we compared the steroidogeneic response (estradiol and 11-Keto testosterone (11-KT) in female and males, respectively) of recombinant stLH, stFSH, and carp pituitary extract in male and female sturgeon gonads at different developmental stages. Finally, we injected commercially available gonadotropin releasing hormones analog (GnRH) to mature females, and found a moderate effect on the development of ovarian follicles. Application of only testosterone (T) resulted in a significant increase in circulating levels of 11-KT whereas the combination of GnRH + T did not affect steroid levels at all. The response pattern for estradiol demonstrated a similar situation. FSH levels showed significant increases when GnRH + T was administered, while no changes were present in

  5. Gonadotropins in the Russian Sturgeon: Their Role in Steroid Secretion and the Effect of Hormonal Treatment on Their Secretion

    PubMed Central

    Yom-Din, Svetlana; Hollander-Cohen, Lian; Aizen, Joseph; Boehm, Benjamin; Shpilman, Michal; Golan, Matan; Hurvitz, Avshalom; Degani, Gad; Levavi-Sivan, Berta

    2016-01-01

    In the reproduction process of male and female fish, pituitary derived gonadotropins (GTHs) play a key role. To be able to specifically investigate certain functions of Luteinizing (LH) and Follicle stimulating hormone (FSH) in Russian sturgeon (Acipenser gueldenstaedtii; st), we produced recombinant variants of the hormones using the yeast Pichia pastoris as a protein production system. We accomplished to create in vitro biologically active heterodimeric glycoproteins consisting of two associated α- and β-subunits in sufficient quantities. Three dimensional modelling of both GTHs was conducted in order to study the differences between the two GTHs. Antibodies were produced against the unique β-subunit of each of the GTHs, in order to be used for immunohistochemical analysis and to develop an ELISA for blood and pituitary hormone quantification. This detection technique revealed the specific localization of the LH and FSH cells in the sturgeon pituitary and pointed out that both cell types are present in substantially higher numbers in mature males and females, compared to immature fish. With the newly attained option to prevent cross-contamination when investigating on the effects of GTH administration, we compared the steroidogeneic response (estradiol and 11-Keto testosterone (11-KT) in female and males, respectively) of recombinant stLH, stFSH, and carp pituitary extract in male and female sturgeon gonads at different developmental stages. Finally, we injected commercially available gonadotropin releasing hormones analog (GnRH) to mature females, and found a moderate effect on the development of ovarian follicles. Application of only testosterone (T) resulted in a significant increase in circulating levels of 11-KT whereas the combination of GnRH + T did not affect steroid levels at all. The response pattern for estradiol demonstrated a similar situation. FSH levels showed significant increases when GnRH + T was administered, while no changes were present in

  6. Gonadotropins in the Russian Sturgeon: Their Role in Steroid Secretion and the Effect of Hormonal Treatment on Their Secretion.

    PubMed

    Yom-Din, Svetlana; Hollander-Cohen, Lian; Aizen, Joseph; Boehm, Benjamin; Shpilman, Michal; Golan, Matan; Hurvitz, Avshalom; Degani, Gad; Levavi-Sivan, Berta

    2016-01-01

    In the reproduction process of male and female fish, pituitary derived gonadotropins (GTHs) play a key role. To be able to specifically investigate certain functions of Luteinizing (LH) and Follicle stimulating hormone (FSH) in Russian sturgeon (Acipenser gueldenstaedtii; st), we produced recombinant variants of the hormones using the yeast Pichia pastoris as a protein production system. We accomplished to create in vitro biologically active heterodimeric glycoproteins consisting of two associated α- and β-subunits in sufficient quantities. Three dimensional modelling of both GTHs was conducted in order to study the differences between the two GTHs. Antibodies were produced against the unique β-subunit of each of the GTHs, in order to be used for immunohistochemical analysis and to develop an ELISA for blood and pituitary hormone quantification. This detection technique revealed the specific localization of the LH and FSH cells in the sturgeon pituitary and pointed out that both cell types are present in substantially higher numbers in mature males and females, compared to immature fish. With the newly attained option to prevent cross-contamination when investigating on the effects of GTH administration, we compared the steroidogeneic response (estradiol and 11-Keto testosterone (11-KT) in female and males, respectively) of recombinant stLH, stFSH, and carp pituitary extract in male and female sturgeon gonads at different developmental stages. Finally, we injected commercially available gonadotropin releasing hormones analog (GnRH) to mature females, and found a moderate effect on the development of ovarian follicles. Application of only testosterone (T) resulted in a significant increase in circulating levels of 11-KT whereas the combination of GnRH + T did not affect steroid levels at all. The response pattern for estradiol demonstrated a similar situation. FSH levels showed significant increases when GnRH + T was administered, while no changes were present in

  7. Effects of Dietary Garlic Extract on Growth, Feed Utilization and Whole Body Composition of Juvenile Sterlet Sturgeon (Acipenser ruthenus)

    PubMed Central

    Lee, Dong-Hoon; Ra, Chang-Six; Song, Young-Han; Sung, Kyung-Il; Kim, Jeong-Dae

    2012-01-01

    This study was carried out to investigate the supplemental effects of dietary garlic extract (GE) on growth performance of juvenile sterlet sturgeon (Acipenser ruthenus). The first experiment was designed to determine the optimum levels of garlic extract as growth promoter during 10 weeks. Three groups (two replicates/group) of 240 fish with mean body weight of 85 g were fed with diets containing 0 (control), 0.5 and 1.0% of GE. The highest weight gain (%) and feed efficiency (%) were found in fish groups fed with diet containing 0.5% GE. Subsequently, the supplemental effects of dietary GE was studied on growth of juvenile sterlet sturgeon (Acipenser ruthenus) with an average body weight of 59.6 g. Fish cultured in freshwater were randomly allotted to each of 10 tanks (two groups of five replicates, 20 fish/tank) and fed diets with 0.5% GE or without GE (control), respectively, at the level of 2.0% of fish body weight per day for 5 weeks. Weight gain (51.1%), feed efficiency (79.1%), specific growth rate (1.18%) and protein efficiency ratio (1.50) of fish fed 0.5% GE were significantly (p<0.05) higher than those fish fed the control diet. Significantly higher protein (PRE 20.4%) and lipid retention efficiencies (LRE, 74.5%) were also found in 0.5% GE group (p<0.05). The present results suggested that dietary GE could improve growth and feed utilization of juvenile sterlet sturgeons. PMID:25049599

  8. Effects of Dietary Garlic Powder on Growth, Feed Utilization and Whole Body Composition Changes in Fingerling Sterlet Sturgeon, Acipenser ruthenus

    PubMed Central

    Lee, Dong-Hoon; Lim, Seong-Ryul; Han, Jung-Jo; Lee, Sang-Woo; Ra, Chang-Six; Kim, Jeong-Dae

    2014-01-01

    A 12 week growth study was carried out to investigate the supplemental effects of dietary garlic powder (GP) on growth, feed utilization and whole body composition changes of fingerling sterlet sturgeon Acipenser ruthenus (averaging weight, 5.5 g). Following a 24-h fasting, 540 fish were randomly distributed to each of 18 tanks (30 fish/tank) under a semi-recirculation freshwater system. The GP of 0.5% (GP0.5), 1% (GP1), 1.5% (GP1.5), 2% (GP2) and 3% (GP3) was added to the control diet (GP0) containing 43% protein and 16% lipid. After the feeding trial, weight gain (WG) of fish fed GP1.5, GP2 and GP3 were significantly higher (p<0.05) than those of fish fed GP0, GP0.5 and GP1. Feed efficiency and specific growth rate (SGR) showed a similar trend to WG. Protein efficiency ratio of fish fed GP1.5, GP2, and GP3 were significantly higher (p<0.05) than those of fish groups fed the other diets. A significant difference (p<0.05) was found in whole body composition (moisture, crude protein, crude lipid, ash, and fiber) of fish at the end of the experiment. Significantly higher (p<0.05) protein and lipid retention efficiencies (PRE and LRE) were also found in GP1.5, GP2, and GP3 groups. Broken-line regression model analysis and second order polynomial regression model analysis relation on the basis of SGR and WG indicated that the dietary optimal GP level could be greater than 1.77% and 1.79%, but less than 2.95% and 3.18% in fingerling sterlet sturgeon. The present study suggested that dietary GP for fingerling sterlet sturgeon could positively affect growth performance and protein retention. PMID:25178374

  9. Paleomagnetism and paleointensity of Mid-Continental Rift System basalts at Silver Mountain and Sturgeon River Falls (Upper Michigan)

    NASA Astrophysics Data System (ADS)

    Kulakov, E.; Piispa, E. J.; Laird, M. S.; Smirnov, A. V.; Diehl, J. F.

    2009-12-01

    Paleomagnetic and paleointensity data from Precambrian rocks are of great importance for understanding the early geodynamo and tectonic evolution of the Earth. We will present results from a rock magnetic and paleomagnetic investigation of basaltic lava flow sequences at Silver Mountain and Sturgeon River Falls in Upper Michigan. While the Silver Mountain and Sturgeon River Falls lava flows have not been radiometrically dated, these rocks have been assigned to the Siemens Creek Volcanics, the lowermost member of ~1.1 Ga Powder Mill Group (PMG). The PMG represents one of the oldest volcanic units associated with the Mid-Continental Rift System (MCRS). We sampled 13 lava flows from the Silver Mountain and two lava flows from the Sturgeon River Falls exposures (a minimum of 15 cores per flow were taken). Paleomagnetic directions were determined from detailed thermal and/or alternating field demagnetization preceded by an initial low-temperature (liquid nitrogen) demagnetization. Most specimens revealed a single- or a two-component remanent magnetization. At both locations, the characteristic remanent magnetization (ChRM) has a reversed direction with very steep inclination similar to that found in other rocks representing the early stages of MCRS. Our magnetic hysteresis measurements, unblocking temperature spectra, and scanning electron microscopy analyses suggest low-Ti, pseudosingle-domain titanomagnetite as the principal magnetic carrier in these rocks. For paleointensity determinations, we applied the multispecimen parallel differential pTRM method. These data add to the Precambrian paleointensity database which otherwise remains limited because of alteration and other factors hampering the applicability of conventional Thellier double-heating method.

  10. Unscreened water-diversion pipes pose an entrainment risk to the threatened green sturgeon, Acipenser medirostris.

    PubMed

    Mussen, Timothy D; Cocherell, Dennis; Poletto, Jamilynn B; Reardon, Jon S; Hockett, Zachary; Ercan, Ali; Bandeh, Hossein; Kavvas, M Levent; Cech, Joseph J; Fangue, Nann A

    2014-01-01

    Over 3,300 unscreened agricultural water diversion pipes line the levees and riverbanks of the Sacramento River (California) watershed, where the threatened Southern Distinct Population Segment of green sturgeon, Acipenser medirostris, spawn. The number of sturgeon drawn into (entrained) and killed by these pipes is greatly unknown. We examined avoidance behaviors and entrainment susceptibility of juvenile green sturgeon (35±0.6 cm mean fork length) to entrainment in a large (>500-kl) outdoor flume with a 0.46-m-diameter water-diversion pipe. Fish entrainment was generally high (range: 26-61%), likely due to a lack of avoidance behavior prior to entering inescapable inflow conditions. We estimated that up to 52% of green sturgeon could be entrained after passing within 1.5 m of an active water-diversion pipe three times. These data suggest that green sturgeon are vulnerable to unscreened water-diversion pipes, and that additional research is needed to determine the potential impacts of entrainment mortality on declining sturgeon populations. Data under various hydraulic conditions also suggest that entrainment-related mortality could be decreased by extracting water at lower diversion rates over longer periods of time, balancing agricultural needs with green sturgeon conservation. PMID:24454967

  11. Habitat use and selection by adult pallid sturgeon in the lower Mississippi River

    USGS Publications Warehouse

    Herrala, Jason R.; Kroboth, Patrick T.; Kuntz, Nathan M.; Schramm, Harold L.

    2014-01-01

    The Pallid Sturgeon Scaphirhynchus albus is an endangered riverine sturgeon with historical distribution restricted to the Yellowstone, Missouri, Mississippi, and Atchafalaya rivers. Although not abundant, Pallid Sturgeon in the lower Mississippi River appear to be naturally recruiting, and information about habitat use is important to conserve this species. Thirty-four adult Pallid Sturgeon (612-1,013-mm FL) were tagged with acoustic transmitters and relocated a total of 272times in a 40-km reach of the lower Mississippi River from April 2009 through December 2012. Pallid Sturgeon strongly selected island tip and natural bank habitats, and, to a lesser degree, revetted bank habitat. Although frequently used, Pallid Sturgeon exhibited negative selection for the expansive main channel habitat. Secondary channel habitat was seasonally available and excluded from habitat selection analysis, but this habitat was frequently used in the spring when available. Fifty percent of Pallid Sturgeon detections were in relatively narrow ranges of depths (6.2-13.6m) and surface current velocities (0.64-1.05m/s). Use of different habitats was related to river stage and water temperature, suggesting use of some habitats was seasonal. Results suggest that maintaining natural bank habitat and secondary channel-island complexes will benefit conservation of this endangered species in the lower Mississippi River. 

  12. Age-0 Shovelnose Sturgeon prey consumption in the Lower Missouri River

    USGS Publications Warehouse

    Gosch, N.J.C.; Miller, M.L.; Gemeinhardt, T.R; Starks, T. A.; Civiello, A.P.; Long, James M.; Bonneau, J.L.

    2016-01-01

    A lack of nutritious food during the first year of life is a hypothesized factor that may limit survival of endangered pallid sturgeonScaphirhynchus albus in the lower Missouri River (LMOR). Unfortunately, information for age-0 pallid sturgeon diets remains limited, but diet analyses for age-0 Scaphirhynchus spp. (sturgeon hereafter) have occurred. Little information, however, exists on age-0 sturgeon diets in the LMOR; thus, our primary objective was to document age-0 sturgeon diets in this system. We examined guts contents from 30 individuals, which were genetically identified as shovelnose sturgeon Scaphirhynchus platorynchus, and three stomachs were empty. The remaining age-0 shovelnose sturgeon consumed chironomid larvae almost exclusively (>98% of prey items consumed). Our results were similar to studies conducted in other systems, and it appears unlikely that a lack of nutritious food was a major factor affecting the individuals captured during this study. This effort provides important information to help guide ongoing adaptive management efforts in the LMOR.

  13. A novel approach to surveying sturgeon using side-scan sonar and occupancy modeling

    USGS Publications Warehouse

    Flowers, H. Jared; Hightower, Joseph E.

    2013-01-01

    Technological advances represent opportunities to enhance and supplement traditional fisheries sampling approaches. One example with growing importance for fisheries research is hydroacoustic technologies such as side-scan sonar. Advantages of side-scan sonar over traditional techniques include the ability to sample large areas efficiently and the potential to survey fish without physical handling-important for species of conservation concern, such as endangered sturgeons. Our objectives were to design an efficient survey methodology for sampling Atlantic Sturgeon Acipenser oxyrinchus by using side-scan sonar and to developmethods for analyzing these data. In North Carolina and South Carolina, we surveyed six rivers thought to contain varying abundances of sturgeon by using a combination of side-scan sonar, telemetry, and video cameras (i.e., to sample jumping sturgeon). Lower reaches of each river near the saltwater-freshwater interface were surveyed on three occasions (generally successive days), and we used occupancy modeling to analyze these data.We were able to detect sturgeon in five of six rivers by using these methods. Side-scan sonar was effective in detecting sturgeon, with estimated gear-specific detection probabilities ranging from 0.2 to 0.5 and river-specific occupancy estimates (per 2-km river segment) ranging from 0.0 to 0.8. Future extensions of this occupancy modeling framework will involve the use of side-scan sonar data to assess sturgeon habitat and abundance in different river systems.

  14. Lysozyme fractionation from egg white at pilot scale by means of tangential flow membrane adsorbers: Investigation of the flow conditions.

    PubMed

    Brand, Janina; Voigt, Katharina; Zochowski, Bianca; Kulozik, Ulrich

    2016-03-18

    The application of membrane adsorbers instead of classical packed bed columns for protein fractionation is still a growing field. In the case of egg white protein fractionation, the application of classical chromatography is additionally limited due to its high viscosity that impairs filtration. By using tangential flow membrane adsorbers as stationary phase this limiting factor can be left out, as they can be loaded with particle containing substrates. The flow conditions existing in tangential flow membrane adsorbers are not fully understood yet. Thus, the aim of the present study was to gain a deeper understanding of the transport mechanisms in tangential flow membrane adsorbers. It was found that loading in recirculation mode instead of single pass mode increased the binding capacity (0.39 vs. 0.52 mg cm(-2)). Further, it was shown that either higher flow rates (0.39 mg cm(-2) vs. 0.57 mg cm(-2) at 1 CV min(-1) or 20 CV min(-1), respectively) or higher amounts of the target protein in the feed (0.24 mg cm(-2) vs. 0.85 mg cm(-2) for 2.5 or 39.0 g lysozyme, respectively) led to more protein binding. These results show that, in contrast to radial flow or flat sheet membrane adsorbers, the transport in tangential flow membrane adsorbers is not purely based on convection, but on a mix of convection and diffusion. Additionally, investigations concerning the influence of fouling formation were performed that can lead to transport limitations. It was found that this impact is neglectable. It can be concluded that the usage of tangential flow membrane adsorbers is very recommendable for egg white protein fractionations, although the transport is partly diffusion-limited. PMID:26898148

  15. Associations between white matter microstructure and amyloid burden in preclinical Alzheimer's disease: A multimodal imaging investigation

    PubMed Central

    Racine, Annie M.; Adluru, Nagesh; Alexander, Andrew L.; Christian, Bradley T.; Okonkwo, Ozioma C.; Oh, Jennifer; Cleary, Caitlin A.; Birdsill, Alex; Hillmer, Ansel T.; Murali, Dhanabalan; Barnhart, Todd E.; Gallagher, Catherine L.; Carlsson, Cynthia M.; Rowley, Howard A.; Dowling, N. Maritza; Asthana, Sanjay; Sager, Mark A.; Bendlin, Barbara B.; Johnson, Sterling C.

    2014-01-01

    Some cognitively healthy individuals develop brain amyloid accumulation, suggestive of incipient Alzheimer's disease (AD), but the effect of amyloid on other potentially informative imaging modalities, such as Diffusion Tensor Imaging (DTI), in characterizing brain changes in preclinical AD requires further exploration. In this study, a sample (N = 139, mean age 60.6, range 46 to 71) from the Wisconsin Registry for Alzheimer's Prevention (WRAP), a cohort enriched for AD risk factors, was recruited for a multimodal imaging investigation that included DTI and [C-11]Pittsburgh Compound B (PiB) positron emission tomography (PET). Participants were grouped as amyloid positive (Aβ+), amyloid indeterminate (Aβi), or amyloid negative (Aβ−) based on the amount and pattern of amyloid deposition. Regional voxel-wise analyses of four DTI metrics, fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (Da), and radial diffusivity (Dr), were performed based on amyloid grouping. Three regions of interest (ROIs), the cingulum adjacent to the corpus callosum, hippocampal cingulum, and lateral fornix, were selected based on their involvement in the early stages of AD. Voxel-wise analysis revealed higher FA among Aβ+ compared to Aβ− in all three ROIs and in Aβi compared to Aβ− in the cingulum adjacent to the corpus callosum. Follow-up exploratory whole-brain analyses were consistent with the ROI findings, revealing multiple regions where higher FA was associated with greater amyloid. Lower fronto-lateral gray matter MD was associated with higher amyloid burden. Further investigation showed a negative correlation between MD and PiB signal, suggesting that Aβ accumulation impairs diffusion. Interestingly, these findings in a largely presymptomatic sample are in contradistinction to relationships reported in the literature in symptomatic disease stages of Mild Cognitive Impairment and AD, which usually show higher MD and lower FA. Together with analyses

  16. Shovelnose sturgeon spawning in relation to varying discharge treatments in a Missouri River tributary

    USGS Publications Warehouse

    Goodman, B.J.; Guy, C.S.; Camp, S.L.; Gardner, W.M.; Kappenman, K.M.; Webb, M.A.H.

    2013-01-01

    Many lotic fish species use natural patterns of variation in discharge and temperature as spawning cues, and these natural patterns are often altered by river regulation. The effects of spring discharge and water temperature variation on the spawning of shovelnose sturgeon Scaphirhynchus platorynchus have not been well documented. From 2006 through 2009, we had the opportunity to study the effects of experimental discharge levels on shovelnose sturgeon spawning in the lower Marias River, a regulated tributary to the Missouri River in Montana. In 2006, shovelnose sturgeon spawned in the Marias River in conjunction with the ascending, peak (134 m3/s) and descending portions of the spring hydrograph and water temperatures from 16°C to 19°C. In 2008, shovelnose sturgeon spawned in conjunction with the peak (118 m3/s) and descending portions of the spring hydrograph and during a prolonged period of increased discharge (28–39 m3/s), coupled with water temperatures from 11°C to 23°C in the lower Marias River. No evidence of shovelnose sturgeon spawning was documented in the lower Marias River in 2007 or 2009 when discharge remained low (14 and 20 m3/s) despite water temperatures suitable and optimal (12°C-24°C) for shovelnose sturgeon embryo development. A similar relationship between shovelnose sturgeon spawning and discharge was observed in the Teton River. These data suggest that discharge must reach a threshold level (28 m3/s) and should be coupled with water temperatures suitable (12°C-24°C) or optimal (16°C-20°C) for shovelnose sturgeon embryo development to provide a spawning cue for shovelnose sturgeon in the lower Marias River.

  17. Sturgeon nucleo-cytoplasmic large DNA virus phylogeny and PCR tests.

    PubMed

    Clouthier, Sharon C; VanWalleghem, Elissa; Anderson, Eric D

    2015-12-01

    Sturgeon epitheliotropic nucleo-cytoplasmic large DNA viruses (NCLDVs) can cause a lethal disease of the integumentary system. These viruses have not been assigned to any currently recognized family or genus. In this study, phylogenetic analyses using the major capsid protein (MCP) showed that the sturgeon NCLDVs formed a cohesive taxonomic group, could be identified to the species or possibly sub-species level and formed a distinct evolutionary lineage within the Megavirales. The genetic relatedness of the sturgeon virus MCP allowed design of 3 PCR diagnostic tests with analytical specificity (ASp) inclusive of this group of viruses. The conventional PCR test, C1, had broader ASp than the 2 quantitative PCR tests, Q1 and Q2, and was inclusive of the sturgeon viruses as well as some viruses belonging to the families Mimi-, Phycodna-, or Iridoviridae. Q2 had broader specificity than Q1 but both tests recognized the sturgeon NCLDVs and did not cross-react with co-localizing sturgeon herpesviruses. Analytical test performance characteristics evaluated for Q1 and Q2 revealed sensitive assays with observed 50% limits of detection between 3 and 6.25 plasmid copies and high intra- and inter-assay repeatability. Q1 was used to test for sturgeon viruses in endangered populations of lake sturgeon Acipenser fulvescens within the Winnipeg River or Nelson River drainage systems of Manitoba, Canada. Test results indicated that namao virus is endemic in the Nelson River water basin. These tests meet the analytical requirements for diagnostic testing in Canada and are useful tools for disease management in sturgeon conservation stocking programs in North America. PMID:26648102

  18. Sturgeon nucleo-cytoplasmic large DNA virus phylogeny and PCR tests.

    PubMed

    Clouthier, Sharon C; VanWalleghem, Elissa; Anderson, Eric D

    2015-12-01

    Sturgeon epitheliotropic nucleo-cytoplasmic large DNA viruses (NCLDVs) can cause a lethal disease of the integumentary system. These viruses have not been assigned to any currently recognized family or genus. In this study, phylogenetic analyses using the major capsid protein (MCP) showed that the sturgeon NCLDVs formed a cohesive taxonomic group, could be identified to the species or possibly sub-species level and formed a distinct evolutionary lineage within the Megavirales. The genetic relatedness of the sturgeon virus MCP allowed design of 3 PCR diagnostic tests with analytical specificity (ASp) inclusive of this group of viruses. The conventional PCR test, C1, had broader ASp than the 2 quantitative PCR tests, Q1 and Q2, and was inclusive of the sturgeon viruses as well as some viruses belonging to the families Mimi-, Phycodna-, or Iridoviridae. Q2 had broader specificity than Q1 but both tests recognized the sturgeon NCLDVs and did not cross-react with co-localizing sturgeon herpesviruses. Analytical test performance characteristics evaluated for Q1 and Q2 revealed sensitive assays with observed 50% limits of detection between 3 and 6.25 plasmid copies and high intra- and inter-assay repeatability. Q1 was used to test for sturgeon viruses in endangered populations of lake sturgeon Acipenser fulvescens within the Winnipeg River or Nelson River drainage systems of Manitoba, Canada. Test results indicated that namao virus is endemic in the Nelson River water basin. These tests meet the analytical requirements for diagnostic testing in Canada and are useful tools for disease management in sturgeon conservation stocking programs in North America.

  19. Survival of hatchery Gulf sturgeon (Acipenser oxyrinchus desotoi Mitchill, 1815) in the Suwannee River, Florida: a 19-year evaluation

    USGS Publications Warehouse

    Sulak, Kenneth J.; Randall, Michael; Clugston, J.P.

    2014-01-01

    An experimental release of 1192 hatchery-reared, individually PIT tagged, 220 days old (296–337 mm TL) Gulf sturgeon, Acipenser oxyrinchus desotoi, was undertaken in 1992 in the Suwannee River, Florida. The original objectives of the 1992 release experiment were to: (1) evaluate survival rate of cultured Gulf sturgeon in the wild vs survival rate of their wild 1992 cohort counterparts, (2) determine the differential effect of release site within the river upon long-term survival, and (3) evaluate comparative growth rates of recaptured hatchery vs captured wild 1992 cohort Gulf sturgeon. The present investigation addressed those original objectives, plus an additional fourth objective: (4) evaluation of hatchery fish recapture rate change over the 19-year experiment. The primary objective was to determine efficacy of potential conservation aquaculture for this species in terms of long-term survival in the wild. Follow-up 1993–2011 gill net sampling in freshwater reaches (rkm 4–237) and the estuarine river mouth (rkm −6 to 4) yielded recaptures representing 13.0% of the total released. Mean annual hatchery fish mortality (including emigration) rate estimated for the 19-year period (1993–2011) was more than twice that for same cohort wild fish. Mark-recapture survival probability (phi) for hatchery fish, 1993–2011, was substantially lower (0.733) than for their wild counterparts (0.888). Mean annual hatchery fish recapture rate, as a percentage of all 1992 cohort fish recaptures, declined significantly after age-7, coinciding with age of onset of migration into the open Gulf of Mexico. Hypothesized causal factors may be differentially lower fitness in the marine habitat or permanent outmigration due to natal river imprinting failure. Hatchery fish recapture rates varied significantly for fish from the ten release sites, being highest near the river mouth, and lowest for the furthest upriver sites in the Suwannee River and its Santa Fe River tributary

  20. Age and growth of lake sturgeon in the upper St. Lawrence River

    USGS Publications Warehouse

    Johnson, J.H.; Dropkin, D.S.; LaPan, S.R.; McKenna, J.E.; Klindt, R.M.

    1998-01-01

    The growth of lake sturgeon (Acipenser fulvescens) over time in the upper St. Lawrence River was examined. Growth of lake sturgeon collected during 1993 and 1994 below Robert Moses Dam near Massena, New York, was compared to that reported for the same population almost 25 years earlier. The data suggest that lake sturgeon growth was similar to that reported in the previous study. However, significant differences in the elevations of regression models between males and fish of unknown sex in both data sets suggest possible sexual dimorphism in growth at younger ages.

  1. Effects of Seismic Air Guns on Pallid Sturgeon and Paddlefish.

    PubMed

    Popper, Arthur N; Carlson, Thomas J; Gross, Jackson A; Hawkins, Anthony D; Zeddies, David; Powell, Lynwood; Young, John

    2016-01-01

    Pallid sturgeon and paddlefish were placed at different distances from a seismic air gun array to determine the potential effects on mortality and nonauditory body tissues from the sound from a single shot. Fish were held 7 days postexposure and then necropsied. No fish died immediately after sound exposure or over the postexposure period. Statistical analysis of injuries showed no differences between the experimental and control animals in either type or severity of injuries. There was also no difference in injuries between fish exposed closest to the source compared with those exposed furthest from the source. PMID:26611044

  2. Effects of Seismic Air Guns on Pallid Sturgeon and Paddlefish.

    PubMed

    Popper, Arthur N; Carlson, Thomas J; Gross, Jackson A; Hawkins, Anthony D; Zeddies, David; Powell, Lynwood; Young, John

    2016-01-01

    Pallid sturgeon and paddlefish were placed at different distances from a seismic air gun array to determine the potential effects on mortality and nonauditory body tissues from the sound from a single shot. Fish were held 7 days postexposure and then necropsied. No fish died immediately after sound exposure or over the postexposure period. Statistical analysis of injuries showed no differences between the experimental and control animals in either type or severity of injuries. There was also no difference in injuries between fish exposed closest to the source compared with those exposed furthest from the source.

  3. Upstream migration of two pre-spawning shortnose sturgeon passed upstream of Pinopolis Dam, Cooper River, South Carolina

    USGS Publications Warehouse

    Finney, S.T.; Isely, J.J.; Cooke, D.W.

    2006-01-01

    Two shortnose sturgeon were artificially passed above the Pinopolis Lock and Dam into the Santee-Cooper Lakes in order to simulate the use of a fish-passage mechanism. Movement patterns and spawning behavior were studied to determine the potential success of future shortnose sturgeon migrations if and when a fish-migration bypass structure is installed. In addition to movement patterns, water temperature was monitored in areas that shortnose sturgeons utilized. Shortnose sturgeon migrated through a large static system to a known shortnose sturgeon spawning area more than 160 km upstream where water temperatures were consistent with known shortnose sturgeon spawning temperatures. No specific movement patterns in the reservoir system were recorded during downstream migrations.

  4. Investigating and managing the rapid emergence of white-nose syndrome, a novel, fatal, infectious disease of hibernating bats

    USGS Publications Warehouse

    Foley, Janet; Clifford, Deana; Castle, Kevin; Cryan, Paul M.; Ostfeld, Richard S.

    2011-01-01

    White-nose syndrome (WNS) is a fatal disease of bats that hibernate. The etiologic agent of WNS is the fungus Geomyces destructans, which infects the skin and wing membranes. Over 1 million bats in six species in eastern North America have died from WNS since 2006, and as a result several species of bats may become endangered or extinct. Information is lacking on the pathogenesis of G. destructans and WNS, WNS transmission and maintenance, individual and site factors that contribute to the probability of an outbreak of WNS, and spatial dynamics of WNS spread in North America. We considered how descriptive and analytical epidemiology could be used to fill these information gaps, including a four-step (modified) outbreak investigation, application of a set of criteria (Hill's) for assessing causation, compartment models of disease dynamics, and spatial modeling. We cataloged and critiqued adaptive-management options that have been either previously proposed for WNS or were helpful in addressing other emerging diseases of wild animals. These include an ongoing program of prospective surveillance of bats and hibernacula for WNS, treatment of individual bats, increasing population resistance to WNS (through vaccines, immunomodulators, or other methods), improving probability of survival from starvation and dehydration associated with WNS, modifying hibernacula environments to eliminate G. destructans, culling individuals or populations, controlling anthropogenic spread of WNS, conserving genetic diversity of bats, and educating the public about bats and bat conservation issues associated with WNS.

  5. Food habits of Atlantic sturgeon off the central New Jersey coast

    USGS Publications Warehouse

    Johnson, J.H.; Dropkin, D.S.; Warkentine, B.E.; Rachlin, J.W.; Andrews, W.D.

    1997-01-01

    Limited information exists on the marine diet of the Atlantic sturgeon Acipenser oxyrinchus oxyrinchus. We examined the food habits of 275 Atlantic sturgeon (total length, 106-203 cm) caught in the commercial fishery off the coast of New Jersey. Stomachs were provided by fishermen. Significantly more stomachs were empty in the spring than in the fall. Sand and organic debris were a major component in the stomachs (26.3-75.4% by weight). Polycheates were the primary pre group consumed, although the isopod Politolana conchorum was the most important individual prey eaten. Mollusks and fish contributed little to the diet. Some prey taxa (i.e., polychaetes, isopods, amphipods) exhibited seasonal variation in importance in the diet of Atlantic sturgeon. Identification of the offshore diet of Atlantic sturgeon is an important step in developing a better understanding of the life history requirements and marine ecology of this species.

  6. Management and recovery options for Ural river beluga sturgeon.

    PubMed

    Doukakis, Phaedra; Babcock, Elizabeth A; Pikitch, Ellen K; Sharov, Alexei R; Baimukhanov, Mirgaly; Erbulekov, Sagiden; Bokova, Yelena; Nimatov, Akhat

    2010-06-01

    Management of declining fisheries of anadromous species sometimes relies heavily on supplementation of populations with captive breeding, despite evidence that captive breeding can have negative consequences and may not address the root cause of decline. The beluga sturgeon (Huso huso), a species threatened by the market for black caviar and reductions in habitat quality, is managed through harvest control and hatchery supplementation, with an emphasis on the latter. We used yield per recruit and elasticity analyses to evaluate the population status and current levels of fishing and to identify the life-history stages that are the best targets for conservation of beluga of the Ural River. Harvest rates in recent years were four to five times higher than rates that would sustain population abundance. Sustainable rates of fishing mortality are similar to those for other long-lived marine species such as sharks and mammals. Yield per recruit, which is maximized if fish are first harvested at age 31 years, would be greatly enhanced by raising minimum size limits or reducing illegal take of subadults. Improving the survival of subadult and adult females would increase population productivity by 10 times that achieved by improving fecundity and survival from egg to age 1 year (i.e., hatchery supplementation). These results suggest that reducing mortality of subadults and adult wild fish is a more effective conservation strategy than hatchery supplementation. Because genetics is not factored into hatchery management practices, supplementation may even reduce the viability of the beluga sturgeon.

  7. Sedimentology and sequence stratigraphy of the Sturgeon Lake field, Alberta

    SciTech Connect

    Mederos, S.M.; Moslow, T.F.

    1996-08-01

    This study examines the sedimentology, sequence stratigraphy and reservoir characterization of the Lower Triassic Montney Formation in the Sturgeon Lake field located in west-central Alberta. The Montney Formation is grouped into two facies associations. Facies Association 1 is a siliciclastic upward-coarsening sequence deposited by storm, current and wave processes and is interpreted as a low energy progradational lower shoreface. Facies Association 2 is a carbonate shallowing upward sequence deposited in a wave dominated progradational shoreface. The contact between Facies Association 1 and 2 is marked by a major change in lithology and is erosive. Palynological analyses reveal two missing palynologic subzones between Facies Association 1 and Facies Association 2 suggesting a period of erosion and/or nondeposition. The boundary between the two facies association is defined as a sequence boundary which stratigraphically divides the Montney Formation into two sequences in the study area. The Lower Montney sequence is composed of eight retrogradational, aggradational and progradational parasequences and represent the Transgressive and the High-stand System Tract. The Upper Montney sequence is composed only of one parasequence and represents the Transgressive System Tract. The Sturgeon Lake Field has two types of reservoir with respect to lithology, porosity, permeability and geometry. The best reservoir facies is a brachiopod wackestone-packstone with permeabilities up to 8 Darcys. Siliciclastic reservoirs consist of very fine grained sandstones with permeabilities of 132 md when fractured.

  8. Lake sturgeon population attributes and reproductive structure in the Namakan Reservoir, Minnesota and Ontario

    USGS Publications Warehouse

    Shaw, S. L.; Chipps, Steven R.; Windels, S. K.; Webb, M.A.H.; McLeod, D. T.; Willis, D.W.

    2012-01-01

    Quantified were the age, growth, mortality and reproductive structure of lake sturgeon (Acipenser fulvescens) collected in the US and Canadian waters of the Namakan Reservoir. The hypotheses were tested that (i) age and growth of lake sturgeon in the Namakan Reservoir would differ by sex and reproductive stage of maturity, and (ii) that the relative strength of year-classes of lake sturgeon in the reservoir would be affected by environmental variables. To quantify age, growth and mortality of the population, existing data was used from a multi-agency database containing information on all lake sturgeon sampled in the reservoir from 2004 to 2009. Lake sturgeon were sampled in the Minnesota and Ontario waters of the Namakan Reservoir using multi-filament gillnets 1.8 m high and 30–100 m long and varying in mesh size from 178 to 356 mm stretch. Reproductive structure of the lake sturgeon was assessed only during spring 2008 and 2009 using plasma testosterone and estradiol-17β concentrations. Ages of lake sturgeon >75 cm ranged from 9 to 86 years (n = 533, mean = 36 years). A catch-curve analysis using the 1981–1953 year classes estimated total annual mortality of adults to be 4.8% and annual survival as 95.2%. Using logistic regression analysis, it was found that total annual precipitation was positively associated with lake sturgeon year-class strength in the Namakan Reservoir. A 10 cm increase in total annual precipitation was associated with at least a 39% increase in the odds of occurrence of a strong year class of lake sturgeon in the reservoir. Plasma steroid analysis revealed a sex ratio of 2.4 females: 1 male and, on average, 10% of female and 30% of male lake sturgeon were reproductively mature each year (i.e. potential spawners). Moreover, there was evidence based on re-captured male fish of both periodic and annual spawning, as well as the ability of males to rapidly undergo gonadal maturation prior to spawning. Knowledge of lake sturgeon

  9. Fins improve the swimming performance of fish sperm: a hydrodynamic analysis of the Siberian sturgeon Acipenser baerii.

    PubMed

    Gillies, Eric A; Bondarenko, Volodymyr; Cosson, Jacky; Pacey, Allan A

    2013-02-01

    The flagella of sturgeon sperm have an ultrastructure comprising paddle-like fins extending along most of their length. These fins are seen in several other marine and freshwater fish. The sperm of these fish are fast swimmers and are relatively short lived: it is therefore tempting to think of these fins as having evolved for hydrodynamic advantage, but the actual advantage they impart, at such a small length scale and slow speed, is unclear. The phrase "the fins improve hydrodynamic efficiency" is commonly found in biological literature, yet little hydrodynamic analysis has previously been used to support such conjectures. In this paper, we examine various hydrodynamic models of sturgeon sperm and investigate both swimming velocity and energy expenditure. All of the models indicate a modest hydrodynamic advantage of finned sperm, in both straight line swimming speed and a hydrodynamic efficiency measure. We find a hydrodynamic advantage for a flagellum with fins, over one without fins, of the order of 15-20% in straight line propulsive velocity and 10-15% in a hydrodynamic efficiency measure. PMID:23233331

  10. Frequency tuning and intensity coding of sound in the auditory periphery of the lake sturgeon, Acipenser fulvescens

    PubMed Central

    Meyer, Michaela; Fay, Richard R.; Popper, Arthur N.

    2010-01-01

    Acipenser fulvescens, the lake sturgeon, belongs to one of the few extant non-teleost ray-finned (bony) fishes. The sturgeons (family Acipenseridae) have a phylogenetic history that dates back about 250 million years. The study reported here is the first investigation of peripheral coding strategies for spectral analysis in the auditory system in a non-teleost bony fish. We used a shaker system to simulate the particle motion component of sound during electrophysiological recordings of isolated single units from the eighth nerve innervating the saccule and lagena. Background activity and response characteristics of saccular and lagenar afferents (such as thresholds, response–level functions and temporal firing) resembled the ones found in teleosts. The distribution of best frequencies also resembled data in teleosts (except for Carassius auratus, goldfish) tested with the same stimulation method. The saccule and lagena in A. fulvescens contain otoconia, in contrast to the solid otoliths found in teleosts, however, this difference in otolith structure did not appear to affect threshold, frequency tuning, intensity- or temporal responses of auditory afferents. In general, the physiological characteristics common to A. fulvescens, teleosts and land vertebrates reflect important functions of the auditory system that may have been conserved throughout the evolution of vertebrates. PMID:20400642

  11. Dietary Administration of Lactobacillus plantarum Enhanced Growth Performance and Innate Immune Response of Siberian Sturgeon, Acipenser baerii.

    PubMed

    Pourgholam, Moheb Ali; Khara, Hossein; Safari, Reza; Sadati, Mohammad Ali Yazdani; Aramli, Mohammad Sadegh

    2016-03-01

    We investigated the effects of Lactobacillus plantarum used as a dietary supplement on the growth performance and innate immune response in juvenile Siberian sturgeon Acipenser baerii. Juvenile fish (14.6 ± 2.3 g) were fed three experimental diets prepared by supplementing a basal diet with L. plantarum at different concentrations [1 × 10(7), 1 × 10(8) and 1 × 10(9) colony-forming units (cfu) g(-1)] and a control (non-supplemented basal) diet for 8 weeks. Growth performance indices were increased in fish fed the 1 × 10(8) cfu g(-1) L. plantarum diet compared to the other groups. There was an increased innate immune response in fish fed the experimental diets. The highest levels of lysozyme activity, total immunoglobulin (IgM) and complement component 3 (C3) were observed in fish fed the diet containing L. plantarum at a concentration of 1 × 10(8) cfu g(-1), but there was no significant difference in the level of complement component 4 (C4) in fish fed the experimental diets or the control diet. The present study underlying some positive effects (growth performance and immune indices) of dietary administration of L. plantarum at a concentration of 1 × 10(8) cfu g(-1) in the Siberian sturgeon.

  12. Diet composition of larval and young-of-year shovelnose sturgeon in the Upper Missouri River

    USGS Publications Warehouse

    Braaten, P. J.; Fuller, D.B.; McClenning, N.D.

    2007-01-01

    Obtaining food following the transition from endogenous to exogenous feeding and during the first year of life is a critical event that strongly influences growth and survival of young-of-year fishes. For shovelnose sturgeon Scaphirhynchus platorynchus, limited information is available on food habits during the first year of life. The objective of this study was to quantify diet components of shovelnose sturgeon during the transition from endogenous to exogenous feeding and during the young-of-year life stage in the North Dakota and Montana portions of the Missouri River. Young-of-year shovelnose sturgeon were sampled between early August and early September 2003. Shovelnose sturgeon initiated exogenous feeding by 16 mm, and individuals 16–140 mm fed exclusively on two macroinvertebrate orders (Diptera and Ephemeroptera). Young-of-year shovelnose sturgeon exhibited an apparently high feeding success as 99 of 100 individuals contained food in the gut. The number of organisms in the gut increased exponentially with fish length for larval Diptera (r2 = 0.73, P < 0.0001) and linearly (r2 = 0.12, P = 0.0006) for larval Ephemeroptera, but the number of Diptera pupae in the gut was not significantly related (P = 0.55) to length of young-of-year shovelnose sturgeon. The length of ingested prey was linearly related to fish length for Diptera larvae (r2 = 0.20, P = 0.002), whereas the relationship between lengths of ingested Ephemeroptera larvae and lengths of young-of-year shovelnose sturgeon was best described by a power function (r2 = 0.50, P < 0.0001). These results provide the first quantification of feeding dynamics for young-of-year shovelnose sturgeon in a natural river environment.

  13. Diet composition of larval and young-of-year shovelnose sturgeon in the Upper Missouri River

    USGS Publications Warehouse

    Braaten, P.J.; Fuller, D.B.; McClenning, N.D.

    2007-01-01

    Obtaining food following the transition from endogenous to exogenous feeding and during the first year of life is a critical event that strongly influences growth and survival of young-of-year fishes. For shovelnose sturgeon Scaphirhynchus platorynchus, limited information is available on food habits during the first year of life. The objective of this study was to quantify diet components of shovelnose sturgeon during the transition from endogenous to exogenous feeding and during the young-of-year life stage in the North Dakota and Montana portions of the Missouri River. Young-of-year shovelnose sturgeon were sampled between early August and early September 2003. Shovelnose sturgeon initiated exogenous feeding by 16 mm, and individuals 16-140 mm fed exclusively on two macroinvertebrate orders (Diptera and Ephemeroptera). Young-of-year shovelnose sturgeon exhibited an apparently high feeding success as 99 of 100 individuals contained food in the gut. The number of organisms in the gut increased exponentially with fish length for larval Diptera (r2 = 0.73, P < 0.0001) and linearly (r2 = 0.12, P = 0.0006) for larval Ephemeroptera, but the number of Diptera pupae in the gut was not significantly related (P = 0.55) to length of young-of-year shovelnose sturgeon. The length of ingested prey was linearly related to fish length for Diptera larvae (r2 = 0.20, P = 0.002), whereas the relationship between lengths of ingested Ephemeroptera larvae and lengths of young-of-year shovelnose sturgeon was best described by a power function (r2 = 0.50, P < 0.0001). These results provide the first quantification of feeding dynamics for young-of-year shovelnose sturgeon in a natural river environment. ?? 2007 Blackwell Verlag.

  14. Documentation of a Gulf sturgeon spawning site on the Yellow River, Alabama, USA

    USGS Publications Warehouse

    Kreiser, Brian R.; Berg, J.; Randall, M.; Parauka, F.; Floyd, S.; Young, B.; Sulak, Kenneth J.

    2008-01-01

    Parauka and Giorgianni (2002) reported that potential Gulf sturgeon spawning habitat is present in the Yellow River; however, efforts to document spawning by the collection of eggs or larvae have been unsuccessful in the past. Herein, we report on the first successful collection of eggs from a potential spawning site on the Yellow River and the verification of their identity as Gulf sturgeon by using molecular methods.

  15. Green Sturgeon Distribution in the Pacific Ocean Estimated from Modeled Oceanographic Features and Migration Behavior

    PubMed Central

    Huff, David D.; Lindley, Steven T.; Wells, Brian K.; Chai, Fei

    2012-01-01

    The green sturgeon (Acipenser medirostris), which is found in the eastern Pacific Ocean from Baja California to the Bering Sea, tends to be highly migratory, moving long distances among estuaries, spawning rivers, and distant coastal regions. Factors that determine the oceanic distribution of green sturgeon are unclear, but broad-scale physical conditions interacting with migration behavior may play an important role. We estimated the distribution of green sturgeon by modeling species-environment relationships using oceanographic and migration behavior covariates with maximum entropy modeling (MaxEnt) of species geographic distributions. The primary concentration of green sturgeon was estimated from approximately 41–51.5° N latitude in the coastal waters of Washington, Oregon, and Vancouver Island and in the vicinity of San Francisco and Monterey Bays from 36–37° N latitude. Unsuitably cold water temperatures in the far north and energetic efficiencies associated with prevailing water currents may provide the best explanation for the range-wide marine distribution of green sturgeon. Independent trawl records, fisheries observer records, and tagging studies corroborated our findings. However, our model also delineated patchily distributed habitat south of Monterey Bay, though there are few records of green sturgeon from this region. Green sturgeon are likely influenced by countervailing pressures governing their dispersal. They are behaviorally directed to revisit natal freshwater spawning rivers and persistent overwintering grounds in coastal marine habitats, yet they are likely physiologically bounded by abiotic and biotic environmental features. Impacts of human activities on green sturgeon or their habitat in coastal waters, such as bottom-disturbing trawl fisheries, may be minimized through marine spatial planning that makes use of high-quality species distribution information. PMID:23029274

  16. Contamination by organochlorine compounds in the edible tissue of four sturgeon species from the Caspian Sea (Iran).

    PubMed

    Hosseini, Seyed Vali; Behrooz, Reza Dahmardeh; Esmaili-Sari, Abbas; Bahramifar, Nader; Hosseini, Seyed Mehdi; Tahergorabi, Reza; Hosseini, Seyed Fakhreddin; Feás, Xesús

    2008-10-01

    This study focused on accumulation of organochlorine compounds (OCs), including dichloro-diphenyl-trichloroethanes (DDTs), hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), and polychlorinated biphenyls (PCBs) accumulation in the muscle of four sturgeon (Persian sturgeon, Acipenser persicus; Stellate sturgeon, Acipenser stellatus; Ship sturgeon, Acipenser nudiventris and Beluga sturgeon, Huso huso) from the southern Caspian Sea. The DDT group was prominent in all of the sturgeon muscle tested constituting almost half or more of the total organochlorine content. Contaminant concentration generally followed this order: DDTs>PCBs>HCHs>HCB. The OCs concentrations in Beluga sturgeon (H. huso) were the highest and over four times higher than in the next highest species (A. nudiventris). From an ecotoxicological point of view, the concentrations of OCs in experimental fishes do not reflect a comparatively clean and pollution-free environment; however, results from this study shown that the inflow of organic pollutants into the Caspian Sea has been reduced when compared with prior studies. Levels of measured OCs in sturgeon were relatively low, but the level of some OCs in some of the specimens tested exceeded the guidelines for food; therefore, the maximum allowable daily consumption rate for sturgeon from this watershed may be limited by DDTs and PCBs content for high risk populations.

  17. Seasonal movement and mesohabitat usage of adult and juvenile lake sturgeon in the Grasse River, New York

    USGS Publications Warehouse

    Trested, D.G.; Chan, Matthew D.; Bridges, W.C.; Isely, J.J.

    2011-01-01

    Long-term restoration efforts for lake sturgeon Acipenser fulvescens populations will benefit from better understanding of this species' movements and habitat use in riverine systems. Radio transmitters were implanted in both juvenile and adult lake sturgeon in the Grasse River, New York, and individuals were relocated over a 2-year period. Adult lake sturgeon demonstrated greater minimum daily distance moved, absolute distance moved, and mean home range size than juvenile lake sturgeon during the spring. During the course of the study, both adult and juvenile lake sturgeon exhibited movements upstream and downstream through a breached low-head weir, and individuals did not necessarily remain resident on an annual basis in the Grasse River. Mesohabitat and substrate use patterns were determined based on comparisons of frequency distributions for relocated lake sturgeon and quantified mesohabitat and substrate over a 15-km river reach. Lake sturgeon used pool mesohabitat and limited their use of run mesohabitat under both low- and mid-flow conditions. During most of the year, adult and juvenile lake sturgeon were detected over silt substrate. This study illustrates behavioral differences and similarities between the movements and habitat use of adult and juvenile lake sturgeon in a riverine system.

  18. Capture locations and growth rates of Atlantic sturgeon in the Chesapeake Bay

    USGS Publications Warehouse

    Welsh, S.A.; Eyler, S.M.; Mangold, M.F.; Spells, A.J.

    2002-01-01

    Little information exists on temporal and spatial distributions of wild and hatchery-reared Atlantic sturgeon Acipenser oxyrinchus oxyrinchus in the Chesapeake Bay. Approximately 3,300 hatchery-reared Atlantic sturgeon comprised of two size groups were released into the Nanticoke River, a tributary of the Chesapeake Bay, on 8 July 1996. During January 1996-May 2000, 1099 Atlantic sturgeon were captured incidentally (i.e., bycatch) by commercial watermen in the Chesapeake Bay, including 420 hatchery-reared individuals. Wild and hatchery-reared Atlantic sturgeon were captured primarily in pound nets and gill nets. Biologists tagged each fish and recorded weight, length, and location of capture. Although two adults greater than 2000 mm fork length (FL) were captured in Maryland waters, wild sturgeon were primarily juveniles from Maryland and Virginia waters (415 and 259 individuals below 1000 mm FL, respectively). A growth rate of 0.565 mm/d (N = 15, SE = 0.081) was estimated for wild individuals (487-944 mm TL at release) at liberty from 30 to 622 d. The average growth of the group of hatchery-reared Atlantic sturgeon raised at 10??C exceeded that of the group raised at 17??C. Our distributional data based on capture locations are biased by fishery dependence and gear selectivity. These data are informative to managers, however, because commercial effort is widely distributed in the Chesapeake Bay, and little distributional data were available before this study.

  19. Use of behavioral and physiological indicators to evaluate Scaphirhynchus sturgeon spawning success

    USGS Publications Warehouse

    DeLonay, A.J.; Papoulias, D.M.; Wildhaber, M.L.; Annis, M.L.; Bryan, J.L.; Griffith, S.A.; Holan, S.H.; Tillitt, D.E.

    2007-01-01

    Thirty gravid, female shovelnose sturgeon (Scaphirhynchus platorynchus) were captured in the Lower Missouri River in March 2004 to evaluate the effectiveness of physiology, telemetry and remote sensor technology coupled with change point analysis in identifying when and where Scaphirhynchus sturgeon spawn. Captured sturgeons were instrumented with ultrasonic transmitters and with archival data storage tags (DST) that recorded temperature and pressure. Female sturgeon were tracked through the suspected spawning period. Thereafter, attempts were made to recapture fish to evaluate spawning success. At the time of transmitter implantation, blood and an ovarian biopsy were taken. Reproductive hormones and cortisol were measured in blood. Polarization indices and germinal vesicle breakdown were assessed on the biopsied oocytes to determine readiness to spawn. Behavioral data collected using telemetry and DST sensors were used to determine the direction and magnitude of possible spawning-related movements and to identify the timing of potential spawning events. Upon recapture observations of the ovaries and blood chemistry provided measures of spawning success and comparative indicators to explain differences in observed behavior. Behavioral and physiological indicators of spawning interpreted along with environmental measures may assist in the determination of variables that may cue sturgeon reproduction and the conditions under which sturgeon successfully spawn. ?? 2007 Blackwell Verlag.

  20. Estimating sturgeon abundance in the Carolinas using side-scan sonar

    USGS Publications Warehouse

    Flowers, H. Jared; Hightower, Joseph E.

    2015-01-01

    Sturgeons (Acipenseridae) are one of the most threatened taxa worldwide, including species in North Carolina and South Carolina. Populations of Atlantic Sturgeon Acipenser oxyrinchus in the Carolinas have been significantly reduced from historical levels by a combination of intense fishing and habitat loss. There is a need for estimates of current abundance, to describe status, and for estimates of historical abundance in order to provide realistic recovery goals. In this study we used N-mixture and distance models with data acquired from side-scan sonar surveys to estimate abundance of sturgeon in six major sturgeon rivers in North Carolina and South Carolina. Estimated abundances of sturgeon greater than 1 m TL in the Carolina distinct population segment (DPS) were 2,031 using the count model and 1,912 via the distance model. The Pee Dee River had the highest overall abundance of any river at 1,944 (count model) or 1,823 (distance model). These estimates do not account for sturgeon less than 1 m TL or occurring in riverine reaches not surveyed or in marine waters. Comparing the two models, the N-mixture model produced similar estimates using less data than the distance model with only a slight reduction of estimated precision.

  1. Atlantic sturgeons (Acipenser sturio, Acipenser oxyrinchus): American females successful in Europe

    NASA Astrophysics Data System (ADS)

    Tiedemann, Ralph; Moll, Katja; Paulus, Kirsten B.; Scheer, Michael; Williot, Patrick; Bartel, Ryszard; Gessner, Jörn; Kirschbaum, Frank

    2007-03-01

    Recent molecular data on the maternally inherited mitochondrial (mt) DNA have challenged the traditional view that the now extinct Baltic sturgeon population belonged to the European sturgeon Acipenser sturio. Instead, there is evidence that American sea sturgeon Acipenser oxyrinchus historically immigrated into the Baltic Sea. In this study, we test the hypothesis that A. oxyrinchus introgressed into, rather than replaced, the A. sturio population in the Baltic. We established four single nucleotide polymorphisms (SNPs) in the nuclear MHC II antigen gene with a species-specific SNP pattern. Using an ancient DNA approach and two independent lines of molecular evidence (sequencing of allele-specific clones, SNaPshot), we detected both A. sturio and A. oxyrinchus alleles in the available museum material of the now extinct Baltic sturgeon population. The hybrid nature of the Baltic population was further confirmed by very high levels of heterozygosity. It had been previously postulated that the immigration of the cold-adapted A. oxyrinchus into the Baltic occurred during the Medieval Little Ice Age, when temperature likely dropped below the degree inducing spawning in A. sturio. Under this scenario, our new findings suggest that the genetic mosaic pattern in the Baltic sturgeon population (oxyrinchus mtDNA, sturio and oxyrinchus MHC alleles) is possibly caused by sex-biased introgression where spawning was largely restricted to immigrating American females, while fertilization was predominantly achieved by abundant local European males. The hybrid nature of the former Baltic sturgeon population should be taken into account in the current reintroduction measures.

  2. Age, growth, mortality, and abundance of lake sturgeon in the Grasse River, New York, USA

    USGS Publications Warehouse

    Trested, D.G.; Isely, J.J.

    2011-01-01

    An increased understanding of lake sturgeon (Acipenser fulvescens) population dynamics is a key requirement for successful management efforts. Little is known regarding the Grasse River population of lake sturgeon except that it is one of a few populations in New York State where spawning has been documented. Thus our purpose was to assess the current status of lake sturgeon in the Grasse River system, including age, growth, mortality, and abundance. Age was determined for 196 of 211 lake sturgeon by examination of sectioned pectoral fin rays. Ages ranged from 0 to 32 years and the annual mortality rate for fish between ages 7 and 14 was 16.8%. The weight (W, g) to total length (TL, mm) relationship was W = 1.281 x 10-6TL3.202. The von Bertalanffy growth equation was TL = 1913(1-e-0.0294(t+9.5691)). While the range of observed ages was similar to that of nearby St. Lawrence River populations, mean weight at age for an individual at 1000 mm TL was lower than that observed for lake sturgeon within Lake St. Francis of the St. Lawrence River. Predicted growth based on von Bertalanffy parameters was similar to that observed for the nearby Lake St. Francis. An open population estimator using the POPAN sub-module in the Program MARK produced an abundance estimate of 793 lake sturgeon (95% CI = 337-1249).

  3. Ecological requirements for pallid sturgeon reproduction and recruitment in the Lower Missouri River: Annual report 2010

    USGS Publications Warehouse

    DeLonay, Aaron J.; Jacobson, Robert B.; Papoulias, Diana M.; Wildhaber, Mark L.; Chojnacki, Kimberly A.; Pherigo, Emily K.; Haas, Justin D.; Mestl, Gerald E.

    2012-01-01

    The Comprehensive Sturgeon Research Project is a multiyear, multiagency collaborative research framework developed to provide information to support pallid sturgeon recovery and Missouri River management decisions. The project strategy integrates field and laboratory studies of sturgeon reproductive ecology, early life history, habitat requirements, and physiology. The project scope of work is developed annually with cooperating research partners and in collaboration with the U.S. Army Corps of Engineers, Missouri River Recovery—Integrated Science Program. The research consists of several interdependent and complementary tasks that engage multiple disciplines. The research tasks in the 2010 scope of work primarily address spawning as a probable factor limiting pallid sturgeon survival and recovery, although limited pilot studies also have been initiated to examine the requirements of early life stages. The research is designed to inform management decisions affecting channel re-engineering, flow modification, and pallid sturgeon population augmentation on the Missouri River, and throughout the range of the species. Research and progress made through this project are reported to the U.S. Army Corps of Engineers annually. This annual report details the research effort and progress made by the Comprehensive Sturgeon Research Project during 2010.

  4. Ecological requirements for pallid sturgeon reproduction and recruitment in the Missouri River: annual report 2011

    USGS Publications Warehouse

    DeLonay, Aaron J.; Jacobson, Robert B.; Chojnacki, Kimberly A.; Annis, Mandy L.; Braaten, P. J.; Elliott, Caroline M.; Fuller, D. B.; Haas, Justin D.; Haddix, Tyler M.; Ladd, Hallie L.A.; McElroy, Brandon J.; Mestl, Gerald E.; Papoulias, Diana M.; Rhoten, Jason C.; Wildhaber, Mark L.

    2014-01-01

    The Comprehensive Sturgeon Research Project is a multiyear, multiagency collaborative research framework developed to provide information to support pallid sturgeon recovery and Missouri River management decisions. The project strategy integrates field and laboratory studies of sturgeon reproductive ecology, early life history, habitat requirements, and physiology. The project scope of work is developed annually with cooperating research partners and in collaboration with the U.S. Army Corps of Engineers, Missouri River Recovery—Integrated Science Program. The research consists of several interdependent and complementary tasks that engage multiple disciplines. The research tasks in the 2011 scope of work emphasized understanding of reproductive migrations and spawning of adult sturgeon, and hatch and drift of larvae. These tasks were addressed in three hydrologically and geomorphologically distinct parts of the Missouri River Basin: the Lower Missouri River downstream from Gavins Point Dam, the Upper Missouri River downstream from Fort Peck Dam and including downstream reaches of the Milk River, and the Lower Yellowstone River. The research is designed to inform management decisions related to channel re-engineering, flow modification, and pallid sturgeon population augmentation on the Missouri River, and throughout the range of the species. Research and progress made through this project are reported to the U.S. Army Corps of Engineers annually. This annual report details the research effort and progress made by the Comprehensive Sturgeon Research Project during 2011.

  5. Development of conceptual ecological models linking management of the Missouri River to pallid sturgeon population dynamics

    USGS Publications Warehouse

    Jacobson, Robert B.; Parsley, Michael J.; Annis, Mandy L.; Colvin, Michael E.; Welker, Timothy L.; James, Daniel A.

    2015-01-01

    This report documents the process of developing and refining conceptual ecological models (CEMs) for linking river management to pallid sturgeon (Scaphirhynchus albus) population dynamics in the Missouri River. The refined CEMs are being used in the Missouri River Pallid Sturgeon Effects Analysis to organize, document, and formalize an understanding of pallid sturgeon population responses to past and future management alternatives. The general form of the CEMs, represented by a population-level model and component life-stage models, was determined in workshops held in the summer of 2013. Subsequently, the Missouri River Pallid Sturgeon Effects Analysis team designed a general hierarchical structure for the component models, refined the graphical structure, and reconciled variation among the components and between models developed for the upper river (Upper Missouri & Yellowstone Rivers) and the lower river (Missouri River downstream from Gavins Point Dam). Importance scores attributed to the relations between primary biotic characteristics and survival were used to define a candidate set of working dominant hypotheses about pallid sturgeon population dynamics. These CEMs are intended to guide research and adaptive-management actions to benefit pallid sturgeon populations in the Missouri River.

  6. Ecological requirements for pallid sturgeon reproduction and recruitment in the Missouri River—Annual report 2014

    USGS Publications Warehouse

    Delonay, Aaron J.; Chojnacki, Kimberly A.; Jacobson, Robert B.; Braaten, Patrick J.; Buhl, Kevin J.; Elliott, Caroline M.; Erwin, Susannah O.; Faulkner, Jacob D.A.; Candrl, James S.; Fuller, David B.; Backes, Kenneth M.; Haddix, Tyler M.; Rugg, Matthew L.; Wesolek, Christopher J.; Eder, Brandon L.; Mestl, Gerald E.

    2016-03-16

    The Comprehensive Sturgeon Research Project is a multiyear, multiagency collaborative research framework developed to provide information to support pallid sturgeon recovery and Missouri River management decisions. The project strategy integrates field and laboratory studies of sturgeon reproductive ecology, early life history, habitat requirements, and physiology. The project scope of work is developed annually with collaborating research partners and in cooperation with the U.S. Army Corps of Engineers, Missouri River Recovery Program–Integrated Science Program. The project research consists of several interdependent and complementary tasks that involve multiple disciplines.The project research tasks in the 2014 scope of work emphasized understanding of reproductive migrations and spawning of adult pallid sturgeon and hatch and drift of larvae. These tasks were addressed in three hydrologically and geomorphologically distinct parts of the Missouri River Basin: the Lower Missouri River downstream from Gavins Point Dam, the Upper Missouri River downstream from Fort Peck Dam and downstream reaches of the Milk River, and the Lower Yellowstone River. The project research is designed to inform management decisions related to channel re-engineering, flow modification, and pallid sturgeon population augmentation on the Missouri River and throughout the range of the species. Research and progress made through this project are reported to the U.S. Army Corps of Engineers annually. This annual report details the research effort and progress made by the Comprehensive Sturgeon Research Project during 2014.

  7. Ecological requirements for pallid sturgeon reproduction and recruitment in the Missouri River—Annual report 2014

    USGS Publications Warehouse

    Delonay, Aaron J.; Chojnacki, Kimberly A.; Jacobson, Robert B.; Braaten, Patrick J.; Buhl, Kevin J.; Elliott, Caroline M.; Erwin, Susannah O.; Faulkner, Jacob D.A.; Candrl, James S.; Fuller, David B.; Backes, Kenneth M.; Haddix, Tyler M.; Rugg, Matthew L.; Wesolek, Christopher J.; Eder, Brandon L.; Mestl, Gerald E.

    2016-01-01

    The Comprehensive Sturgeon Research Project is a multiyear, multiagency collaborative research framework developed to provide information to support pallid sturgeon recovery and Missouri River management decisions. The project strategy integrates field and laboratory studies of sturgeon reproductive ecology, early life history, habitat requirements, and physiology. The project scope of work is developed annually with collaborating research partners and in cooperation with the U.S. Army Corps of Engineers, Missouri River Recovery Program–Integrated Science Program. The project research consists of several interdependent and complementary tasks that involve multiple disciplines.The project research tasks in the 2014 scope of work emphasized understanding of reproductive migrations and spawning of adult pallid sturgeon and hatch and drift of larvae. These tasks were addressed in three hydrologically and geomorphologically distinct parts of the Missouri River Basin: the Lower Missouri River downstream from Gavins Point Dam, the Upper Missouri River downstream from Fort Peck Dam and downstream reaches of the Milk River, and the Lower Yellowstone River. The project research is designed to inform management decisions related to channel re-engineering, flow modification, and pallid sturgeon population augmentation on the Missouri River and throughout the range of the species. Research and progress made through this project are reported to the U.S. Army Corps of Engineers annually. This annual report details the research effort and progress made by the Comprehensive Sturgeon Research Project during 2014.

  8. Species and hybrid identification of sturgeon caviar: a new molecular approach to detect illegal trade.

    PubMed

    Boscari, E; Barmintseva, A; Pujolar, J M; Doukakis, P; Mugue, N; Congiu, L

    2014-05-01

    Overexploitation of wild populations due to the high economic value of caviar has driven sturgeons to near extinction. The high prices commanded by caviar on world markets have made it a magnet for illegal and fraudulent caviar trade, often involving low-value farmed caviar being sold as top-quality caviar. We present a new molecular approach for the identification of pure sturgeon species and hybrids that are among the most commercialized species in Europe and North America. Our test is based on the discovery of species-specific single nucleotide polymorphisms (SNPs) in the ribosomal protein S7, supplemented with the Vimentin gene and the mitochondrial D-loop. Test validations performed in 702 specimens of target and nontarget sturgeon species demonstrated a 100% identification success for Acipenser naccarii, A. fulvescens, A. stellatus, A. sinensis and A. transmontanus. In addition to species identification, our approach allows the identification of Bester and AL hybrids, two of the most economically important hybrids in the world, with 80% and 100% success, respectively. Moreover, the approach has the potential to identify many other existing sturgeon hybrids. The development of a standardized sturgeon identification tool will directly benefit trade law enforcement, providing the tools to monitor and regulate the legal trade of caviar and protect sturgeon stocks from illicit producers and traders, hence contributing to safeguarding this group of heavily threatened species.

  9. Reconsidering residency: Characterization and conservation implications of complex migratory patterns of shortnose sturgeon (Acispenser brevirostrum)

    USGS Publications Warehouse

    Dionne, Phillip E.; Zydlewski, Gayle B.; Kinnison, Michael T.; Zydlewski, Joseph; Wippelhauser, Gail S.

    2013-01-01

    Efforts to conserve endangered species usually involve attempts to define and manage threats at the appropriate scale of population processes. In some species that scale is localized; in others, dispersal and migration link demic units within larger metapopulations. Current conservation strategies for endangered shortnose sturgeon (Acipenser brevirostrum) assume the species is river resident, with little to no movement between rivers. However we have found that shortnose sturgeon travel more than 130 km through coastal waters between the largest rivers in Maine. Indeed, acoustic telemetry shows that shortnose sturgeon enter six out of the seven acoustically monitored rivers we have monitored, with over 70% of tagged individuals undertaking coastal migrations between river systems. Four migration patterns were identified for shortnose sturgeon inhabiting the Penobscot River, Maine: river resident (28%), spring coastal emigrant (24%), fall coastal emigrant (33%), and summer coastal emigrant (15%). No shortnose sturgeon classified as maturing female exhibited a resident pattern, indicating differential migration. Traditional river-specific assessment and management of shortnose sturgeon could be better characterized using a broader metapopulation scale, at least in the Gulf of Maine, that accounts for diverse migratory strategies and the importance of migratory corridors as critical habitat.

  10. Response of spawning lake sturgeons to change in hydroelectric facility operation

    SciTech Connect

    Auer, N.A.

    1996-01-01

    Spawning of lake sturgeon Acipenser fulvescens was documented from 1987 to 1992 below the Prickett hydroelectric facility on the Sturgeon River, a tributary to Portage Lake, Michigan. Lake sturgeons were captured at the spawning site with dip nets during periods of reduced flow. A change in the spawning characteristics of the population was noted that corresponded to a changed in the operation of the hydroelectric facility. In 1987 and 1988 the facility operated in a peaking mode, which resulted in large daily fluctuations in river flows. The years 1989 and 1990 were years of transition, and in 1991 and 1992 the facility released near run-of-the-river (ROR) flows. Under near-ROR flows, which were more natural, adult lake sturgeons spent 4-6 weeks less at the spawning sites, 74% more fish were observed, weights were greater due to a 68% increase in number of females, and fish had increased reproductive readiness. The change in flow regime was the result of a Federal Energy Regulatory Commission relicensing action. The positive response observed in lake sturgeon spawning activity that resulted from the change of facility operation to near-ROR flows should be beneficial to the survival and perpetuation of this population. Similar results may be experienced in other lake sturgeon waters affected by manipulated flow regimes. 28 refs., 5 figs., 6 tabs.

  11. Effect of exposure of sturgeon roe to low-intensity laser radiation on the hardiness of juvenile sturgeon

    NASA Astrophysics Data System (ADS)

    Plavskiia, V. Yu.; Barulin, N. V.

    2008-03-01

    We present data on the effect of polarized laser radiation in the near IR region of the spectrum with wavelength 808 nm on the resistance of juvenile sturgeon to oxygen deficiency in the habitat when the fertilized roe are briefly exposed to radiation in the organogenesis stage. The magnitude of the stimulating effect depends on the exposure time (t) and power density (P) of the radiation and also on its modulation frequency (F). For optimal irradiation parameters (cw mode, P = 2.9 mW/cm2, t = 60 sec), the hardiness of the juveniles increases by a factor of ˜1.5 compared with the control group. The maximum differences in the sensitivity of embryos to cw and pulsed radiation are observed for F = 1 Hz; as the modulation frequency increases up to F = 50 Hz, the magnitude of the photobiological effect approaches a level typical for cw exposure. We show that the duration of the dark period (pause time) between pulses is the critical parameter determining the dependence of the stimulating effect on the modulation frequency. We discuss questions concerning use of the indicated physical factor in the technology for raising sturgeon under industrial fish farming conditions.

  12. Population viability analysis of the Endangered shortnose sturgeon

    SciTech Connect

    Jager, Yetta; Bevelhimer, Mark S; Peterson, Douglas L.

    2011-07-01

    This study used population viability analysis (PVA) to partition the influences of potential threats to the endangered shortnose sturgeon (Acipenser brevirostrum). A workshop brought together experts to help identify potential threats including groundwater withdrawal, poor water quality, saltwater intrusion, mercury effects, harvest as by-catch, and sedimentation of spawning habitat. During the course of the project, we eliminated some threats and added new ones. Groundwater withdrawal was dismissed after a study failed to identify connection with groundwater and the majority of pumping is from a confined aquifer. We also eliminated activities on Fort Stewart as influences on spawning habitat because any successful spawning must occur upstream of Fort Stewart. We added climate change to the list of threats based on our assessment of temperature effects and expectations of sea-level rise. Our study highlighted the role of populations in nearby rivers in providing metapopulation support, raising the concern that the population in the Ogeechee River acts as a demographic sink. As part of this study, we carried out a field sampling study to analyze effects of training activities on headwater streams. We developed a new methodology for sampling design as part of this effort and used a mixed-modeling approach to identify relationships between land cover-land use, including those associated with military training activity and water quality. We found that tank training was associated with higher suspended sediment and equipment training was associated with higher organic carbon) and water quality. We detected effects of training on suspended sediment and organic carbon. We also carried out a field sampling effort in the Canoochee and Ogeechee Rivers. In the Ogeechee River, we found that dissolved oxygen in 40% of measurements during summer were below 4 mg L-1. To evaluate mercury as a potential threat, we developed a mercury uptake model and analyzed mercury levels in

  13. Linking River Morphology to Larval Drift of an Endangered Sturgeon

    NASA Astrophysics Data System (ADS)

    Bazzetta, L.; Jacobson, R. B.; Braaten, P. J.; Elliott, C. M.; Reuter, J. M.

    2009-12-01

    Computational models developed to calculate longitudinal advection and dispersion of contaminants in rivers have potential application in predicting larval drift. A critical component of this family of models is the longitudinal dispersion coefficient which parameterizes the processes that retain and distribute a contaminant along the river. Here we evaluate the potential for longitudinal dispersion coefficients to characterize larval drift of the endangered pallid sturgeon (Scaphirhynchus albus) in various segments of the free-flowing Missouri River ranging from Missouri to Montana. We randomly selected transects of acoustic Doppler current profiler (ADCP) flow velocity data from reach-scale datasets that were collected in the Missouri River from 2002-2008 under comparable discharge conditions. We used previously developed equations (Kim and others, 2007) to calculate a one-dimensional longitudinal dispersion coefficient for each ADCP transect. We compared the statistical distributions of these coefficients for 2 to 6 reaches chosen from each of six geomorphic segments of the Missouri. Distributional patterns indicate that dispersion coefficients relate to observed variation in hydrology and geomorphology of the channel at the segment scale. Although one-dimensional dispersion analysis demonstrates potential as a tool for estimating pallid sturgeon larval drift and habitat suitability in unchannelized portions of the Missouri River, the large spatial variation in calculated dispersion coefficients resulting from river-training structures (wing dikes) in the Lower Missouri complicates selection of appropriate values. Recent data indicating that pallid sturgeon larvae occur in greater concentration in the thalweg indicate that the majority of larvae may bypass these structures and their associated retentive eddies. A two-dimensional space-averaged dispersion calculation and analysis may more accurately characterize the potential drift times and distances of larval

  14. Allometric relationships of the dentition of the great White Shark, Carcharodon carcharias, in forensic investigations of shark attacks.

    PubMed

    Nambiar, P; Bridges, T E; Brown, K A

    1991-06-01

    As a result of a systematic morphometric study of shark dentitions, a system of notation for describing the location of shark teeth has been developed and is proposed as a standard to be adopted for use in similar studies in the future. The macroscopic morphology of White Shark teeth has been characterised in order to gain quantitative data which might assist in identification of these sharks from bite marks on victims or objects or from shark carcasses. Using these data, a nomogram has been developed which can be used to estimate the body length of a White Shark from measurements of tooth or bite mark morphology. An example of the forensic application of such allometric data is provided as it applied to a recent fatal attack on a diver by a White Shark.

  15. Reintroduction of lake sturgeon in the St. Louis River, western Lake Superior

    USGS Publications Warehouse

    Schram, Stephen T.; Lindgren, John; Evrard, Lori M.

    1999-01-01

    Lake sturgeon Acipenser fulvescens declined in abundance in Lake Superior's St. Louis River during the late 1800s and were eliminated from the river during the early 1900s because of the combined effects of exploitation, pollution, and habitat alteration. Since then, exploitation in the river and in Lake Superior has been reduced. Furthermore, water quality in the St. Louis River has improved, and its upper-estuary spawning habitat has remained relatively unchanged and adequate. Lake sturgeon have been stocked annually in the St. Louis River since 1983; from 1983 to 1994 stockings included 736,000 fry, 128,000 fingerlings, and 500 yearlings of the Lake Winnebago strain. Relative abundance, distribution, and growth were determined by sampling marked fish in the St. Louis River estuary and western Lake Superior with graded-mesh gill nets and bottom trawls. During 1983–1998, 644 lake sturgeon were caught in 15,486 m of gill net, and 196 were caught in 1,200 trawl tows. Lake sturgeon were sampled most frequently near channelized portions of the St. Louis River and stayed in the estuary up to 5 years before entering Lake Superior. Lake sturgeon were not captured in western Lake Superior prior to stocking, but abundance increased dramatically after 1985. Of 582 lake sturgeon sampled along the Wisconsin shore of Lake Superior from 1985 through 1998 (347,000 m of gill nets), 93% were captured in less than 30 m of water. A total of 93 lake sturgeon were reported from assessment netting conducted along the Minnesota shore of Lake Superior from 1992 through 1997. The current range of stocked lake sturgeon extends from the St. Louis River 145 km east to the apostle Islands in Wisconsin and 110 km northeast to Little Marais in Minnesota. Increases in lake sturgeon abundance were directly attributed to the stocking program. We recommend stocking a minimum of 20 year-classes and the use of a Lake Superior egg source, if possible. Final evaluation of the project will be

  16. Identification of plasma glucocorticoids in pallid sturgeon in response to stress

    USGS Publications Warehouse

    Webb, M.A.H.; Allert, J.A.; Kappenman, K.M.; Marcos, J.; Feist, G.W.; Schreck, C.B.; Shackleton, C.H.

    2007-01-01

    Compared to teleosts, little is known about the stress response in chondrosteans, and the glucocorticoid(s) most responsive to stress have never been definitively determined in sturgeon. In terms of cortisol production, pallid sturgeon (Scaphirhynchus albus) have a low physiological response to stress compared to other sturgeons (Acipenser sp.). Because of this, our null hypothesis was that cortisol is not the predominant glucocorticoid secreted in response to stress in pallid sturgeon. Our objective was to identify the putative glucocorticoids present in the plasma of pallid sturgeon during the stress response. Pallid sturgeon were subjected to a severe confinement stress (12 h) with an additional handling stressor for the first 6 h. Control fish were not subjected to confinement but were handled only to collect blood. Blood plasma was collected at time 0, 6, and 12 h. Gas chromatography/mass spectrometry was used to screen the plasma for the spectrum of glucocorticoids and determine the putative steroid secreted during the stress response. Cortisol was the primary glucocorticoid detected in stressed pallid sturgeon. In addition, the cortisol metabolites cortisone, alloTHE (5??-pregnane-3??,17??,21-triol-11,20-dione), allo-??-cortolone (3??,17??,20??,21-tetrahydro-5??-pregnan-11-one), and allo-??-cortolone (3??,17??,20??,21-tetrahydro-5??-pregnan-11-one) were detected. Plasma cortisol increased from a resting concentration of 0.67 ng/ml to 10.66 ng/ml at 6 h followed by a decrease to 6.78 ng/ml by 12 h. Plasma glucose increased significantly by time 6 and 12 h in both stressed and unstressed groups and remained elevated at time 12 h, while resting lactate concentrations were low to non-detectable and did not increase significantly with the stressor over time. Cortisol was the primary glucocorticoid synthesized and secreted in response to a stressor in pallid sturgeon. Though the proportional increase in plasma cortisol in stressed pallid sturgeon was lower than

  17. Habitat and movement of lake sturgeon in the upper Mississippi River system, USA

    USGS Publications Warehouse

    Knights, Brent C.; Vallazza, Jonathon M.; Zigler, Steven J.; Dewey, Michael R.

    2002-01-01

    Lake sturgeon Acipenser fluvescens, which are now protected from harvest, are considered rare in the upper Mississippi River and little information is available on the remaining populations. Transmitters were implanted into 31 lake sturgeon from two sites in the upper Mississippi River to describe their habitats and movement. The areas surrounding the tagging sites were core areas for both groups of lake sturgeon based on the high use (about 50% of locations by group) and frequent return to these areas by many of the tagged fish. Core areas contained sites with unique hydraulic characteristics, such that depositional substrates were common yet flow was present; these areas probably provide important feeding habitat for lake sturgeon. Minimal geographical overlap in range occurred between groups, suggesting that river reaches and associated core areas were unique to groups or substocks of fish. Lake sturgeon exhibited complex movement behaviors and had ranges of 3-198 km (median, 56 km) during the study. Tagged fish moved both downstream and upstream through upper Mississippi River navigation dams. However, dams appeared to be intermittent barriers to upstream passage because upstream passage events (10 fish, 19 passages) were fewer than downstream events (13 fish, 35 passages). Extensive use of the Wisconsin River by one group of lake sturgeon tagged in the upper Mississippi River has implications regarding management of a threatened population that transcends regulatory boundaries. Our study indicates that lake sturgeon In the upper Mississippi River system share many movement and habitat use characteristics with populations in other systems. However, significant data gaps preclude development of cogent management strategies, including information on population numbers and dynamics, identification of spawning areas, relations between groups, and assessment of the effects of commercial navigation.

  18. Dietary calcein marking of shovelnose sturgeon and the effect of sunlight on mark retention

    USGS Publications Warehouse

    Honeyfield, D.C.; Kindschi, G.A.; Bell, T.A.; Mohler, J.W.

    2011-01-01

    Calcein, a fluorochrome dye, is a potential fish-marking agent that has not been evaluated in sturgeon. Shovelnose sturgeon Scaphirhynchus platorynchus (average weight, 9.7 g) were fed calcein, immersed in a calcein bath, or left unmarked to determine calcein mark intensity. In the first study, six treatments were evaluated in a two-by-three factorial arrangement. Feed was formulated with 2.0 g of SE-MARK/kg either as powder or in an encapsulated form. Sturgeon were fed the test diets for 5, 10, or 15 d. They readily ate feed containing powdered or encapsulated calcein. Sturgeon fed powdered calcein had more brilliant marks than those fed encapsulated calcein (8.27 versus 4.66 lm; P < 0.03) 6 months postexposure. Fish fed calcein for 15 d (11.26 lm) were more brilliant (P < 0.002) than fish fed for either 5 d (3.02 lm) or 10 d (5.11 lm). Post hoc comparison of the three treatment groups showed that sturgeon fed powdered calcein for 15 d (14.06 lm) were brighter (P < 0.01) than fish fed encapsulated calcein (8.46 lm) or fish immersed in calcein (9.68 lm). In the second study, previouslymarked sturgeon were exposed to sunlight for 14months to determine their retention of calcein marks. Dorsal marks were no longer visible on fish exposed to 100% sunlight after 8 weeks. Most but not all fish exposed to 20% sunlight had no discernable dorsalmarks after 8 weeks, but ventral marks at the pectoral fin girdle were present on all fish in the 0% and 20% sunlight exposure treatments. Feeding calcein for 15 d appears to have excellent potential for practical application, such as distinguishing hatchery-reared from wild fish. Ventral calcein marks remained visible after 14 months of exposure to 20% sunlight when sturgeon were reared in clear water. ?? American Fisheries Society 2011.

  19. Water-quality requirements, tolerances, and preferences of pallid sturgeon (Scaphirhynchus albus) in the lower Missouri River

    USGS Publications Warehouse

    Blevins, Dale W.

    2011-01-01

    Additional research could be used to characterize and quantify the requirements, tolerance, and preferences of pallid sturgeon to these water-quality characteristics, especially during the egg and larval life stages. Enhancements to existing water-sampling programs are needed to quantify the exposure of pallid sturgeon to many of these water-quality stressors.

  20. Comparison of select hematology and serum chemistry analtyes between wild-caught and aquarium-housed lake sturgeon (Acipenser fulvescens)

    USGS Publications Warehouse

    DiVincenti, Louis; Priest, Heather; Walker, Kyle J.; Wyatt, Jeffrey D.; Dittman, Dawn

    2013-01-01

    Hematology and serum chemistry analytes were compared between wild-caught and aquarium-housed lake sturgeon (Acipenser fulvescens) to potentially improve understanding of medical issues in lake sturgeon. Blood samples were taken from 30 lake sturgeon exhibited in 11 institutions in the United States and from 23 experimentally stocked lake sturgeon caught in gill nets in the lower Genesee River in Rochester, New York, USA. For hematology, only segmented neutrophil count was significantly different, with wild-caught fish having a higher number of circulating neutrophils. For clinical chemistry analytes, chloride, uric acid, calcium, phosphate, glucose, aspartate aminotransferase, triglycerides, and creatine kinase were significantly different between the two cohorts. These differences are likely not clinically significant and are attributable to handling stress, variability in environmental parameters, or differences in nutritional status. This is the first report of hematology and serum chemistry values in aquarium-housed lake sturgeon and provides useful reference intervals for clinicians.

  1. Avoidance of Pile-Driving Noise by Hudson River Sturgeon During Construction of the New NY Bridge at Tappan Zee.

    PubMed

    Krebs, Justin; Jacobs, Fred; Popper, Arthur N

    2016-01-01

    Sturgeon movements were monitored during a pile-driving operation. Fewer sturgeon were detected during pile driving and remained for a shorter time than during silent control periods. Moreover, the short time spent by sturgeon near pile driving suggests that they were unlikely to have reached the criterion of 187 dB re 1 μPa(2)·s cumulative sound exposure level. These results suggest that sturgeon are likely to avoid impact pile driving and not remain long enough to experience physiological effects, thus providing empirical evidence that the 206 dB re 1 μPa peak sound pressure level is the appropriate criterion for assessing the impacts of pile-driving noise on sturgeon.

  2. Comparison of select hematology and serum chemistry analtyes between wild-caught and aquarium-housed lake sturgeon (Acipenser fulvescens).

    PubMed

    DiVincenti, Louis; Priest, Heather; Walker, Kyle J; Wyatt, Jeffrey D; Dittman, Dawn

    2013-12-01

    Hematology and serum chemistry analytes were compared between wild-caught and aquarium-housed lake sturgeon (Acipenser fulvescens) to potentially improve understanding of medical issues in lake sturgeon. Blood samples were taken from 30 lake sturgeon exhibited in 11 institutions in the United States and from 23 experimentally stocked lake sturgeon caught in gill nets in the lower Genesee River in Rochester, New York, USA. For hematology, only segmented neutrophil count was significantly different, with wild-caught fish having a higher number of circulating neutrophils. For clinical chemistry analytes, chloride, uric acid, calcium, phosphate, glucose, aspartate aminotransferase, triglycerides, and creatine kinase were significantly different between the two cohorts. These differences are likely not clinically significant and are attributable to handling stress, variability in environmental parameters, or differences in nutritional status. This is the first report of hematology and serum chemistry values in aquarium-housed lake sturgeon and provides useful reference intervals for clinicians.

  3. Investigating the capability to resolve complex white matter structures with high b-value diffusion magnetic resonance imaging on the MGH-USC Connectom scanner.

    PubMed

    Fan, Qiuyun; Nummenmaa, Aapo; Witzel, Thomas; Zanzonico, Roberta; Keil, Boris; Cauley, Stephen; Polimeni, Jonathan R; Tisdall, Dylan; Van Dijk, Koene R A; Buckner, Randy L; Wedeen, Van J; Rosen, Bruce R; Wald, Lawrence L

    2014-11-01

    One of the major goals of the NIH Blueprint Human Connectome Project was to map and quantify the white matter connections in the brain using diffusion tractography. Given the prevalence of complex white matter structures, the capability of resolving local white matter geometries with multiple crossings in the diffusion magnetic resonance imaging (dMRI) data is critical. Increasing b-value has been suggested for delineation of the finer details of the orientation distribution function (ODF). Although increased gradient strength and duration increase sensitivity to highly restricted intra-axonal water, gradient strength limitations require longer echo times (TE) to accommodate the increased diffusion encoding times needed to achieve a higher b-value, exponentially lowering the signal-to-noise ratio of the acquisition. To mitigate this effect, the MGH-USC Connectom scanner was built with 300 mT/m gradients, which can significantly reduce the TE of high b-value diffusion imaging. Here we report comparisons performed across b-values based on q-ball ODF metrics to investigate whether high b-value diffusion imaging on the Connectom scanner can improve resolving complex white matter structures. The q-ball ODF features became sharper as the b-value increased, with increased power fraction in higher order spherical harmonic series of the ODF and increased peak heights relative to the overall size of the ODF. Crossing structures were detected in an increasingly larger fraction of white matter voxels and the spatial distribution of two-way and three-way crossing structures was largely consistent with known anatomy. Results indicate that dMRI with high diffusion encoding on the Connectom system is a promising tool to better characterize, and ultimately understand, the underlying structural organization and motifs in the human brain.

  4. Investigating the Capability to Resolve Complex White Matter Structures with High b-Value Diffusion Magnetic Resonance Imaging on the MGH-USC Connectom Scanner

    PubMed Central

    Nummenmaa, Aapo; Witzel, Thomas; Zanzonico, Roberta; Keil, Boris; Cauley, Stephen; Polimeni, Jonathan R.; Tisdall, Dylan; Van Dijk, Koene R.A.; Buckner, Randy L.; Wedeen, Van J.; Rosen, Bruce R.; Wald, Lawrence L.

    2014-01-01

    Abstract One of the major goals of the NIH Blueprint Human Connectome Project was to map and quantify the white matter connections in the brain using diffusion tractography. Given the prevalence of complex white matter structures, the capability of resolving local white matter geometries with multiple crossings in the diffusion magnetic resonance imaging (dMRI) data is critical. Increasing b-value has been suggested for delineation of the finer details of the orientation distribution function (ODF). Although increased gradient strength and duration increase sensitivity to highly restricted intra-axonal water, gradient strength limitations require longer echo times (TE) to accommodate the increased diffusion encoding times needed to achieve a higher b-value, exponentially lowering the signal-to-noise ratio of the acquisition. To mitigate this effect, the MGH-USC Connectom scanner was built with 300 mT/m gradients, which can significantly reduce the TE of high b-value diffusion imaging. Here we report comparisons performed across b-values based on q-ball ODF metrics to investigate whether high b-value diffusion imaging on the Connectom scanner can improve resolving complex white matter structures. The q-ball ODF features became sharper as the b-value increased, with increased power fraction in higher order spherical harmonic series of the ODF and increased peak heights relative to the overall size of the ODF. Crossing structures were detected in an increasingly larger fraction of white matter voxels and the spatial distribution of two-way and three-way crossing structures was largely consistent with known anatomy. Results indicate that dMRI with high diffusion encoding on the Connectom system is a promising tool to better characterize, and ultimately understand, the underlying structural organization and motifs in the human brain. PMID:25287963

  5. Age estimation for shovelnose sturgeon: A cautionary note based on annulus formation in pectoral fin rays

    USGS Publications Warehouse

    Whiteman, K.W.; Travnichek, V.H.; Wildhaber, M.L.; DeLonay, A.; Papoulias, D.; Tillett, D.

    2004-01-01

    Numerous studies have examined the age and growth of shovelnose sturgeon Scaphirhynchus platorynchus, but only one study attempted to validate age estimation techniques. Therefore, our objective was to use marginal increment analysis to validate annulus formation in pectoral fin rays of shovelnose sturgeon collected from the Missouri River. We also compared the precision of age estimates between two different readers. Marginal increment distance indicated that for most of the populations an opaque band was laid down in pectoral fin rays during the summer. However, opaque bands were formed throughout the year in some individuals, which could be problematic when using fin rays for age estimation. The agreement of age estimates by two readers for shovelnose sturgeon was only 18%, and differences in ages between the two readers increased for older fish. The presence of split annuli, false annuli, spawning bands, imbedded rays, and deteriorating sections made individual growth rings difficult to separate. Our findings verified that opaque bands are formed annually during the summer in the pectoral fin rays of most shovelnose sturgeon, but some individuals form opaque bands during other times. Pectoral fin rays will probably continue to be the most practical method of age estimation in shovelnose sturgeon, but ages estimated by this method should be used with caution.

  6. Sturgeon and Paddlefish Saggital Otoliths are Comprised of the Calcium Carbonate Polymorphs Vaterite and Calcite

    DOE PAGESBeta

    Prachell, B. M.; Chakoumakos, Bryan C.; Feygenson, Mikhail; Whitledge, Gregory; Koenigs, Ryan; Bruch, Ronald

    2016-07-27

    The otoliths of modern fishes are most commonly comprised of the metastable aragonite polymorph of calcium carbonate (CaCO3); however, sturgeons have otoliths reportedly comprised of the least stable of the three most-common polymorphs, vaterite. In this study, we used neutron diffraction to characterize CaCO3 polymorph composition of lake sturgeon and paddlefish otoliths. Based on previous summaries of CaCO3 composition over fish evolutionary history, we hypothesized that sturgeon and paddlefish otoliths would have similar polymorph composition. We found that despite previous reports of sturgeon otoliths being comprised entirely of vaterite, that all otoliths we examined in this study also had amore » calcite fraction that ranged from 17.9+ 6.0 wt. % to 35.9 + 2.9 wt. %. We also conducted a grinding experiment that demonstrated that calcite fractions were due to biological variation and not an artifact of polymorph transformation during preparation. Our study provides the initial characterization of the polymorph composition of the otoliths of lake sturgeon, and paddlefish and also provides the first-ever report of otoliths of Acipenserids as having a calcite fraction.« less

  7. Lake Sturgeon, Acipenser fulvescens, movements in Rainy Lake, Minnesota and Ontario

    USGS Publications Warehouse

    Adams, W.E.; Kallemeyn, L.W.; Willis, D.W.

    2006-01-01

    Rainy Lake, Minnesota-Ontario, contains a native population of Lake Sturgeon (Acipenser fulvescens) that has gone largely unstudied. The objective of this descriptive study was to summarize generalized Lake Sturgeon movement patterns through the use of biotelemetry. Telemetry data reinforced the high utilization of the Squirrel Falls geographic location by Lake Sturgeon, with 37% of the re-locations occurring in that area. Other spring aggregations occurred in areas associated with Kettle Falls, the Pipestone River, and the Rat River, which could indicate spawning activity. Movement of Lake Sturgeon between the Seine River and the South Arm of Rainy Lake indicates the likelihood of one integrated population on the east end of the South Arm. The lack of re-locations in the Seine River during the months of September and October may have been due to Lake Sturgeon moving into deeper water areas of the Seine River and out of the range of radio telemetry gear or simply moving back into the South Arm. Due to the movements between Minnesota and Ontario, coordination of management efforts among provincial, state, and federal agencies will be important.

  8. Investigating variation in the nutritional ecology and genetics of White-tailed Ptarmigan: implications for climate change

    NASA Astrophysics Data System (ADS)

    Oyler-McCance, S. J.; Stricker, C. A.; Braun, C. E.; Wann, G. T.; Aldridge, C. L.

    2010-12-01

    White-tailed Ptarmigan (Lagopus leucura) are well suited as a focal species for the study of climate change because they are adapted to cool, alpine environments that are expected to undergo unusually rapid climate change. We compared samples collected in the late 1930s, the late 1960s, and the late 2000s using molecular genetic and stable isotope methods in an effort to determine whether White-tailed Ptarmigan on Mt. Evans, Colorado have experienced recent environmental changes resulting in shifts in genetic diversity, gene frequency, and nutritional ecology. We genotyped 115 individuals spanning the three time periods using nine polymorphic microsatellite loci in our genetic analysis. These samples were also analyzed for stable carbon and nitrogen isotopic composition. We found a slight trend of lower heterozygosity through time and allelic richness values were lower in more recent times. We found no changes in allele frequencies across time periods suggesting that population sizes have not changed dramatically. Feather δ13C and δ15N values decreased significantly across time periods, whereas the range in isotope values increased consistently from the late 1930s to the later time periods. Inferred changes in the nutritional ecology of White-tailed Ptarmigan on Mt. Evans relates primarily to increased atmospheric deposition of nutrients that likely influenced foraging habits and tundra plant composition and nutritional quality. We briefly discuss similar ongoing work on the neighboring population in Rocky Mountain National Park, Colorado and tie in genetic results from across the species range.

  9. Juvenile pallid (Scaphirhynchus albus) and hybrid pallidxshovelnose (S. albusxplatorynchus) sturgeons exhibit low physiological responses to acute handling and severe confinement.

    PubMed

    Barton, B A; Bollig, H; Hauskins, B L; Jansen, C R

    2000-05-01

    Following a 7.5-h transport haul, juvenile pallid sturgeon (Scaphirhynchus albus) showed a small but significant increase in plasma cortisol to 4.7 ng ml(-1) but similar increases did not occur after fish were handled in a net held in the air for 30 s. Subsequent experiments on yearling pallid sturgeon and hybrid pallidxshovelnose (S. albusxplatorynchus) sturgeon using the same 30-s handling stressor failed to evoke increases in plasma cortisol, lactate or glucose. Plasma cortisol increased significantly from about 2 to 13-14 ng ml(-1) in both pallid and hybrid sturgeon during a 6-h severe confinement stressor with handling. Plasma cortisol in 2-year-old pallid sturgeon subjected to the same stressor demonstrated a linear pattern of increase during the initial 1 h. Plasma lactate increased from 1.11 to about 2.11 mmol l(-1) in hybrid sturgeon during the first hour of severe confinement but did not change throughout the entire confinement period in pallid sturgeon. A significant increase in plasma cortisol to 5.4 ng ml(-1) in 2-year-old pallid sturgeon 1 h after being subjected to 30 s handling at 19:00 h but not at 07:00 or 13:00 h suggests that a small diurnal variation in their stress response may exist. Although both pallid and hybrid sturgeons were responsive to stress, they exhibited very low physiological responses compared with those following equivalent stressors in most teleostean fishes or another chondrostean, the paddlefish (Polyodon spathula). Reasons for the apparent low responses to handling and confinement in scaphirhynchid sturgeons are not known but may relate to their evolutionary history, neuroendocrine mechanisms involved in their corticosteroid responses, or anatomy of their interrenal tissue structure.

  10. Bioaccumulation of Cd, Pb and Zn in the edible and inedible tissues of three sturgeon species in the Iranian coastline of the Caspian Sea.

    PubMed

    Mashroofeh, Abdulreza; Bakhtiari, Alireza Riyahi; Pourkazemi, Mohammad; Rasouli, Sana

    2013-01-01

    The accumulations of Cd, Pb and Zn were determined in edible and inedible tissues of Persian sturgeon (Acipenser persicus; n=27), stellate sturgeon (Acipenser stellatus; n=5) and beluga (Huso huso; n=4) collected from coastal waters of the South Caspian Sea from March to April 2011. Concentrations of metals evaluated in the caviar, muscle, liver, kidney, gills, ovary and heart of the three species of sturgeons have been assessed using the flame and graphite furnace atomic absorption spectrophotometer. Concentrations of Zn, Pb and Cd in the edible and inedible tissues were apparently different among the three species of sturgeons. Especially, beluga heart showed the highest concentrations of Zn and Pb and Cd in Persian sturgeon liver. The analyzed metals were found in the caviar and muscle samples of Persian sturgeon and likewise muscle samples two other sturgeon species at mean concentrations under the permissible limits proposed by MAFF (2000).

  11. Investigating the correlation between white matter and microvasculature changes in aging using large scale optical coherence tomography and confocal fluorescence imaging combined with tissue sectioning

    NASA Astrophysics Data System (ADS)

    Castonguay, Alexandre; Avti, Pramod K.; Moeini, Mohammad; Pouliot, Philippe; Tabatabaei, Maryam S.; Bélanger, Samuel; Lesage, Frédéric

    2015-03-01

    Here, we present a serial OCT/confocal scanner for histological study of the mouse brain. Three axis linear stages combined with a sectioning vibratome allows to cut thru the entire biological tissue and to image every section at a microscopic resolution. After acquisition, each OCT volume and confocal image is re-stitched with adjacent acquisitions to obtain a reconstructed, digital volume of the imaged tissue. This imaging platform was used to investigate correlations between white matter and microvasculature changes in aging mice. Three age groups were used in this study (4, 12, 24 months). At sacrifice, mice were transcardially perfused with a FITC containing gel. The dual imaging capability of the system allowed to reveal different contrast information: OCT imaging reveals changes in refractive indices giving contrast between white and grey matter in the mouse brain, while transcardial perfusion of a FITC shows microsvasculature in the brain with confocal imaging.

  12. Ultrastructural study on the fertilisation process in sturgeon (Acipenser), function of acrosome and prevention of polyspermy.

    PubMed

    Psenicka, Martin; Rodina, Marek; Linhart, Otomar

    2010-01-01

    Sturgeon gametes differ from other fish in that their spermatozoa possess acrosome with finger-like posterolateral projections, which undergo exocytosis and filament formation, whereas eggs possess numerous micropyles. The fertilisation process in Acipenser baerii was investigated by fluorescence and electron microscopy. A suitable activation solution containing 2.5 mM CaCl(2), 15 mM Tris, pH 10 was found for detailed description of acrosomal reaction. The acrosome reaction includes the formation of a spear-like fertilisation filament coming from three endonuclear canals and implantation fossa through the acrosomes. It can accelerate the process of polyspermy prevention. Another unique feature of the acrosome was an anchor-like opening of the posterolateral projections. Mature eggs of A. baerii possessed 2-10 micropyles in the animal pole region. The eggs consisted of three principal layers and an outermost jelly coat blocking micropyle, and a layer of cortical granules in unfertilised eggs. With the exposure to freshwater, the jelly like layer separated from the egg surface, whereas the cortical granules swelled. No change between the layers of fertilised and unfertilised eggs, apart from the generation of an increasing perivitelline space by dissolution of the cortical granules, had been observed after the fusion of spermatozoon with an egg. A fertilisation cone blocked a fusion of other spermatozoa with cytoplasmatic projection in the fertilised micropyle.

  13. Biochemical characterization of hemoglobins from Caspian Sea sturgeons (Acipenser persicus and Acipenser stellatus).

    PubMed

    Ariaeenejad, Shohreh; Habibi-Rezaei, Mehran; Jamili, Shahla; Fatemi, Mohammad Reza; Poursasan, Najmeh; Ahmad, Faizan; Sheibani, Nader; Kavousi, Kaveh; Moosavi-Movahedi, Ali A

    2012-01-01

    Hemoglobin (Hb) variability is a commonly used index of phylogenetic differentiation and molecular adaptation in fish enabling them to adapt to different ecological conditions. In this study, the characteristics of Hbs from two Sturgeon species of the Southern Caspian Sea Basin were investigated. After extraction and separation of hemoglobin from whole blood, the polyacrylamide gel electrophoresis (SDS-PAGE), cellulose acetate electrophoresis, and isoelectric focusing (IEF) were used to confirm Hb variabilities in these fishes. We showed that although both species have variable Hbs with different isoelectric points, their dominant Hbs can be identified. Ion exchange on CM-cellulose chromatography was used for purification of the dominant Hbs from these fishes. The accuracy of the methods was confirmed by IEF and SDS-PAGE. Spectral studies using fluorescence spectrophotometery indicated that although the Hbs from these fishes had similar properties they exhibited clear differences with human Hb. A comparative study of Hbs alpha-helix secondary substructures was performed by circular dichroism spectropolarimetry (CD) analysis. UV-vis spectrophotometery was also utilized to measure oxygen affinity of Hbs by sodium dithionite. Oxygen affinities of these Hbs were compared using Hb-oxygen dissociation curves. Together, these results demonstrate a significant relationship between oxygen affinity of fish hemoglobins and environmental partial pressure of oxygen.

  14. Pathologic and physiologic effects associated with long-term intracoelomic transmitters in captive Siberian sturgeon

    USGS Publications Warehouse

    Boone, S. Shaun; Divers, Stephen J.; Camus, Alvin C.; Peterson, Douglas C.; Jennings, Cecil A.; Shelton, James L.; Hernandez, Sonia M.

    2015-01-01

    Intracoelomic transmitters are commonly used to evaluate migratory patterns, distribution, and habitat use of many species of fish. Currently, transmitter implantation relies mostly on the assumption that transmitters do not cause any adverse physiological or pathological effects on the animal. To investigate these effects, we surgically implanted 60 Siberian Sturgeon Acipenser baeri with transmitters that weighed less than 2% of their body weight. Postoperative assessments were conducted at 1, 2, 8, 12, 26, and 55 weeks to evaluate surgical healing and transmitter retention. Blood samples were collected before and after the 55-week study for serum cortisol analysis. Overall transmitter loss was 32%. Minor to moderate adhesions were noted at necropsy but did not appear to affect organ function. One fish was noted to have an intraintestinal transmitter at necropsy, but the fish was in overall good health. Long-term transmitter presence does not appear to increase serum cortisol levels or affect overall growth more than nontransmitter fish. Although long-term telemetry studies can be undertaken with minimal concern for negative physiological or pathological effects from transmitters, researchers should be aware that transmitter loss rates may be higher than previously thought. Mechanisms for transmitter loss may include expulsion through the surgical incision, expulsion through the mucocutaneous junction between the large intestine and the vent, or intraintestinal capture and expulsion through the vent. Received February 10, 2013; accepted June 10, 2013

  15. Cryopreservation of Persian sturgeon (Acipenser persicus) embryos by DMSO-based vitrificant solutions.

    PubMed

    Keivanloo, Saeide; Sudagar, Mohammad

    2016-03-15

    Vitrification could provide a promising tool for the cryopreservation of fish embryos. To achieve successful cryopreservation, several parameters should be taken into account in the design of a vitrification protocol. In the present study, some relevant factors were investigated (choice of a proper vitrificant solutions and temperature for thawing) using neurulation-stage embryos. Six DMSO-based vitrificant solutions (V1-V6) were tested using a 6-step incorporation protocol. DMSO-based vitrificant solutions contained DMSO + permeable cryoprotectants + nonpermeable cryoprotectants. Embryos were immersed in vitrificant solutions for 7 minutes and directly plunged into liquid nitrogen. After vitrification (-196 °C for 10 minutes), the thawing was performed in a water bath at 0 or 20 °C and then embryos incubated until hatched. Our results demonstrated that some embryos vitrified in 5 of 6 vitrification solutions survived and hatched out, but none survived after vitrification in V2. The highest survival rate (45.45%) was observed in samples frozen with the best vitrificant solution (V6) and thawing combination (20 °C). These results establish that cryopreservation of Persian sturgeon (Acipenser persicus) embryos by DMSO-based vitrificant solutions is possible.

  16. Ecological Requirements for Pallid Sturgeon Reproduction and Recruitment in the Lower Missouri River: A Research Synthesis 2005-08

    USGS Publications Warehouse

    DeLonay, Aaron J.; Jacobson, Robert B.; Papoulias, Diana M.; Simpkins, Darin G.; Wildhaber, Mark L.; Reuter, Joanna M.; Bonnot, Tom W.; Chojnacki, Kimberly A.; Korschgen, Carl E.; Mestl, Gerald E.; Mac, Michael J.

    2009-01-01

    This report provides a synthesis of results obtained between 2005 and 2008 from the Comprehensive Sturgeon Research Program, an interagency collaboration between the U.S. Geological Survey, Nebraska Game and Parks Commission, U.S. Fish and Wildlife Service, and the U.S. Army Corps of Engineers' Missouri River Recovery - Integrated Science Program. The goal of the Comprehensive Sturgeon Research Program is to improve fundamental understanding of reproductive ecology of the pallid sturgeon with the intent that improved understanding will inform river and species management decisions. Specific objectives include: *Determining movement, habitat-use, and reproductive behavior of pallid sturgeon; *Understanding reproductive physiology of pallid sturgeon and relations to environmental conditions; *Determining origin, transport, and fate of drifting pallid sturgeon larvae, and evaluating bottlenecks for recruitment of early life stages; *Quantifying availability and dynamics of aquatic habitats needed by pallid sturgeon for all life stages; and *Managing databases, integrating understanding, and publishing relevant information into the public domain. Management actions to increase reproductive success and survival of pallid sturgeon in the Lower Missouri River have been focused on flow regime, channel morphology, and propagation. Integration of 2005-08 Comprehensive Sturgeon Research Program research provides insight into linkages among flow regime, re-engineered channel morphology, and pallid sturgeon reproduction and survival. The research approach of the Comprehensive Sturgeon Research Program integrates opportunistic field studies, field-based experiments, and controlled laboratory studies. The field study plan is designed to explore the role of flow regime and associated environmental cues using two complementary approaches. An upstream-downstream approach compares sturgeon reproductive behavior between an upstream section of the Lower Missouri River with highly

  17. Lake sturgeon response to a spawning reef constructed in the Detroit river

    USGS Publications Warehouse

    Roseman, Edward F.; Manny, B.; Boase, J.; Child, M.; Kennedy, G.; Craig, J.; Soper, K.; Drouin, R.

    2011-01-01

    Prior to the First World War, the bi-national Detroit River provided vast areas of functional fish spawning and nursery habitat. However, ongoing conflicting human uses of these waters for activities such as waste disposal, water withdrawals, shoreline development, shipping, recreation, and fishing have altered many of the chemical, physical, and biological processes of the Detroit River. Of particular interest and concern to resource managers and stakeholders is the significant loss and impairment of fish spawning and nursery habitat that led to the decline in abundance of most fish species using this ecosystem. Lake sturgeon (Acipenser fulvescens) populations for example, were nearly extirpated by the middle of the 20th century, leaving only a small fraction of their former population. Fisheries managers recognized that the loss of suitable fish spawning habitat is a limiting factor in lake sturgeon population rehabilitation in the Detroit River. In efforts to remediate this beneficial water use impairment, a reef consisting of a mixture of natural rock and limestone was constructed at the upstream end of Fighting Island in 2008. This paper focuses on the response by lake sturgeon to the different replicates of suitable natural materials used to construct the fish spawning habitat at Fighting Island in the Detroit River. Pre-construction fisheries assessment during 2006–2008 showed that along with the presence of adult lake sturgeon, spawning conditions were favorable. However, no eggs were found in assessments conducted prior to reef construction. The 3300 m2 Fighting Island reef was placed at the upstream end of the island in October of 2008. The construction design included 12 spawning beds of three replicates each consisting of either round rock, small or large (shot-rock) diameter limestone or a mixture thereof. An observed response by spawning lake sturgeon occurred the following year when spawning-ready adults (ripe), viable eggs, and larvae were

  18. Ecological requirements for pallid sturgeon reproduction and recruitment in the Missouri River—Annual report 2013

    USGS Publications Warehouse

    Delonay, Aaron J.; Jacobson, Robert B.; Chojnacki, Kimberly A.; Braaten, Patrick J.; Buhl, Kevin J.; Eder, Brandon L; Elliott, Caroline M.; Erwin, Susannah O.; Fuller, David B.; Haddix, Tyler M.; Ladd, Hallie L.A.; Mestl, Gerald E.; Papoulias, Diana M.; Rhoten, Jason C.; Wesolek, Christopher J.; Wildhaber, Mark L.

    2016-01-20

    The research tasks in the 2013 scope of work emphasized understanding reproductive migrations and spawning of adult pallid sturgeon, and hatch and drift of free embryos and larvae. These tasks were addressed in four study sections located in three hydrologically and geomorphologically distinct parts of the Missouri River Basin: the Upper Missouri River downstream from Fort Peck Dam, including downstream reaches of the Milk River, the Lower Yellowstone River, and the Lower Missouri River downstream from Gavins Point Dam. The research is designed to inform management decisions related to channel re-engineering, flow modification, and pallid sturgeon population augmentation on the Missouri River, and throughout the range of the species. Research and progress made through this project are reported to the U.S. Army Corps of Engineers annually. This annual report details the research effort and progress made by the Comprehensive Sturgeon Research Project during 2013.

  19. Overview of biology and aquaculture of Amur sturgeon (Acipenser schrenckii) in China

    USGS Publications Warehouse

    Zhuang, P.; Kynard, B.; Zhang, L.; Zhang, T.; Zhang, Z.; Li, D.

    2002-01-01

    Amur sturgeon, Acipenser schrenckii is a large riverine species (max. 3 m length and 190 kg weight) native to the Amur River. In the middle Amur River, males first spawn at 7-8 years of age and females at 9-10 years. Due to overfishing and habitat alteration, the abundance of wild stocks has rapidly declined in recent years. Using wild adults, artificial spawning began in the 1950s in China, and since the early 1990s Amur sturgeon has become the most popular sturgeon for aquaculture. The species is adaptive to many conditions of artificial culture, including traditional Chinese fish culture ponds, lakes, reservoirs, and cages. It will grow well on many types of food, and 1-year-old fish reared on commercial diets weigh 900-1200 g. Based on the examination of females reared for broodstock, first full sexual maturity is expected at 5-6 years of age.

  20. Ecological requirements for pallid sturgeon reproduction and recruitment in the Missouri River—Annual report 2013

    USGS Publications Warehouse

    Delonay, Aaron J.; Jacobson, Robert B.; Chojnacki, Kimberly A.; Braaten, Patrick J.; Buhl, Kevin J.; Eder, Brandon L; Elliott, Caroline M.; Erwin, Susannah O.; Fuller, David B.; Haddix, Tyler M.; Ladd, Hallie L.A.; Mestl, Gerald E.; Papoulias, Diana M.; Rhoten, Jason C.; Wesolek, Christopher J.; Wildhaber, Mark L.

    2016-01-01

    The research tasks in the 2013 scope of work emphasized understanding reproductive migrations and spawning of adult pallid sturgeon, and hatch and drift of free embryos and larvae. These tasks were addressed in four study sections located in three hydrologically and geomorphologically distinct parts of the Missouri River Basin: the Upper Missouri River downstream from Fort Peck Dam, including downstream reaches of the Milk River, the Lower Yellowstone River, and the Lower Missouri River downstream from Gavins Point Dam. The research is designed to inform management decisions related to channel re-engineering, flow modification, and pallid sturgeon population augmentation on the Missouri River, and throughout the range of the species. Research and progress made through this project are reported to the U.S. Army Corps of Engineers annually. This annual report details the research effort and progress made by the Comprehensive Sturgeon Research Project during 2013.

  1. Life history and status of shortnose sturgeon (Acipenser brevirostrum) in the Potomac River

    USGS Publications Warehouse

    Kieffer, Micah

    2009-01-01

    We collected the first life history information on shortnose sturgeon (Acipenser brevirostrum) in any of the rivers to Chesapeake Bay, the geographic center of the species range. In the Potomac River, two telemetry-tagged adult females used 124 km of river: a saltwater/freshwater reach at river km (rkm) 63-141 was the foraging-wintering concentration area, and one female migrated to spawn at rkm 187 in Washington, DC. The spawning migration explained the life history context of an adult captured 122 years ago in Washington, DC, supporting the idea that a natal population once lived in the river. Repeated homing migrations to foraging and wintering areas suggested the adults were residents, not transient coastal migrants. All habitats that adults need to complete life history are present in the river. The Potomac River shortnose sturgeon offers a rare opportunity to learn about the natural rebuilding of a sturgeon population.

  2. Life history and status of shortnose sturgeon (Acipenser brevirostrum) in the potomac river

    USGS Publications Warehouse

    Kynard, B.; Breece, M.; Atcheson, M.; Kieffer, M.; Mangold, M.

    2009-01-01

    We collected the first life history information on shortnose sturgeon (Acipenser brevirostrum) in any of the rivers to Chesapeake Bay, the geographic center of the species range. In the Potomac River, two telemetry-tagged adult females used 124 km of river: A saltwater/freshwater reach at river km (rkm) 63-141 was the foraging-wintering concentration area, and one female migrated to spawn at rkm 187 in Washington, DC. The spawning migration explained the life history context of an adult captured 122 years ago in Washington, DC, supporting the idea that a natal population once lived in the river. Repeated homing migrations to foraging and wintering areas suggested the adults were residents, not transient coastal migrants. All habitats that adults need to complete life history are present in the river. The Potomac River shortnose sturgeon offers a rare opportunity to learn about the natural rebuilding of a sturgeon population. ?? 2009 Blackwell Verlag, Berlin.

  3. [Mitochondrial DNA sequence variation, demographic history, and population structure of Amur sturgeon Acipenser schrenckii Brandt, 1869].

    PubMed

    Shedko, S V; Miroshnichenko, I L; Nemkova, G A; Koshelev, V N; Shedko, M B

    2015-02-01

    The variability of the mtDNA control region (D-loop) was examined in Amur sturgeon endemic to the Amur River. This species is also classified as critically endangered by the IUCN Red List of Threatened species. Sequencing of 796- to 812-bp fragments of the D-loop in 112 sturgeon collected in the Lower Amur revealed 73 different genotypes. The sample was characterized by a high level of haplotypic (0.976) and nucleotide (0.0194) diversity. The identified haplotypes split into two well-defined monophyletic groups, BG (n = 39) and SM (n = 34), differing (HKY distance) on average by 3.41% of nucleotide positions upon an average level of intragroup differences of 0.54 and 1.23%, respectively. Moreover, the haplotypes of the SM groups differed by the presence of a 13-14 bp deletion. Most ofthe samples (66 out of 112) carried BG haplotypes. Overall, the pattern of pairwise nucleotide differences and the results of neutrality tests, as well as the results of tests for compliance with the model of sudden demographic expansion or with the model of exponential growth pointed to a past significant increase in the number of Amur sturgeon, which was most clearly manifested in the analysis of data on the BG haplogroup. The constructed Bayesian skyline plots showed that this growth began about 18 to 16 thousand years ago. At present, the effective size of the strongly reduced (due to overharvesting) population of Amur sturgeon may be equal to or even lower than it was before the beginning of this growth during the Last Glacial Maximum. The presence in the mitochondrial gene pool ofAmur sturgeon of two haplogroups, their unequal evolutionary dynamics, and, judging by scanty data, their unequal representation in the Russian and Chinese parts of the Amur River basin point to the possible existence of at least two distinct populations of Amur sturgeon in the past. PMID:25966586

  4. Reproductive traits of shovelnose sturgeon Scaphirhynchus platorynchus (Rafinesque, 1820) in the lower Platte River, Nebraska

    USGS Publications Warehouse

    Hamel, M. J.; Rugg, M.L.; Pegg, M.A.; Patino, Reynaldo; Hammen, J.J.

    2015-01-01

    We assessed reproductive status, fecundity, egg size, and spawning dynamics of shovelnose sturgeon Scaphirhynchus platorynchus in the lower Platte River. Shovelnose sturgeon were captured throughout each year during 2011 and 2012 using a multi-gear approach designed to collect a variety of fish of varying sizes and ages. Fish were collected monthly for a laboratory assessment of reproductive condition. Female shovelnose sturgeon reached fork length at 50% maturity (FL50) at 547 mm and at a minimum length of 449 mm. The average female spawning cycle was 3–5 years. Mean egg count for adult females was 16 098 ± 1103 (SE), and mean egg size was 2.401 ± 0.051 (SE) mm. Total fecundity was positively correlated with length (r2 = 0.728; P < 0.001), mass (r2 = 0.896; P < 0.001), and age (r2 = 0.396; P = 0.029). However, fish size and age did not correlate to egg size (P > 0.05). Male shovelnose sturgeon reached FL50 at 579 mm and at a minimum length of 453 mm. The average male spawning cycle was 1–2 years. Reproductively viable male and female sturgeon occurred during the spring (March–May) and autumn (September–October) in both years, indicating spring and potential autumn spawning events. Shovelnose sturgeon in the lower Platte River are maturing at a shorter length and younger age compared to populations elsewhere. Although it is unknown if the change is plastic or evolutionary, unfavorable environmental conditions or over-harvest may lead to hastened declines compared to other systems.

  5. Effects of Acclimation on Poststocking Dispersal and Physiological Condition of Age-1 Pallid Sturgeon

    SciTech Connect

    Oldenburg, Eric W.; Guy, Christopher S.; Cureton, Eli S.; Webb, Molly H.; Gardner, William M.

    2011-03-28

    A propagation program for pallid sturgeon Scaphirhynchus albus in the upper Missouri River was implemented by the U. S. Fish and Wildlife Service in 1997. Preliminary research indicated that many hatchery-reared pallid sturgeon were experiencing significant downstream poststocking dispersal, negatively affecting their recruitment. Therefore, the objective of this study was to evaluate the effects of acclimation to flow and site-specific physicochemical water conditions on poststocking dispersal and physiological condition of age-1 pallid sturgeon. Fish from three acclimation treatments were radio-tagged, released at two locations (Missouri River and Marias River), and monitored using passive telemetry stations. Marias treatment was acclimated to flow and site-specific physicochemical conditions, Bozeman treatment was acclimated to flow only, and traditional treatment had no acclimation (reared under traditional protocol). During both years fish released in the Missouri River dispersed less than fish released in the Marias River. In 2005, Marias treatment dispersed less and nearly twice as many fish remained in the Missouri River reach than traditional treatment. In 2006, pallid sturgeon dispersed similarly among treatments and fish remaining in the Missouri River reach were similar among all treatments. Differences in poststocking dispersal between years may be related to fin curl. Fin curl was present in all fish in 2005 and 27% of the fish in 2006. Pallid sturgeon from all treatments in both years had a greater affinity for the lower reaches of the Missouri River than the upper reaches. Thus, habitat at release site influenced poststocking dispersal more than acclimation treatment. No difference was observed in relative growth rate among treatments in 2006. However, acclimation to flow (i.e., exercise conditioning) may reduce liver fat content. Acclimation conditions used in this study may not benefit pallid sturgeon unless physiological maladies are present

  6. [Mitochondrial DNA sequence variation, demographic history, and population structure of Amur sturgeon Acipenser schrenckii Brandt, 1869].

    PubMed

    Shedko, S V; Miroshnichenko, I L; Nemkova, G A; Koshelev, V N; Shedko, M B

    2015-02-01

    The variability of the mtDNA control region (D-loop) was examined in Amur sturgeon endemic to the Amur River. This species is also classified as critically endangered by the IUCN Red List of Threatened species. Sequencing of 796- to 812-bp fragments of the D-loop in 112 sturgeon collected in the Lower Amur revealed 73 different genotypes. The sample was characterized by a high level of haplotypic (0.976) and nucleotide (0.0194) diversity. The identified haplotypes split into two well-defined monophyletic groups, BG (n = 39) and SM (n = 34), differing (HKY distance) on average by 3.41% of nucleotide positions upon an average level of intragroup differences of 0.54 and 1.23%, respectively. Moreover, the haplotypes of the SM groups differed by the presence of a 13-14 bp deletion. Most ofthe samples (66 out of 112) carried BG haplotypes. Overall, the pattern of pairwise nucleotide differences and the results of neutrality tests, as well as the results of tests for compliance with the model of sudden demographic expansion or with the model of exponential growth pointed to a past significant increase in the number of Amur sturgeon, which was most clearly manifested in the analysis of data on the BG haplogroup. The constructed Bayesian skyline plots showed that this growth began about 18 to 16 thousand years ago. At present, the effective size of the strongly reduced (due to overharvesting) population of Amur sturgeon may be equal to or even lower than it was before the beginning of this growth during the Last Glacial Maximum. The presence in the mitochondrial gene pool ofAmur sturgeon of two haplogroups, their unequal evolutionary dynamics, and, judging by scanty data, their unequal representation in the Russian and Chinese parts of the Amur River basin point to the possible existence of at least two distinct populations of Amur sturgeon in the past.

  7. White Oak Creek Watershed: Melton Valley Area Remedial Investigation Report, Oak Ridge National Laboratory, Oak Ridge, Tennessee: Volume 3 Appendix C

    SciTech Connect

    1996-11-01

    This report provides details on the baseline ecological risk assessment conducted in support of the Remedial Investigation (RI) Report for the Melton Valley areas of the White Oak Creek watershed (WOCW). The RI presents an analysis meant to enable the US Department of Energy (DOE) to pursue a series of remedial actions resulting in site cleanup and stabilization. The ecological risk assessment builds off of the WOCW screening ecological risk assessment. All information available for contaminated sites under the jurisdiction of the US Department of Energy`s Comprehensive Environmental Response, Compensation, and Liability Act Federal Facilities Agreement within the White Oak Creek (WOC) RI area has been used to identify areas of potential concern with respect to the presence of contamination posing a potential risk to ecological receptors within the Melton Valley area of the White Oak Creek watershed. The risk assessment report evaluates the potential risks to receptors within each subbasin of the watershed as well as at a watershed-wide scale. The WOC system has been exposed to contaminant releases from Oak Ridge National Laboratory and associated operations since 1943 and continues to receive contaminants from adjacent waste area groupings.

  8. Growth rates of young-of-year shovelnose sturgeon in the Upper Missouri River

    USGS Publications Warehouse

    Braaten, P.J.; Fuller, D.B.

    2007-01-01

    Information on growth during the larval and young-of-year life stages in natural river environments is generally lacking for most sturgeon species. In this study, methods for estimating ages and quantifying growth were developed for field-sampled larval and young-of-year shovelnose sturgeon Scaphirhynchus platorynchus in the upper Missouri River. First, growth was assessed by partitioning samples of young-of-year shovelnose sturgeon into cohorts, and regressing weekly increases in cohort mean length on sampling date. This method quantified relative growth because ages of the cohorts were unknown. Cohort increases in mean length among sampling dates were positively related (P 0.59 for all cohorts) to sampling date, and yielded growth rate estimates of 0.80-2.95 mm day-1 (2003) and 0.44-2.28 mm day-1 (2004). Highest growth rates occurred in the largest (and earliest spawned) cohorts. Second, a method was developed to estimate cohort hatch dates, thus age on date of sampling could be determined. This method included quantification of post-hatch length increases as a function of water temperature (growth capacity; mm per thermal unit, mm TU-1), and summation of mean daily water temperatures to achieve the required number of thermal units that corresponded to post-hatch lengths of shovelnose sturgeon on sampling dates. For six of seven cohorts of shovelnose sturgeon analyzed, linear growth models (r2 ??? 0.65, P < 0.0001) or Gompertz growth models (r2 ??? 0.83, P < 0.0001) quantified length-at-age from hatch through 55 days post-hatch (98-100 mm). Comparisons of length-at-age derived from the growth models indicated that length-at-age was greater for the earlier-hatched cohorts than later-hatched cohorts. Estimated hatch dates for different cohorts were corroborated based on the dates that newly-hatched larval shovelnose sturgeon were sampled in the drift. These results provide the first quantification of growth dynamics for field-sampled age-0 shovelnose sturgeon in a

  9. Growth rates of young-of-year shovelnose sturgeon in the Upper Missouri River

    USGS Publications Warehouse

    Braaten, P. J.; Fuller, D.B.

    2007-01-01

    Information on growth during the larval and young-of-year life stages in natural river environments is generally lacking for most sturgeon species. In this study, methods for estimating ages and quantifying growth were developed for field-sampled larval and young-of-year shovelnose sturgeon Scaphirhynchus platorynchus in the upper Missouri River. First, growth was assessed by partitioning samples of young-of-year shovelnose sturgeon into cohorts, and regressing weekly increases in cohort mean length on sampling date. This method quantified relative growth because ages of the cohorts were unknown. Cohort increases in mean length among sampling dates were positively related (P < 0.05, r2 > 0.59 for all cohorts) to sampling date, and yielded growth rate estimates of 0.80–2.95 mm day−1 (2003) and 0.44–2.28 mm day−1 (2004). Highest growth rates occurred in the largest (and earliest spawned) cohorts. Second, a method was developed to estimate cohort hatch dates, thus age on date of sampling could be determined. This method included quantification of post-hatch length increases as a function of water temperature (growth capacity; mm per thermal unit, mm TU−1), and summation of mean daily water temperatures to achieve the required number of thermal units that corresponded to post-hatch lengths of shovelnose sturgeon on sampling dates. For six of seven cohorts of shovelnose sturgeon analyzed, linear growth models (r2 ≥ 0.65, P < 0.0001) or Gompertz growth models (r2 ≥ 0.83, P < 0.0001) quantified length-at-age from hatch through 55 days post-hatch (98–100 mm). Comparisons of length-at-age derived from the growth models indicated that length-at-age was greater for the earlier-hatched cohorts than later-hatched cohorts. Estimated hatch dates for different cohorts were corroborated based on the dates that newly-hatched larval shovelnose sturgeon were sampled in the drift. These results provide the first quantification of growth dynamics

  10. Missouri River Scaphirhynchus albus (pallid sturgeon) effects analysis—Integrative report 2016

    USGS Publications Warehouse

    Jacobson, Robert B.; Annis, Mandy L.; Colvin, Michael E.; James, Daniel A.; Welker, Timothy L.; Parsley, Michael J.

    2016-07-15

    The Missouri River Pallid Sturgeon Effects Analysis was designed to carry out three components of an assessment of how Missouri River management has affected, and will affect, population dynamics of endangered Scaphirhynchus albus (pallid sturgeon): (1) collection of reliable scientific information, (2) critical assessment and synthesis of available data and analyses, and (3) analysis of the effects of actions on listed species and their habitats. This report is a synthesis of the three components emphasizing development of lines of evidence relating potential future management actions to pallid sturgeon population dynamics. We address 21 working management hypotheses that emerged from an expert opinion-based filtering process.The ability to quantify linkages from abiotic changes to pallid sturgeon population dynamics is compromised by fundamental information gaps. Although a substantial foundation of pallid sturgeon science has been developed during the past 20 years, our efforts attempt to push beyond that understanding to provide predictions of how future management actions may affect pallid sturgeon responses. For some of the 21 hypotheses, lines of evidence are limited to theoretical deduction, inference from sparse empirical datasets, or expert opinion. Useful simulation models have been developed to predict the effects of management actions on survival of drifting pallid sturgeon free embryos in the Yellowstone and Upper Missouri River complex (hereafter referred to as the “upper river”), and to assess the effects of flow and channel reconfigurations on habitat availability in the Lower Missouri River, tributaries, and Mississippi River downstream of Gavins Point Dam (hereafter referred to as the “lower river”). A population model also has been developed that can be used to assess sensitivity of the population to survival of specific life stages, assess some hypotheses related to stocking decisions, and explore a limited number of management

  11. Diet composition and feeding patterns of adult shovelnose sturgeon (Scaphirhynchus platorynchus) in the lower Platte River, Nebraska, USA

    USGS Publications Warehouse

    Rapp, T.; Shuman, D.A.; Graeb, B.D.S.; Chipps, Steven R.; Peters, E.J.

    2011-01-01

    Two-hundred and seven adult shovelnose sturgeon ranging from 450 to 718 mm in length were sampled from June to October 2001 and May to July 2002 to determine diet composition and feeding patterns in the lower Platte River. Shovelnose sturgeon fed primarily upon aquatic insect larvae and nymphs (>99% composition by number). Diptera of the family Chironomidae were the dominant prey items in both years and composed 98.1% of the shovelnose sturgeon diet in 2001 and 96.8% in 2002. Chironomidae were primarily represented by the four genera Paracladopelma, Chernovskiia, Saetheria and Robackia accounting for 90.2% of the ingested prey items in 2001 and 83.6% in 2002. In addition, shovelnose sturgeon showed in both years a generalized feeding pattern towards Ephemeroptera of the families Isonychiidae and Caenidae, as well as Trichoptera of the family Hydropsychidae. Other aquatic insects, terrestrial invertebrates and fishes were found infrequently and in low numbers in shovelnose sturgeon diets. The four most abundant Chironomidae genera are often found on sand and the high abundance of these taxa in the diet suggests that shovelnose sturgeon feed primarily near or on this substrate type. This highlights the importance of habitats that provide sand substrate for shovelnose sturgeon foraging in the lower Platte River.

  12. Destruction of Listeria monocytogenes in sturgeon (Acipenser transmontanus) caviar by a combination of nisin with chemical antimicrobials or moderate heat.

    PubMed

    Al-Holy, M; Lin, M; Rasco, B

    2005-03-01

    The objective of this study was to investigate the effect of nisin in combination with heat or antimicrobial chemical treatments (such as lactic acid, chlorous acid, and sodium hypochlorite) on the inhibition of Listeria monocytogenes and total mesophiles in sturgeon (Acipenser transmontanus) caviar. The effects of nisin (250, 500, 750, and 1,000 IU/ml), lactic acid (1, 2, and 3%), chlorous acid (134 and 268 ppm), sodium hypochlorite (150 and 300 ppm), and heat at 60 degrees C for 3 min were evaluated for a five-strain mixture of L. monocytogenes and total mesophiles in sturgeon caviar containing 3.5% salt. Selected combinations of these antimicrobial treatments were also tested. Injured and viable L. monocytogenes cells were recovered using an overlay method. Treating caviar with > or =500 IU/ml nisin initially reduced L. monocytogenes by 2 to 2.5 log units. Chlorous acid (268 ppm) reduced L. monocytogenes from 7.7 log units to undetectable (<0.48 log units) after 4 days of storage at 4 degrees C. However, there were no synergistic effects observed for combinations of nisin (500 or 750 IU/ml) plus either lactic acid or chlorous acid. Lactic acid caused a slight reduction (approximately 1 log unit) in the microbial load during a 6-day period at 4 degrees C. Sodium hypochlorite was ineffective at the levels tested. Mild heating (60 degrees C for 3 min) with nisin synergistically reduced viable counts of L. monocytogenes and total mesophiles. No L. monocytogenes cells (<0.48 log units) were recovered from caviar treated with heat and nisin (750 IU/ml) after a storage period of 28 days at 4 degrees C. PMID:15771175

  13. High-throughput sequencing of microRNA transcriptome and expression assay in the sturgeon, Acipenser schrenckii.

    PubMed

    Yuan, Lihong; Zhang, Xiujuan; Li, Linmiao; Jiang, Haiying; Chen, Jinping

    2014-01-01

    Sturgeons are considered as living fossils and have very high evolutionary, economical and conservation values. The multiploidy of sturgeon that has been caused by chromosome duplication may lead to the emergence of new microRNAs (miRNAs) involved in the ploidy and physiological processes. In the present study, we performed the first sturgeon miRNAs analysis by RNA-seq high-throughput sequencing combined with expression assay of microarray and real-time PCR, and aimed to discover the sturgeon-specific miRNAs, confirm the expressed pattern of miRNAs and illustrate the potential role of miRNAs-targets on sturgeon biological processes. A total of 103 miRNAs were identified, including 58 miRNAs with strongly detected signals (signal >500 and P≤0.01), which were detected by microarray. Real-time PCR assay supported the expression pattern obtained by microarray. Moreover, co-expression of 21 miRNAs in all five tissues and tissue-specific expression of 16 miRNAs implied the crucial and particular function of them in sturgeon physiological processes. Target gene prediction, especially the enriched functional gene groups (369 GO terms) and pathways (37 KEGG) regulated by 58 miRNAs (P<0.05), illustrated the interaction of miRNAs and putative mRNAs, and also the potential mechanism involved in these biological processes. Our new findings of sturgeon miRNAs expand the public database of transcriptome information for this species, contribute to our understanding of sturgeon biology, and also provide invaluable data that may be applied in sturgeon breeding.

  14. Sailing to White Boat

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This is a composite red-green-blue image of the rock called White Boat. It is the first rock target that Spirit drove to after finishing a series of investigations on the rock Adirondack. White Boat stood out to scientists due to its light color and more tabular shape compared to the dark, rounded rocks that surround it.

  15. Acute toxicity of TFM and a TFM/niclosamide mixture to selected species of fish, including lake sturgeon (Acipenser fulvescens) and mudpuppies (Necturus maculosus), in laboratory and field exposures

    USGS Publications Warehouse

    Boogaard, M.A.; Bills, T.D.; Johnson, D.A.

    2003-01-01

    The toxicity of the lampricides 3-trifluoromethyl-4-nitrophenol (TFM) and 2???,5-dichloro-4???-nitrosalicylanilide (niclosamide) to non-target fishes has been a major point of concern since their use to control larval sea lamprey (Petromyzon marinus) populations began in the early 1960s. The toxicity of TFM to several non-target fish species has been demonstrated in previous studies. However, little information is available on the toxicity of the TFM/1 % niclosamide mixture. One species of particular concern is the lake sturgeon (Acipenser fulvescens). Juvenile lake sturgeon of several size ranges were exposed to determine potential effects of the lampricides to individuals present in treatment streams. Sac fry were most resistant to the lampricides followed by fingerlings in the 200 to 225 mm size range. Swim-up fry and fingerlings less than 100 mm were the most sensitive. Concentrations that produced 50% mortality (LC50s) in juvenile lake sturgeon of these smaller size ranges were at or near the minimum lethal concentrations (MLCs) required for effective control of larval sea lampreys. The mudpuppy (Necturus maculosus), an amphibian native to several tributaries of the Great Lakes, have also become a species of interest in recent years. Laboratory tests conducted with TFM and a TFM/1 % niclosamide mixture on adult mudpuppies indicate that although the amphibian is sensitive to the lampricides, an adequate margin of safety exists for adult mudpuppies to survive when exposed during stream treatments. Fifteen other fish species native to streams treated with lampricides were investigated in the laboratory to determine their sensitivity to the lampricides. Centrarchids, bluegill (Lepomis macrochirus) and green sunfish (Lepomis cyanellus) were the least sensitive to TFM, while ictalurids, black bullhead (Ictalurus melas), channel catfish (Ictalurus punctatus), and tadpole madtom (Notorus gyrinus) were the most sensitive. On-site bioassays conducted before lampricide

  16. Acute toxicity of TFM and a TFM/niclosamide mixture to selected species of fish, including lake sturgeon (Acipenser fulvescens) and mudpuppies (Necturus maculosus), in laboratory and field exposures

    USGS Publications Warehouse

    Boogaard, M.A.; Bills, T.D.; Johnson, D.A.

    2003-01-01

    The toxicity of the lampricides 3-trifluoromethyl-4-nitrophenol (TFM) and 2',5-dichloro-4'-nitrosalicylanilide (niclosamide) to non-target fishes has been a major point of concern since their use to control larval sea lamprey (Petromyzon marinus) populations began in the early 1960s. The toxicity of TFM to several non-target fish species has been demonstrated in previous studies. However, little information is available on the toxicity of the TFM/1% niclosamide mixture. One species of particular concern is the lake sturgeon (Acipenser fulvescens). Juvenile lake sturgeon of several size ranges were exposed to determine potential effects of the lampricides to individuals present in treatment streams. Sac fry were most resistant to the lampricides followed by fingerlings in the 200 to 225 mm size range. Swim-up fry and fingerlings less than 100 mm were the most sensitive. Concentrations that produced 50% mortality (LC50s) in juvenile lake sturgeon of these smaller size ranges were at or near the minimum lethal concentrations (MLCs) required for effective control of larval sea lampreys. The mudpuppy (Necturus maculosus), an amphibian native to several tributaries of the Great Lakes, have also become a species of interest in recent years. Laboratory tests conducted with TFM and a TFM/1% niclosamide mixture on adult mudpuppies indicate that although the amphibian is sensitive to the lampricides, an adequate margin of safety exists for adult mudpuppies to survive when exposed during stream treatments. Fifteen other fish species native to streams treated with lampricides were investigated in the laboratory to determine their sensitivity to the lampricides. Centrarchids, bluegill (Lepomis macrochirus) and green sunfish (Lepomis cyanellus) were the least sensitive to TFM, while ictalurids, black bullhead (Ictalurus melas), channel catfish (Ictalurus punctatus), and tadpole madtom (Notorus gyrinus) were the most sensitive. On-site bioassays conducted before lampricide

  17. Current Occurrence of the Atlantic Sturgeon Acipenser oxyrinchus in Northern Spain: A New Prospect for Sturgeon Conservation in Western Europe.

    PubMed

    Elvira, Benigno; Leal, Sheila; Doadrio, Ignacio; Almodóvar, Ana

    2015-01-01

    Acipenser oxyrinchus is considered extirpated in Europe, but numerous breeding populations still exist on the Atlantic coast of North America. An adult female A. oxyrinchus, 2500 mm total length and 120 kg wet weight, was accidentally fished on 24 November 2010 near the coast of Gijón, Asturias, Spain. The fish was identified by its morphological pattern as well as by mitochondrial and nuclear DNA analyses. Because the sturgeon was found far away from any known breeding area, it was considered a stray or vagrant specimen. It certainly has a natural origin, but its eventual birthplace could not be determined. Because its current occurrence was unknown in southwestern Europe until now, the species is not cataloged or protected in this area. Therefore, the residual European stocks of A. oxyrinchus ought to be listed as Critically Endangered (CR) according to the IUCN categories. Likewise, it is imperative for southwestern European countries with an historic or recent occurrence of A. oxyrinchus to protect the species through domestic and international legislation. The present sympatric occurrence of A. sturio and A. oxyrinchus raises new challenges about key questions, such as the species selection for restoration program in European countries. Accurate monitoring is mandatory to obtain appropriate information for an assessment of the current occurrence of A. oxyrinchus in southwestern Europe.

  18. Current Occurrence of the Atlantic Sturgeon Acipenser oxyrinchus in Northern Spain: A New Prospect for Sturgeon Conservation in Western Europe

    PubMed Central

    Elvira, Benigno

    2015-01-01

    Acipenser oxyrinchus is considered extirpated in Europe, but numerous breeding populations still exist on the Atlantic coast of North America. An adult female A. oxyrinchus, 2500 mm total length and 120 kg wet weight, was accidentally fished on 24 November 2010 near the coast of Gijón, Asturias, Spain. The fish was identified by its morphological pattern as well as by mitochondrial and nuclear DNA analyses. Because the sturgeon was found far away from any known breeding area, it was considered a stray or vagrant specimen. It certainly has a natural origin, but its eventual birthplace could not be determined. Because its current occurrence was unknown in southwestern Europe until now, the species is not cataloged or protected in this area. Therefore, the residual European stocks of A. oxyrinchus ought to be listed as Critically Endangered (CR) according to the IUCN categories. Likewise, it is imperative for southwestern European countries with an historic or recent occurrence of A. oxyrinchus to protect the species through domestic and international legislation. The present sympatric occurrence of A. sturio and A. oxyrinchus raises new challenges about key questions, such as the species selection for restoration program in European countries. Accurate monitoring is mandatory to obtain appropriate information for an assessment of the current occurrence of A. oxyrinchus in southwestern Europe. PMID:26717564

  19. A Prospective Pilot Investigation of Brain Volume, White Matter Hyperintensities, and Hemorrhagic Lesions after Mild Traumatic Brain Injury

    PubMed Central

    Jarrett, Michael; Tam, Roger; Hernández-Torres, Enedino; Martin, Nancy; Perera, Warren; Zhao, Yinshan; Shahinfard, Elham; Dadachanji, Shiroy; Taunton, Jack; Li, David K. B.; Rauscher, Alexander

    2016-01-01

    Traumatic brain injury (TBI) is among the most common neurological disorders. Hemorrhagic lesions and white matter hyperintensities (WMH) are radiological features associated with moderate and severe TBI. Brain volume reductions have also been observed during the months following injury. In concussion, no signs of injury are observed on conventional magnetic resonance imaging (MRI), which may be a true feature of concussion or merely due to the limited sensitivity of imaging techniques used so far. Moreover, it is not known whether volume reductions are due to the resolution of trauma-related edema or a true volume loss. Forty-five collegiate-level ice hockey players (20 females) and 15 controls (9 females), 40 players underwent 3-T MRI for hemorrhages [multi-echo susceptibility-weighted imaging (SWI)], WMH (three-dimensional fluid-attenuated inversion recovery), and brain volume at the beginning and the end of the hockey season. Concussed athletes underwent additional imaging and neuropsychological testing at 3 days, 2 weeks, and 2 months after injury. At the end of the hockey season, brain volume was reduced compared to controls by 0.32% (p < 0.034) in the whole cohort and by 0.26% (p < 0.09) in the concussed athletes. Two weeks and 2 months after concussion, brain volume was reduced by −0.08% (p = 0.027) and −0.23% (p = 0.035), respectively. In athletes, the WMH were significantly closer to the interface between gray matter and white matter compared to controls. No significant changes in the number of WMH over the duration of the study were found in athletes. No microhemorrhages were detected as a result of concussion or playing a season of ice hockey. We conclude that mild TBI does not lead to transient increases in brain volume and no new microbleeds or WMH are detectable after concussion. Brain volume reductions appear by 2 weeks after concussion and persist until at least 2 months after concussion. Brain volume is reduced

  20. A Prospective Pilot Investigation of Brain Volume, White Matter Hyperintensities, and Hemorrhagic Lesions after Mild Traumatic Brain Injury.

    PubMed

    Jarrett, Michael; Tam, Roger; Hernández-Torres, Enedino; Martin, Nancy; Perera, Warren; Zhao, Yinshan; Shahinfard, Elham; Dadachanji, Shiroy; Taunton, Jack; Li, David K B; Rauscher, Alexander

    2016-01-01

    Traumatic brain injury (TBI) is among the most common neurological disorders. Hemorrhagic lesions and white matter hyperintensities (WMH) are radiological features associated with moderate and severe TBI. Brain volume reductions have also been observed during the months following injury. In concussion, no signs of injury are observed on conventional magnetic resonance imaging (MRI), which may be a true feature of concussion or merely due to the limited sensitivity of imaging techniques used so far. Moreover, it is not known whether volume reductions are due to the resolution of trauma-related edema or a true volume loss. Forty-five collegiate-level ice hockey players (20 females) and 15 controls (9 females), 40 players underwent 3-T MRI for hemorrhages [multi-echo susceptibility-weighted imaging (SWI)], WMH (three-dimensional fluid-attenuated inversion recovery), and brain volume at the beginning and the end of the hockey season. Concussed athletes underwent additional imaging and neuropsychological testing at 3 days, 2 weeks, and 2 months after injury. At the end of the hockey season, brain volume was reduced compared to controls by 0.32% (p < 0.034) in the whole cohort and by 0.26% (p < 0.09) in the concussed athletes. Two weeks and 2 months after concussion, brain volume was reduced by -0.08% (p = 0.027) and -0.23% (p = 0.035), respectively. In athletes, the WMH were significantly closer to the interface between gray matter and white matter compared to controls. No significant changes in the number of WMH over the duration of the study were found in athletes. No microhemorrhages were detected as a result of concussion or playing a season of ice hockey. We conclude that mild TBI does not lead to transient increases in brain volume and no new microbleeds or WMH are detectable after concussion. Brain volume reductions appear by 2 weeks after concussion and persist until at least 2 months after concussion. Brain volume is reduced between

  1. The Social Milieu of the Church and Religious Coping Responses: A Longitudinal Investigation of Older Whites and Older Blacks

    PubMed Central

    Krause, Neal

    2010-01-01

    The purpose of this study is to see if the social environment of the church influences the use of religious coping responses over time. The following theoretical relationships were embedded in the conceptual model that was developed to evaluate this issue: (1) people who go to church more often are more likely to feel their congregation is highly cohesive (e.g., share the same values and beliefs); (2) individuals who worship in highly cohesive congregations are more likely to receive spiritual support (i.e., encouragement to adopt religious teachings and principles) from their fellow church members; (3) people who receive more spiritual support will be more likely to adopt religious coping responses. In the process of evaluating this model, tests were performed to examine the influence of racial culture. Data from a nationwide longitudinal survey of older adults provide support for each link in the conceptual model. Pervasive racial cultural differences were also found: Older blacks were more likely to be deeply involved in each facet of religion than older whites. PMID:20556239

  2. An Investigation into Occasional White Spot Syndrome Virus Outbreak in Traditional Paddy Cum Prawn Fields in India

    PubMed Central

    Selvam, Deborah Gnana; Mujeeb Rahiman, K. M.; Mohamed Hatha, A. A.

    2012-01-01

    A yearlong (September 2009–August 2010) study was undertaken to find out possible reasons for occasional occurrence of White Spot Syndrome Virus (WSSV) outbreak in the traditional prawn farms adjoining Cochin backwaters. Physicochemical and bacteriological parameters of water and sediment from feeder canal and four shrimp farms were monitored on a fortnightly basis. The physicochemical parameters showed variation during the two production cycles and between the farms studied. Dissolved oxygen (DO) content of water from feeder canal showed low oxygen levels (as low as 0.8 mg/L) throughout the study period. There was no disease outbreak in the perennial ponds. Poor water exchange coupled with nutrient loading from adjacent houses resulted in phytoplankton bloom in shallow seasonal ponds which led to hypoxic conditions in early morning and supersaturation of DO in the afternoon besides considerably high alkaline pH. Ammonia levels were found to be very high in these ponds. WSSV outbreak was encountered twice during the study leading to mass mortalities in the seasonal ponds. The hypoxia and high ammonia content in water and abrupt fluctuations in temperature, salinity and pH might lead to considerable stress in the shrimps triggering WSSV infection in these traditional ponds. PMID:22593673

  3. A Critique of Carver and White's (1994) Behavioral Inhibition Scale (BIS) for Investigating Lykken's (1995) Theory of Primary Psychopathy.

    PubMed

    Poythress, Norman G; Edens, John F; Landfield, Kristin; Lilienfeld, Scott O; Skeem, Jennifer L; Douglas, Kevin S

    2008-09-01

    In a 1995 monograph, Lykken asserted that an innate fearless temperament underpins the development of primary psychopathy as described by Cleckley (1941). To embed this insight in a larger theory of behavior, Lykken embraced constructs from Gray's (1982) reinforcement sensitivity theory (RST). Specifically, he hypothesized that in primary psychopaths the behavioral inhibition system (BIS) lacks normal sensitivity to cues of conditioned punishment or non-reward. Subsequent researchers have embraced Carver and White's (1994) BIS scale as the instrument of choice for testing Lykken's theory of primary psychopathy, a practice that this review calls into question. We note (a) a dearth of research using the BIS scales in offender samples, where more psychopathic individuals are likely to be found and (b) limited BIS scale coverage of the functions attributed to the behavioral inhibition system in RST. In addition, (c) we review literature suggesting that rather than assessing the fear sensitivity function critical to Lykken's theory, the BIS scale instead functions primarily as an index of negative emotionality. We recommend a moratorium on the use of the BIS scale to test Lykken's theory of primary psychopathy.

  4. Lake sturgeon spawning on artificial habitat in the St Lawrence River

    USGS Publications Warehouse

    Johnson, J.H.; LaPan, S.R.; Klindt, R.M.; Schiavone, A.

    2006-01-01

    In 1996, lake sturgeon (Acipenser fulvescens) spawning was documented for the third consecutive year on an artificially placed gravel bed in the St Lawrence River. Two distinct spawning periods were observed in 1996. Spawning initially commenced on 17 June, when water temperature reached 15°C. A second spawning event was documented from 28 June to 1 July (16°C). Sturgeon egg densities were monitored in three transects on egg trays, on the gravel surface, and within interstitial spaces in the gravel. Counts of developing eggs in the gravel bed during both spawning periods were used to estimate a total of 275 000 eggs on the study area (0.075 ha). Average egg density was highest in the transect with the highest water velocities. Lake sturgeon fry were first observed in the gravel on 24 June (15.5°C), and first emergence from the gravel was documented on 28 June. Hatching following the second spawning event commenced on 3 July. Based on assessment of average embryo viability (61.6%) and egg-to-emergent fry survival (17.6%) an estimate of about 171 000 sturgeon eggs hatched, producing over 49 000 emergent fry. Current velocity, substrate particle size, depth of substrate, and maintenance of sediment-free interstitial spaces are important considerations in planning future spawning habitat enhancement projects.

  5. 75 FR 53598 - Endangered and Threatened Wildlife and Plants; Threatened Status for Shovelnose Sturgeon Under...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-01

    ...) (16 U.S.C. 1531 et seq.) (55 FR 36641, September 6, 1990). The pallid sturgeon has a flattened, shovel... species can be long-lived (40 plus years), with females reaching sexual maturity later than males... population size, limited natural reproduction, hybridization, pollution and contamination, entrainment,...

  6. Movement and habitat use of green sturgeon Acipenser medirostris in the Rogue River, Oregon, USA

    USGS Publications Warehouse

    Erickson, D.L.; North, J.A.; Hightower, J.E.; Weber, J.; Lauck, L.

    2002-01-01

    Green sturgeon (Acipenser medirostris) movement patterns and habitat use within the Rogue River, Oregon were evaluated using radio telemetry. Nineteen specimens ranging from 154 to 225 cm total length were caught by gill netting and tagged with radio transmitters during May-July 2000. One tagged green sturgeon was verified as a female near spawning condition. Individual green sturgeons spent more than 6 months in fresh water and traveled as far as river kilometer (rkm) 39.5. Green sturgeon preferred specific holding sites within the Rogue River during summer and autumn months. These sites were typically deep (> 5 m) low-gradient reaches or off-channel coves. Home ranges within holding sites were restricted. All tagged individuals emigrated from the system to the sea during the autumn and winter, when water temperatures dropped below 10??C and flows increased. This species is extremely vulnerable to habitat alterations and overfishing because it spawns in only a few North American rivers and individuals reside within extremely small areas for extended periods of time.

  7. ACUTE SENSITIVITY OF JUVENILE SHORTNOSE STURGEON TO LOW DISSOLVED OXYGEN CONCENTRATIONS

    EPA Science Inventory

    Campbell, Jed G. and Larry R. Goodman. 2004. Acute Sensitivity of Juvenile Shortnose Sturgeon to Low Dissolved Oxygen Concentrations. EPA/600/J-04/175. Trans. Am. Fish. Soc. 133(3):772-776. (ERL,GB 1155).

    There is considerable concern that factors such as eutrophication, ...

  8. Discrete choice modeling of shovelnose sturgeon habitat selection in the Lower Missouri River

    USGS Publications Warehouse

    Bonnot, T.W.; Wildhaber, M.L.; Millspaugh, J.J.; DeLonay, A.J.; Jacobson, R.B.; Bryan, J.L.

    2011-01-01

    Substantive changes to physical habitat in the Lower Missouri River, resulting from intensive management, have been implicated in the decline of pallid (Scaphirhynchus albus) and shovelnose (S. platorynchus) sturgeon. To aid in habitat rehabilitation efforts, we evaluated habitat selection of gravid, female shovelnose sturgeon during the spawning season in two sections (lower and upper) of the Lower Missouri River in 2005 and in the upper section in 2007. We fit discrete choice models within an information theoretic framework to identify selection of means and variability in three components of physical habitat. Characterizing habitat within divisions around fish better explained selection than habitat values at the fish locations. In general, female shovelnose sturgeon were negatively associated with mean velocity between them and the bank and positively associated with variability in surrounding depths. For example, in the upper section in 2005, a 0.5ms-1 decrease in velocity within 10m in the bank direction increased the relative probability of selection 70%. In the upper section fish also selected sites with surrounding structure in depth (e.g., change in relief). Differences in models between sections and years, which are reinforced by validation rates, suggest that changes in habitat due to geomorphology, hydrology, and their interactions over time need to be addressed when evaluating habitat selection. Because of the importance of variability in surrounding depths, these results support an emphasis on restoring channel complexity as an objective of habitat restoration for shovelnose sturgeon in the Lower Missouri River. ?? 2011 Blackwell Verlag, Berlin.

  9. Discrete choice modeling of shovelnose sturgeon habitat selection in the Lower Missouri River

    USGS Publications Warehouse

    Bonnot, T.W.; Wildhaber, M.L.; Millspaugh, J.J.; DeLonay, A.J.; Jacobson, R.B.; Bryan, J.L.

    2011-01-01

    Substantive changes to physical habitat in the Lower Missouri River, resulting from intensive management, have been implicated in the decline of pallid (Scaphirhynchus albus) and shovelnose (S. platorynchus) sturgeon. To aid in habitat rehabilitation efforts, we evaluated habitat selection of gravid, female shovelnose sturgeon during the spawning season in two sections (lower and upper) of the Lower Missouri River in 2005 and in the upper section in 2007. We fit discrete choice models within an information theoretic framework to identify selection of means and variability in three components of physical habitat. Characterizing habitat within divisions around fish better explained selection than habitat values at the fish locations. In general, female shovelnose sturgeon were negatively associated with mean velocity between them and the bank and positively associated with variability in surrounding depths. For example, in the upper section in 2005, a 0.5 m s-1 decrease in velocity within 10 m in the bank direction increased the relative probability of selection 70%. In the upper section fish also selected sites with surrounding structure in depth (e.g., change in relief). Differences in models between sections and years, which are reinforced by validation rates, suggest that changes in habitat due to geomorphology, hydrology, and their interactions over time need to be addressed when evaluating habitat selection. Because of the importance of variability in surrounding depths, these results support an emphasis on restoring channel complexity as an objective of habitat restoration for shovelnose sturgeon in the Lower Missouri River.

  10. Fish and chips? Implanted transmitters help map the endangered pallid sturgeon

    USGS Publications Warehouse

    Chojnacki, Kimberly; DeLonay, Aaron

    2011-01-01

    With a flattened snout, long slender tail and rows of bony plates lining its body, the pallid sturgeon (Scaphirhynchus albus) has a unique, almost pre-historic, appearance. This endangered fish is native to the muddy, free-flowing waters of the Missouri River.

  11. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (South Atlantic) - Atlantic sturgeon

    SciTech Connect

    Van Den Avyle, M.J.

    1984-07-01

    The Atlantic sturgeon, Acipenser oxyrhynchus oxyrhynchus, is an anadromous species that occupies rivers, estuaries, and nearshore waters along the entire Atlantic coast of the United States. The species once supported significant commercial fisheries throughout its range, but stocks have declined because of overfishing, deterioration of water quality, and damming of rivers. Atlantic sturgeon spawn in rivers and the young remain in freshwater for several years prior to emigration to the ocean. Little is known about spawning areas and associated environmental factors. Females typically do not mature until age X and the age at first spawning ranges from 5 to 13 years for males and 7 to 19 years for females. Longevity may frequently exceed 25 years. Immature and adult sturgeons are bottom feeders and consume a variety of mollusks, crustaceans, worms, and other small bottom-dwelling invertebrates and fishes. Little is know about competitors, predators, or effects of environmental factors on recruitment. The long period required to reach maturity, possibly irregular spawning thereafter, and prolonged reliance on river systems make juvenile and adult Atlantic sturgeon highly susceptible to habitat alterations, pollution, and over exploitation. 49 references, 2 figures, 4 tables.

  12. EFFECT OF CRYOPRESERVATION AND THEOPHYLLINE ON MOTILITY CHARACTERISTICS OF LAKE STURGEON (ACIPENSER FULVESCENS) SPERMATOZOA

    EPA Science Inventory

    Computer-assisted motility analysis (CASA) was used to evaluate the effect of cryopreservation and theophylline treatment on sperm motility of lake sturgeon (Acipenser fulvescens).Motility was recorded at 0 and 5 min postactivation.The effect of cryopreservation on sperm acrosin-...

  13. 50 CFR 23.71 - How can I trade internationally in sturgeon caviar?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false How can I trade internationally in sturgeon caviar? 23.71 Section 23.71 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE..., EXPORTATION, AND IMPORTATION OF WILDLIFE AND PLANTS (CONTINUED) CONVENTION ON INTERNATIONAL TRADE...

  14. 50 CFR 23.71 - How can I trade internationally in sturgeon caviar?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false How can I trade internationally in sturgeon caviar? 23.71 Section 23.71 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE..., EXPORTATION, AND IMPORTATION OF WILDLIFE AND PLANTS (CONTINUED) CONVENTION ON INTERNATIONAL TRADE...

  15. 50 CFR 23.71 - How can I trade internationally in sturgeon caviar?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false How can I trade internationally in sturgeon caviar? 23.71 Section 23.71 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE..., EXPORTATION, AND IMPORTATION OF WILDLIFE AND PLANTS (CONTINUED) CONVENTION ON INTERNATIONAL TRADE...

  16. 50 CFR 23.71 - How can I trade internationally in sturgeon caviar?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false How can I trade internationally in sturgeon caviar? 23.71 Section 23.71 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE..., EXPORTATION, AND IMPORTATION OF WILDLIFE AND PLANTS (CONTINUED) CONVENTION ON INTERNATIONAL TRADE...

  17. 50 CFR 23.71 - How can I trade internationally in sturgeon caviar?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false How can I trade internationally in sturgeon caviar? 23.71 Section 23.71 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE..., EXPORTATION, AND IMPORTATION OF WILDLIFE AND PLANTS (CONTINUED) CONVENTION ON INTERNATIONAL TRADE...

  18. Diagnosis of an unidentified sturgeon species using the complete mitochondrial DNA.

    PubMed

    Yu, Jeong-Nam; Kwak, Myounghai; Kweon, Seon-Man; Kwon, O-Nam

    2015-01-01

    A sturgeon of unknown species of 11 kg body weight was caught in Gosung-gun, Gangwon Province, Korea (38°17'10.67″N, 128°33'20.28″E). The morphological characteristics were similar to species of the genus Acipenser such as Acipenser medirostris, A. schrenckii and A. baerii, but it was not an obvious match. To identify the species using genetic tools, we analysed the complete mitogenome of this unidentified sturgeon, and found it to comprise 16,526 bp. The genome encoded 2 rRNAs, 22 tRNAs, 13 protein-coding genes and 1 control region. The nucleotide divergence between the complete mitogenome of the unidentified sturgeon and those of four Acipenser spp. (A. transmontanus, A. dabryanus, A. schrenckii and A. baerii) was 0.736%, 3.875%, 0.085% and 5.580%, respectively. This study suggests that the unidentified sturgeon is able to predict the least maternal lines with A. schrenckii.

  19. A PROTOCOL FOR THE SHORT-TERM STORAGE OF ATLANTIC STURGEON SEMEN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Short-term, liquid-phase storage trials were conducted in 2009 on Atlantic sturgeon semen obtained from captive males, held at the U.S. Fish and Wildlife Service, Northeast Fish Technology Center and wild males, collected ripe on the spawning grounds from the Hudson River. Semen samples collected, c...

  20. OBJECTIVE ANALYSIS OF SPERM MOTILITY IN THE LAKE STURGEON, ACIPENSER FULVESCENS: ACTIVATION AND INHIBITION CONDITIONS

    EPA Science Inventory

    An objective analysis of the duration of motility of sperm from the lake sturgeon, Acipenser fulvescens, has been performed using computer-assisted sperm motion analysis at 200 frames/s. Motility was measured in both 1993 and 1994. The percentage of activated motile sperm and the...

  1. Differential expression of fertility genes boule and dazl in Chinese sturgeon (Acipenser sinensis), a basal fish.

    PubMed

    Ye, Huan; Li, Chuang-Ju; Yue, Hua-Mei; Yang, Xiao-Ge; Wei, Qi-Wei

    2015-05-01

    The gene family DAZ (deleted in Azoospermia), including boule, dazl and DAZ, performs highly conserved functions in germ cell development and fertility across animal phyla. Differential expression patterns have been demonstrated for the family members in invertebrates and vertebrates including fish. Here, we report the identification of boule and dazl and their expression at both RNA and protein levels in developing and mature gonads of Chinese sturgeon (Acipenser sinensis). Firstly, the isolation of the boule and dazl genes in Chinese sturgeon and the observation of the two genes in coelacanth suggest that dazl originated after the divergence of bony fish from cartilaginous fish but before the emergence of the Actinistia. Quantitative real-time PCR and western blot analyses reveal that boule and dazl RNA and proteins are restricted to the testis and ovary. In situ hybridization and fluorescent immunohistochemistry show that the bisexual mitotic and meiotic germ cell expression of dazl RNA and protein is conserved in vertebrates, while Chinese sturgeon boule RNA and protein exhibit mitotic and meiotic expression in the testis, and also likely display mitotic and meiotic expression in female. Moreover, we directly demonstrate for the first time that sturgeon Balbiani body/mitochondrial cloud disperses in the cytoplasm of early developing oocytes and co-localizes with Dazl to some extent. Finally, urbilaterian boule may also have an ancestral function in oogenesis. Taken together, these results provide useful information on the evolution of DAZ family genes, expression patterns and functions in animal reproduction.

  2. Shortnose sturgeon use small coastal rivers: The importance of habitat connectivity

    USGS Publications Warehouse

    Zydlewski, G.B.; Kinnison, M.T.; Dionne, P.E.; Zydlewski, J.; Wippelhauser, G.S.

    2011-01-01

    Contrary to conventional wisdom for shortnose sturgeon (Acipenser brevirostrum), we document shortnose sturgeon use of habitats beyond large rivers. Telemetry data from 2008 to 2010 in the Gulf of Maine demonstrates that adult shortnose sturgeon (up to 70%) frequently move between Maine's two largest rivers, the Kennebec and Penobscot Rivers. Even more interesting, small rivers located between these watersheds were used by 52% of the coastal migrants. Small river use was not trivial, 80% of observed movements extended more than 10km upstream. However, visits were short in duration. This pattern indicates one of several possibilities: directed use of resources, searching behaviors related to reproduction (i.e. straying) or undirected wandering. Data suggest a relationship between residence time in small rivers and distance to the lowermost barrier. Restoring connectivity to upstream habitats in these rivers could allow opportunities for metapopulation expansion. Regional management of shortnose sturgeon in the Gulf of Maine should incorporate a habitat framework that considers small coastal rivers. ?? 2011 Blackwell Verlag, Berlin.

  3. Comparing Electronic News Media Reports of Potential Bioterrorism-Related Incidents Involving Unknown White Powder to Reports Received by the United States Centers for Disease Control and Prevention and the Federal Bureau of Investigation: USA, 2009–2011

    PubMed Central

    Fajardo, Geroncio C.; Posid, Joseph; Papagiotas, Stephen; Lowe, Luis

    2015-01-01

    There have been periodic electronic news media reports of potential bioterrorism-related incidents involving unknown substances (often referred to as “white powder”) since the 2001 intentional dissemination of Bacillus anthracis through the US Postal System. This study reviewed the number of unknown “white powder” incidents reported online by the electronic news media and compared them with unknown “white powder” incidents reported to the US Centers for Disease Control and Prevention (CDC) and the US Federal Bureau of Investigation (FBI) during a two-year period from June 1, 2009 and May 31, 2011. Results identified 297 electronic news media reports, 538 CDC reports, and 384 FBI reports of unknown “white powder.” This study showed different unknown “white powder” incidents captured by each of the three sources. However, the authors could not determine the public health implications of this discordance. PMID:25420771

  4. Status of Shortnose Sturgeon in the Potomac River. Part 1: Field Studies

    USGS Publications Warehouse

    Kynard, Boyd; Breece, Matthew; Atcheson, Megan; Kieffer, Micah; Mangold, Mike

    2007-01-01

    Field studies during more than 3 years (March 2004–July 2007) collected data on life history of Potomac River shortnose sturgeon Acipenser brevirostrum to understand their biological status in the river. We sampled intensively for adults using gill nets, but captured only one adult in 2005. Another adult was captured in 2006 by a commercial fisher. Both fish were females with excellent body and fin condition, both had mature eggs, and both were telemetrytagged to track their movements. The lack of capturing adults, even when intensive netting was guided by movements of tracked fish, indicated abundance of the species was less than in any river known with a sustaining population of the species. Telemetry tracking of the two females (one during September 2005–July 2007, one during March 2006–February 2007) found they remained in the river for all the year, not for just a few months like sturgeons on a coastal migration. Further, one fish used the same freshwater reach during three summers. The two sturgeons used different reaches during some seasons, with one fish using saline water more than the other. The adults homed to small reaches in the same month each year, like shortnose sturgeon in their natal river. The total reach used by tracked sturgeons was 124 km (rkm 63–187), of which the lowermost 78 km, which was used for summering and wintering, contained the freshwater: saltwater interface. The most upstream reach used (rkm 185–187) contained potential spawning habitat. This reach was visited by one female on a pre-spawning migration in April 2006, but spawning was likely unsuccessful. Water quality (dissolved oxygen and temperature) in the summering–wintering reach was adequate all the year, although during the summer it was minimally acceptable. We periodically recaptured the same tagged female and found she healed well after tagging, appeared healthy in body and fins, grew well, and rapidly matured a new clutch of eggs. All surveys indicated adults

  5. Sensitivity of shovelnose sturgeon (Scaphirhynchus platorynchus) and pallid sturgeon (S. albus) early life stages to 3,30,4,40,5-pentachlorobiphenyl and 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure

    USGS Publications Warehouse

    Buckler, Justin; Candrl, James S.; McKee, Michael J.; Papoulias, Diana M.; Tillitt, Donald E.; Galat, David L.

    2015-01-01

    Concern exists that polychlorinated biphenyls (PCBs) may be contributing to the current decline of shovelnose sturgeon (Scaphirhynchus platorynchus) and the US federally endangered pallid sturgeon (Scaphirhynchus albus). Waterborne exposures with newly fertilized eggs were used to assess developmental and morphological effects of 2 of the most potent aryl hydrocarbon receptor (AhR) agonists, 3,30,4,40,5-pentachlorobiphenyl (PCB-126) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), on early life stage shovelnose and pallid sturgeon. No dose-related effects of PCB-126 were observed on percent development or hatch in either species at concentrations as high as 1711 ng/g egg. Effects of TCDD on percent development were not assessed in shovelnose sturgeon. However, percent development was not affected by TCDD in pallid sturgeon, and percent hatch was unaffected by TCDD doses as high as 60 ng/g egg to 81 ng/g egg in either species. Morphological pathologies such as yolk sac edema and craniofacial deformities were typical of AhR agonist exposure and were similar in both species. Calculated PCB-126 50% lethal dose (LD50, 95% fiducial limits) values were 196 ng/ g egg (188–203 ng/g) for shovelnose and 159 ng/g egg (122–199 ng/g) for pallid sturgeon. Likewise, calculated TCDD LD50 values were 13 ng/g egg (11–15 ng/g) for shovelnose and 12 ng/g egg (10–14 ng/g) for pallid sturgeon. These LD50 values are among the highest recorded in early life stage fish, suggesting that early life stage Scaphirhynchus sturgeon may be comparatively insensitive to AhR agonists.

  6. Sensitivity of shovelnose sturgeon (Scaphirhynchus platorynchus) and pallid sturgeon (S. albus) early life stages to 3,3',4,4',5-pentachlorobiphenyl and 2,3,7,8-tetrachlorodibenzo-P-dioxin exposure.

    PubMed

    Buckler, Justin; Candrl, James S; McKee, Michael J; Papoulias, Diana M; Tillitt, Donald E; Galat, David L

    2015-06-01

    Concern exists that polychlorinated biphenyls (PCBs) may be contributing to the current decline of shovelnose sturgeon (Scaphirhynchus platorynchus) and the US federally endangered pallid sturgeon (Scaphirhynchus albus). Waterborne exposures with newly fertilized eggs were used to assess developmental and morphological effects of 2 of the most potent aryl hydrocarbon receptor (AhR) agonists, 3,3',4,4',5-pentachlorobiphenyl (PCB-126) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), on early life stage shovelnose and pallid sturgeon. No dose-related effects of PCB-126 were observed on percent development or hatch in either species at concentrations as high as 1711 ng/g egg. Effects of TCDD on percent development were not assessed in shovelnose sturgeon. However, percent development was not affected by TCDD in pallid sturgeon, and percent hatch was unaffected by TCDD doses as high as 60 ng/g egg to 81 ng/g egg in either species. Morphological pathologies such as yolk sac edema and craniofacial deformities were typical of AhR agonist exposure and were similar in both species. Calculated PCB-126 50% lethal dose (LD50, 95% fiducial limits) values were 196 ng/g egg (188-203 ng/g) for shovelnose and 159 ng/g egg (122-199 ng/g) for pallid sturgeon. Likewise, calculated TCDD LD50 values were 13 ng/g egg (11-15 ng/g) for shovelnose and 12 ng/g egg (10-14 ng/g) for pallid sturgeon. These LD50 values are among the highest recorded in early life stage fish, suggesting that early life stage Scaphirhynchus sturgeon may be comparatively insensitive to AhR agonists.

  7. New investigations around CYP11A1 and its possible involvement in an androstenone QTL characterised in Large White pigs

    PubMed Central

    2011-01-01

    Background Previously, in boars with extreme androstenone levels, differential expression of the CYP11A1 gene in the testes has been characterised. CYP11A1 is located in a region where a QTL influencing boar fat androstenone levels has been detected in a Large White pig population. Clarifying the role of CYP11A1 in boar taint is important because it catalyses the initial step of androstenone synthesis and also of steroid synthesis. Results A genome-wide association study located CYP11A1 at approximately 1300 kb upstream from SNP H3GA0021967, defining the centre of the region containing the QTL for androstenone variation. In this study, we partially sequenced the CYP11A1 gene and identified several new single nucleotide polymorphisms (SNP) within it. Characterisation of one animal, heterozygous for CYP11A1 testicular expression but homozygous for a haplotype of a large region containing CYP11A1, revealed that variation of CYP11A1 expression is probably regulated by a mutation located downstream from the SNP H3GA0021967. We analysed CYP11A1 expression in LW families according to haplotypes of the QTL region's centre. Effects of haplotypes on CYP11A1 expression and on androstenone accumulation were not concordant. Conclusion This study shows that testicular expression of CYP11A1 is not solely responsible for the QTL influencing boar fat androstenone levels. As a conclusion, we propose to refute the hypothesis that a single mutation located near the centre of the QTL region could control androstenone accumulation in fat by regulating the CYP11A1 expression. PMID:21504607

  8. Brain ventricle development in H. huso (Beluga sturgeon) larvae.

    PubMed

    Tavighi, S H; Saadatfar, Z; Shojaei, B; Rassouli, M Behnam

    2016-09-01

    The development of ventricles in the brain of H. huso (Beluga sturgeon) from 1 to 54 days old is presented in this study. The components observed in the 1-day-old ventricular system were the telencephalic, tectal, and cerebellar ventricles. These ventricles were not observed to have any recess or sulcus. They were surrounded by copious ependymal and embryonic cells. Two different parts were detected in the 6-day-old telencephalic ventricle: the olfactory and lateral ventricle. The olfactory ventricle was observed as a cranial extension of the telencephalic ventricle from 6 days old, as was the inner cell layer of the olfactory bulb (ic) adjacent to this extension. In the preoptic region, the lateral ventricle was connected to the preoptic recess from 15 days old, and this recess was connected by the interventricular foramen to the third ventricle in the diencephalon. At 6 days old, the third ventricle in the diencephalon was visible at the caudal part of the lateral ventricle, and the third ventricle had a recess near to the inferior lobe of the hypothalamus. At 6 days old, the tectal ventricle was observed to have bilateral extensions which proceeded to grow with age. The cerebellar ventricle, situated between the two lobes of the cerebellum, was observed from 1 day old. The cerebellar ventricle grew with age, extending laterally from 6 days old. The connection of the cerebellar ventricle to the fourth ventricle in the medulla oblongata was visible from 6 days old. Upon dividing the ventricular system into three regions (forebrain, midbrain, and hindbrain), stereological studies performed utiizing Cavalieri's principle indicated that the forebrain ventricular region had the smallest volume while the hindbrain ventricular region had the largest.

  9. Effects of acoustic tag implantation on lake sturgeon Acipenser fulvescens: lack of evidence for changes in behavior

    USGS Publications Warehouse

    Hondorp, Darryl W.; Holbrook, Christopher; Krueger, Charles C.

    2015-01-01

    An assumption of studies using acoustic telemetry is that surgical implantation of acoustic transmitters or tags does not alter behavior of tagged individuals. Evaluating the validity of this assumption can be difficult for large fish, such as adult sturgeons, not amenable to controlled laboratory experimentation. The purpose of this study was to determine if and when this assumption was valid for adult lake sturgeon Acipenser fulvescens tagged with large (34 g) acoustic transmitters and released into the St. Clair River during 2011–2014. The hypothesis that activity and reach-scale distributions of tagged and untagged lake sturgeon did not differ was tested by comparing movement frequencies, movement rates (speed-over-ground), and location-specific detection probabilities between newly-tagged lake sturgeon and presumably fully-recovered conspecifics tagged and released in prior years.

  10. Identifying structural elements needed for development of a predictive life-history model for pallid and shovelnose sturgeons

    USGS Publications Warehouse

    Wildhaber, Mark L.; DeLonay, A.J.; Papoulias, D.M.; Galat, D.L.; Jacobson, R.B.; Simpkins, D.G.; Braaten, P.J.; Korschgen, C.E.; Mac, M.J.

    2011-01-01

    Intensive management of the Missouri and Mississippi Rivers has resulted in dramatic changes to the river systems and their biota. These changes have been implicated in the decline of the pallid sturgeon (Scaphirhynchus albus), which has been listed as a United States federal endangered species. The sympatric shovelnose sturgeon (S. platorynchus) is more common and widespread but has also been in decline. The decline of pallid sturgeon is considered symptomatic of poor reproductive success and low or no recruitment. In order to organize information about these species and provide a basis for future development of a predictive model to help guide recovery efforts, we present an expert-vetted, conceptual life-history framework that incorporates the factors that affect reproduction, growth, and survival of shovelnose and pallid sturgeons.

  11. Stable Carbon Isotope Evidence for Reduced Feeding of Gulf of Mexico Sturgeon during Their Prolonged River Residence Period

    NASA Astrophysics Data System (ADS)

    Gu, B.; Schell, D. M.; Frazer, T.; Hoyer, M.; Chapman, F. A.

    2001-09-01

    Stable carbon isotope ratios were used to delineate food sources for Gulf of Mexico sturgeon ( Acipenser oxyrinchus de sotoi), an anadromous fish that migrates between Gulf of Mexico and the coastal rivers in south-east U.S.A. The large difference in isotope ratios (˜11‰) between freshwater food sources and fish muscle tissue suggests that the Gulf of Mexico sturgeon do not feed significantly in fresh waters. Isotope ratio data from this study and also from the literature indicate that the growth of Gulf of Mexico sturgeon is almost entirely supported by coastal marine food sources. It is likely that Gulf of Mexico sturgeon use the cool springs that seep into the river as a thermal refuge during their river residence in summer and that thermal barriers may prevent the fish from exploiting the rich food sources available in the warmer portions of the Suwannee River.

  12. Functional C1q is present in the skin mucus of Siberian sturgeon (Acipenser baerii).

    PubMed

    Fan, Chunxin; Wang, Jian; Zhang, Xuguang; Song, Jiakun

    2015-01-01

    The skin mucus of fish acts as the first line of self-protection against pathogens in the aquatic environment and comprises a number of innate immune components. However, the presence of the critical classical complement component C1q, which links the innate and adaptive immune systems of mammalians, has not been explored in a primitive actinopterygian fish. In this study, we report that C1q is present in the skin mucus of the Siberian sturgeon (Acipenser baerii). The skin mucus was able to inhibit the growth of Escherichia coli. The bacteriostatic activity of the skin mucus was reduced by heating and by pre-incubation with EDTA or mouse anti-human C1q antibody. We also detected C1q protein in skin mucus using the western blot procedure and isolated a cDNA that encodes the Siberian sturgeon C1qC, which had 44.7-51.4% identity with C1qCs in teleosts and tetrapods. A phylogenetic analysis revealed that Siberian sturgeon C1qC lies at the root of the actinopterygian branch and is separate from the tetrapod branch. The C1qC transcript was expressed in many tissues as well as in skin. Our data indicate that C1q is present in the skin mucus of the Siberian sturgeon to protect against water-borne bacteria, and the C1qC found in the sturgeon may represent the primitive form of teleost and tetrapod C1qCs.

  13. Modeling spatial and temporal variation of suitable nursery habitats for Atlantic sturgeon in the Chesapeake Bay

    NASA Astrophysics Data System (ADS)

    Niklitschek, Edwin J.; Secor, David H.

    2005-07-01

    For rare and endangered species, bioenergetics modeling can represent a valuable approach for understanding issues of habitat value and connectivity among potential habitats within nurseries in restoration programs. We used multivariable bioenergetics and survival models for Atlantic sturgeon to generate spatially explicit maps of potential production in the Chesapeake Bay. For the period 1993-2002, spatial and temporal patterns in water quality effects (temperature, dissolved oxygen [DO] and salinity) on potential production were evaluated. In addition, two forecasted scenarios were modeled: one implementing newly revised U.S. Environmental Protection Agency (EPA) DO-criteria for the Chesapeake Bay, and the other assuming a bay-wide increase of 1 °C due to an underlying trend in regional climate. Atlantic sturgeon's low (survival/growth) tolerance to temperatures >28 °C was a critical constraint during their first 1-2 summers of life. Hatched in freshwater (spring to mid-summer), young-of-the-year were predicted to occupy cooler (deeper) areas as temperature approached sub-lethal levels. While most thermal refuges were located down-estuary, a large fraction of potential refuges were unsuitable due to persistent hypoxia and/or salinity levels beyond the limited osmoregulatory capabilities of early juvenile Atlantic sturgeon. As a result, suitable summer habitats for juvenile Atlantic sturgeons in the Chesapeake Bay were predicted to be spatially restricted and variable between years, ranging from 0 to 35% of the modeled bay surface area. In critical (drought) years, almost no summer habitat was predicted to be available for juvenile Atlantic sturgeon. Value and size of nursery habitat was highly sensitive to climatic oscillations and anthropogenic interventions affecting freshwater inflow, water temperature and/or DO. Achieving EPA DO-criteria for the Chesapeake Bay was predicted to increase total suitable habitat by 13% for an average year, while increasing

  14. Electronic tagging of green sturgeon reveals population structure and movement among estuaries

    USGS Publications Warehouse

    Lindley, S.T.; Erickson, D.L.; Moser, M.L.; Williams, G.; Langness, O.P.; McCovey, B.W.; Belchik, M.; Vogel, D.; Pinnix, W.; Kelly, J.T.; Heublein, J.C.; Klimley, A.P.

    2011-01-01

    Green sturgeon Acipenser medirostris spend much of their lives outside of their natal rivers, but the details of their migrations and habitat use are poorly known, which limits our understanding of how this species might be affected by human activities and habitat degradation.We tagged 355 green sturgeon with acoustic transmitters on their spawning grounds and in known nonspawning aggregation sites and examined their movement among these sites and other potentially important locations using automated data-logging hydrophones. We found that green sturgeon inhabit a number of estuarine and coastal sites over the summer, including the Columbia River estuary, Willapa Bay, Grays Harbor, and the estuaries of certain smaller rivers in Oregon, especially the Umpqua River estuary. Green sturgeon from different natal rivers exhibited different patterns of habitat use; most notably, San Francisco Bay was used only by Sacramento River fish, while the Umpqua River estuary was used mostly by fish from the Klamath and Rogue rivers. Earlier work, based on analysis of microsatellite markers, suggested that the Columbia River mixed stock was mainly composed of fish from the Sacramento River, but our results indicate that fish from the Rogue and Klamath River populations frequently use the Columbia River as well. We also found evidence for the existence of migratory contingentswithin spawning populations.Our findings have significant implications for the management of the threatened Sacramento River population of green sturgeon, which migrates to inland waters outside of California where anthropogenic impacts, including fisheries bycatch and water pollution, may be a concern. Our results also illustrate the utility of acoustic tracking to elucidate the migratory behavior of animals that are otherwise difficult to observe. ?? American Fisheries Society 2011.

  15. An Evaluation of a Court-Mandated Batterer Intervention Program: Investigating Differential Program Effect for African American and White Women

    ERIC Educational Resources Information Center

    Carney, Michelle Mohr; Buttell, Frederick P.

    2006-01-01

    Objective: The purpose of this study is to (a) evaluate a 16-week batterer intervention program by investigating changes in psychological variables related to abuse between pretreatment and posttreatment assessments in a sample of women involuntarily placed in treatment and (b) to investigate the differential effectiveness of this same batterer…

  16. Egg White Phantoms for HIFU

    SciTech Connect

    Divkovic, Gabriela; Jenne, Juergen W.

    2005-03-28

    We used fresh egg white and polyacrylamide to create a transparent tissue mimicking phantom. Heating of phantoms by HIFU leads to egg white protein denaturation and creation of visible white lesions. We measured the acoustical and thermal properties and investigated the possibility to use such phantoms to study the lesion formation during the HIFU therapy.

  17. Asteroseismology of White Dwarf Stars

    NASA Technical Reports Server (NTRS)

    Hansen, Carl J.

    1997-01-01

    The primary purpose of this investigation has been to study various aspects of multimode pulsations in variable white dwarfs. In particular, nonlinear interactions among pulsation modes in white dwarfs (and, to some extent, in other variable stars), analysis of recent observations where such interactions are important, and preliminary work on the effects of crystallization in cool white dwarfs are reported.

  18. Hydraulic and Substrate Maps of Reaches Used by Sturgeon (Genus Scaphirhynchus) in the Lower Missouri River, 2005-07

    USGS Publications Warehouse

    Reuter, Joanna M.; Jacobson, Robert B.; Elliott, Caroline M.; Johnson, Harold E.; DeLonay, Aaron J.

    2008-01-01

    This report is a repository of reach-scale maps of hydraulic and substrate characteristics generated for the habitat-use portion of an interdisciplinary sturgeon research project on the Lower Missouri River (from Gavins Point Dam to the junction with the Mississippi River). The maps were derived from hydroacoustic data sets that were collected for the purpose of assessing physical aquatic habitat in the vicinity of locations of adult shovelnose sturgeon (Scaphirhynchus platorynchus) and pallid sturgeon (S. albus). Hydroacoustic data sets were collected at the reach scale (mean reach length, 2.4 kilometers) in order to include the immediate vicinity of a targeted sturgeon location as well as the full range of habitat available at the bend and crossover scale. Reaches typically were surveyed on the day following the relocation of a telemetered sturgeon and at a discharge within 10 percent of the discharge on the sturgeon relocation date in order to characterize as closely as possible the channel morphology and flow-field conditions at the time that the sturgeon was present. One hundred fifty-three reaches were mapped during April-September in the years 2005 through 2007, with the majority of data collection occurring in the months of May and June (coinciding with the period of sturgeon migration and spawning in the Lower Missouri River). Interpolated maps (grid cell size, 5 meters) depict depth, generalized substrate, and depth-averaged velocity. Side-scan sonar imagery is also available for a subset of reaches. Collectively, the maps represent more than 20 percent of the length of the Lower Missouri River.

  19. Investigation of a Quantitative Method for the Analysis of Chiral Monoterpenes in White Wine by HS-SPME-MDGC-MS of Different Wine Matrices.

    PubMed

    Song, Mei; Xia, Ying; Tomasino, Elizabeth

    2015-01-01

    A valid quantitative method for the analysis of chiral monoterpenes in white wine using head-space solid phase micro-extraction-MDGC-MS (HS-SPME-MDGC-MS) with stable isotope dilution analysis was established. Fifteen compounds: (S)-(-)-limonene, (R)-(+)-limonene, (+)-(2R,4S)-cis-rose oxide, (-)-(2S,4R)-cis-rose oxide, (-)-(2R,4R)-trans-rose oxide, (+)-(2S,4S)-cis-rose oxide, furanoid (+)-trans-linalool oxide, furanoid (-)-cis-linalool oxide, furanoid (-)-trans-linalool oxide, furanoid (+)-cis-linalool oxide, (-)-linalool, (+)-linalool, (-)-α-terpineol, (+)-α-terpineol and (R)-(+)-β-citronellol were quantified. Two calibration curves were plotted for different wine bases, with varying residual sugar content, and three calibration curves for each wine base were investigated during a single fiber's lifetime. This was needed as both sugar content and fiber life impacted the quantification of the chiral terpenes. The chiral monoterpene content of six Pinot Gris wines and six Riesling wines was then analyzed using the verified method. ANOVA with Tukey multiple comparisons showed significant differences for each of the detected chiral compounds in all 12 wines. PCA score plots showed a clear separation between the Riesling and Pinot Gris wines. Riesling wines had greater number of chiral terpenes in comparison to Pinot Gris wines. Beyond total terpene content it is possible that the differences in chiral terpene content may be driving the aromatic differences in white wines.

  20. Comparison of chocolate to cacao-free white chocolate in Parkinson's disease: a single-dose, investigator-blinded, placebo-controlled, crossover trial.

    PubMed

    Wolz, Martin; Schleiffer, Christine; Klingelhöfer, Lisa; Schneider, Christine; Proft, Florian; Schwanebeck, Uta; Reichmann, Heinz; Riederer, Peter; Storch, Alexander

    2012-11-01

    A previous questionnaire study suggests an increased chocolate consumption in Parkinson's disease (PD). The cacao ingredient contains caffeine analogues and biogenic amines, such as β-phenylethylamine, with assumed antiparkinsonian effects. We thus tested the effects of 200 g of chocolate containing 80 % of cacao on UPDRS motor score after 1 and 3 h in 26 subjects with moderate non-fluctuating PD in a mono-center, single-dose, investigator-blinded crossover study using cacao-free white chocolate as placebo comparator. At 1 h after chocolate intake, mean UPDRS motor scores were mildly decreased compared to baseline in both treatments with significant results only for dark chocolate [-1.3 (95 % CI 0.18-2.52, RMANOVA F = 4.783, p = 0.013¸ Bonferroni p = 0.021 for 1 h values)]. A 2 × 2-cross-over analysis revealed no significant differences between both treatments [-0.54 ± 0.47 (95 % CI -1.50 to 0.42), p = 0.258]. Similar results were obtained at 3 h after intake. β-phenylethylamine blood levels were unaltered. Together, chocolate did not show significant improvement over white cacao-free chocolate in PD motor function.

  1. White submarine

    NASA Astrophysics Data System (ADS)

    While not everyone gets to live in a yellow submarine, the scientific community may get to have a decommissioned U.S. Navy nuclear submarine dedicated to it. The Sturgeon class of submarines, which scientists say are the ideal choice for the project, will be coming up for decommissioning in this next decade. So the time is ripe, scientists say. Two weeks ago, oceanographers, submarine specialists, marine biologists, and geophysicists, among others met at AGU headquarters in Washington to discuss how to get the project in the water. If all goes well, the project would be the "biggest thing that ever happened in ocean and Earth science," according to Lloyd Keigwin of the Woods Hole Oceanographic Institution, who convened the meeting. For example, the submarine could make many types of "compelling" research possible that can not be done now by other means, such as studies in the Arctic that may have significant bearing on global change research, Keigwin says. However, the imposing hurdles that the project must overcome are as big as the opportunities it offers. Foremost, there is a question as to who will pick up the tab for such an endeavor.

  2. A RING finger protein 114 (RNF114) homolog from Chinese sturgeon (Acipenser sinensis) possesses immune-regulation properties via modulating RIG-I signaling pathway-mediated interferon expression.

    PubMed

    Liao, Zhiyong; Chen, Xiaojun; Nie, Dongsong; Wang, Jiajia; Wu, Mingjiang

    2014-12-01

    Ubiquitin ligases play important roles in immune regulation. The human RNF114 (RING finger protein 114), an ubiquitin ligase, was recently reported to be involved in immune response to double-stranded RNA in disease pathogenesis. Here, we identified a RNF114 homolog in Chinese sturgeon (Acipenser sinensis) and investigated its potential role in immune response. The full-length cDNA of Chinese sturgeon RNF114 (csRNF114) contains an open reading frame (ORF) of 681 nucleotides coding a protein of 227 amino acids. csRNF114 shares the highest identity of 76% at amino acid level to other RNF114 homologs, clustering with bony fish RNF114s based on phylogenetic analysis. The main structural features of csRNF114, including a C3HC4 (Cys3-His-Cys4) RING domain, a C2HC (Cys2-His-Cys)-type zinc finger motif, a C2H2 (Cys2-His2)-type zinc finger motif, and a UIM (ubiquitin-interacting motif), take csRNF114 as an ubiquitin ligase. csRNF114 mRNA was widely expressed in various tissues and significantly up-regulated in poly(I:C)-treated Chinese sturgeon. Over-expression of csRNF114 in HEK293T cells significantly promoted both basal and poly(I:C)-induced activation of interferon regulatory transcription factor 3 (IRF3) and nuclear factor-κB (NF-κB) downstream retinoic acid inducible gene I (RIG-I) signaling pathway and expression of target genes type I interferon (IFN), which was nearly abolished by knockdown of RIG-I with specific human siRNA and by mutation of the C3HC4 RING domain (C28A/C31A) in csRNF114 as well. Furthermore, csRNF114 associated with ubiquitinated proteins in HEK293T cells, for which the C3HC4 RING domain was essential. These data suggested that an ubiquitin ligase RNF114 homolog with a potential role in antiviral response possibly through modulating RIG-I signaling pathway was cloned from Chinese sturgeon, which might contribute to our understanding of the immune biology of Chinese sturgeon.

  3. Raman spectroscopic and low-temperature calorimetric investigation of the low-energy vibrational dynamics of hen egg-white lysozyme

    NASA Astrophysics Data System (ADS)

    Crupi, C.; D'Angelo, G.; Wanderlingh, U.; Vasi, C.

    2011-05-01

    The low-frequency vibrational dynamics of chicken hen egg-white lysozyme were investigated using Raman spectroscopy and low-temperature calorimetry. An amorphous-like behaviour of low-frequency dynamics was observed in this protein. By using inelastic light scattering data and resorting to a fitting procedure, the low-temperature specific heat trend was theoretically reproduced, confirming that, as in disordered systems, the same low-energy excitations give rise to the observed anomalies in low-frequency vibrational and low-temperature thermal properties. A further study of polarised and depolarised Raman spectra has allowed us to infer information about the symmetry of these modes. The frequency dependence of the light-vibrational coupling constant has also been analysed.