Trends in Rocky Mountain amphibians and the role of beaver as a keystone species

USGS Publications Warehouse

Hossack, Blake R.; Gould, William R.; Patla, Debra A.; Muths, Erin L.; Daley, Rob; Legg, Kristin; Corn, P. Stephen

2015-01-01

Despite prevalent awareness of global amphibian declines, there is still little information on trends for many widespread species. To inform land managers of trends on protected landscapes and identify potential conservation strategies, we collected occurrence data for five wetland-breeding amphibian species in four national parks in the U.S. Rocky Mountains during 2002–2011. We used explicit dynamics models to estimate variation in annual occupancy, extinction, and colonization of wetlands according to summer drought and several biophysical characteristics (e.g., wetland size, elevation), including the influence of North American beaver (Castor canadensis). We found more declines in occupancy than increases, especially in Yellowstone and Grand Teton national parks (NP), where three of four species declined since 2002. However, most species in Rocky Mountain NP were too rare to include in our analysis, which likely reflects significant historical declines. Although beaver were uncommon, their creation or modification of wetlands was associated with higher colonization rates for 4 of 5 amphibian species, producing a 34% increase in occupancy in beaver-influenced wetlands compared to wetlands without beaver influence. Also, colonization rates and occupancy of boreal toads (Anaxyrus boreas) and Columbia spotted frogs (Rana luteiventris) were ⩾2 times higher in beaver-influenced wetlands. These strong relationships suggest management for beaver that fosters amphibian recovery could counter declines in some areas. Our data reinforce reports of widespread declines of formerly and currently common species, even in areas assumed to be protected from most forms of human disturbance, and demonstrate the close ecological association between beaver and wetland-dependent species.

The geomorphic influences of beaver dams and failures of beaver dams

NASA Astrophysics Data System (ADS)

Butler, David R.; Malanson, George P.

2005-10-01

Uncounted millions of beaver ponds and dams existed in North America prior to European contact and colonization. These ponds acted as sediment traps that contained tens to hundreds of billions of cubic meters of sediment that would otherwise have passed through the fluvial system. Removal of beavers by overtrapping in the 16th-19th centuries severely reduced their number and the number of ponds and dams. Dam removal altered the fluvial landscape of North America, inducing sediment evacuation and entrenchment in concert with widespread reduction in the wetlands environments. Partial recovery of beaver populations in the 20th century has allowed reoccupation of the entirety of the pre-contact range, but at densities of only one-tenth the numbers. Nevertheless, modern beaver ponds also trap large volumes of sediment in the high hundred millions to low billions of cubic meters range. Failure of beaver dams is a more common phenomenon than often assumed in the literature. During the past 20 years, numerous cases of dam failure have been documented that resulted in outburst floods. These floods have been responsible for 13 deaths and numerous injuries, including significant impacts on railway lines.

Beaver ponds' impact on fluvial processes (Beskid Niski Mts., SE Poland).

PubMed

Giriat, Dorota; Gorczyca, Elżbieta; Sobucki, Mateusz

2016-02-15

Beaver (Castor sp.) can change the riverine environment through dam-building and other activities. The European beaver (Castor fiber) was extirpated in Poland by the nineteenth century, but populations are again present as a result of reintroductions that began in 1974. The goal of this paper is to assess the impact of beaver activity on montane fluvial system development by identifying and analysing changes in channel and valley morphology following expansion of beaver into a 7.5 km-long headwater reach of the upper Wisłoka River in southeast Poland. We document the distribution of beaver in the reach, the change in river profile, sedimentation type and storage in beaver ponds, and assess how beaver dams and ponds have altered channel and valley bottom morphology. The upper Wisłoka River fluvial system underwent a series of anthropogenic disturbances during the last few centuries. The rapid spread of C. fiber in the upper Wisłoka River valley was promoted by the valley's morphology, including a low-gradient channel and silty-sand deposits in the valley bottom. At the time of our survey (2011), beaver ponds occupied 17% of the length of the study reach channel. Two types of beaver dams were noted: in-channel dams and valley-wide dams. The primary effect of dams, investigated in an intensively studied 300-m long subreach (Radocyna Pond), was a change in the longitudinal profile from smooth to stepped, a local reduction of the water surface slope, and an increase in the variability of both the thalweg profile and surface water depths. We estimate the current rate of sedimentation in beaver ponds to be about 14 cm per year. A three-stage scheme of fluvial processes in the longitudinal and transverse profile of the river channel is proposed. C. fiber reintroduction may be considered as another important stage of the upper Wisłoka fluvial system development. Copyright © 2015 Elsevier B.V. All rights reserved.

Coupled stream and population dynamics: Modeling the role beaver (Castor canadensis) play in generating juvenile steelhead (Oncorhynchus mykiss) habitat

NASA Astrophysics Data System (ADS)

Jordan, C.; Bouwes, N.; Wheaton, J. M.; Pollock, M.

2013-12-01

Over the past several centuries, the population of North American Beaver has been dramatically reduced through fur trapping. As a result, the geomorphic impacts long-term beaver occupancy and activity can have on fluvial systems have been lost, both from the landscape and from our collective memory such that physical and biological models of floodplain system function neither consider nor have the capacity to incorporate the role beaver can play in structuring the dynamics of streams. Concomitant with the decline in beaver populations was an increasing pressure on streams and floodplains through human activity, placing numerous species of stream rearing fishes in peril, most notably the ESA listing of trout and salmon populations across the entirety of the Western US. The rehabilitation of stream systems is seen as one of the primary means by which population and ecosystem recovery can be achieved, yet the methods of stream rehabilitation are applied almost exclusively with the expected outcome of a static idealized stream planform, occasionally with an acknowledgement of restoring processes rather than form and only rarely with the goal of a beaver dominated riverscape. We have constructed an individual based model of trout and beaver populations that allows the exploration of fish population dynamics as a function of stream habitat quality and quantity. We based the simulation tool on Bridge Creek (John Day River basin, Oregon) where we have implemented a large-scale restoration experiment using wooden posts to provide beavers with stable platforms for dam building and to simulate the dams themselves. Extensive monitoring captured geomorphic and riparian changes, as well as fish and beaver population responses; information we use to parameterize the model as to the geomorphic and fish response to dam building beavers. In the simulation environment, stream habitat quality and quantity can be manipulated directly through rehabilitation actions and indirectly through the dynamics of the co-occurring beaver population. The model allowed to us to ask questions critical for designing restoration strategies based on dam building beaver activity, such as what beaver population growth rate is required to develop and maintain floodplain connectivity in an incised system, or what beaver population size is required to increase juvenile steelhead production? The model was sensitive to several variables including beaver colony size, dams and colony dynamics and site fidelity, and thus highlights further research needs to fill critical information gaps.

Seasonal differences in the testicular transcriptome profile of free-living European beavers (Castor fiber L.) determined by the RNA-Seq method

PubMed Central

Paukszto, Łukasz; Jastrzębski, Jan P.; Czerwińska, Joanna; Chojnowska, Katarzyna; Kamińska, Barbara; Kurzyńska, Aleksandra; Smolińska, Nina; Giżejewski, Zygmunt; Kamiński, Tadeusz

2017-01-01

The European beaver (Castor fiber L.) is an important free-living rodent that inhabits Eurasian temperate forests. Beavers are often referred to as ecosystem engineers because they create or change existing habitats, enhance biodiversity and prepare the environment for diverse plant and animal species. Beavers are protected in most European Union countries, but their genomic background remains unknown. In this study, gene expression patterns in beaver testes and the variations in genetic expression in breeding and non-breeding seasons were determined by high-throughput transcriptome sequencing. Paired-end sequencing in the Illumina HiSeq 2000 sequencer produced a total of 373.06 million of high-quality reads. De novo assembly of contigs yielded 130,741 unigenes with an average length of 1,369.3 nt, N50 value of 1,734, and average GC content of 46.51%. A comprehensive analysis of the testicular transcriptome revealed more than 26,000 highly expressed unigenes which exhibited the highest homology with Rattus norvegicus and Ictidomys tridecemlineatus genomes. More than 8,000 highly expressed genes were found to be involved in fundamental biological processes, cellular components or molecular pathways. The study also revealed 42 genes whose regulation differed between breeding and non-breeding seasons. During the non-breeding period, the expression of 37 genes was up-regulated, and the expression of 5 genes was down-regulated relative to the breeding season. The identified genes encode molecules which are involved in signaling transduction, DNA repair, stress responses, inflammatory processes, metabolism and steroidogenesis. Our results pave the way for further research into season-dependent variations in beaver testes. PMID:28678806

Suspended-sediment and turbidity responses to sediment and turbidity reduction projects in the Beaver Kill, Stony Clove Creek, and Warner Creek, Watersheds, New York, 2010–14

USGS Publications Warehouse

Siemion, Jason; McHale, Michael R.; Davis, Wae Danyelle

2016-12-05

Suspended-sediment concentrations (SSCs) and turbidity were monitored within the Beaver Kill, Stony Clove Creek, and Warner Creek tributaries to the upper Esopus Creek in New York, the main source of water to the Ashokan Reservoir, from October 1, 2010, through September 30, 2014. The purpose of the monitoring was to determine the effects of suspended-sediment and turbidity reduction projects (STRPs) on SSC and turbidity in two of the three streams; no STRPs were constructed in the Beaver Kill watershed. During the study period, four STRPs were completed in the Stony Clove Creek and Warner Creek watersheds. Daily mean SSCs decreased significantly for a given streamflow after the STRPs were completed. The most substantial decreases in daily mean SSCs were measured at the highest streamflows. Background SSCs, as measured in water samples collected in upstream reference stream reaches, in all three streams in this study were less than 5 milligrams per liter during low and high streamflows. Longitudinal stream sampling identified stream reaches with failing hillslopes in contact with the stream channel as the primary sediment sources in the Beaver Kill and Stony Clove Creek watersheds.

Quantifying the multiple, environmental benefits of reintroducing the Eurasian Beaver

NASA Astrophysics Data System (ADS)

Brazier, Richard; Puttock, Alan; Graham, Hugh; Anderson, Karen; Cunliffe, Andrew; Elliott, Mark

2016-04-01

Beavers are ecological engineers with an ability to modify the structure and flow of fluvial systems and create complex wetland environments with dams, ponds and canals. Consequently, beaver activity has potential for river restoration, management and the provision of multiple environmental ecosystem services including biodiversity, flood risk mitigation, water quality and sustainable drinking water provision. With the current debate surrounding the reintroduction of beavers into the United Kingdom, it is critical to monitor the impact of beavers upon the environment. We have developed and implemented a monitoring strategy to quantify the impact of reintroducing the Eurasian Beaver on multiple environmental ecosystem services and river systems at a range of scales. First, the experimental design and preliminary results will be presented from the Mid-Devon Beaver Trial, where a family of beavers has been introduced to a 3 ha enclosure situated upon a first order tributary of the River Tamar. The site was instrumented to monitor the flow rate and quality of water entering and leaving the site. Additionally, the impacts of beavers upon riparian vegetation structure, water/carbon storage were investigated. Preliminary results indicate that beaver activity, particularly the building of ponds and dams, increases water storage within the landscape and moderates the river response to rainfall. Baseflow is enhanced during dry periods and storm flow is attenuated, potentially reducing the risk of flooding downstream. Initial analysis of water quality indicates that water entering the site (running off intensively managed grasslands upslope), has higher suspended sediment loads and nitrate levels, than that leaving the site, after moving through the series of beaver ponds. These results suggest beaver activity may also act as a means by which the negative impact of diffuse water pollution from agriculture can be mitigated thus providing cleaner water in rivers downstream. Secondly, the River Otter Beaver Trial will be discussed. In 2015 Natural England granted a five year licence to monitor beavers living wild upon the River Otter, Devon. The River Otter, ca. 280 km2, is a dynamic, spatey system with downstream areas exhibiting poor ecological status, primarily due to sediment and phosphorus loading, which both impact on fish numbers. The impacts of Eurasian Beaver upon English river systems are currently poorly understood, with the outcome of this pilot study having significant implications for river restoration and management. This project, the first of its kind in England, is monitoring the impacts of beavers upon the River Otter catchment with three main scientific objectives: (1) Characterise the existing structure of the River Otter riparian zone and quantify any changes during the 2015-2019 period; (2) Quantify the impact of beaver activity on water flow at a range of scales in the Otter catchment; (3) Evaluate the impact of beaver activity on water quality. Finally, lessons learnt from these monitoring programs will be discussed in light of the need for more natural solutions to flood and diffuse pollution management. We conclude that whilst our work demonstrates multiple positive benefits of Beaver reintroduction, considerably more, scale-appropriate monitoring is required before such results could be extrapolated to landscape scales.

Captive care and welfare considerations for beavers.

PubMed

Campbell-Palmer, Róisín; Rosell, Frank

2015-01-01

Beavers (Castor spp.) tend not to be a commonly held species and little published material exists relating to their captive care. We review published material and discuss husbandry issues taking into account the requirements of wild beavers. As social mammals with complex chemical communication systems and with such an ability to modify their environments, studies of wild counterparts suggest the captive requirements of beavers may actually be more sophisticated than generally perceived. Common field techniques may have practical application in the captive setting. Their widespread utilisation in conservation, including reintroductions, translocations and habitat management, also requires components of captive care. As welfare science advances there is increasing pressure on captive collections to improve standards and justify the keeping of animals. Conservation science is increasingly challenged to address individual welfare standards. Further research focusing on the captive care of beavers is required. © 2015 Wiley Periodicals, Inc.

Influence of Beaver Dams on Channel Complexity, Hydrology, and Temperature Regime in a Mountainous Stream

NASA Astrophysics Data System (ADS)

Majerova, M.; Neilson, B. T.; Schmadel, N. M.; Wheaton, J. M.; Snow, C. J.

2013-12-01

Beaver dams and beaver activity affect hydrologic processes, sediment transport, channel complexity and water quality of streams. Beaver ponds, which form behind beaver dams, increase in-channel water storage affecting the timing and volume of flow and resulting in the attenuation and flattening of the hydrograph. Channel complexity also increases the potential for transient storage (both surface and subsurface) and influences stream temperature. Impacts of beaver dams and beaver activity on stream responses are difficult to quantify because responses are dynamic and spatially variable. Few studies have focused on the reach scale temporal influences on stream responses and further research is needed particularly in quantifying the influence of beaver dams and their role in shaping the stream habitat. This study explores the changing hydrology and temperature regime of Curtis Creek, a mountainous stream located in Northern Utah, in a 560 m long reach where groundwater exchanges and temperature differences were observed over a three-year period. We have collected continuous stream discharge, stream temperature data and performed tracer experiments. During the first year, we were able to capture the pre-beaver activity. In the second year, we captured the impacts of some beaver activity with only a few dams built in the reach, while the third year included the effects of an entire active beaver colony. By the end of the study period, a single thread channel had been transformed into a channel with side channels and backwaters at multiple locations therefore increasing channel complexity. The cumulative influence of beaver dams on reach scale discharge resulted in a slightly losing reach that developed into a gaining reach. At the smaller sub-reach scale, both losing to gaining and gaining to losing transformations were observed. Temperature differences showed a warming effect of beaver dams at the reach scale. The reach stream temperature difference increased on average 0.3°C when comparing the first to the third year of our study period. This warming trend was more pronounced in summer stream temperatures where differences were about 0.7°C. During winter months cooling was observed and temperatures decreased about -0.2°C over the reach. Annual tracer studies also captured an 81min (238%) increase in residence times due primarily to the increased channel complexity and storage over the three-year period. Our study provides reach scale understanding regarding the temporal influence of beavers to not only change physical template of the channel, but also influence the hydrology and temperature regime of streams.

Using Seismic Refraction and Ground Penetrating Radar (GPR) to Characterize the Valley Fill in Beaver Meadows, Rocky Mountain National Park

NASA Astrophysics Data System (ADS)

Kramer, N.; Harry, D. L.; Wohl, E. E.

2010-12-01

This study is one of the first to use near surface geophysical techniques to characterize the subsurface stratigraphy in a high alpine, low gradient valley with a past glacial history and to obtain a preliminary grasp on the impact of Holocene beaver activity. Approximately 1 km of seismic refraction data and 5 km of GPR data were collected in Beaver Meadows, Rocky Mountain National Park. An asymmetric wedge of sediment ranging in depth from 0-20 m transverse to the valley profile was identified using seismic refraction. Complementary analysis of the GPR data suggests that the valley fill can be subdivided into till deposited during the Pleistocene glaciations and alluvium deposited during the Holocene. Two main facies were identified in the GPR profiles through pattern recognition. Facie Fd, which consists of chaotic discontinuous reflectors with an abundance of diffractions, is interpreted to be glacial till. Facie Fc, which is a combination of packages of complex slightly continuous reflectors interfingered with continuous horizontal to subhorizontal reflectors, is interpreted to be post-glacial alluvium and includes overbank, pond and in-channel deposits. Fc consistently overlies Fd throughout the study area and is no more than 7 m thick in the middle of the valley. The thickness of Holocene sedimentation (<7 m) is much less than the total amount of valley fill identified in the seismic refraction survey (0-20 m). A subfacie of Fc, Fch, which has reflectors with long periods was identified within Fc and is interpreted to be ponded sediments. The spatial distribution of facie Fch, along with: slight topographical features resembling buried beaver dams, a high abundance of fine sediment including silts and clays, historical records of beavers, and the name "Beaver Meadows" all suggest that Holocene beaver activity played a large role in sediment accumulation at this site, despite the lack of surficial relict beaver dams containing wood.

A rare Uroglena bloom in Beaver Lake, Arkansas, spring 2015

USGS Publications Warehouse

Green, William R.; Hufhines, Brad

2017-01-01

A combination of factors triggered a Uroglena volvox bloom and taste and odor event in Beaver Lake, a water-supply reservoir in northwest Arkansas, in late April 2015. Factors contributing to the bloom included increased rainfall and runoff containing increased concentrations of dissolved organic carbon, followed by a stable pool, low nutrient concentrations, and an expansion of lake surface area and littoral zone. This was the first time U. volvox was identified in Beaver Lake and the first time it was recognized as a source of taste and odor. Routine water quality samples happened to be collected by the US Geological Survey and the Beaver Water District throughout the reservoir during the bloom—. Higher than normal rainfall in March 2015 increased the pool elevation in Beaver Lake by 2.3 m (by early April), increased the surface area by 10%, and increased the littoral zone by 1214 ha; these conditions persisted for 38 days, resulting from flood water being retained behind the dam. Monitoring programs that cover a wide range of reservoir features, including dissolved organic carbon, zooplankton, and phytoplankton, are valuable in explaining unusual events such as this Uroglena bloom.

Transition to independence by subadult beavers (Castor canadensis) in an unexploited, exponentially growing population

USGS Publications Warehouse

DeStefano, S.; Koenen, Kiana K. G.; Henner, C.M.; Strules, J.

2006-01-01

We conducted a 4-year study of beavers Castor canadensis to compare the movements, survival and habitat of adults established in existing colonies to juveniles dispersing to new sites in a region with high beaver densities along a suburban-rural gradient. Estimates of annual survival were high for adult and juvenile beavers. Of nine known mortalities, seven (78%) were juveniles. Mortalities occurred during spring-summer, and none during fall-winter. There was a trend toward higher-to-lower survival along the suburban-rural gradient, respectively. Human-induced mortality (e.g. trapping and shooting) was higher in rural areas, whereas nonhuman-induced mortality (e.g. disease, accidents) was higher in suburban areas. Fifteen (14 subadults and one adult) beavers moved from natal colonies to other areas. The average dispersal distance for subadults was 4.5 km (SE = 1.0) along streams or rivers, or 3.5 km (SE = 0.7) straight-line point-to-point. Most dispersal movements were made in spring (April-June). In two cases, individual subadults made return movements from their dispersal sites back to their natal colonies. Dispersal sites tended to be in smaller, shallower wetlands or streams and in areas with higher overstorey canopy closure compared with natal colonies. Woody vegetation usually preferred by beavers for food tended to be less common at dispersal sites than at natal colonies. In regions with high densities of beaver, dispersing juveniles are likely to attempt to colonize lower quality sites. High densities of beavers also lead to more human-beaver conflicts and, in Massachusetts, the pest control management options in place during the past decade have been ineffectual at controlling population levels. Alternately, in regions with no beavers or very low densities and where reintroductions are being attempted, the landscape matrix surrounding release sites should include suitable sites for dispersing young to establish colonies.

Final Environmental Assessment Prescribed Burning for Weed Management on F. E. Warren Air Force Base, Wyoming

DTIC Science & Technology

2012-04-01

most prevalent noxious weeds found at F. E. Warren AFB. · Fish and Wildlife Fish species that have been stocked in the Pearson Lakes include brown ... trout , rainbow trout , lake trout , catfish , perch , and fathead minnow. Aquatic furbearers on the base include beaver and muskrat. Beavers are found

The hydrological modeling in terms of determining the potential European beaver effect

NASA Astrophysics Data System (ADS)

Szostak, Marta; Jagodzińska, Jadwiga

2017-06-01

The objective of the paper was the hydrological analysis, in terms of categorizing main watercourses (based on coupled catchments) and marking areas covered by potential impact of the occurrence and activities of the European beaver Castor fiber. At the analysed area - the Forest District Głogów Małopolski there is a population of about 200 beavers in that Forest District. Damage inflicted by beavers was detected on 33.0 ha of the Forest District, while in the area of 13.9 ha the damage was small (below 10%). The monitoring of the beavers' behaviour and the analysis of their influence on hydrology of the area became an important element of using geoinformationtools in the management of forest areas. ArcHydro ArcGIS Esri module was applied, as an integrated set of tools for hydrographical analysis and modelling. Further steps of the procedure are hydrologic analyses such as: marking river networks on the DTM, filling holes, making maps of the flow direction, making the map of the accumulation flow, defining and segmentation of streams, marking elementary basins, marking coupled basins, making dams in the places, where beavers occur and localization of the area with a visible impact of damming. The result of the study includes maps prepared for the Forest District: the map of main rivers and their basins, categories of watercourses and compartments particularly threatened by beaver's foraging.

Beaver damming, fluvial geomorphology, and climate in Yellowstone National Park, Wyoming

NASA Astrophysics Data System (ADS)

Persico, L.; Meyer, G.

2008-12-01

Beaver habitation is an important component of many fluvial landscapes that can impact a variety of hydrologic, geomorphic, and ecologic processes. Beaver damming, via long term valley aggradation, is thought to be important to the postglacial geomorphic evolution of many smaller mountain stream networks in the western United States. Loss of beaver dams can also cause rapid channel incision. Although several studies have documented rapid short-term aggradation of channels behind single beaver dams, there is little actual data on the long-term cumulative effect of beaver damming. In Yellowstone''s Northern Range, field surveys and stratigraphic section along six streams in the Northern Range reveal net thickness of mostly <2 m and patchy distribution of Holocene beaver-pond deposits. We estimate that reaches with clear morphologic and stratigraphic evidence for beaver-related aggradation constitute about 19% of the total stream network length. Reaches with probable and possible beaver-related aggradation make up an additional 8% and 2% of the network, respectively. The remaining 71% of the network has no clear evidence for beaver-related aggradation. Thirty-nine radiocarbon ages on beaver-pond deposits in northern Yellowstone fall primarily within the last 4000 yr, but gaps in dated beaver occupation from 2200-1800 and 950-750 cal yr BP correspond with severe and persistent droughts that likely caused low to ephemeral discharges in smaller streams. In the last two decades, severe drought has also caused streams that were occupied by beaver in the 1920s to become ephemeral. Beaver have been largely absent from the Northern Range since the mid-20th century, probably due to multiple ecological and climatic factors. This loss of beaver is thought to have led to widespread degradation of stream and riparian habitat via channel incision. Although 20th-century beaver loss has caused significant channel incision at some former dam sites, downcutting elsewhere in northern Yellowstone is unrelated to beaver dams or predates historic beaver extirpation. Overall, historic incision affects a 26% of reaches that have experienced beaver related aggradation in the study area. These results highlight the importance of historical and Holocene geomorphic studies in understanding the role of beaver in landscape dynamics.

RESEARCH: Attitudes of Private- and Public-Land Managers in Wyoming, USA, Toward Beaver.

PubMed

McKINSTRY; ANDERSON

1999-01-01

/ A mail survey concerning beaver (Castor canadensis) management in Wyoming, USA, was sent to 5265 private-land managers and 124 public-land managers during 1993. The survey was developed in response to increasing interest in beaver management and beaver reintroduction possibilities. Private-land managers responding to the survey supplied information on 62,859 km2 of land area and 20,037 km of streams. Primary concerns about beaver damage centered on (in decreasing order of importance) blocked irrigation ditches, girdled timber, blocked culverts, and flooded pastures, roads, crops, and timber. Primary benefits that landowners perceive that beaver give them were, in order of importance, elevated water tables, increased riparian vegetation, and increased stock-watering opportunities. Public-land managers also listed these benefits and detriments among their top concerns for beaver. Over 45% of landowners with beaver on their property and all of the public-land managers displayed an interest in a beaver reintroduction program and in more proactive beaver management. KEY WORDS: Beaver; Beaver management; Castor canadensis; Landowners; Mail surveys; Wildlife values; Wildlife damage

Do beaver dams reduce habitat connectivity and salmon productivity in expansive river floodplains?

PubMed

Malison, Rachel L; Kuzishchin, Kirill V; Stanford, Jack A

2016-01-01

Beaver have expanded in their native habitats throughout the northern hemisphere in recent decades following reductions in trapping and reintroduction efforts. Beaver have the potential to strongly influence salmon populations in the side channels of large alluvial rivers by building dams that create pond complexes. Pond habitat may improve salmon productivity or the presence of dams may reduce productivity if dams limit habitat connectivity and inhibit fish passage. Our intent in this paper is to contrast the habitat use and production of juvenile salmon on expansive floodplains of two geomorphically similar salmon rivers: the Kol River in Kamchatka, Russia (no beavers) and the Kwethluk River in Alaska (abundant beavers), and thereby provide a case study on how beavers may influence salmonids in large floodplain rivers. We examined important rearing habitats in each floodplain, including springbrooks, beaver ponds, beaver-influenced springbrooks, and shallow shorelines of the river channel. Juvenile coho salmon dominated fish assemblages in all habitats in both rivers but other species were present. Salmon density was similar in all habitat types in the Kol, but in the Kwethluk coho and Chinook densities were 3-12× lower in mid- and late-successional beaver ponds than in springbrook and main channel habitats. In the Kol, coho condition (length: weight ratios) was similar among habitats, but Chinook condition was highest in orthofluvial springbrooks. In the Kwethluk, Chinook condition was similar among habitats, but coho condition was lowest in main channel versus other habitats (0.89 vs. 0.99-1.10). Densities of juvenile salmon were extremely low in beaver ponds located behind numerous dams in the orthofluvial zone of the Kwethluk River floodplain, whereas juvenile salmon were abundant in habitats throughout the entire floodplain in the Kol River. If beavers were not present on the Kwethluk, floodplain habitats would be fully interconnected and theoretically could produce 2× the biomass (between June-August, 1,174 vs. 667 kg) and rear 3× the number of salmon (370,000 vs. 140,000) compared to the existing condition with dams present. The highly productive Kol river produces an order of magnitude more salmon biomass and rears 40× the individuals compared to the Kwethluk. If beavers were introduced to the Kol River, we estimate that off-channel habitats would produce half as much biomass (2,705 vs. 5,404 kg) and 3× fewer individuals (1,482,346 vs. 4,856,956) owing to conversion of inter-connected, productive springbrooks into inaccessible pond complexes. We concluded that beaver dams may limit the total amount of floodplain habitat available for salmon rearing in the Kwethluk river and that the introduction of beavers to the Kol river could be detrimental to salmon populations. The introduction of beavers to other large alluvial rivers like those found in Kamchatka could have negative consequences for salmon production.

Do beaver dams reduce habitat connectivity and salmon productivity in expansive river floodplains?

PubMed Central

Kuzishchin, Kirill V.; Stanford, Jack A.

2016-01-01

Beaver have expanded in their native habitats throughout the northern hemisphere in recent decades following reductions in trapping and reintroduction efforts. Beaver have the potential to strongly influence salmon populations in the side channels of large alluvial rivers by building dams that create pond complexes. Pond habitat may improve salmon productivity or the presence of dams may reduce productivity if dams limit habitat connectivity and inhibit fish passage. Our intent in this paper is to contrast the habitat use and production of juvenile salmon on expansive floodplains of two geomorphically similar salmon rivers: the Kol River in Kamchatka, Russia (no beavers) and the Kwethluk River in Alaska (abundant beavers), and thereby provide a case study on how beavers may influence salmonids in large floodplain rivers. We examined important rearing habitats in each floodplain, including springbrooks, beaver ponds, beaver-influenced springbrooks, and shallow shorelines of the river channel. Juvenile coho salmon dominated fish assemblages in all habitats in both rivers but other species were present. Salmon density was similar in all habitat types in the Kol, but in the Kwethluk coho and Chinook densities were 3–12× lower in mid- and late-successional beaver ponds than in springbrook and main channel habitats. In the Kol, coho condition (length: weight ratios) was similar among habitats, but Chinook condition was highest in orthofluvial springbrooks. In the Kwethluk, Chinook condition was similar among habitats, but coho condition was lowest in main channel versus other habitats (0.89 vs. 0.99–1.10). Densities of juvenile salmon were extremely low in beaver ponds located behind numerous dams in the orthofluvial zone of the Kwethluk River floodplain, whereas juvenile salmon were abundant in habitats throughout the entire floodplain in the Kol River. If beavers were not present on the Kwethluk, floodplain habitats would be fully interconnected and theoretically could produce 2× the biomass (between June–August, 1,174 vs. 667 kg) and rear 3× the number of salmon (370,000 vs. 140,000) compared to the existing condition with dams present. The highly productive Kol river produces an order of magnitude more salmon biomass and rears 40× the individuals compared to the Kwethluk. If beavers were introduced to the Kol River, we estimate that off-channel habitats would produce half as much biomass (2,705 vs. 5,404 kg) and 3× fewer individuals (1,482,346 vs. 4,856,956) owing to conversion of inter-connected, productive springbrooks into inaccessible pond complexes. We concluded that beaver dams may limit the total amount of floodplain habitat available for salmon rearing in the Kwethluk river and that the introduction of beavers to the Kol river could be detrimental to salmon populations. The introduction of beavers to other large alluvial rivers like those found in Kamchatka could have negative consequences for salmon production. PMID:27635357

Biology Today: Of Wishbones, Beavers & Blinking.

ERIC Educational Resources Information Center

Flannery, Maura, Ed.

1989-01-01

Provided is a discussion of items covering a variety of fascinating biological topics which include: the elasticity of the furcula of starlings in flight, beavers increasing the greenhouse effect, effective invaders, traveling birds, the cuckoo deception, competitive sperm, hearing springs, heat and sight, blinking as punctuation, mutations, and…

75 FR 40034 - Northeastern Tributary Reservoirs Land Management Plan, Beaver Creek, Clear Creek, Boone, Fort...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-13

... shoreline along these reservoirs. Existing land uses around the reservoirs include TVA project operations... TENNESSEE VALLEY AUTHORITY Northeastern Tributary Reservoirs Land Management Plan, Beaver Creek, Clear Creek, Boone, Fort Patrick Henry, South Holston, Watauga, and Wilbur Reservoirs, Tennessee and...

Beaver (Castor canadensis) in heavily browsed environments

USGS Publications Warehouse

Baker, Bruce W.

2003-01-01

Beaver (Castor canadensis) populations have declined or failed to recover in heavily browsed environments. I suggest that intense browsing by livestock or ungulates can disrupt beaver-willow (Salix spp.) mutualisms that likely evolved under relatively low herbivory in a more predator-rich environment, and that this interaction may explain beaver and willow declines. Field experiments in Rocky Mountain National Park, Colorado, USA, found the interaction of beaver and elk (Cervus elaphus) herbivory suppressed compensatory growth in willow. Intense elk browsing of simulated beaver-cut willow produced plants which were small and hedged with a high percentage of dead stems, whereas protected plants were large and highly branched with a low percentage of dead stems. Evaluation of a winter food cache showed beaver had selected woody stems with a lower percentage of leaders browsed by elk. A lack of willow stems suitable as winter beaver food may cause beaver populations to decline, creating a negative feedback mechanism for beaver and willow. In contrast, if browsing by livestock or ungulates can be controlled, and beaver can disperse from a nearby source population, then beaver may build dams in marginal habitat which will benefit willow and cause a positive riparian response that restores proper function to degraded habitat. In a shrub-steppe riparian ecosystem of northwestern Colorado, USA, rest from overgrazing of livestock released herbaceous vegetation initiating restoration of a beaver-willow community. Thus, competition from livestock or ungulates can cause beaver and willow to decline and can prevent their restoration in heavily browsed riparian environments, but beaver and willow populations can recover under proper grazing management.

Meta-analysis of environmental effects of beaver in relation to artificial dams

NASA Astrophysics Data System (ADS)

Ecke, Frauke; Levanoni, Oded; Audet, Joachim; Carlson, Peter; Eklöf, Karin; Hartman, Göran; McKie, Brendan; Ledesma, José; Segersten, Joel; Truchy, Amélie; Futter, Martyn

2017-11-01

Globally, artificial river impoundment, nutrient enrichment and biodiversity loss impair freshwater ecosystem integrity. Concurrently, beavers, ecosystem engineers recognized for their ability to construct dams and create ponds, are colonizing sites across the Holarctic after widespread extirpation in the 19th century, including areas outside their historical range. This has the potential to profoundly alter hydrology, hydrochemistry and aquatic ecology in both newly colonized and recolonized areas. To further our knowledge of the effects of beaver dams on aquatic environments, we extracted 1366 effect sizes from 89 studies on the impoundment of streams and lakes. Effects were assessed for 16 factors related to hydrogeomorphology, biogeochemistry, ecosystem functioning and biodiversity. Beaver dams affected concentrations of organic carbon in water, mercury in water and biota, sediment conditions and hydrological properties. There were no overall adverse effects caused by beaver dams or ponds on salmonid fish. Age was an important determinant of effect magnitude. While young ponds were a source of phosphorus, there was a tendency for phosphorus retention in older systems. Young ponds were a source methylmercury in water, but old ponds were not. To provide additional context, we also evaluated similarities and differences between environmental effects of beaver-constructed and artificial dams (767 effect sizes from 75 studies). Both are comparable in terms of effects on, for example, biodiversity, but have contrasting effects on nutrient retention and mercury. These results are important for assessing the role of beavers in enhancing and/or degrading ecological integrity in changing Holarctic freshwater systems.

Competition favors elk over beaver in a riparian willow ecosystem

USGS Publications Warehouse

Baker, B.W.; Peinetti, H.R.; Coughenour, M.C.; Johnson, T.L.

2012-01-01

Beaver (Castor spp.) conservation requires an understanding of their complex interactions with competing herbivores. Simulation modeling offers a controlled environment to examine long-term dynamics in ecosystems driven by uncontrollable variables. We used a new version of the SAVANNA ecosystem model to investigate beaver (C. Canadensis) and elk (Cervus elapses) competition for willow (Salix spp.). We initialized the model with field data from Rocky Mountain National Park, Colorado, USA, to simulate a 4-ha riparian ecosystem containing beaver, elk, and willow. We found beaver persisted indefinitely when elk density was or = 30 elk km_2. The loss of tall willow preceded rapid beaver declines, thus willow condition may predict beaver population trajectory in natural environments. Beaver were able to persist with slightly higher elk densities if beaver alternated their use of foraging sites in a rest-rotation pattern rather than maintained continuous use. Thus, we found asymmetrical competition for willow strongly favored elk over beaver in a simulated montane ecosystem. Finally, we discuss application of the SAVANNA model and mechanisms of competition relative to beaver persistence as metapopulations, ecological resistance and alternative state models, and ecosystem regulation.

Evidence for the importance of ductile shear in regional fabric development in Grenville-age gneisses of the Beaver Creek region, Northwest Lowlands, New York State

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tewksbury, B.; Culbertson, H.; Marcoline, J.

1993-03-01

In the Beaver Creek region of the Northwest Lowlands, Brown (1989) has described Grenville-age metasedimentary and metaigneous rocks as showing a prominent regional foliation, early southeastward emplacement of a nappe complex (the North Gouverneur Nappe), 2 subsequent generations of folds, and late regional faulting along the Beaver Creek, Pleasant Lake, and Hickory-Mud Lakes faults. The authors examined a variety of units across the Beaver Creek region, including a granitic augen gneiss immediately west of the Beaver Creek Fault Zone, an alaskitic gneiss immediately below Brown's (1989) North Gouverneur Nappe Sole Fault, a biotitic granitic gneiss within the body of Brown'smore » North Gouverneur Nappe, and hornblende augen gneisses and metasediments adjacent to the granitic gneisses. Each of the granitic units has moderately well-developed to extremely well-developed quartz ribbon lineations, and all show at least 2 ductile shear fabrics. Shear fabrics are present as well in the hornblende augen gneisses but are essentially absent in most of the metasedimentary lithologies, even those immediately adjacent to well-lineated, sheared granitic gneiss. The earliest shear fabrics exhibit spectacular quartz ribbon lineations, sigma grains, and, in the hornblende augen gneiss, shear bands. Granitic gneisses in the Beaver Creek Region show shear fabrics in addition to the main fabric in the rock. A second, variably-recovered shear fabric with quartz ribbons and well-developed sigma grains with core and mantle structure overprints the main shear fabric and shows largely the same sense of shear. The authors suggest further that a regional kinematic model for the Beaver Creek region must take into account significant, protracted regional shear, perhaps including formation of sheath folds, as in the Hyde School Gneiss at Payne Lake and Dobbs Creek.« less

BOREAS TGB-5 Dissolved Organic Carbon Data from NSA Beaver Ponds

NASA Technical Reports Server (NTRS)

Bourbonniere, Rick; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor)

2000-01-01

The BOReal Ecosystem-Atmosphere Study Trace Gas Biogeochemistry (BOREAS TGB-5) team collected several data sets related to carbon and trace gas fluxes and concentrations in the Northern Study Area (NSA). This data set contains concentrations of dissolved organic and inorganic carbon species from water samples collected at various NSA sites. In particular, this set covers the NSA Tower Beaver Pond Site and the NSA Gillam Road Beaver Pond Site, including data from all visits to open water sampling locations during the BOREAS field campaigns from April to September 1994. The data are provided in tabular ASCII files.

Simulation modeling to understand how selective foraging by beaver can drive the structure and function of a willow community

USGS Publications Warehouse

Peinetti, H.R.; Baker, B.W.; Coughenour, M.B.

2009-01-01

Beaver-willow (Castor-Salix) communities are a unique and vital component of healthy wetlands throughout the Holarctic region. Beaver selectively forage willow to provide fresh food, stored winter food, and construction material. The effects of this complex foraging behavior on the structure and function of willow communities is poorly understood. Simulation modeling may help ecologists understand these complex interactions. In this study, a modified version of the SAVANNA ecosystem model was developed to better understand how beaver foraging affects the structure and function of a willow community in a simulated riparian ecosystem in Rocky Mountain National Park, Colorado (RMNP). The model represents willow in terms of plant and stem dynamics and beaver foraging in terms of the quantity and quality of stems cut to meet the energetic and life history requirements of beaver. Given a site where all stems were equally available, the model suggested a simulated beaver family of 2 adults, 2 yearlings, and 2 kits required a minimum of 4 ha of willow (containing about10 stems m-2) to persist in a steady-state condition. Beaver created a willow community where the annual net primary productivity (ANPP) was 2 times higher and plant architecture was more diverse than the willow community without beaver. Beaver foraging created a plant architecture dominated by medium size willow plants, which likely explains how beaver can increase ANPP. Long-term simulations suggested that woody biomass stabilized at similar values even though availability differed greatly at initial condition. Simulations also suggested that willow ANPP increased across a range of beaver densities until beaver became food limited. Thus, selective foraging by beaver increased productivity, decreased biomass, and increased structural heterogeneity in a simulated willow community.

Do beavers promote the invasion of non-native Tamarix in the Grand Canyon riparian zone

USGS Publications Warehouse

Mortenson, S.G.; Weisberg, P.J.; Ralston, B.E.

2008-01-01

Beavers (Castor canadensis Kuhl) can influence the competitive dynamics of plant species through selective foraging, collection of materials for dam creation, and alteration of hydrologic conditions. In the Grand Canyon National Park, the native Salix gooddingii C.R.Ball (Goodding's willow) and Salix exigua Nutt. (coyote willow) are a staple food of beavers. Because Salix competes with the invasive Tamarix ramosissima Ledeb., land mangers are concerned that beavers may cause an increase in Tamarix through selective foraging of Salix. A spatial analysis was conducted to assess whether the presence of beavers correlates with the relative abundance of Salix and Tamarix. These methods were designed to detect a system-wide effect of selective beaver foraging in this large study area (367 linear km of riparian habitat). Beavers, Salix, and Tamarix co-occurred at the broadest scales because they occupied similar riparian habitat, particularly geomorphic reaches of low and moderate resistivity. Once the affinity of Salix for particular reach types was accounted for, the presence of Salix was independent of beaver distribution. However, there was a weak positive association between beaver presence and Salix cover. Salix was limited to geomorphic settings with greater sinuosity and distinct terraces, while Tamarix occurred in sinuous and straighter sections of river channel (cliffs, channel margins) where it dominated the woody species composition. After accounting for covariates representing river geomorphology, the proportion of riparian surfaces covered by Tamarix was significantly greater for sites where beavers were present. This indicates that either Tamarix and beavers co-occur in similar habitats, beavers prefer habitats that have high Tamarix cover, or beavers contribute to Tamarix dominance through selective use of its native woody competitors. The hypothesis that beaver herbivory contributes to Tamarix dominance should be considered further through more mechanistic studies of beaver foraging processes and long-term plant community response. ?? 2008 The Society of Wetland Scientists.

Beaver herbivory on aquatic plants.

PubMed

Parker, John D; Caudill, Christopher C; Hay, Mark E

2007-04-01

Herbivores have strong impacts on marine and terrestrial plant communities, but their impact is less well studied in benthic freshwater systems. For example, North American beavers (Castor canadensis) eat both woody and non-woody plants and focus almost exclusively on the latter in summer months, yet their impacts on non-woody plants are generally attributed to ecosystem engineering rather than herbivory. Here, we excluded beavers from areas of two beaver wetlands for over 2 years and demonstrated that beaver herbivory reduced aquatic plant biomass by 60%, plant litter by 75%, and dramatically shifted plant species composition. The perennial forb lizard's tail (Saururus cernuus) comprised less than 5% of plant biomass in areas open to beaver grazing but greater than 50% of plant biomass in beaver exclusions. This shift was likely due to direct herbivory, as beavers preferentially consumed lizard's tail over other plants in a field feeding assay. Beaver herbivory also reduced the abundance of the invasive aquatic plant Myriophyllum aquaticum by nearly 90%, consistent with recent evidence that native generalist herbivores provide biotic resistance against exotic plant invasions. Beaver herbivory also had indirect effects on plant interactions in this community. The palatable plant lizard's tail was 3 times more frequent and 10 times more abundant inside woolgrass (Scirpus cyperinus) tussocks than in spatially paired locations lacking tussocks. When the protective foliage of the woolgrass was removed without exclusion cages, beavers consumed nearly half of the lizard's tail leaves within 2 weeks. In contrast, leaf abundance increased by 73-93% in the treatments retaining woolgrass or protected by a cage. Thus, woolgrass tussocks were as effective as cages at excluding beaver foraging and provided lizard's tail plants an associational refuge from beaver herbivory. These results suggest that beaver herbivory has strong direct and indirect impacts on populations and communities of herbaceous aquatic plants and extends the consequences of beaver activities beyond ecosystem engineering.

Effects of experimental floods on riparian and aquatic ecosystems: Bill Williams River, Arizona

NASA Astrophysics Data System (ADS)

Shafroth, P. B.; Andersen, D. C.; Wilcox, A. C.; Kui, L.; Stella, J. C.

2013-12-01

Development of flow prescriptions for environmental purposes along rivers is relatively common, but implementation of these 'environmental flows' occurs infrequently. Implementation is critical for testing hypotheses relating flow regime to biotic response, which ultimately can inform adaptive flow management. We describe the development of flow prescriptions and evaluate responses of riparian vegetation, beaver dams, and associated aquatic habitat to experimental floods and intervening base flows associated with an environmental flow program on the Bill Williams River (BWR), in semiarid Arizona. First, we assessed effects of flow releases between 1993 and 2009 designed to favor the establishment and maintenance of native riparian trees (Populus and Salix) and disfavor an invasive, nonnative shrub (Tamarix spp.) downstream of Alamo Dam on the BWR. Our data are multi-scaled and include a several-decade assessment of changes to major vegetation types based on a time series of aerial photography, an assessment of species composition and abundance sampled in permanent vegetation quadrats, and targeted seedling surveys following experimental floods. Between 1993 and 2009, we observed significant increases in Populus and Salix forests and essentially no change in Tamarix. Experimental floods in 2006 and 2007 resulted in higher mortality of Tamarix seedlings than Salix. These results illustrate the potential for managing streamflow to influence riparian vegetation dynamics, including management of nonnative species. Second, we examined the role of beaver as ecosystem engineers in the BWR and linkages to flow releases between 2004 and 2013. Beaver convert lotic stream habitat to lentic through dam construction and maintenance during low flow periods, and the process is reversed when a flood or other event causes dam failure. We estimated the extent of lotic and beaver-created lentic (beaver pond) habitat along the BWR and related the likelihood of damage or destruction of beaver dams to the magnitude and duration of experimental floods. We obtained counts of beaver dams at various times from aerial photographs, aerial videography, and ground surveys. The ratio of lotic to lentic stream length was approximately 6 times greater following a large flood versus a 7 year period with no significant flood releases. Floods of different magnitudes and durations resulted in notably different levels of damage or removal of beaver dams. Finally, we sampled woody vegetation adjacent to the channel to estimate the effect of beaver herbivory, and noted high levels of mature tree mortality in one of our study reaches. Results of our previous and ongoing investigations are reported to land and water managers as part of an adaptive streamflow management process.

Colonial Era Impoundment of the Northeastern United States: Beaver Trapping and Low- head Dam Construction

NASA Astrophysics Data System (ADS)

Salant, N.; Bain, D.; Brandt, S.

2008-12-01

Hydrologic systems of the northeastern United States were transformed by European settler activities. The colonial economy shifted engineered water structures from beaver dams to human dams built for power generation. While the geomorphic effects of human-constructed dams have recently garnered considerable attention, few studies have investigated how intensive trapping for the fur trade, the near extermination of the Northeast beaver population, and the consequent loss of beaver ponds altered the regional water balance. Although reconstructions of colonial beaver populations have been made, none link the decline in beavers to its hydrologic impact. Beaver population models based on pre-colonial population estimates, historic harvest rates, and current-day population dynamics were used to simulate the corresponding decrease in pond numbers over time. Beaver populations declined dramatically during the seventeenth century, with harvest rates estimated at 2,000-10,000 beavers per year, resulting in expatriation in some sub-regions by the early 1700s. Using contemporary estimates of beaver pond volumes, the calculated loss in pond storage between 1600 and 1840 was approximately 17 million cubic meters of water and sediment, considerably larger than estimated storage gains from dam construction in the same period, suggesting that beaver eradication was a major driver of hydrologic change during the colonial era.

Where and How Wolves (Canis lupus) Kill Beavers (Castor canadensis).

PubMed

Gable, Thomas D; Windels, Steve K; Bruggink, John G; Homkes, Austin T

2016-01-01

Beavers (Castor canadensis) can be a significant prey item for wolves (Canis lupus) in boreal ecosystems due to their abundance and vulnerability on land. How wolves hunt beavers in these systems is largely unknown, however, because observing predation is challenging. We inferred how wolves hunt beavers by identifying kill sites using clusters of locations from GPS-collared wolves in Voyageurs National Park, Minnesota. We identified 22 sites where wolves from 4 different packs killed beavers. We classified these kill sites into 8 categories based on the beaver-habitat type near which each kill occurred. Seasonal variation existed in types of kill sites as 7 of 12 (58%) kills in the spring occurred at sites below dams and on shorelines, and 8 of 10 (80%) kills in the fall occurred near feeding trails and canals. From these kill sites we deduced that the typical hunting strategy has 3 components: 1) waiting near areas of high beaver use (e.g., feeding trails) until a beaver comes near shore or ashore, 2) using vegetation, the dam, or other habitat features for concealment, and 3) immediately attacking the beaver, or ambushing the beaver by cutting off access to water. By identifying kill sites and inferring hunting behavior we have provided the most complete description available of how and where wolves hunt and kill beavers.

Tom Beaver, Creek Television Reporter. With Teacher's Guide. Native Americans of the Twentieth Century.

ERIC Educational Resources Information Center

Minneapolis Public Schools, MN.

A biography for elementary school students presents an account of an American Indian television reporter, Tom Beaver (Creek), and includes a map of Oklahoma showing the location of Indian tribes. A teacher's guide following the biography contains information about the Creek tribe and the history of television, learning objectives and directions…

Can beaver impact promote river renaturalization? The example of the Raba River, southern Poland.

PubMed

Gorczyca, Elżbieta; Krzemień, Kazimierz; Sobucki, Mateusz; Jarzyna, Krzysztof

2018-02-15

The European beaver (Castor fiber) was reintroduced in the Polish Carpathians in the 1980s after a few centuries of absence. It gradually colonized suitable habitats in the Raba River valley and elsewhere. The question arises as to whether beaver activity can play a role in the local improvement of hydromorphological conditions and spontaneous renaturalization of the Raba River channel. Field surveys were performed in morphodynamically and structurally homogeneous reaches of the river. Traces of beaver activity were identified and used to estimate the studied beaver population. Local beaver impact on the studied river channel was also determined. The Raba channel is trained along about 80% of its length and considerably incised. Traces of beavers activity were found in 16 out of 31 river reaches, mainly in the upper and lower river course. The study showed that relatively flat channel gradient, small maximum bed-material grain size, and high channel sinuosity favour beaver presence. The largest number of beaver habitats was identified in river reaches strongly altered by man and characterized by a uniform channel structure. Beaver impact on channel structure varies depending on differences of the river channel features in upper and lower reaches of the Raba River channel. In upper reaches, the impact of beaver activity (mostly dams) is reflected in increased lateral erosion, while slower water current reduces the tendency for bed degradation. In lower reaches, beaver impact is mostly limited to bank fragmentation (slides and burrows). Lateral erosion, accumulation of material at the toe of riverbanks, and wood debris accumulation all produce a local impact on river channel width. These beaver-initiated processes mostly alter artificially homogenized river reaches. Beavers may actually play a substantial role in future renaturalization of both upper and lower reaches of the Raba River. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of Beaver Pond Colonization History on Methylmercury Concentrations in Surface Water.

PubMed

Levanoni, Oded; Bishop, Kevin; Mckie, Brendan G; Hartman, Göran; Eklöf, Karin; Ecke, Frauke

2015-11-03

Elevated concentrations of methylmercury (MeHg) in freshwater ecosystems are of major environmental concern in large parts of the northern hemisphere. Beaver ponds have been identified as a potentially important source of MeHg. The role of beavers might be especially pronounced in large parts of Europe, where beaver populations have expanded rapidly following near-extirpation. This study evaluates the role of the age and colonization history (encompassing patterns of use and reuse) of ponds constructed by the Eurasian beaver Castor fiber in regulating MeHg concentrations in Swedish streams. In 12 beaver systems located in three regions, we quantified MeHg concentrations together with other relevant parameters on five occasions per year in 2012-2013. Five were pioneer systems, inundated for the first time since beaver extirpation, and seven were recolonized, with dams reconstructed by newly recolonizing beavers. MeHg concentrations in pioneer but not in recolonized beaver systems were up to 3.5 fold higher downstream than upstream of the ponds, and varied between seasons and years. Our results show that pioneer inundation by beavers can increase MeHg concentrations in streams, but that this effect is negligible when dams are reconstructed on previously used ponds. We therefore expect that the recovery and expansion of beavers in the boreal system will only have a transitional effect on MeHg in the environment.

Interaction of beaver and elk herbivory reduces standing crop of willow

USGS Publications Warehouse

Baker, B.W.; Mitchell, D.C.S.; Ducharme, H.C.; Stanley, T.R.; Peinetti, H.R.

2005-01-01

Populations of beaver and willow have not thrived in riparian environments that are heavily browsed by livestock or ungulates, such as elk. The interaction of beaver and elk herbivory may be an important mechanism underlying beaver and willow declines in this competitive environment. We conducted a field experiment that compared the standing crop of willow three years after simulated beaver cutting on paired plants with and without intense elk browsing (∼85% utilization rate). Simulated beaver cutting with intense elk browsing produced willow that was small (biomass and diameter) and short, with far fewer, but longer, shoots and a higher percentage of dead biomass. In contrast, simulated beaver cutting without elk browsing produced willow that was large, tall, and leafy, with many more, but shorter, shoots (highly branched) and a lower percentage of dead biomass. Total stem biomass after three years was 10 times greater on unbrowsed plants than on browsed plants. Unbrowsed plants recovered 84% of their pre-cut biomass after only two growing seasons, whereas browsed plants recovered only 6%. Thus, the interaction of beaver cutting and elk browsing strongly suppressed the standing crop of willow. We predict that a lack of willow suitable as winter food for beaver can cause beaver populations to decline, creating a feedback mechanism that reduces beaver and willow populations. Thus, intense herbivory by ungulates or livestock can disrupt beaver–willow mutualisms that naturally occur in less competitive environments.

Where and How Wolves (Canis lupus) Kill Beavers (Castor canadensis)

PubMed Central

Gable, Thomas D.; Windels, Steve K.; Bruggink, John G.; Homkes, Austin T.

2016-01-01

Beavers (Castor canadensis) can be a significant prey item for wolves (Canis lupus) in boreal ecosystems due to their abundance and vulnerability on land. How wolves hunt beavers in these systems is largely unknown, however, because observing predation is challenging. We inferred how wolves hunt beavers by identifying kill sites using clusters of locations from GPS-collared wolves in Voyageurs National Park, Minnesota. We identified 22 sites where wolves from 4 different packs killed beavers. We classified these kill sites into 8 categories based on the beaver-habitat type near which each kill occurred. Seasonal variation existed in types of kill sites as 7 of 12 (58%) kills in the spring occurred at sites below dams and on shorelines, and 8 of 10 (80%) kills in the fall occurred near feeding trails and canals. From these kill sites we deduced that the typical hunting strategy has 3 components: 1) waiting near areas of high beaver use (e.g., feeding trails) until a beaver comes near shore or ashore, 2) using vegetation, the dam, or other habitat features for concealment, and 3) immediately attacking the beaver, or ambushing the beaver by cutting off access to water. By identifying kill sites and inferring hunting behavior we have provided the most complete description available of how and where wolves hunt and kill beavers. PMID:27992441

Modeling a beaver population on the Prescott Peninsula, Massachusetts: Feasibility of LANDSAT as an input

NASA Technical Reports Server (NTRS)

Finn, J. T.; Howard, R.

1981-01-01

A preliminary dynamic model of beaver spatial distribution and population growth was developed. The feasibility of locating beaver ponds on LANDSAT digital tapes, and of using this information to provide initial conditions of beaver spatial distribution for the model, and to validate model predictions is discussed. The techniques used to identify beaver ponds on LANDSAT are described.

Hydraulic characteristics and dynamics of beaver dams in a Midwestern U.S. agricultural waershed

Treesearch

M.C. McCullough; D.E. Eisenhauer; M.G. Dosskey; D.M. Admiraal

2006-01-01

Populations of Noth America beaver (castor canadensis) have increased in the past decades throughout the Midwestern U.S., leading to an increase in the frequency of beaver dams in small streams. Beaver dams form ponds and slow water velocity. Multiple dams create a stair-step effect on the water surface profile. The hydraulic and geomorphic influence of beaver dams on...

Design to monitor trend in abundance and presence of American beaver (Castor canadensis) at the national forest scale.

PubMed

Beck, Jeffrey L; Dauwalter, Daniel C; Gerow, Kenneth G; Hayward, Gregory D

2010-05-01

Wildlife conservationists design monitoring programs to assess population dynamics, project future population states, and evaluate the impacts of management actions on populations. Because agency mandates and conservation laws call for monitoring data to elicit management responses, it is imperative to design programs that match the administrative scale for which management decisions are made. We describe a program to monitor population trends in American beaver (Castor canadensis) on the US Department of Agriculture, Black Hills National Forest (BHNF) in southwestern South Dakota and northeastern Wyoming, USA. Beaver have been designated as a management indicator species on the BHNF because of their association with riparian and aquatic habitats and its status as a keystone species. We designed our program to monitor the density of beaver food caches (abundance) within sampling units with beaver and the proportion of sampling units with beavers present at the scale of a national forest. We designated watersheds as sampling units in a stratified random sampling design that we developed based on habitat modeling results. Habitat modeling indicated that the most suitable beaver habitat was near perennial water, near aspen (Populus tremuloides) and willow (Salix spp.), and in low gradient streams at lower elevations. Results from the initial monitoring period in October 2007 allowed us to assess costs and logistical considerations, validate our habitat model, and conduct power analyses to assess whether our sampling design could detect the level of declines in beaver stated in the monitoring objectives. Beaver food caches were located in 20 of 52 sampled watersheds. Monitoring 20 to 25 watersheds with beaver should provide sufficient power to detect 15-40% declines in the beaver food cache index as well as a twofold decline in the odds of beaver being present in watersheds. Indices of abundance, such as the beaver food cache index, provide a practical measure of population status to conduct long-term monitoring across broad landscapes such as national forests.

Behavior of beaver in lakes with varying water levels in Northern Minnesota

NASA Astrophysics Data System (ADS)

Smith, Douglas W.; Peterson, Rolf O.

1991-05-01

We studied the effects of winter water drawdowns (2.3 m) on beavers in Voyageurs National Park, Minnesota, USA. Our study was designed to sample areas within the park that differed in water drawdown regime. Lodges were counted and beavers were livetrapped and radio-implanted to study behavior, movements, and mortality. Active beaver lodge density, determined by aerial survey in 1984 and 1986, was greatest along the shoreline of the drawdown reservoir. In winter beavers living on the drawdown reservoir spent less time inside their lodges than did beavers from stable water environments, foraged more above ice, and they were unable to fully use stored food. Only one case of starvation in the drawdown reservoir was documented, but beavers in reservoirs that were drawn down survived winter in poorer condition than did beavers living in areas in which water levels remained high. In spite of an increasing population and lack of widespread mortality, winter water drawdowns did alter beaver behavior. To reduce these impacts, total annual water fluctuation should not exceed 1.5 m, and winter drawdown should not exceed 0.7 m. Possible management alternatives and costs are discussed.

76 FR 13344 - Beaver Creek Landscape Management Project, Ashland Ranger District, Custer National Forest...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-11

... DEPARTMENT OF AGRICULTURE Forest Service Beaver Creek Landscape Management Project, Ashland Ranger... Impact Statement for the Beaver Creek Landscape Management Project was published in the Federal Register... Responsible Official for the Beaver Creek Landscape Management Project. DATES: The Final Environmental Impact...

Beaver dams and channel sediment dynamics on Odell Creek, Centennial Valley, Montana, USA

NASA Astrophysics Data System (ADS)

Levine, Rebekah; Meyer, Grant A.

2014-01-01

Beaver dams in streams are generally considered to increase bed elevation through in-channel sediment storage, thus, reintroductions of beaver are increasingly employed as a restoration tool to repair incised stream channels. Here we consider hydrologic and geomorphic characteristics of the study stream in relation to in-channel sediment storage promoted by beaver dams. We also document the persistence of sediment in the channel following breaching of dams. Nine reaches, containing 46 cross-sections, were investigated on Odell Creek at Red Rock Lakes National Wildlife Refuge, Centennial Valley, Montana. Odell Creek has a snowmelt-dominated hydrograph and peak flows between 2 and 10 m3 s- 1. Odell Creek flows down a fluvial fan with a decreasing gradient (0.018-0.004), but is confined between terraces along most of its length, and displays a mostly single-thread, variably sinuous channel. The study reaches represent the overall downstream decrease in gradient and sediment size, and include three stages of beaver damming: (1) active; (2) built and breached in the last decade; and (3) undammed. In-channel sediment characteristics and storage were investigated using pebble counts, fine-sediment depth measurements, sediment mapping and surveys of dam breaches. Upstream of dams, deposition of fine (≤ 2 mm) sediment is promoted by reduced water surface slope, shear stress and velocity, with volumes ranging from 48 to 182 m3. High flows, however, can readily transport suspended sediment over active dams. Variations in bed-sediment texture and channel morphology associated with active dams create substantial discontinuities in downstream trends and add to overall channel heterogeneity. Observations of abandoned dam sites and dam breaches revealed that most sediment stored above beaver dams is quickly evacuated following a breach. Nonetheless, dam remnants trap some sediment, promote meandering and facilitate floodplain development. Persistence of beaver dam sediment within the main channel on Odell Creek is limited by frequent breaching (< 1-5 years), so in-channel sediment storage because of damming has not caused measurable channel aggradation over the study period. Enhanced overbank flow by dams, however, likely increases fine-grained floodplain sedimentation and riparian habitat. Contrasts between beaver-damming impacts on Odell Creek and other stream systems of different scales suggest a high sensitivity to hydrologic, geomorphic, and environmental controls, complicating predictions of the longer-term effects of beaver restoration.

Fire effects on the Point Reyes Mountain Beaver at Point Reyes National Seashore, California

USGS Publications Warehouse

Fellers, Gary M.; Pratt, David; Griffin, Jennifer L.

2004-01-01

In October 1995, a wildlands fire burned 5,000 ha on the Point Reyes peninsula, California, USA. In most of the nonforested areas, the fire effectively cleared the ground of litter and vegetation and revealed thousands of Point Reyes mountain beaver (Aplodontia rufa phaea) burrow openings. In the first 6 months after the fire, we surveyed burned coastal scrub and riparian habitat to (1) count the number of burrow openings that existed at the time of the fire, and (2) evaluate whether signs of post-fire mountain beaver activity were evident. We estimated that only 0.4–1.7% of mountain beavers within the burn area survived the fire and immediate post-fire period. We monitored mountain beaver activity for 5 years at 8 sites where mountain beavers survived, and found little or no recovery. We estimate that the mountain beaver population will take 15–20 years post-fire to recover.

Prevalence of Microsporidia, Cryptosporidium spp., and Giardia spp. in beavers (Castor canadensis) in Massachusetts

USGS Publications Warehouse

Fayer, R.; Santin, M.; Trout, J.M.; DeStefano, S.; Koenen, K.; Kaur, T.

2006-01-01

Feces from 62 beavers (Castor canadensis) in Massachusetts were examined by fluorescence microscopy (IFA) and polymerase chain reaction (PCR) for Microsporidia species, Cryptosporidium spp., and Giardia spp. between January 2002 and December 2004. PCR-positive specimens were further examined by gene sequencing. Protist parasites were detected in 6.4% of the beavers. All were subadults and kits. Microsporidia species were not detected. Giardia spp. was detected by IFA from four beavers; Cryptosporidium spp. was also detected by IFA from two of these beavers. However, gene sequence data for the ssrRNA gene from these two Cryptosporidium spp.-positive beavers were inconclusive in identifying the species. Nucleotide sequences of the TPI, ssrRNA, and ??-giardin genes for Giardia spp. (deposited in GenBank) indicated that the four beavers were excreting Giardia duodenalis Assemblage B, the zoonotic genotype representing a potential source of waterborne Giardia spp. cysts. Copyright 2006 by American Association of Zoo Veterinarians.

77 FR 66601 - Northern Natural Gas Company; Notice of Availability of the Environmental Assessment for the...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-06

... Ochiltree, Hansford, Hutchinson, and Carson Counties, Texas; Beaver County, Oklahoma; and Kiowa and Clark... Station, Ochiltree County, Texas, MP 38.47; Beaver Compressor Station, Beaver County, Oklahoma, MP 0.00; Northern/CNG Interconnect, Beaver County, Oklahoma, MP 10.35; Englewood Branch Line, Clark County, Kansas...

Beaver Mediated Water Table Dynamics in Mountain Peatlands

NASA Astrophysics Data System (ADS)

Karran, D. J.; Westbrook, C.; Bedard-Haughn, A.

2016-12-01

Water table dynamics play an important role in the ecological and biogeochemical processes that regulate carbon and water storage in peatlands. Beaver are common in these habitats and the dams they build have been shown to raise water tables in other environments. However, the impact of beaver dams in peatlands, where water tables rest close to the surface, has yet to be determined. We monitored a network of 50 shallow wells in a Canadian Rocky Mountain peatland for 6 years. During this period, a beaver colony was maintaining a number of beaver ponds for four years until a flood event removed the colony from the area and breached some of the dams. Two more years of data were collected after the flood event to assess whether the dams enhanced groundwater storage. Beaver dams raised water tables just as they do in other environments. Furthermore, water tables within 100 meters of beaver dams were more stable than those further away and water table stability overall was greater before the flood event. Our results suggest the presence/absence of beaver in peatlands has implications for groundwater water storage and overall system function.

Hydrologic regime and herbivory stabilize an alternative state in Yellowstone National Park.

PubMed

Wolf, Evan C; Cooper, David J; Hobbs, N Thompson

2007-09-01

A decline in the stature and abundance of willows during the 20th century occurred throughout the northern range of Yellowstone National Park, where riparian woody-plant communities are key components in multiple-trophic-level interactions. The potential causes of willow decline include climate change, increased elk browsing coincident with the loss of an apex predator, the gray wolf, and an absence of habitat engineering by beavers. The goal of this study was to determine the spatial and temporal patterns of willow establishment through the 20th century and to identify causal processes. Sampled willows established from 1917 to 1999 and contained far fewer young individuals than was predicted from a modeled stable willow population, indicating reduced establishment during recent decades. Two hydrologically distinct willow establishment environments were identified: fine-grained beaver pond sediments and coarse-grained alluvium. Willows established on beaver pond sediment earlier in time, higher on floodplain surfaces, and farther from the current stream channel than did willows on alluvial sediment. Significant linear declines from the 1940s to the 1990s in alluvial willow establishment elevation and lateral distance from the stream channel resulted in a much reduced area of alluvial willow establishment. Willow establishment was not well correlated with climate-driven hydrologic variables, but the trends were consistent with the effects of stream channel incision initiated in ca. 1950, 20-30 years after beaver dam abandonment. Radiocarbon dates and floodplain stratigraphy indicate that stream incision of the present magnitude may be unprecedented in the past two millennia. We propose that hydrologic changes, stemming from competitive exclusion of beaver by elk overbrowsing, caused the landscape to transition from a historical beaver-pond and willow-mosaic state to its current alternative stable state where active beaver dams and many willow stands are absent. Because of hydrologic changes in streams, a rapid return to the historical state may not occur by reduction of elk browsing alone. Management intervention to restore the historical hydrologic regime may be necessary to recover willows and beavers across the landscape.

Fluvial wood function downstream of beaver versus man-made dams in headwater streams in Massachusetts, USA

NASA Astrophysics Data System (ADS)

David, G. C.; DeVito, L. F.; Munz, K. T.; Lisius, G.

2014-12-01

Fluvial wood is an essential component of stream ecosystems by providing habitat, increasing accumulation of organic matter, and increasing the processing of nutrients and other materials. However, years of channel alterations in Massachusetts have resulted in low wood loads despite the afforestation that has occurred since the early 1900s. Streams have also been impacted by a large density of dams, built during industrialization, and reduction of the beaver population. Beavers were reintroduced to Massachusetts in the 1940s and they have since migrated throughout the state. Beaver dams impound water, which traps sediment and results in the development of complex channel patterns and more ecologically productive and diverse habitats than those found adjacent to man-made dams. To develop better management practices for dam removal it is essential that we understand the geomorphic and ecologic function of wood in these channels and the interconnections with floodplain dynamics and stream water chemistry. We investigate the connections among fluvial wood, channel morphology, floodplain soil moisture dynamics, and stream water chemistry in six watersheds in Massachusetts that have been impacted by either beaver or man-made dams. We hypothesize that wood load will be significantly higher below beaver dams, subsequently altering channel morphology, water chemistry, and floodplain soil moisture. Reaches are surveyed up- and downstream of each type of dam to better understand the impact dams have on the fluvial system. Surveys include a longitudinal profile, paired with dissolved oxygen and ammonium measurements, cross-section and fluvial wood surveys, hydraulic measurements, and floodplain soil moisture mapping. We found that dissolved oxygen mirrored the channel morphology, but did not vary significantly between reaches. Wood loads were significantly larger downstream of beaver dams, which resulted in significant changes to the ammonium levels. Floodplain soil moisture dynamics revealed that wood loads increased the channel complexity and strengthened connections between the stream channel and floodplain. Future work will continue to explore the complex interconnections between beaver dams, channel morphology, hydraulics, floodplain dynamics and water chemistry.

Beaver Colony Density Trends on the Chequamegon-Nicolet National Forest, 1987 – 2013

PubMed Central

Ribic, Christine A.; Donner, Deahn M.; Beck, Albert J.; Reinecke, Sue; Eklund, Dan

2017-01-01

The North American beaver (Castor canadensis) is a managed species in the United States. In northern Wisconsin, as part of the state-wide beaver management program, the Chequamegon-Nicolet National Forest removes beavers from targeted trout streams on U.S. Forest Service lands. However, the success of this management program has not been evaluated. Targeted removals comprise only 3% of the annual beaver harvest, a level of effort that may not affect the beaver population. We used colony location data along Forest streams from 1987–2013 (Nicolet, northeast Wisconsin) and 1997–2013 (Chequamegon, northwest Wisconsin) to assess trends in beaver colony density on targeted trout streams compared to non-targeted streams. On the Chequamegon, colony density on non-targeted trout and non-trout streams did not change over time, while colony density on targeted trout streams declined and then stabilized. On the Nicolet, beaver colony density decreased on both non-targeted streams and targeted trout streams. However, colony density on targeted trout streams declined faster. The impact of targeted trapping was similar across the two sides of the Forest (60% reduction relative to non-targeted trout streams). Exploratory analyses of weather influences found that very dry conditions and severe winters were associated with transient reductions in beaver colony density on non-targeted streams on both sides of the Forest. Our findings may help land management agencies weigh more finely calibrated beaver control measures against continued large-scale removal programs. PMID:28081271

Beaver Colony Density Trends on the Chequamegon-Nicolet National Forest, 1987 - 2013.

PubMed

Ribic, Christine A; Donner, Deahn M; Beck, Albert J; Rugg, David J; Reinecke, Sue; Eklund, Dan

2017-01-01

The North American beaver (Castor canadensis) is a managed species in the United States. In northern Wisconsin, as part of the state-wide beaver management program, the Chequamegon-Nicolet National Forest removes beavers from targeted trout streams on U.S. Forest Service lands. However, the success of this management program has not been evaluated. Targeted removals comprise only 3% of the annual beaver harvest, a level of effort that may not affect the beaver population. We used colony location data along Forest streams from 1987-2013 (Nicolet, northeast Wisconsin) and 1997-2013 (Chequamegon, northwest Wisconsin) to assess trends in beaver colony density on targeted trout streams compared to non-targeted streams. On the Chequamegon, colony density on non-targeted trout and non-trout streams did not change over time, while colony density on targeted trout streams declined and then stabilized. On the Nicolet, beaver colony density decreased on both non-targeted streams and targeted trout streams. However, colony density on targeted trout streams declined faster. The impact of targeted trapping was similar across the two sides of the Forest (60% reduction relative to non-targeted trout streams). Exploratory analyses of weather influences found that very dry conditions and severe winters were associated with transient reductions in beaver colony density on non-targeted streams on both sides of the Forest. Our findings may help land management agencies weigh more finely calibrated beaver control measures against continued large-scale removal programs.

Beaver colony density trends on the Chequamegon-Nicolet National Forest, 1987 – 2013

USGS Publications Warehouse

Ribic, Christine; Donner, Deahn M.; Beck, Albert J.; Rugg, David J.; Reinecke, Sue; Eklund, Dan

2017-01-01

The North American beaver (Castor canadensis) is a managed species in the United States. In northern Wisconsin, as part of the state-wide beaver management program, the Chequamegon-Nicolet National Forest removes beavers from targeted trout streams on U.S. Forest Service lands. However, the success of this management program has not been evaluated. Targeted removals comprise only 3% of the annual beaver harvest, a level of effort that may not affect the beaver population. We used colony location data along Forest streams from 1987–2013 (Nicolet, northeast Wisconsin) and 1997–2013 (Chequamegon, northwest Wisconsin) to assess trends in beaver colony density on targeted trout streams compared to non-targeted streams. On the Chequamegon, colony density on non-targeted trout and non-trout streams did not change over time, while colony density on targeted trout streams declined and then stabilized. On the Nicolet, beaver colony density decreased on both non-targeted streams and targeted trout streams. However, colony density on targeted trout streams declined faster. The impact of targeted trapping was similar across the two sides of the Forest (60% reduction relative to non-targeted trout streams). Exploratory analyses of weather influences found that very dry conditions and severe winters were associated with transient reductions in beaver colony density on non-targeted streams on both sides of the Forest. Our findings may help land management agencies weigh more finely calibrated beaver control measures against continued large-scale removal programs.

Cross-species transmission of Giardia spp.: inoculation of beavers and muskrats with cysts of human, beaver, mouse, and muskrat origin.

PubMed Central

Erlandsen, S L; Sherlock, L A; Januschka, M; Schupp, D G; Schaefer, F W; Jakubowski, W; Bemrick, W J

1988-01-01

Giardia cysts isolated from humans, beavers, mice, and muskrats were tested in cross-species transmission experiments for their ability to infect either beavers or muskrats. Giardia cysts, derived from multiple symptomatic human donors and used for inoculation of beavers or muskrats, were shown to be viable by incorporation of fluorogenic dyes, excystation, and their ability to produce infections in the Mongolian gerbil model. Inoculation of beavers with 5 x 10(5) Giardia lamblia cysts resulted in the infection of 75% of the animals (n = 8), as judged by the presence of fecal cysts or intestinal trophozoites at necropsy. The mean prepatent period was 13.1 days. An infective dose experiment, using 5 x 10(1) to 5 x 10(5) viable G. lamblia cysts collected by fluorescence-activated cell sorting, demonstrated that doses of between, less than 50, and less than 500 viable cysts were required to produce infection in beavers. Scanning electron microscopy of beaver small intestine revealed that attachment of G. lamblia trophozoites produced lesions in the microvillous border. Inoculation of muskrats with G. lamblia cysts produced infections when the dose of cysts was equal to or greater than 1.25 x 10(5). The inoculation of beavers with Giardia ondatrae or Giardia muris cysts did not produce any infection; however, the administration to muskrats of Giardia cysts of beaver origin resulted in the infection of 62% of the animals (n = 8), with a prepatent period of 5 days. Our results demonstrated that beavers and muskrats could be infected with Giardia cysts derived from humans, but only by using large numbers of cysts.(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:3063208

Ecosystem engineering by invasive exotic beavers reduces in-stream diversity and enhances ecosystem function in Cape Horn, Chile.

PubMed

Anderson, Christopher B; Rosemond, Amy D

2007-11-01

Species invasions are of global significance, but predicting their impacts can be difficult. Introduced ecosystem engineers, however, provide an opportunity to test the underlying mechanisms that may be common to all invasive engineers and link relationships between changes in diversity and ecosystem function, thereby providing explanatory power for observed ecological patterns. Here we test specific predictions for an invasive ecosystem engineer by quantifying the impacts of habitat and resource modifications caused by North American beavers (Castor canadensis) on aquatic macroinvertebrate community structure and stream ecosystem function in the Cape Horn Biosphere Reserve, Chile. We compared responses to beavers in three habitat types: (1) forested (unimpacted) stream reaches, (2) beaver ponds, and (3) sites immediately downstream of beaver dams in four streams. We found that beaver engineering in ponds created taxonomically simplified, but more productive, benthic macroinvertebrate assemblages. Specifically, macroinvertebrate richness, diversity and number of functional feeding groups were reduced by half, while abundance, biomass and secondary production increased three- to fivefold in beaver ponds compared to forested sites. Reaches downstream of beaver ponds were very similar to natural forested sections. Beaver invasion effects on both community and ecosystem parameters occurred predominantly via increased retention of fine particulate organic matter, which was associated with reduced macroinvertebrate richness and diversity (via homogenization of benthic microhabitat) and increased macroinvertebrate biomass and production (via greater food availability). Beaver modifications to macroinvertebrate community structure were largely confined to ponds, but increased benthic production in beaver-modified habitats adds to energy retention and flow for the entire stream ecosystem. Furthermore, the effects of beavers on taxa richness (negative) and measures of macroinvertebrate biomass (positive) were inversely related. Thus, while a generally positive relationship between diversity and ecosystem function has been found in a variety of systems, this work shows how they can be decoupled by responding to alterative mechanisms.

Modeling intrinsic potential for beaver (Castor canadensis) habitat to inform restoration and climate change adaptation

PubMed Central

Pollock, Michael M.; Schilling, Jason W.; Olden, Julian D.; Lawler, Joshua J.; Torgersen, Christian E.

2018-01-01

Through their dam-building activities and subsequent water storage, beaver have the potential to restore riparian ecosystems and offset some of the predicted effects of climate change by modulating streamflow. Thus, it is not surprising that reintroducing beaver to watersheds from which they have been extirpated is an often-used restoration and climate-adaptation strategy. Identifying sites for reintroduction, however, requires detailed information about habitat factors—information that is not often available at broad spatial scales. Here we explore the potential for beaver relocation throughout the Snohomish River Basin in Washington, USA with a model that identifies some of the basic building blocks of beaver habitat suitability and does so by relying solely on remotely sensed data. More specifically, we developed a generalized intrinsic potential model that draws on remotely sensed measures of stream gradient, stream width, and valley width to identify where beaver could become established if suitable vegetation were to be present. Thus, the model serves as a preliminary screening tool that can be applied over relatively large extents. We applied the model to 5,019 stream km and assessed the ability of the model to correctly predict beaver habitat by surveying for beavers in 352 stream reaches. To further assess the potential for relocation, we assessed land ownership, use, and land cover in the landscape surrounding stream reaches with varying levels of intrinsic potential. Model results showed that 33% of streams had moderate or high intrinsic potential for beaver habitat. We found that no site that was classified as having low intrinsic potential had any sign of beavers and that beaver were absent from nearly three quarters of potentially suitable sites, indicating that there are factors preventing the local population from occupying these areas. Of the riparian areas around streams with high intrinsic potential for beaver, 38% are on public lands and 17% are on large tracts of privately-owned timber land. Thus, although there are a large number of areas that could be suitable for relocation and restoration using beavers, current land use patterns may substantially limit feasibility in these areas. PMID:29489853

Modeling intrinsic potential for beaver (Castor canadensis) habitat to inform restoration and climate change adaptation

USGS Publications Warehouse

Dittbrenner, Benjamin J.; Pollack, Michael M.; Schilling, Jason W.; Olden, Julian D.; Lawler, Joshua J.; Torgersen, Christian E.

2018-01-01

Through their dam-building activities and subsequent water storage, beaver have the potential to restore riparian ecosystems and offset some of the predicted effects of climate change by modulating streamflow. Thus, it is not surprising that reintroducing beaver to watersheds from which they have been extirpated is an often-used restoration and climate-adaptation strategy. Identifying sites for reintroduction, however, requires detailed information about habitat factors—information that is not often available at broad spatial scales. Here we explore the potential for beaver relocation throughout the Snohomish River Basin in Washington, USA with a model that identifies some of the basic building blocks of beaver habitat suitability and does so by relying solely on remotely sensed data. More specifically, we developed a generalized intrinsic potential model that draws on remotely sensed measures of stream gradient, stream width, and valley width to identify where beaver could become established if suitable vegetation were to be present. Thus, the model serves as a preliminary screening tool that can be applied over relatively large extents. We applied the model to 5,019 stream km and assessed the ability of the model to correctly predict beaver habitat by surveying for beavers in 352 stream reaches. To further assess the potential for relocation, we assessed land ownership, use, and land cover in the landscape surrounding stream reaches with varying levels of intrinsic potential. Model results showed that 33% of streams had moderate or high intrinsic potential for beaver habitat. We found that no site that was classified as having low intrinsic potential had any sign of beavers and that beaver were absent from nearly three quarters of potentially suitable sites, indicating that there are factors preventing the local population from occupying these areas. Of the riparian areas around streams with high intrinsic potential for beaver, 38% are on public lands and 17% are on large tracts of privately-owned timber land. Thus, although there are a large number of areas that could be suitable for relocation and restoration using beavers, current land use patterns may substantially limit feasibility in these areas.

Modeling intrinsic potential for beaver (Castor canadensis) habitat to inform restoration and climate change adaptation.

PubMed

Dittbrenner, Benjamin J; Pollock, Michael M; Schilling, Jason W; Olden, Julian D; Lawler, Joshua J; Torgersen, Christian E

2018-01-01

Through their dam-building activities and subsequent water storage, beaver have the potential to restore riparian ecosystems and offset some of the predicted effects of climate change by modulating streamflow. Thus, it is not surprising that reintroducing beaver to watersheds from which they have been extirpated is an often-used restoration and climate-adaptation strategy. Identifying sites for reintroduction, however, requires detailed information about habitat factors-information that is not often available at broad spatial scales. Here we explore the potential for beaver relocation throughout the Snohomish River Basin in Washington, USA with a model that identifies some of the basic building blocks of beaver habitat suitability and does so by relying solely on remotely sensed data. More specifically, we developed a generalized intrinsic potential model that draws on remotely sensed measures of stream gradient, stream width, and valley width to identify where beaver could become established if suitable vegetation were to be present. Thus, the model serves as a preliminary screening tool that can be applied over relatively large extents. We applied the model to 5,019 stream km and assessed the ability of the model to correctly predict beaver habitat by surveying for beavers in 352 stream reaches. To further assess the potential for relocation, we assessed land ownership, use, and land cover in the landscape surrounding stream reaches with varying levels of intrinsic potential. Model results showed that 33% of streams had moderate or high intrinsic potential for beaver habitat. We found that no site that was classified as having low intrinsic potential had any sign of beavers and that beaver were absent from nearly three quarters of potentially suitable sites, indicating that there are factors preventing the local population from occupying these areas. Of the riparian areas around streams with high intrinsic potential for beaver, 38% are on public lands and 17% are on large tracts of privately-owned timber land. Thus, although there are a large number of areas that could be suitable for relocation and restoration using beavers, current land use patterns may substantially limit feasibility in these areas.

77 FR 51559 - Notice of Intent To Prepare an Environmental Assessment for the Proposed Cameron to Milford-138...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-24

... Milford--138 kV Transmission Line Project and Possible Amendment to the Cedar Beaver Garfield Antimony... Beaver County, Utah. The proposed project would begin at the existing Cameron Substation near Beaver... Cedar Beaver Garfield Antimony RMP, approved in 1986, by changing approximately 594 acres of an existing...

Beavers as Agents of Biogeomorphic Change: A Review and Suggestions for Teaching Exercises.

ERIC Educational Resources Information Center

Butler, David R.

1991-01-01

Discusses beavers and their geomorphic impacts on their environment. Considers dam building, bank burrowing, and canal building. Suggests using the beaver as a classroom and field trip example to illustrate animals' effects on the physical landscape. Provides a review of published works on beavers in their roles as geomorphic agents. (DK)

A Review of Techniques for Minimizing Beaver and White-Tailed Deer Damage in Southern Hardwoods

Treesearch

Edward P. Hill; Douglas N. Lasher; R. Blake Roper

1978-01-01

Methods of reducing beaver and deer damage to hardwood forest resources are reviewed. Beaver controls considered were poisons, chemosterilants, predators, and trapping. Population reduction through trapping with 330 conibear traps for two weeks during two successive years effectively eliminates beaver from small watersheds and shows greater promise for control than...

Habitat and conservation status of the beaver in the Sierra San Luis Sonora, Mexico

Treesearch

Karla Pelz Serrano; Eduardo Ponce Guevara; Carlos A. Lopez Gonzalez

2005-01-01

The status of beaver (Castor canadensis) in northeastern Sonora, Mexico, is uncertain. We surveyed the Cajon Bonito River to assess the beaver’s status and habitat and found five colonies. Limiting factors appear to be pollution due to animal waste, deforestation of riparian trees, and human exploitation. Beavers did not appear to require habitat...

The Beaver: A Marine Education Infusion Unit. Northern New England Marine Education Project.

ERIC Educational Resources Information Center

Maine Univ., Orono. Coll. of Education.

This interdisciplinary unit is intended for use with third grade classes. It examines the history and economics of man's relationships to the beaver. It investigates the natural history of the beaver, its anatomy, range, food sources, and the skills it employs to modify its environment by building dams. The structure of beaver dams is examined.…

Mercury in aquatic forage of large herbivores: impact of environmental conditions, assessment of health threats, and implications for transfer across ecosystem compartments.

PubMed

Bergman, Brenda Gail; Bump, Joseph K

2014-05-01

Mercury (Hg) is a leading contaminant across U.S. water bodies, warranting concern for wildlife species that depend upon food from aquatic systems. The risk of Hg toxicity to large herbivores is little understood, even though some large herbivores consume aquatic vascular plants (macrophytes) that may hyper-accumulate Hg. We investigated whether total Hg and methylmercury (MeHg) in aquatic forage may be of concern to moose (Alces alces) and beaver (Castor canadensis) by measuring total Hg and MeHg concentrations, calculating sediment-water bioconcentration factors for macrophyte species these herbivores consume, and estimating herbivore daily Hg consumption. Abiotic factors impacting macrophyte Hg were assessed, as was the difference in Hg concentrations of macrophytes from glacial lakes and those created or expanded by beaver damming. The amount of aquatic-derived Hg that moose move from aquatic to terrestrial systems was calculated, in order to investigate the potential for movement of Hg across ecosystem compartments by large herbivores. Results indicate that the Hg exposure of generalist herbivores may be affected by macrophyte community composition more so than by many abiotic factors in the aquatic environment. Mercury concentrations varied greatly between macrophyte species, with relatively high concentrations in Utricularia vulgaris (>80 ng g(-1) in some sites), and negligible concentrations in Nuphar variegata (~6 ng g(-1)). Macrophyte total Hg concentration was correlated with water pH in predictable ways, but not with other variables generally associated with aquatic Hg concentrations, such as dissolved organic carbon. Moose estimated daily consumption of MeHg is equivalent to or below human reference levels, and far below wildlife reference levels. However, estimated beaver Hg consumption exceeds reference doses for humans, indicating the potential for sub-lethal nervous impairment. In regions of high moose density, moose may be ecologically important vectors that transfer Hg from aquatic to surrounding terrestrial systems. Copyright © 2014 Elsevier B.V. All rights reserved.

Holocene Beaver Effects on Small Streams in Yellowstone and Implications for Stream Restoration

NASA Astrophysics Data System (ADS)

Persico, L. P.; Meyer, G.

2005-12-01

It has been asserted that beaver ( Castor canadensis) damming has sustained long-term aggradation and exerted a dominant control on the morphology of small streams over much of North America. However, data on the temporal and spatial dimensions of beaver influence are extremely limited. Using beaver pond deposits and berms (abandoned dams), we document geomorphic effects of beavers on first- to fourth-order streams in semiarid-subhumid northern Yellowstone National Park, USA. Beavers were ubiquitous in the early 20th century, but are currently rare. Some formerly dammed streams have become ephemeral in recent droughts, suggesting that climate may be a significant factor controlling beaver occupation. Radiocarbon dating of wood preserved in pond deposits and berms shows notable periods of beaver activity 3655-3855, 1555-955, and 455-150 cal yr BP, but a distinct lack of activity 950-700 cal yr BP during the Medieval Climatic Anomaly, a time of severe multidecadal droughts in Yellowstone and the western USA. The spatial scale over which beavers incurred significant aggradation is controlled largely by geomorphic settings conducive to damming. Low-gradient (0.07 to 0.001) reaches with contributing areas of 4 to 70 km2 are typical for dam sites. Reaches with downstream valley constrictions are most susceptible to aggradation. Only a small fraction of the total stream length in the study area has experienced significant aggradation attributable to beaver damming, as shown by accumulations of sand and finer sediment of up to 3 m, thicker than typical overbank sediments. These sediments locally contain evidence of ponding in laminations, gleying, and high organic content. Many reaches show no evidence of any net aggradation since deglaciation. Many beaver-aggraded reaches are now incised, typically 1.5-2 m and up to 3 m. Some reaches have early Holocene (ca. 10150-8000 cal yr BP) terraces with treads ~2 m above current bankfull level, underlain by both gravelly and fine-grained fill deposits showing little evidence of ponding. Overall, these observations suggest that very high beaver populations of the early 20th century were an anomaly and that their presence in the Holocene was intermittent, with only local major impact. This counters the assumption that most stream reaches in this and similar systems have been degraded largely because of beaver abandonment.

Woody plants selected by beavers in the Appalacian Ridge and Valley Province

Treesearch

Hewlette S. Crawford; R. G. Hooper; R. F. Harlow

1976-01-01

The availability of woody plants and the selection of plants by beavers along mountain streams was studied in four areas of the Appalachian Ridge and Valley Province in Virginia. Beavers' choice of woody plants varied between areas. Many species of woody plants were cut by beavers. They climbed slopes with gradients up to 80 percent to cut trees. Large as well as...

Classification of the alterations of beaver dams to headwater streams in northeastern Connecticut, U.S.A.

NASA Astrophysics Data System (ADS)

Burchsted, Denise; Daniels, Melinda D.

2014-01-01

Of the many types of barriers to water flow, beaver dams are among the smallest, typically lasting less than a decade and rarely exceeding 1.5 m in height. They are also among the most frequent and common obstructions in rivers, with a density often exceeding ten dams per km, a frequency of construction within a given network on a time scale of years, and a historic extent covering most of North America. Past quantification of the geomorphologic impact of beaver dams has primarily been limited to local impacts within individual impoundments and is of limited geographic scope. To assess the impact of beaver dams at larger scales, this study examines channel shape and sediment distribution in thirty river reaches in northeastern Connecticut, U.S.A. The study reaches fall within the broader categories of impounded and free-flowing segments, leaving a third segment class of beaver meadows requiring additional study. Each of the study reaches were classified at the reach scale as free-flowing, valley-wide beaver pond, in-channel beaver pond, and downstream of beaver dam. The bankfull channel width to depth ratios and channel widths normalized by watershed area vary significantly across the study reach classes. Additionally, reaches modified by beaver dams have finer sediment distributions. This paper provides the first quantitative geomorphic descriptions of the in-channel beaver pond and reaches downstream of beaver dams. Given the different channel shapes and sediment distributions, we infer that geomorphic processes are longitudinally decoupled by these frequent barriers that control local base level. These barriers generate heterogeneity within a river network by greatly increasing the range of channel morphology and by generating patches controlled by different processes. Therefore, in spite of the small size of individual beaver dams, the cumulative effect of multiple dams has the potential to modify processes at larger spatial scales. To improve assessment of the larger-scale impacts, we propose a hierarchical classification scheme based on discontinuities, place the reach classes of this study within that scheme, and suggest that further research should continue investigation of discontinuity at the network scale and quantification of the cumulative impacts.

First year results from an experimental study of the ecohydrologic benefits of beaver and beaver dam analogue restoration techniques in Childs Meadow, CA

NASA Astrophysics Data System (ADS)

Yarnell, S. M.; Pope, K.; Podolak, K.; Wolf, E.; Burnett, R.

2016-12-01

Due to extensive livestock grazing and widespread removal of beaver and willows, headwater meadows have transformed from multi-thread channels with seasonally active floodplains into single thread, incised channels that store less carbon, retain less water, and are lower in habitat quality for a diverse suite of meadow-dependent wildlife. Meadow restoration techniques often include willow planting and cattle exclosures; however, few studies have rigorously tested the long-term efficacy of these methods or evaluated alternative restoration techniques such as reintroduction of beaver or installation of beaver dam analogues (BDAs). This project seeks to evaluate the installation of BDAs as a restoration technique in Childs Meadow, a heavily grazed meadow in the Cascade Range representative of low-gradient meadows across northern California. Using a before-after-control-impact study design, the study tests the impacts of two restoration techniques (willow planting with cattle exclusion and willow planting with cattle exclusion and BDAs) on hydrology, carbon sequestration, and sensitive species. Results will be compared with measurements in an unrestored section of the meadow that currently supports an active beaver population and two imperiled species (Cascades Frog and Willow Flycatcher). One specific project objective is to measure the response of hydrogeomorphic conditions (e.g. groundwater, surface water, temperature, habitat) and Cascades Frog and Willow Flycatcher to restorative actions. Pre-treatment data was collected in summer 2015, a cattle exclosure was established and willows were planted in fall 2015, and installation of the BDAs is planned for fall 2016. Three years of post-implementation monitoring will be completed to assess impacts of the treatments. Here, we will present our sampling design and first year results following initiation of the treatments.

Building a Testate Amoebae-Based Transfer Function in Mountain Fens for Paleohydrological Reconstruction Expansion

NASA Astrophysics Data System (ADS)

Lemos, A. L.; Von Ness, K.; Loisel, J.; Karran, D. J.

2017-12-01

Minerotrophic peatlands are widespread ecosystems that could be used more often as paleoecological and paleoclimatic archives. However, they have received much less attention than ombrotrophic peat bogs, resulting in very limited information pertaining to their microbial communities. In spite of this, a few studies from Europe have suggested that testate amoebae assemblages from fens could be used as proxies for soil moisture. Here we contribute to this effort by providing a new study from a mountain fen (beaver meadow) located in the Sibbald Research Wetlands in the Rocky Mountains of Kananaskis Provincial Park, Alberta, Canada. Our goals are to (1) quantify the relationships between testate amoebae communities, environmental parameters (pH, water table depth, soil moisture, conductivity, trace elements), and vegetation, (2) identify the key controls on testate amoebae distribution, and (3) develop a transfer function to be used in mountain fens of the region and potentially beyond, given the cosmopolitan nature of testate amoebae taxa. Fifty surface samples were extracted along a wide hydrological gradient in the beaver meadow during Summer 2017, including a current beaver meadow, an abandoned beaver meadow, and a site without apparent beaver activity. These sites were chosen with the hypothesis that distinct testate assemblages might colonize these different types of sites, which would be useful to reconstruct beaver activity downcore. The surface samples from these sites will be the main focus for the new transfer function and provide additional information about climate reconstruction from minerotrophic peatlands such as the mountain fen being studied here. Overall, the building of a testate amoebae-based transfer function in mountain fens is needed in order to expand and improve the use of paleohydrological reconstruction in locations of higher latitude, which are still sparse.

Giardia spp. Are Commonly Found in Mixed Assemblages in Surface Water, as Revealed by Molecular and Whole-Genome Characterization

PubMed Central

Tsui, Clement K.-M.; Hsiao, William W. L.; Uyaguari-Diaz, Miguel I.; Ho, Jordan; Tang, Patrick; Isaac-Renton, Judith

2015-01-01

Giardia is the most common parasitic cause of gastrointestinal infections worldwide, with transmission through surface water playing an important role in various parts of the world. Giardia duodenalis (synonyms: G. intestinalis and G. lamblia), a multispecies complex, has two zoonotic subtypes, assemblages A and B. When British Columbia (BC), a western Canadian province, experienced several waterborne giardiasis outbreaks due to unfiltered surface drinking water in the late 1980s, collection of isolates from surface water, as well as from humans and beavers (Castor canadensis), throughout the province was carried out. To better understand Giardia in surface water, 71 isolates, including 29 from raw surface water samples, 29 from human giardiasis cases, and 13 from beavers in watersheds from this historical library were characterized by PCR. Study isolates also included isolates from waterborne giardiasis outbreaks. Both assemblages A and B were identified in surface water, human, and beavers samples, including a mixture of both assemblages A and B in waterborne outbreaks. PCR results were confirmed by whole-genome sequencing (WGS) for one waterborne outbreak and supported the clustering of human, water, and beaver isolates within both assemblages. We concluded that contamination of surface water by Giardia is complex, that the majority of our surface water isolates were assemblage B, and that both assemblages A and B may cause waterborne outbreaks. The higher-resolution data provided by WGS warrants further study to better understand the spread of Giardia. PMID:25956776

Seasonal foraging responses of beavers to sodium-enhanced foods: An experimental assessment with field feeding trials

USGS Publications Warehouse

Strules, Jennifer; DeStefano, Stephen

2015-01-01

Salt drive is a seasonal phenomenon common to several classes of wild herbivores. Coincident with shifts of nutrient quality when plants resume growth in the spring, sodium is secondarily lost as surplus potassium is excreted. The beaver (Castor canadensis) is an herbivore whose dietary niche closely follows that of other herbivores that are subject to salt drive, but no published studies to date have assessed the likelihood of its occurrence. To quantify if beavers experience seasonal salt drive, we designed a field experiment to measure the foraging responses of beavers to sodium-enhanced foods. We used sodium-treated (salted) and control (no salt) food items (aspen [Populus tremuloides] and pine [Pinus spp.] sticks) during monthly feeding trials at beaver-occupied wetlands. If conventional ontogeny of salt drive was operant, we expected to observe greater utility of sodium-treated food items by beavers in May and June. Further, if water lilies (Nymphaea spp. and Nuphar spp.) supply beavers with sodium to meet dietary requirements as is widely speculated, we expected foraging responses to sodium-treated food items at wetlands where water lilies were absent to be greater than at wetlands where water lily was present. Aspen was selected by beavers in significantly greater amounts than pine. There was no difference between the mean percent consumed of salted and control aspen sticks by beavers at lily and non-lily wetlands, and no differences in temporal consumption associated with salted or control pine sticks at either wetland type. Salted pine was consumed in greater amounts than unsalted pine. We propose that the gastrointestinal or renal physiology of beavers may preclude solute loss, thereby preventing salt drive.

Dam busy: beavers and their influence on the structure and function of river systems

NASA Astrophysics Data System (ADS)

Larsen, J.; Larsen, A.; Lane, S. N.

2017-12-01

Beavers (Castor fiber, Castor canadensis) are the most influential mammalian ecosystem engineer, heavily modifying rivers and floodplains and influencing the hydrology, geomorphology, carbon and nutrient cycling, and ecology. They do this by constructing dams, digging canals and burrows, felling trees and introducing wood into streams, which in turn impounds water, raises shallow water tables, and alters the partitioning of the water balance, sediment transport and channel patters, biogeochemical cycling, and aquatic and terrestrial habitats. However, largely in the absence of predators, beaver numbers have been rapidly increasing throughout Europe since the 1980s, but also in parts of the US and South America, prompting a need to comprehensively review the current state of knowledge on how beavers influence the structure and function of river systems. Here, we synthesize the overall impacts on hydrology, geomorphology, biogeochemistry, and aquatic and terrestrial ecosystems. We then examine the key feedbacks and overlaps between these changes induced by beavers, finding that modifications to the longitudinal connectivity drive many key process feedbacks. However, the magnitude of these feedbacks is also heavily dependent on the landscape and climatic context, with the ability to promote lateral connectivity determining the extent of beaver impacts as stream order increases. Crucially, beavers shape a river corridor, introducing distinct processes and feedbacks that would have existed prior to the historical collapse of beaver populations. There is thus a need to adapt current river management and restoration practices such that they can accommodate and enhance the ecosystem engineering services provided by beavers. We summarize key knowledge gaps that remain in our understanding of beaver impacts, which help map an interdisciplinary future research agenda.

Modeling the Capacity of Riverscapes to Support Dam-Building Beaver

NASA Astrophysics Data System (ADS)

Macfarlane, W.; Wheaton, J. M.

2012-12-01

Beaver (Castor canadensis) dam-building activities lead to a cascade of aquatic and riparian effects that increase the complexity of streams. As a result, beaver are increasingly being used as a critical component of passive stream and riparian restoration strategies. We developed the spatially-explicit Beaver Assessment and Restoration Tool (BRAT) to assess the capacity of the landscape in and around streams and rivers to support dam-building activity for beaver. Capacity was assessed in terms of readily available nation-wide GIS datasets to assess key habitat capacity indicators: water availability, relative abundance of preferred food/building materials and stream power. Beaver capacity was further refined by: 1) ungulate grazing capacity 2) proximity to human conflicts (e.g., irrigation diversions, settlements) 3) conservation/management objectives (endangered fish habitat) and 4) projected benefits related to beaver re-introductions (e.g., repair incisions). Fuzzy inference systems were used to assess the relative importance of these inputs which allowed explicit incorporation of uncertainty resulting from categorical ambiguity of inputs into the capacity model. Results indicate that beaver capacity varies widely within the study area, but follows predictable spatial patterns that correspond to distinct River Styles and landscape units. We present a case study application and verification/validation data from the Escalante River Watershed in southern Utah, and show how the models can be used to help resource managers develop and implement restoration and conservation strategies employing beaver that will have the greatest potential to yield increases in biodiversity and ecosystem services.

The demographic response of bank-dwelling beavers to flow regulation: A comparison on the Green and Yampa rivers

USGS Publications Warehouse

Breck, S.W.; Wilson, K.R.; Andersen, D.C.

2001-01-01

We assessed the effects of flow regulation on the demography of beavers (Castor canadensis) by comparing the density, home-range size, and body size of bank-dwelling beavers on two sixth-order alluvial river systems, the flow-regulated Green River and the free-flowing Yampa River, from 1997 to 2000. Flow regulation on the Green River has altered fluvial geomorphic processes, influencing the availability of willow and cottonwood, which, in turn, has influenced the demography of beavers. Beaver density was higher on the Green River (0.5–0.6 colonies per kilometre of river) than on the Yampa River (0.35 colonies per kilometre of river). Adult and subadult beavers on the Green River were in better condition, as indicated by larger body mass and tail size. There was no detectable difference in home-range size, though there were areas on the Yampa River that no beavers used. We attribute the improved habitat quality on the Green River to a greater availability of willow. We suggest that the sandy flats and sandbars that form during base flows and the ice cover that forms over winter on the Yampa River increase the energy expended by the beavers to obtain food and increase predation risk and thus lowers the availability of woody forage.

Selected hydrologic data for the Beaver Dam Wash area, Washington County, Utah, Lincoln County, Nevada, and Mohave County, Arizona, 1991-95

USGS Publications Warehouse

Enright, Michael

1996-01-01

The hydrologic data in this report were collected in Beaver Dam Wash and adjacent areas of Washington County, Utah, Lincoln County, Nevada, andMohave County, Arizona, from 1991 to 1995; some historical data from as far back as 1932 are included for comparative purposes. The data include records of about 100 wells, drillers' and geologic logs of selected wells, and results of chemical analyses of water from wells, springs, and surface-water sites. Discharge, water temperature, and specific-conductance measurements are reported for 33 surface-water and spring sites. Daily mean discharge data are reported for two U.S. Geological Survey streamflow-gaging stations on Beaver Dam Wash (1992-95). The data were collected as part of a study done by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Resources; the Nevada Department of Conservation and Natural Resources; and the Arizona Department of Water Resources.

480mm telephoto perspective, looking south toward midspan and south anchor ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

480-mm telephoto perspective, looking south toward mid-span and south anchor arm. - Pittsburgh & Lake Erie Railroad, Ohio River Bridge, Spanning Ohio River, West of Beaver River, Beaver, Beaver County, PA

480mm telephoto perpective, looking south toward midspan and south anchor ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

480-mm telephoto perpective, looking south toward mid-span and south anchor arm. - Pittsburgh & Lake Erie Railroad, Ohio River Bridge, Spanning Ohio River, West of Beaver River, Beaver, Beaver County, PA

Using occupancy models to accommodate uncertainty in the interpretation of aerial photograph data: status of beaver in Central Oregon, USA

USGS Publications Warehouse

Pearl, Christopher A.; Adams, Michael J.; Haggerty, Patricia K.; Urban, Leslie

2015-01-01

Beavers (Castor canadensis) influence habitat for many species and pose challenges in developed landscapes. They are increasingly viewed as a cost-efficient means of riparian habitat restoration and water storage. Still, information on their status is rare, particularly in western North America. We used aerial photography to evaluate changes in beaver occupancy between 1942–1968 and 2009 in upper portions of 2 large watersheds in Oregon, USA. We used multiple observers and occupancy modeling to account for bias related to photo quality, observers, and imperfect detection of beaver impoundments. Our analysis suggested a slightly higher rate of beaver occupancy in the upper Deschutes than the upper Klamath basin. We found weak evidence for beaver increases in the west and declines in eastern parts of the study area. Our study presents a method for dealing with observer variation in photo interpretation and provides the first assessment of the extent of beaver influence in 2 basins with major water-use challenges. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

The Contribution of Tidal Fluvial Habitats in the Columbia River Estuary to the Recovery of Diverse Salmon ESUs

DTIC Science & Technology

2013-05-01

Chinook salmon (presumably subyearling) was the most prevalent life-history type detected at the Russian Island and Woody Island sites. The number of...Extend and refine the computational grid We extended the Virtual Columbia River to include regions upstream of Beaver Army, which previously served as...the Columbia River above Beaver Army and particularly above the confluence of the Willamette River. That process of calibration is highly iterative

Approaches to defining reference regimes for river restoration planning

NASA Astrophysics Data System (ADS)

Beechie, T. J.

2014-12-01

Reference conditions or reference regimes can be defined using three general approaches, historical analysis, contemporary reference sites, and theoretical or empirical models. For large features (e.g., floodplain channels and ponds) historical data and maps are generally reliable. For smaller features (e.g., pools and riffles in small tributaries), field data from contemporary reference sites are a reasonable surrogate for historical data. Models are generally used for features that have no historical information or present day reference sites (e.g., beaver pond habitat). Each of these approaches contributes to a watershed-wide understanding of current biophysical conditions relative to potential conditions, which helps create not only a guiding vision for restoration, but also helps quantify and locate the largest or most important restoration opportunities. Common uses of geomorphic and biological reference conditions include identifying key areas for habitat protection or restoration, and informing the choice of restoration targets. Examples of use of each of these three approaches to define reference regimes in western USA illustrate how historical information and current research highlight key restoration opportunities, focus restoration effort in areas that can produce the largest ecological benefit, and contribute to estimating restoration potential and assessing likelihood of achieving restoration goals.

Beaver herbivory and its effect on cottonwood trees: Influence of flooding along matched regulated and unregulated rivers

USGS Publications Warehouse

Breck, S.W.; Wilson, K.R.; Andersen, D.C.

2003-01-01

We compared beaver (Castor canadensis) foraging patterns on Fremont cottonwood (Populus deltoides subsp. wislizenii) saplings and the probability of saplings being cut on a 10 km reach of the flow-regulated Green River and a 8.6 km reach of the free-flowing Yampa River in northwestern Colorado. We measured the abundance and density of cottonwood on each reach and followed the fates of individually marked saplings in three patches of cottonwood on the Yampa River and two patches on the Green River. Two natural floods on the Yampa River and one controlled flood on the Green River between May 1998 and November 1999 allowed us to assess the effect of flooding on beaver herbivory. Independent of beaver herbivory, flow regulation on the Green River has caused a decrease in number of cottonwood patches per kilometre of river, area of patches per kilometre, and average stem density within cottonwood patches. The number of saplings cut per beaver colony was three times lower on the Green River than on the Yampa River but the probability of a sapling being cut by a beaver was still higher on the Green River because of lower sapling density there. Controlled flooding appeared to increase the rate of foraging on the Green River by inundating patches of cottonwood, which enhanced access by beaver. Our results suggest regulation can magnify the impact of beaver on cottonwood through interrelated effects on plant spatial distribution and cottonwood density, with the result that beaver herbivory will need to be considered in plans to enhance cottonwood populations along regulated rivers.

Restricted cross-scale habitat selection by American beavers.

PubMed

Francis, Robert A; Taylor, Jimmy D; Dibble, Eric; Strickland, Bronson; Petro, Vanessa M; Easterwood, Christine; Wang, Guiming

2017-12-01

Animal habitat selection, among other ecological phenomena, is spatially scale dependent. Habitat selection by American beavers Castor canadensis (hereafter, beaver) has been studied at singular spatial scales, but to date no research addresses multi-scale selection. Our objectives were to determine if beaver habitat selection was specialized to semiaquatic habitats and if variables explaining habitat selection are consistent between landscape and fine spatial scales. We built maximum entropy (MaxEnt) models to relate landscape-scale presence-only data to landscape variables, and used generalized linear mixed models to evaluate fine spatial scale habitat selection using global positioning system (GPS) relocation data. Explanatory variables between the landscape and fine spatial scale were compared for consistency. Our findings suggested that beaver habitat selection at coarse (study area) and fine (within home range) scales was congruent, and was influenced by increasing amounts of woody wetland edge density and shrub edge density, and decreasing amounts of open water edge density. Habitat suitability at the landscape scale also increased with decreasing amounts of grass frequency. As territorial, central-place foragers, beavers likely trade-off open water edge density (i.e., smaller non-forested wetlands or lodges closer to banks) for defense and shorter distances to forage and obtain construction material. Woody plants along edges and expanses of open water for predator avoidance may limit beaver fitness and subsequently determine beaver habitat selection.

Restricted cross-scale habitat selection by American beavers

PubMed Central

Taylor, Jimmy D; Dibble, Eric; Strickland, Bronson; Petro, Vanessa M; Easterwood, Christine; Wang, Guiming

2017-01-01

Abstract Animal habitat selection, among other ecological phenomena, is spatially scale dependent. Habitat selection by American beavers Castor canadensis (hereafter, beaver) has been studied at singular spatial scales, but to date no research addresses multi-scale selection. Our objectives were to determine if beaver habitat selection was specialized to semiaquatic habitats and if variables explaining habitat selection are consistent between landscape and fine spatial scales. We built maximum entropy (MaxEnt) models to relate landscape-scale presence-only data to landscape variables, and used generalized linear mixed models to evaluate fine spatial scale habitat selection using global positioning system (GPS) relocation data. Explanatory variables between the landscape and fine spatial scale were compared for consistency. Our findings suggested that beaver habitat selection at coarse (study area) and fine (within home range) scales was congruent, and was influenced by increasing amounts of woody wetland edge density and shrub edge density, and decreasing amounts of open water edge density. Habitat suitability at the landscape scale also increased with decreasing amounts of grass frequency. As territorial, central-place foragers, beavers likely trade-off open water edge density (i.e., smaller non-forested wetlands or lodges closer to banks) for defense and shorter distances to forage and obtain construction material. Woody plants along edges and expanses of open water for predator avoidance may limit beaver fitness and subsequently determine beaver habitat selection. PMID:29492032

A Model of Beaver Meadow Complex Evolution in the Silvies River Basin, Oregon.

NASA Astrophysics Data System (ADS)

Nash, C.; Grant, G.; Campbell, S. D.

2014-12-01

There is increasing evidence to suggest that the pervasive incision seen in the American West is due, in part, to the removal of beaver (Castor canadensis) in the first half of the 19th century. New restoration strategies for these systems focus on the reintroduction of beaver and construction of beaver dam analogs. Such dams locally raise streams beds and water tables, reconnect incised channels to their former floodplains, trap sediment, increase hydraulic diversity, and promote riparian vegetation. However, the geomorphic and hydrologic impacts of both the original beaver dams and their analogs are poorly understood. Observations in the Silvies River basin in Oregon, USA - an upland, semi-arid catchment with extremely high historic beaver populations and a presently recovering population, inform a conceptual model for valley floor evolution with beaver dams. The evolution of the beaver dam complex is characterized by eight stages of morphologic adjustment: water impoundment, sediment deposition, pond filling, multi-thread meadow creation, dam breaching, channel incision, channel widening, and floodplain development. Well-constructed beaver dams, given sufficient time and sediment flux, will evolve from a series of ponds to a multi-threaded channel flowing through a wet meadow complex. If a dam in the system fails, due to overtopping, undercutting, lack of maintenance, or abandonment, the upstream channel will concentrate into a single channel and incise, followed over time by widening once critical bank heights are exceeded. From stratigraphic, dendrochronologic, and geomorphic measurements, we are constraining average timescales associated with each stage's duration and transitional period. Measured sedimentation rates behind modern beaver dam analogs on five stream systems permit calculation of sediment flux over recent time periods, and aid in developing regional rates of sediment deposition over a range of drainage areas and gradients. Stratigraphic and dendrochronologic records provide insight into rates of incision, widening, and floodplain development. These measurements are leading to an understanding of the timescales associated with each morphologic stage and transition period, as well as the long-term implications of reintroducing beaver into a wide range of stream systems.

Variability of Ecosystem State in Rivers Containing Natural Dams: A Chemical Analysis

NASA Astrophysics Data System (ADS)

Reynolds, Z. A.

2015-12-01

Flooding, and the resulting economic damage to roads and property, is associated with natural dams such as beaver dams or log jams. For this reason, humans often remove natural dams; however, river reaches with natural dams provide very different ecosystem services in comparison with free-flowing river reaches. Therefore, the goal of this project is to assess the differences in ecosystem state between these different river reach types in the northeastern United States. We focused on differences in basic chemistry (e.g., dissolved oxygen, pH, temperature, and organic carbon) to assess the impact of natural dams on river ecosystem state. Study sites include rivers in the White Mountains and southeastern New Hampshire at locations with beaver dams, beaver ponds, beaver meadows, log jams, and free-flowing reaches. Dissolved oxygen, ORP, pH, temperature, and conductivity were measured in the field with a YSI Professional Plus meter. Water samples were collected for subsequent laboratory analysis of total organic carbon with a Shimadzu TOC-L. Preliminary results show that the chemistry of river water varies with feature type. Most significantly, dissolved oxygen concentrations are highest in free-flowing reaches and lowest in beaver ponds. Although beaver ponds are often associated with lower pH, due the increased concentration of organic acids, some beaver ponds can increase pH when compared to free-flowing reaches on the same river. Early results also show that water chemistry returns quickly to the chemistry typical of the free-flowing river reaches after being altered by a natural dam. Overall, natural dams create a river system that has more heterogeneity, and therefore has opportunities to provide more ecosystem functions, than a purely free-flowing river; this can increase the number of supported instream and riparian species. By increasing the understanding of how natural dams affect the chemistry of river water, river engineers can improve their decisions on how to remove problematic natural dams that increase flooding risks; they can also investigate possibilities to mimic the ecosystem state generated by natural dams in places where these dams are regularly removed.

Practical aspects of registration the transformation of a river valley by beavers using terrestrial laser scanning

NASA Astrophysics Data System (ADS)

Tyszkowski, Sebastian; Błaszkiewicz, Mirosław; Brykała, Dariusz; Gierszewski, Piotr; Kaczmarek, Halina; Kordowski, Jarosław; Słowiński, Michał

2016-04-01

Activity of beavers (Castor fiber) often significantly affects the environment in which they life. The most commonly observed effect of their being in environment is construction of beaver dams and formation a pond upstream. However, in case of a sudden break of a dam and beaver pond drainage, the valley below the dam may also undergo remodelling. The nature and magnitude of these changes depends on the quantity of water and its energy as well as on the geological structure of the valley. The effects of such events can be riverbank erosion, and the deposition of the displaced of erosion products in the form of sandbars or fans. The material can also be accumulated in local depressions or delivered to water bodies. Such events may occur multiple times in the same area. To assess their impact on the environment it is important to quantify the displaced material. The study of such transformations was performed within a small valley of the river of Struga Czechowska (Tuchola Pinewood Forest, Poland). The valley is mainly cut in sands and gravels. Its steep banks are overgrown with bushes and trees. The assessment of changes in morphology were based on the event of the beaver pond drainage of 2015. The study uses the measurements from the terrestrial laser scanning (scanner Riegl VZ-4000). The measurements were performed before and after the event. Each of the two models obtained for comparison was made up of more than 20 measurement stations. Point clouds were joined by Multi-Station Adjustment without placing in the terrain any objects of reference. During measurements attention was paid to the changes in morphology of both riverbed and valley surrounding. The paper presents the example of the recorded changes as well as the measurement procedure. Moreover, the aspects of fieldwork and issues related to post-processing, such as merging, filtering of point clouds and detection of changes, are also presented. This study is a contribution to the Virtual Institute of Integrated Climate and Landscape Evolution Analyses - ICLEA- of the Helmholtz Association, Grant No VH-VI-415.

Impact of beaver ponds on river discharge and sediment deposition along the Chevral River, Ardennes, Belgium

NASA Astrophysics Data System (ADS)

Nyssen, Jan; Frankl, Amaury; Pontzeele, Jolien; De Visscher, Maarten; Billi, Paolo

2013-04-01

With the recovery of the European beaver (Castor fiber) and their capacity to engineer fluvial landscapes, questions arise as to how they influence river discharge and sediment transport. The Chevral river (Ardennes, Belgium) contains two beaver dam sequences which appeared in 2004 and count now about 30 dams. Flow discharges and sediment fluxes were measured at the in- and outflow of each dam sequence. Volumes of sediment deposited behind the dams were measured. Between 2004 and 2011, peak flows were topped off, and the magnitude of extreme events decreased. 1710 m³ of sediment were deposited behind the beaver dams, with an average sediment thickness of 25 cm. The thickness of the sediment layer is related to the area of the beaver ponds. Along the stream, beaver pond sediment thickness displayed a sinusoidal deposition pattern, in which ponds with thick sediment layers were preceded by a series of ponds with thinner sediment layers. A downstream textural coarsening in the dam sequences was also observed, probably due to dam failures subsequent to surges. Differences in sediment flux between the in- and outflow at the beaver pond sequence were related to the river hydrograph, with deposition taking place during the rising limbs and slight erosion during the falling limbs. The seven-year-old sequences have filtered 190 tons of sediment out of the Chevral river, which is of the same order of magnitude as the 374 tons measured in pond deposits, with the difference between the values corresponding to beaver excavations (60 tons), inflow from small tributaries, and runoff from the valley flanks. Hydrogeomorphic effects of C. fiber and C. canadensis activity are similar in magnitude. The detailed analysis of changes to hydrology in beaver pond sequences confirms the potential of beavers to contribute to river and wetland restoration and catchment management.

Fire effects on the Point Reyes Mountain Beaver (Aplodontia rufa phaea) at Point Reyes National Seashore, 10 years after the Vision Fire

USGS Publications Warehouse

Fellers, Gary M.; Osbourn, Michael

2009-01-01

The 1995 Vision Fire burned 5000 ha and destroyed 40% of the habitat of the Point Reyes Mountain Beaver (Aplodontia rufa phaea). Surveys immediately post-fire and in 2000 showed that only 0.4 to 1.7% of Mountain Beavers within the burn area survived. In 2000, dense, ground-hugging Blue-blossom Ceanothus (Ceanothus thrysiflorus) appeared to make coastal scrub thickets much less suitable for Mountain Beavers even though the number of burrows at our 11 study sites had returned to 88% of pre-fire numbers. In 2005 (10 y post-fire), the habitat appeared to be better for Mountain Beavers; Blue-blossom Ceanothus had diminished and vegetation more typical of northern coastal scrub, such as Coyote Brush (Baccharis pilularis) overstory with a lower layer of herbaceous vegetation, had greatly increased; but the number of Mountain Beaver burrows had declined to 52% of pre-fire numbers and there was little change in the number of sites occupied between our 2000 and 2005 surveys. With the expected successional changes in thicket structure, Mountain Beaver populations are likely to recover further, but there will probably be considerable variation in how each population stabilizes.

Estimates of underwater and aerial visual acuity in the European beaver Castor fiber L. based on morphological data.

PubMed

Mass, A M; Supin, A Ya

2017-03-01

The eye optics and topographic distribution of ganglion cells were studied using whole mount preparations from European beaver Castor fiber L. The beaver eye optics provides emmetropia in air and hypermetropia in water. The optometrical measurements predict retinal resolution of the beaver eye around 17' in air and 9' in water. In air, retinal resolution corresponds to the real visual acuity, whereas in water, visual acuity is below the retinal resolution because of the non-precise focusing.

Impact of beaver dams on abundance and distribution of anadromous salmonids in two lowland streams in Lithuania.

PubMed

Virbickas, Tomas; Stakėnas, Saulius; Steponėnas, Andrius

2015-01-01

European beaver dams impeded movements of anadromous salmonids as it was established by fishing survey, fish tagging and redd counts in two lowland streams in Lithuania. Significant differences in abundancies of other litophilic fish species and evenness of representation by species in the community were detected upstream and downstream of the beaver dams. Sea trout parr marked with RFID tags passed through several successive beaver dams in upstream direction, but no tagged fish were detected above the uppermost dam. Increase in abundances of salmonid parr in the stream between the beaver dams and decrease below the dams were recorded in November, at the time of spawning of Atlantic salmon and sea trout, but no significant changes were detected in the sections upstream of the dams. After construction of several additional beaver dams in the downstream sections of the studied streams, abundance of Atlantic salmon parr downstream of the dams decreased considerably in comparison with that estimated before construction.

Influence of beaver activity on summer growth and condition of age-2 Atlantic salmon parr

USGS Publications Warehouse

Sigourney, Douglas B.; Letcher, B.H.; Cunjak, R.A.

2006-01-01

The activity of beavers Castor canadensis in freshwater environments can have considerable localized impacts on the physical and biological components of riparian ecosystems. By changing the habitat of a stream, beaver dams can cause spatial variation in growth opportunity that may have direct consequences for the growth of resident fish. In a small stream in eastern Canada, we studied the effects of an ephemeral beaver pond on the growth and maturity of age-2 Atlantic salmon Salmo salar parr tagged with passive integrated transponder tags. Water temperature remained relatively uniform throughout the study site. We found very little movement of recaptured fish in the study site. Fish that were recaptured in the beaver pond displayed faster summer growth rates in both length and mass than fish that were recaptured immediately above or below the pond. We also found that parr in the pond maintained relatively high condition factors, whereas fish above and below the pond appeared to decrease in condition factor throughout the summer. In addition to growth, the maturation rates of age-2 males were higher above the dam than below. This study demonstrates the effect a beaver dam can have on individual growth rates. By influencing growth during sensitive periods, the beaver pond may also influence individual life history pathways. This information could be an important component in ecosystem models that predict the effect of beaver population dynamics on the growth of individual salmonids at the landscape scale. ?? Copyright by the American Fisheries Society 2006.

Analysis of ambient conditions and simulation of hydrodynamics and water-quality characteristics in Beaver Lake, Arkansas, 2001 through 2003

USGS Publications Warehouse

Galloway, Joel M.; Green, W. Reed

2006-01-01

Beaver Lake is a large, deep-storage reservoir located in the upper White River Basin in northwestern Arkansas. The purpose of this report is to describe the ambient hydrologic and water-quality conditions in Beaver Lake and its inflows and describe a two-dimensional model developed to simulate the hydrodynamics and water quality of Beaver Lake from 2001 through 2003. Water-quality samples were collected at the three main inflows to Beaver Lake; the White River near Fayetteville, Richland Creek at Goshen, and War Eagle Creek near Hindsville. Nutrient concentrations varied among the tributaries because of land use and contributions of nutrients from point sources. The median concentrations of total ammonia plus organic nitrogen were greater for the White River than Richland and War Eagle Creeks. The greatest concentrations of nitrite plus nitrate and total nitrogen, however, were observed at War Eagle Creek. Phosphorus concentrations were relatively low, with orthophosphorus and dissolved phosphorus concentrations mostly below the laboratory reporting limit at the three sites. War Eagle Creek had significantly greater median orthophosphorus and total phosphorus concentrations than the White River and Richland Creek. Dissolved organic-carbon concentrations were significantly greater at the White River than at War Eagle and Richland Creeks. The White River also had significantly greater turbidity than War Eagle Creek and Richland Creek. The temperature distribution in Beaver Lake exhibits the typical seasonal cycle of lakes and reservoirs located within similar latitudes. Beaver Lake is a monomictic system, in which thermal stratification occurs annually during the summer and fall and complete mixing occurs in the winter. Isothermal conditions exist throughout the winter and early spring. Nitrogen concentrations varied temporally, longitudinally, and vertically in Beaver Lake for 2001 through 2003. Nitrite plus nitrate concentrations generally decreased from the upstream portion of Beaver Lake to the downstream portion and generally were greater in the hypolimnion. Total ammonia plus organic nitrogen concentrations also decreased from the upstream end of Beaver Lake to the downstream end and were substantially greater in the hypolimnion of Beaver Lake. Phosphorus concentrations mostly were near or below laboratory detection limits in the epilimnion and metalimnion in Beaver Lake and were substantially greater in the hypolimnion in the upstream and middle parts of the reservoir. Measured total and dissolved organic carbon in Beaver Lake was relatively uniform spatially, longitudinally, and vertically in the reservoir from January 2001 through December 2003. Chlorophyll a concentrations measured at sites in the upstream portion of the lake were significantly greater than at the other sites in the downstream portion of Beaver Lake. During the study period, water clarity in Beaver Lake was significantly greater at the downstream end of the reservoir than at the upstream end. The greatest Secchi depths at the downstream end of the reservoir generally were observed in 2001 compared to 2002 and 2003, but did not have a seasonal pattern as observed at sites in the middle and upstream portion of the reservoir. Similar to Secchi depth results, turbidity results indicated greater water clarity in the downstream portion of Beaver Lake compared to the upstream portion. Turbidity also was greater in the hypolimnion than in the epilimnion in the reservoir during the stratification season. A two-dimensional, laterally averaged, hydrodynamic, and water-quality model using CE-QUAL-W2 Version 3.1 was developed for Beaver Lake and calibrated based on vertical profiles of temperature and dissolved oxygen, and water-quality constituent concentrations collected at various depths at four sites in the reservoir from April 2001 to April 2003. Simulated temperatures and dissolved-oxygen concentrations compared reasonably well with measured t

Trends in base flows and extreme flows in the Beaver Kill Basin, Catskill Mountains, New York, 1915-94

USGS Publications Warehouse

Baldigo, Barry P.

1999-01-01

The increases in peak stormflows in the lower Beaver Kill basin through the period of record may have increased the rates of bed-sediment erosion (degradation) and deposition and accelerated changes in stream-channel morphology, however, these possible effects were not examined. Suggestions for further investigation of the effects of NY 17 and of other factors on hydrology, channel morphology, fish habitat, and fish populations in the Beaver Kill Basin include (1) addition of streamflow gages or a creststage gage network at critical locations, (2) a review of engineering records and other aerial photographs for indications of changes in channel morphology, (3) compilation of temperature data and modeling spatial extent and magnitude of stressful summer temperatures (to selected trout species), and (4) confirming the extent and severity of toxic thermal episodes using in-situ fish toxicity tests.

Protection of Levees against Beavers

NASA Astrophysics Data System (ADS)

Kozłowski, Wojciech; Balawejder, Adam

2017-10-01

Beavers are a protected species, so the levees must be properly protected so as not to harm the beavers and protect the levees from the destruction caused by these animals. This protection requires the use of bentonite mats as shaft seals, and wire mesh. Recently, such new protection structures began to be used successfully.

75 FR 77826 - White River National Forest; Eagle County, CO; Beaver Creek Mountain Improvements

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-14

... and/or affected individuals, organizations and governmental agencies will be used to identify resource... upcoming 2015 World Alpine Championships. In order for Beaver Creek to continue to host international... located at Beaver Creek. Hosting the 2015 International Skiing Federation (FIS) World Alpine Ski...

76 FR 31237 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Determination of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-31

...-Beaver Valley 8-Hour Ozone Nonattainment Area AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: EPA is making a final determination that the Pittsburgh-Beaver Valley 8-hour ozone..., Beaver, Butler, Fayette, Washington, and Westmoreland Counties in Pennsylvania. EPA's determination is...

33 CFR 117.705 - Beaver Dam Creek.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Beaver Dam Creek. 117.705 Section 117.705 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.705 Beaver Dam Creek. The draw of the...

33 CFR 117.705 - Beaver Dam Creek.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Beaver Dam Creek. 117.705 Section 117.705 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.705 Beaver Dam Creek. The draw of the...

The role of beaver in shaping steelhead trout (Oncorhynchus mykiss) habitat complexity and thermal refugia in a central Oregon stream

NASA Astrophysics Data System (ADS)

Consolati, F.; Wheaton, J. M.; Neilson, B. T.; Bouwes, N.; Pollock, M. M.

2012-12-01

The incised and degraded habitat of Bridge Creek, tributary to the John Day River in central Oregon, is thought to be limiting the local population of ESA-listed steelhead trout (Oncorhynchus mykiss). Restoration efforts for this watershed are aimed to improve their habitat through reconnecting the channel with portions of its former floodplain (now terraces) to increase stream habitat complexity and the extent of riparian vegetation. This is being done via the installation of over a hundred beaver dam support (BDS) structures that are designed to either mimic beaver dams or support existing beaver dams. The overall objective of this study is to determine if the BDS structures have had an effect on stream channel habitat complexity and thermal refugia in selected sections of Bridge Creek. Analysis of stream temperature data in restoration treatment and control areas will show the effects of beaver dams on stream temperature. Analysis of aerial imagery and high resolution topographic data will exhibit how the number and types of geomorphic units have changed after the construction of beaver dams. Combined, the results of this research are aimed to increase our understanding of how beaver dams impact fish habitat and stream temperature.

Managed flood effects on beaver pond habitat in a desert riverine ecosystem, bill williams river, Arizona USA

USGS Publications Warehouse

Andersen, D.C.; Shafroth, P.B.; Pritekel, C.M.; O'Neill, M. W.

2011-01-01

The ecological effects of beaver in warm-desert streams are poorly documented, but potentially significant. For example, stream water and sediment budgets may be affected by increased evaporative losses and sediment retention in beaver ponds. We measured physical attributes of beaver pond and adjacent lotic habitats on a regulated Sonoran Desert stream, the Bill Williams River, after ???11 flood-free months in Spring 2007 and Spring 2008. Neither a predicted warming of surface water as it passed through a pond nor a reduction in dissolved oxygen in ponds was consistently observed, but bed sediment sorted to finest in ponds as expected. We observed a river segment-scale downstream rise in daily minimum stream temperature that may have been influenced by the series of ??100 beaver ponds present. Channel cross-sections surveyed before and after an experimental flood (peak flow 65 m3/s) showed net aggradation on nine of 13 cross-sections through ponds and three of seven through lotic reaches. Our results indicate that beaver affect riverine processes in warm deserts much as they do in other biomes. However, effects may be magnified in deserts through the potential for beaver to alter the stream thermal regime and water budget. ?? Society of Wetland Scientists 2011.

Geochemistry of stream-sediment samples from the Santa Renia Fields and Beaver Peak quadrangles, northern Carlin Trend, Nevada

USGS Publications Warehouse

Theodore, Ted G.; Kotlyar, Boris B.; Berger, Vladimir I.; Moring, Barry C.; Singer, Donald A.; Edstrom, Sven A.

1999-01-01

A broad west-to-east increase of many metal concentrations has been found in stream sediments during a reconnaissance investigation conducted in conjunction with geologic studies in the Santa Renia Fields and Beaver Peak 7–1/2 minute quadrangles near the northern end of the Carlin trend of gold deposits in the Tuscarora Mountains. This regional increase in metal concentrations coincides with a dramatic change in landform wherein high concentrations of metals in stream sediments appear to correlate directly with areas of high elevations and steep slopes in the Beaver Peak quadrangle. Robust erosion combined with high flow rates in streams from these higher elevations are envisaged to have contributed significantly to increased metal concentrations in the stream sediments by an enhanced presence of minerals with high specific gravities and a correspondingly diminished presence of minerals with low specific gravities. Minerals with low specific gravities probably have been preferentially flushed down stream because of high transporting capacities for sediment by streams in the Beaver Peak quadrangle. In addition, the Carlin trend, a generally northwest-alignment of gold deposits in the Santa Renia Fields quadrangle, is well outlined by arsenic concentrations that include a maximum of approximately 54 parts per million. Further, a weakly developed distal-to-proximal metal zonation towards these gold deposits appears to be defined respectively in plots showing distributions of thallium, arsenic, antimony, and zinc. A broad area of high metal concentrations—including sharply elevated abundances of Ag, As, Au, Cd, Co, Cu, Mn, Ni, P, Sb, Sc, Te, V, and especially Zn—near the southeast corner of the Beaver Peak quadrangle primarily could be the result of stratiform mineralized rocks in the Ordovician Vinini Formation or Devonian Slaven Chert, or the result of a subsequent Mesozoic or Tertiary epigenetic overprint.

Streamflow and Water-Quality Characteristics for Wind Cave National Park, South Dakota, 2002-03

USGS Publications Warehouse

Heakin, Allen J.

2004-01-01

A 2-year study of streamflow and water-quality characteristics in Wind Cave National Park was performed by the U.S. Geological Survey in cooperation with the National Park Service. During this study, streamflow and water-quality data were collected for three of the park's perennial streams (Cold Spring, Beaver, and Highland Creeks) from January 2002 through November 2003. The potential influence of parking lot runoff on cave drip within Wind Cave also was investigated by collecting and analyzing several time-dependent samples from a drainage culvert downstream from the parking lot and from Upper Minnehaha Falls inside the cave following a series of simulated runoff events. The primary focus of the report is on data collected during the 2-year study from January 2002 to November 2003; however, data collected previously also are summarized. Losing reaches occur on both Beaver and Highland Creeks as these streams flow across outcrops of bedrock aquifers within the park. No streamflow losses occur along Cold Spring Creek because its confluence with Beaver Creek is located upstream from the outcrop of the Madison aquifer, where most streamflow losses occur. Physical properties, major ions, trace elements, nutrients, bacteria, benthic macroinvertebrates, organic (wastewater) compounds, bottom sediment, and suspended sediment are summarized for samples collected from 2 sites on Cold Spring Creek, 2 sites on Beaver Creek, and 1 site on Highland Creek. None of the constituent concentrations for any of the samples collected during 2002-03 exceeded any of the U.S. Environmental Protection Agency drinking-water standards, with the exception of the Secondary Maximum Contaminant Level for pH, which was exceeded in numerous samples from Beaver Creek and Highland Creek. Additionally, the pH values in several of these same samples also exceeded beneficial-use criteria for coldwater permanent fisheries and coldwater marginal fisheries. Water temperature exceeded the coldwater permanent fisheries criterion in numerous samples from all three streams. Two samples from Highland Creek also exceeded the coldwater marginal fisheries criterion for water temperature. Mean concentrations of ammonia, orthophosphate, and phosphorous were higher for the upstream site on Beaver Creek than for other water-quality sampling sites. Concentrations of E. coli, fecal coliform, and total coliform bacteria also were higher at the upstream site on Beaver Creek than for any other site. Samples for the analysis of benthic macroinvertebrates were collected from one site on each of the three streams during July 2002 and May 2003. The benthic macroinvertebrate data showed that Beaver Creek had lower species diversity and a higher percentage of tolerant species than the other two streams during 2002, but just the opposite was found during 2003. However, examination of the complete data set indicates that the quality of water at the upstream site was generally poorer than the quality of water at the downstream site. Furthermore, the quality of water at the upstream site on Beaver Creek is somewhat degraded when compared to the quality of water from Highland and Cold Spring Creeks, indicating that anthropogenic activities outside the park probably are affecting the quality of water in Beaver Creek. Samples for the analysis of wastewater compounds were collected at least twice from four of the five water-quality sampling sites. Bromoform, phenol, caffeine, and cholesterol were detected in samples from Cold Spring Creek, but only phenol was detected at concentrations greater than the minimum reporting level. Concentrations of several wastewater compounds were estimated in samples collected from sites on Beaver Creek, including phenol, para-cresol, and para-nonylphenol-total. Phenol was detected at both sites on Beaver Creek at concentrations greater than the minimum reporting level. Bromoform; para-cresol; ethanol,2-butoxy-phosphate; and cholesterol were detected

Beaver Ponds: Resurgent Nitrogen Sinks for Rural Watersheds in the Northeastern United States.

PubMed

Lazar, Julia G; Addy, Kelly; Gold, Arthur J; Groffman, Peter M; McKinney, Richard A; Kellogg, Dorothy Q

2015-09-01

Beaver-created ponds and dams, on the rise in the northeastern United States, reshape headwater stream networks from extensive, free-flowing reaches to complexes of ponds, wetlands, and connecting streams. We examined seasonal and annual rates of nitrate transformations in three beaver ponds in Rhode Island under enriched nitrate-nitrogen (N) conditions through the use of N mass balance techniques on soil core mesocosm incubations. We recovered approximately 93% of the nitrate N from our mesocosm incubations. Of the added nitrate N, 22 to 39% was transformed during the course of the incubation. Denitrification had the highest rates of transformation (97-236 mg N m d), followed by assimilation into the organic soil N pool (41-93 mg N m d) and ammonium generation (11-14 mg N m d). Our denitrification rates exceeded those in several studies of freshwater ponds and wetlands; however, rates in those ecosystems may have been limited by low concentrations of nitrate. Assuming a density of 0.7 beaver ponds km of catchment area, we estimated that in nitrate-enriched watersheds, beaver pond denitrification can remove approximately 50 to 450 kg nitrate N km catchment area. In rural watersheds of southern New England with high N loading (i.e., 1000 kg km), denitrification from beaver ponds may remove 5 to 45% of watershed nitrate N loading. Beaver ponds represent a relatively new and substantial sink for watershed N if current beaver populations persist. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Modeling Potential Surface and Shallow Groundwater Storage Provided by Beaver Ponds Across Watersheds

NASA Astrophysics Data System (ADS)

Hafen, K.; Wheaton, J. M.; Macfarlane, W.

2016-12-01

Damming of streams by North American Beaver (Castor canadensis) has been shown to provide a host of potentially desirable hydraulic and hydrologic impacts. Notably, increases in surface water storage and groundwater storage may alter the timing and delivery of water around individual dams and dam complexes. Anecdotal evidence suggests these changes may be important for increasing and maintaining baseflow and even helping some intermittent streams flow perennially. In the arid west, these impacts could be particularly salient in the face of climate change. However, few studies have examined the hydrologic impacts of beaver dams at scales large enough to provide insight for water management, in part because understanding or modeling these impacts at large spatial scales has been precluded by uncertainty concerning the number of beaver dams a drainage network can support. Using the recently developed Beaver Restoration Assessment Tool (BRAT) to identify possible densities and spatial configurations of beaver dams, we developed a model that predicts the area and volume of surface water storage associated with dams of various sizes, and applied this model at different dam densities across multiple watersheds (HUC12) in northern Utah. We then used model results as inputs to the MODFLOW groundwater model to identify the subsequent changes to shallow groundwater storage. The spatially explicit water storage estimates produced by our approach will be useful in evaluating potential beaver restoration and conservation, and will also provide necessary information for developing hydrologic models to specifically identify the effects beaver dams may have on water delivery and timing.

River restoration strategies in channelized, low-gradient landscapes of West Tennessee, USA

USGS Publications Warehouse

Smith, D.P.; Diehl, T.H.; Turrini-Smith, L. A.; Maas-Baldwin, J.; Croyle, Z.

2009-01-01

West Tennessee has a complex history of watershed disturbance, including agricultural erosion, channelization, accelerated valley sedimentation, and the removal and reestablishment of beaver. Watershed management has evolved from fl oodplain drainage via pervasive channelization to include local drainage canal maintenance and local river restoration. Many unmaintained canals are undergoing excessive aggradation and complex channel evolution driven by upland erosion and low valley gradient. The locus of aggradation in fully occluded canals (valley plugs) moves up-valley as sediment continues to accumulate in the backwater behind the plug. Valley plugs that cause canal avulsion can lead to redevelopment of meandering channels in less disturbed areas of the fl oodplain, in a process of passive self-restoration. Some valley plugs have brought restored fl oodplain function, reoccupation of extant historic river channels, and formation of a "sediment shadow" that protects downstream reaches from excess sedimentation. Despite the presence of numerous opportunities, there is presently no mechanism for including valley plugs in mitigation projects. In 1997 a survey of 14 reference reach cross sections documented relations between drainage area and bankfull geometry of relatively unmodified streams in West Tennessee. Reassessment of seven of those sites in 2007 showed that one had been dammed by beaver and that two sites could not be analyzed further because of signifi cant vertical or lateral instability. In contrast to other regions of North America, the results suggest that stream channels in this region fl ood more frequently than once each year, and can remain out of banks for several weeks each year. ?? 2009 Geological Society of America.

Geotagging Digital Collections: BeaverTracks Mobile Project

ERIC Educational Resources Information Center

Griggs, Kim

2011-01-01

BeaverTracks Historical Locations and Walking Tour is a mobile project at Oregon State University (OSU), where the author serves as programmer/analyst. It connects the past to the present by linking historic images to current campus locations. The goal of BeaverTracks is to showcase and bring attention to OSU Libraries' digital collections as well…

Survey of beaver-related restoration practices in rangeland streams of the western USA

Treesearch

David S. Pilliod; Ashley T. Rohde; Susan Charnley; Rachael R. Davee; Jason B. Dunham; Hannah Gosnell; Gordon E. Grant; Mark B. Hausner; Justin L. Huntington; Caroline Nash

2018-01-01

Poor condition of many streams and concerns about future droughts in the arid and semi-arid western USA have motivated novel restoration strategies aimed at accelerating recovery and increasing water resources. Translocation of beavers into formerly occupied habitats, restoration activities encouraging beaver recolonization, and instream structures mimicking the...

CARBON TRACE GASES IN LAKE AND BEAVER POND ICE NEAR THOMPSON, MANITOBA, CANADA

EPA Science Inventory

Concentrations of CO2, CO, and CH4 were measured in beaver pond and lake ice in April 1996 near Thompson, Manitoba to derive information on possible impacts of ice melting on corresponding atmospheric trace gas concentrations. CH4 concentrations in beaver pond and lake ice ranged...

Using structural equation modeling to link human activities to wetland ecological integrity

USGS Publications Warehouse

Schweiger, E. William; Grace, James B.; Cooper, David; Bobowski, Ben; Britten, Mike

2016-01-01

The integrity of wetlands is of global concern. A common approach to evaluating ecological integrity involves bioassessment procedures that quantify the degree to which communities deviate from historical norms. While helpful, bioassessment provides little information about how altered conditions connect to community response. More detailed information is needed for conservation and restoration. We have illustrated an approach to addressing this challenge using structural equation modeling (SEM) and long-term monitoring data from Rocky Mountain National Park (RMNP). Wetlands in RMNP are threatened by a complex history of anthropogenic disturbance including direct alteration of hydrologic regimes; elimination of elk, wolves, and grizzly bears; reintroduction of elk (absent their primary predators); and the extirpation of beaver. More recently, nonnative moose were introduced to the region and have expanded into the park. Bioassessment suggests that up to half of the park's wetlands are not in reference condition. We developed and evaluated a general hypothesis about how human alterations influence wetland integrity and then develop a specific model using RMNP wetlands. Bioassessment revealed three bioindicators that appear to be highly sensitive to human disturbance (HD): (1) conservatism, (2) degree of invasion, and (3) cover of native forbs. SEM analyses suggest several ways human activities have impacted wetland integrity and the landscape of RMNP. First, degradation is highest where the combined effects of all types of direct HD have been the greatest (i.e., there is a general, overall effect). Second, specific HDs appear to create a “mixed-bag” of complex indirect effects, including reduced invasion and increased conservatism, but also reduced native forb cover. Some of these effects are associated with alterations to hydrologic regimes, while others are associated with altered shrub production. Third, landscape features created by historical beaver activity continue to influence wetland integrity years after beavers have abandoned sites via persistent landforms and reduced biomass of tall shrubs. Our model provides a system-level perspective on wetland integrity and provides a context for future evaluations and investigations. It also suggests scientifically supported natural resource management strategies that can assist in the National Park Service mission of maintaining or, when indicated, restoring ecological integrity “unimpaired for future generations.”

Eurasian beaver activity increases water storage, attenuates flow and mitigates diffuse pollution from intensively-managed grasslands.

PubMed

Puttock, Alan; Graham, Hugh A; Cunliffe, Andrew M; Elliott, Mark; Brazier, Richard E

2017-01-15

Beavers are the archetypal keystone species, which can profoundly alter ecosystem structure and function through their ecosystem engineering activity, most notably the building of dams. This can have a major impact upon water resource management, flow regimes and water quality. Previous research has predominantly focused on the activities of North American beaver (Castor canadensis) located in very different environments, to the intensive lowland agricultural landscapes of the United Kingdom and elsewhere in Europe. Two Eurasian beavers (Castor fiber) were introduced to a wooded site, situated on a first order tributary, draining from intensively managed grassland. The site was monitored to understand impacts upon water storage, flow regimes and water quality. Results indicated that beaver activity, primarily via the creation of 13 dams, has increased water storage within the site (holding ca. 1000m 3 in beaver ponds) and beavers were likely to have had a significant flow attenuation impact, as determined from peak discharges (mean 30±19% reduction), total discharges (mean 34±9% reduction) and peak rainfall to peak discharge lag times (mean 29±21% increase) during storm events. Event monitoring of water entering and leaving the site showed lower concentrations of suspended sediment, nitrogen and phosphate leaving the site (e.g. for suspended sediment; average entering site: 112±72mgl -1 , average leaving site: 39±37mgl -1 ). Combined with attenuated flows, this resulted in lower diffuse pollutant loads in water downstream. Conversely, dissolved organic carbon concentrations and loads downstream were higher. These observed changes are argued to be directly attributable to beaver activity at the site which has created a diverse wetland environment, reducing downstream hydrological connectivity. Results have important implications for beaver reintroduction programs which may provide nature based solutions to the catchment-scale water resource management issues that are faced in agricultural landscapes. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Mitochondrial Genomes Reveal Slow Rates of Molecular Evolution and the Timing of Speciation in Beavers (Castor), One of the Largest Rodent Species

PubMed Central

Horn, Susanne; Durka, Walter; Wolf, Ronny; Ermala, Aslak; Stubbe, Annegret; Stubbe, Michael; Hofreiter, Michael

2011-01-01

Background Beavers are one of the largest and ecologically most distinct rodent species. Little is known about their evolution and even their closest phylogenetic relatives have not yet been identified with certainty. Similarly, little is known about the timing of divergence events within the genus Castor. Methodology/Principal Findings We sequenced complete mitochondrial genomes from both extant beaver species and used these sequences to place beavers in the phylogenetic tree of rodents and date their divergence from other rodents as well as the divergence events within the genus Castor. Our analyses support the phylogenetic position of beavers as a sister lineage to the scaly tailed squirrel Anomalurus within the mouse related clade. Molecular dating places the divergence time of the lineages leading to beavers and Anomalurus as early as around 54 million years ago (mya). The living beaver species, Castor canadensis from North America and Castor fiber from Eurasia, although similar in appearance, appear to have diverged from a common ancestor more than seven mya. This result is consistent with the hypothesis that a migration of Castor from Eurasia to North America as early as 7.5 mya could have initiated their speciation. We date the common ancestor of the extant Eurasian beaver relict populations to around 210,000 years ago, much earlier than previously thought. Finally, the substitution rate of Castor mitochondrial DNA is considerably lower than that of other rodents. We found evidence that this is correlated with the longer life span of beavers compared to other rodents. Conclusions/Significance A phylogenetic analysis of mitochondrial genome sequences suggests a sister-group relationship between Castor and Anomalurus, and allows molecular dating of species divergence in congruence with paleontological data. The implementation of a relaxed molecular clock enabled us to estimate mitochondrial substitution rates and to evaluate the effect of life history traits on it. PMID:21307956

Presence of Antibodies to Leptospira spp. in Black-tailed Prairie Dogs ( Cynomys ludovicianus ) and Beavers ( Castor canadensis ) in Northwestern Mexico.

PubMed

López-Pérez, Andrés M; Carreón-Arroyo, Gerardo; Atilano, Daniel; Vigueras-Galván, Ana L; Valdez, Carlos; Toyos, Daniel; Mendizabal, Daniel; López-Islas, Jonathan; Suzán, Gerardo

2017-10-01

Leptospires are widespread spirochete bacteria that infect mammals, including rodents and humans. We investigated the presence of Leptospira antibodies in two species of rodents from San Pedro River Basin (SPRB) in northwestern Mexico as part of the black-tailed prairie dog ( Cynomys ludovicianus ) monitoring plan and the North American beaver ( Castor canadensis ) reintroduction program. We sampled a total of 26 black-tailed prairie dogs and three beavers during October-November 2015. We detected antibodies against Leptospira spp. by microagglutination test in 12 (46%) prairie dogs and in two (67%) beavers. The antibody titers for seropositive rodents varied from 1:100 to 1:200, but none of the animals showed clinical signs of disease. We found seven Leptospira spp. serogroups (Autumnalis, Australis, Bataviae, Canicola, Celledoni, Grippotyphosa, and Sejroe) circulating in rodent species in SPRB. We did not find any differences between sex and age concerning Leptospira-positive rodents. Our findings suggest the presence of endemic cycles and potential risks of Leptospira infection in both species from SPRB. Although the impact of this infection on threatened species remains unclear, human activities and environmental stress might facilitate the emergence or reemergence of leptospirosis disease as has been reported elsewhere.

Planetary micro-rover operations on Mars using a Bayesian framework for inference and control

NASA Astrophysics Data System (ADS)

Post, Mark A.; Li, Junquan; Quine, Brendan M.

2016-03-01

With the recent progress toward the application of commercially-available hardware to small-scale space missions, it is now becoming feasible for groups of small, efficient robots based on low-power embedded hardware to perform simple tasks on other planets in the place of large-scale, heavy and expensive robots. In this paper, we describe design and programming of the Beaver micro-rover developed for Northern Light, a Canadian initiative to send a small lander and rover to Mars to study the Martian surface and subsurface. For a small, hardware-limited rover to handle an uncertain and mostly unknown environment without constant management by human operators, we use a Bayesian network of discrete random variables as an abstraction of expert knowledge about the rover and its environment, and inference operations for control. A framework for efficient construction and inference into a Bayesian network using only the C language and fixed-point mathematics on embedded hardware has been developed for the Beaver to make intelligent decisions with minimal sensor data. We study the performance of the Beaver as it probabilistically maps a simple outdoor environment with sensor models that include uncertainty. Results indicate that the Beaver and other small and simple robotic platforms can make use of a Bayesian network to make intelligent decisions in uncertain planetary environments.

Identifying source populations for the reintroduction of the Eurasian beaver, Castor fiber L. 1758, into Britain: evidence from ancient DNA.

PubMed

Marr, Melissa M; Brace, Selina; Schreve, Danielle C; Barnes, Ian

2018-02-09

Establishing true phylogenetic relationships between populations is a critical consideration when sourcing individuals for translocation. This presents huge difficulties with threatened and endangered species that have become extirpated from large areas of their former range. We utilise ancient DNA (aDNA) to reconstruct the phylogenetic relationships of a keystone species which has become extinct in Britain, the Eurasian beaver Castor fiber. We sequenced seventeen 492 bp partial tRNAPro and control region sequences from Late Pleistocene and Holocene age beavers and included these in network, demographic and genealogy analyses. The mode of postglacial population expansion from refugia was investigated by employing tests of neutrality and a pairwise mismatch distribution analysis. We found evidence of a pre-Late Glacial Maximum ancestor for the Western C. fiber clade which experienced a rapid demographic expansion during the terminal Pleistocene to early Holocene period. Ancient British beavers were found to originate from the Western phylogroup but showed no phylogenetic affinity to any one modern relict population over another. Instead, we find that they formed part of a large, continuous, pan-Western European clade that harbored little internal substructure. Our study highlights the utility of aDNA in reconstructing population histories of extirpated species which has real-world implications for conservation planning.

Genetic methods improve accuracy of gender determination in beaver

USGS Publications Warehouse

Williams, C.L.; Breck, S.W.; Baker, B.W.

2004-01-01

Gender identification of sexually monomorphic mammals can be difficult. We used analysis of zinc-finger protein (Zfx and Zfy) DNA regions to determine gender of 96 beavers (Castor canadensis) from 3 areas and used these results to verify gender determined in the field. Gender was correctly determined for 86 (89.6%) beavers. Incorrect assignments were not attributed to errors in any one age or sex class. Although methods that can be used in the field (such as morphological methods) can provide reasonably accurate gender assignments in beavers, the genetic method might be preferred in certain situations.

Modeling the capacity of riverscapes to support beaver dams

NASA Astrophysics Data System (ADS)

Macfarlane, William W.; Wheaton, Joseph M.; Bouwes, Nicolaas; Jensen, Martha L.; Gilbert, Jordan T.; Hough-Snee, Nate; Shivik, John A.

2017-01-01

The construction of beaver dams facilitates a suite of hydrologic, hydraulic, geomorphic, and ecological feedbacks that increase stream complexity and channel-floodplain connectivity that benefit aquatic and terrestrial biota. Depending on where beaver build dams within a drainage network, they impact lateral and longitudinal connectivity by introducing roughness elements that fundamentally change the timing, delivery, and storage of water, sediment, nutrients, and organic matter. While the local effects of beaver dams on streams are well understood, broader coverage network models that predict where beaver dams can be built and highlight their impacts on connectivity across diverse drainage networks are lacking. Here we present a capacity model to assess the limits of riverscapes to support dam-building activities by beaver across physiographically diverse landscapes. We estimated dam capacity with freely and nationally-available inputs to evaluate seven lines of evidence: (1) reliable water source, (2) riparian vegetation conducive to foraging and dam building, (3) vegetation within 100 m of edge of stream to support expansion of dam complexes and maintain large colonies, (4) likelihood that channel-spanning dams could be built during low flows, (5) the likelihood that a beaver dam is likely to withstand typical floods, (6) a suitable stream gradient that is neither too low to limit dam density nor too high to preclude the building or persistence of dams, and (7) a suitable river that is not too large to restrict dam building or persistence. Fuzzy inference systems were used to combine these controlling factors in a framework that explicitly also accounts for model uncertainty. The model was run for 40,561 km of streams in Utah, USA, and portions of surrounding states, predicting an overall network capacity of 356,294 dams at an average capacity of 8.8 dams/km. We validated model performance using 2852 observed dams across 1947 km of streams. The model showed excellent agreement with observed dam densities where beaver dams were present. Model performance was spatially coherent and logical, with electivity indices that effectively segregated capacity categories. That is, beaver dams were not found where the model predicted no dams could be supported, beaver avoided segments that were predicted to support rare or occasional densities, and beaver preferentially occupied and built dams in areas predicted to have pervasive dam densities. The resulting spatially explicit reach-scale (250 m long reaches) data identifies where dam-building activity is sustainable, and at what densities dams can occur across a landscape. As such, model outputs can be used to determine where channel-floodplain and wetland connectivity are likely to persist or expand by promoting increases in beaver dam densities.

Beaver dams, hydrological thresholds, and controlled floods as a management tool in a desert riverine ecosystem, Bill Williams River, Arizona

USGS Publications Warehouse

Andersen, D.C.; Shafroth, P.B.

2010-01-01

Beaver convert lotic stream habitat to lentic through dam construction, and the process is reversed when a flood or other event causes dam failure. We investigated both processes on a regulated Sonoran Desert stream, using the criterion that average current velocity is < 0.2 m s-1 in a lentic reach. We estimated temporal change in the lotic:lentic stream length ratio by relating beaver pond length (determined by the upstream lentic-lotic boundary position) to dam size, and coupling that to the dam-size frequency distribution and repeated censuses of dams along the 58-km river. The ratio fell from 19:1 when no beaver dams were present to < 3:1 after 7 years of flows favourable for beaver. We investigated the dam failure-flood intensity relationship in three independent trials (experimental floods) featuring peak discharge ranging from 37 to 65 m3 s-1. Major damage (breach ??? 3-m wide) occurred at ??? 20% of monitored dams (n = 7-86) and a similar or higher proportion was moderately damaged. We detected neither a relationship between dam size and damage level nor a flood discharge threshold for initiating major damage. Dam constituent materials appeared to control the probability of major damage at low (attenuated) flood magnitude. We conclude that environmental flows prescribed to sustain desert riparian forest will also reduce beaver-created lentic habitat in a non-linear manner determined by both beaver dam and flood attributes. Consideration of both desirable and undesirable consequences of ecological engineering by beaver is important when optimizing environmental flows to meet ecological and socioeconomic goals. ?? 2010 John Wiley & Sons, Ltd.

The Beaver Creek story

USGS Publications Warehouse

Doyle, W.H.; Whitworth, B.G.; Smith, G.F.; Byl, T.D.

1996-01-01

Beaver Creek watershed in West Tennessee includes about 95,000 acres of the Nation's most productive farmland and most highly erodible soils. In 1989 the U.S. Geological Survey, in cooperation with the Tennessee Department of Agriculture, began a study to evaluate the effect of agricultural activities on water quality in the watershed and for best management practices designed to reduce agricultural nonpoint-source pollution. Agrichemical monitoring included testing the soils, ground water, and streams at four farm sites ranging from 27 to 420 acres. Monitoring stations were operated downstream to gain a better understanding of the water chemistry as runoff moved from small ditches into larger streams to the outlet of the Beaver Creek watershed. Prior to the implementation of best management practices at one of the farm study sites, some storms produced an average suspended-sediment concentration of 70,000 milligrams per liter. After the implementation of BMP's, however, the average value never exceeded 7,000 milligrams per liter. No-till crop production was the most effective best management practice for conserving soil on the farm fields tested. A natural bottomland hardwood wetland and a constructed wetland were evaluated as instream resource-management systems. The wetlands improved water quality downstream by acting as a filter and removing a significant amount of nonpoint-source pollution from the agricultural runoff. The constructed wetland reduced the sediment, pesticide, and nutrient load by approximately 50 percent over a 4-month period. The results of the Beaver Creek watershed study have increased the understanding of the effects of agriculture on water resources. Study results also demonstrated that BMP's do protect and improve water quality.

The Eurasian beaver (Castor fiber) is apparently not a host to blood parasites in Norway.

PubMed

Cross, Hannah B; Campbell-Palmer, Róisín; Girling, Simon; Rosell, Frank

2012-11-23

Parasites can alter the physiology and behaviour of host species and negatively impact on their fitness thus affecting population densities. This is the first investigation into the presence of blood parasites in the Eurasian beaver (Castor fiber); a species that has been the subject of many translocation and reintroduction programmes. Two hundred and seventy blood slides prepared from the blood of 27 beavers from southern Norway were microscopically analysed for the presence of blood parasites. This study reports an absence of blood parasites in the Norwegian Eurasian beavers sampled. Copyright © 2012 Elsevier B.V. All rights reserved.

Impacts of beaver ponds on dissolved organic matter cycling in small temperate streams.

NASA Astrophysics Data System (ADS)

Larsen, J.; Lambert, T.; Larsen, A.; Lane, S.

2017-12-01

Beavers are engineers that modify the structure of river reaches and their hydrological functioning. By building dams, they modify the travel time of running waters and can lead to the flooding of surrounding soils and terrestrial vegetation, with potentially significant impact on biogeochemical cycles. Contradictory effects of beaver ponds on dissolved organic matter (DOM) concentration and composition have however been reported, and the underlying reasons are still unclear. In this study, we aimed to investigate the role of the landscape morphology as an important driver determining how a beaver population can affect stream DOM cycling. Four streams localized in Switzerland and Germany were visited during different seasons (spring, summer, winter) and monitored at upstream and downstream locations of beaver ponds across a hydrological cycle. The sites differed in terms of river channel morphology, presence or absence of floodplain, and vegetation cover. DOM composition was investigated through absorbance and fluorescence measurements coupled with parallel factor analysis (PARAFAC) along with stream water quality (nutrients, pH, dissolved oxygen and water temperature). The results show that the effects of beaver dams were variable, and emphasizes the importance of the geomorphological context.

The Use of Acceleration to Code for Animal Behaviours; A Case Study in Free-Ranging Eurasian Beavers Castor fiber

PubMed Central

Graf, Patricia M.; Wilson, Rory P.; Qasem, Lama; Hackländer, Klaus; Rosell, Frank

2015-01-01

Recent technological innovations have led to the development of miniature, accelerometer-containing electronic loggers which can be attached to free-living animals. Accelerometers provide information on both body posture and dynamism which can be used as descriptors to define behaviour. We deployed tri-axial accelerometer loggers on 12 free-ranging Eurasian beavers Castor fiber in the county of Telemark, Norway, and on four captive beavers (two Eurasian beavers and two North American beavers C. canadensis) to corroborate acceleration signals with observed behaviours. By using random forests for classifying behavioural patterns of beavers from accelerometry data, we were able to distinguish seven behaviours; standing, walking, swimming, feeding, grooming, diving and sleeping. We show how to apply the use of acceleration to determine behaviour, and emphasise the ease with which this non-invasive method can be implemented. Furthermore, we discuss the strengths and weaknesses of this, and the implementation of accelerometry on animals, illustrating limitations, suggestions and solutions. Ultimately, this approach may also serve as a template facilitating studies on other animals with similar locomotor modes and deliver new insights into hitherto unknown aspects of behavioural ecology. PMID:26317623

Histological Evaluation of Selected Organs of the Eurasian Beavers (Castor fiber) Inhabiting Poland.

PubMed

Dolka, I; Giżejewska, A; Giżejewski, Z; Kluciński, W; Kołodziejska, J

2015-10-01

There is a general scarcity of data on the histological structure of major organs in the Eurasian beaver (Castor fiber). This study presents the histological characteristics of beaver organs such as the liver, spleen, cardiac muscle, lungs and kidneys. Tissue samples were collected from 21 beavers and analysed. Selected samples of tail tissue were additionally examined. Tissue samples were placed in neutral buffered formalin and embedded in paraffin. 4-μm-thick sections were stained with haematoxylin and eosin, and other staining techniques were also used. Scant amounts of inter-lobular connective tissue were found in the liver. Ion or copper deposition was not observed, but scattered cytoplasmic glycogen deposits were present in hepatocytes. Our results suggest that beavers have defensive rather than storage spleens. Interestingly, the presence of melanin in splenic red pulp was noted. The histological structure of the examined organs closely resembled that of other rodent species. According to our knowledge, this is the first study evaluating the histological structure of beaver organs. Nevertheless, precise characterization of the evaluated organs requires further work with the involvement of accurate and reliable techniques, such as molecular biology or electron microscopy methods. © 2014 Blackwell Verlag GmbH.

Surface water of Beaver Creek Basin, in South-Central Oklahoma

USGS Publications Warehouse

Laine, L.L.; Murphy, J.J.

1962-01-01

Annual discharge from Beaver Creek basin is estimated to have averaged 217,000 acre-feet during a 19-year base period, water years 1938-56, equivalent to an average annual runoff depth of 4.7 inches over the 857 square-mile drainage area. About 55,000 acre-feet per year comes from Little Beaver Creek basin, a tributary drainage of 195 square miles. Yearly streamflow is highly variable. The discharge of Little Beaver Creek near Duncan during 13-year period of record (water years 1949-61) has ranged from 86,530 acre-feet in calendar year 1957 to 4,880 acre-feet in 1956, a ratio of almost 18 to 1. Highest runoff within a year tends to occur in the spring months of May and June, a 2-month period that, on the average, accounts for more than half of the annual discharge of Little Beaver Creek near Duncan. The average monthly runoff during record was lowest in January. Variation in daily streamflow is such that while the average discharge for the 13-year period of record was 50.1 cfs (cubic feet per second), the daily discharge was more than 6 cfs only about half of the time. There was no flow at the site 19 percent of the time during the period. Some base runoff usually exists in the headwaters of Beaver and Little Beaver Creeks, and in the lower reaches of Beaver Creek. Low flow in Cow Creek tends to be sustained by waste water from Duncan, where water use in 1961 averaged 4 million gallons per day. In the remainder of the basin, periods of no flow occur in most years. The surface water of Beaver Creek basin is very hard but in general is usable for municipal, agricultural and industrial purposes. The chemical character of the water is predominantly a calcium, magnesium bicarbonate type of water in the lower three quarters of the basin, except in Cow Creek where oil-field brines induce a distinct sodium, calcium chloride characteristic at low and medium flows. A calcium sulfate type of water occurs in most of the northern part of the basin except in headwater areas underlain by the Rush Springs Sandstone, where quality is similar to that in the lower basin. The report gives an estimate of the average discharge at several sites in Beaver Creek basin for a 19-year base period, October 1937 to September 1956. Duration curves of daily discharge for Little Beaver Creek near Duncan and Beaver Creek near Waurika are shown for the period of record. Monthly and annual discharge records for these gaging stations are presented. The results of 52 discharge measurements at 17 other sites in the basin are tabulated, with 5 groups being plotted as discharge profiles. Storage requirements for regulated discharge at the two gaging stations are shown. (available as photostat copy only)

Evaluating the Role of Small Impoundments in Legacy Sediment Storage

NASA Astrophysics Data System (ADS)

Bain, D. J.; Salant, N.; Green, M. B.; Wreschnig, A. J.; Urbanova, T.

2009-12-01

Recent research highlighting the prevalence of dams built for water power in the mid-1800s has led to suggestions that strategies for managing legacy sediment in the Eastern United States should be re-evaluated. However, the link between reach-scale observations of historic dam sites to processes at the catchment scale have not been examined, nor have the role of other, similar historic changes been evaluated. This presentation will compare dam dynamics, including mill density data and synthetic estimates of beaver populations with sedimentation rates recorded in sediment cores. If low-head dams were a dominant mechanism in sediment storage, we expect to see changes in sedimentation rates with the expatriation of the beaver and the rise and decline of water power. Further, we expect to see spatial variation in these changes as beaver and mill densities and potential sediment yield are spatially heterogeneous. Ultimately, dramatic changes in sediment yield due to land use and hydrological alterations likely drove sedimentation rates; the mechanistic importance of storage likely depends on temporal coincidence.

Parameterization of the ACRU model for estimating biophysical and climatological change impacts, Beaver Creek, Alberta

NASA Astrophysics Data System (ADS)

Forbes, K. A.; Kienzle, S. W.; Coburn, C. A.; Byrne, J. M.

2006-12-01

Multiple threats, including intensification of agricultural production, non-renewable resource extraction and climate change, are threatening Southern Alberta's water supply. The objective of this research is to calibrate/evaluate the Agricultural Catchments Research Unit (ACRU) agrohydrological model; with the end goal of forecasting the impacts of a changing environment on water quantity. The strength of this model is the intensive multi-layered soil water budgeting routine that integrates water movement between the surface and atmosphere. The ACRU model was parameterized using data from Environment Canada's climate database for a twenty year period (1984-2004) and was used to simulate streamflow for Beaver Creek. The simulated streamflow was compared to Environment Canada's historical streamflow database to validate the model output. The Beaver Creek Watershed, located in the Porcupine Hills southwestern Alberta, Canada contains a heterogeneous cover of deciduous, coniferous, native prairie grasslands and forage crops. In a catchment with highly diversified land cover, canopy architecture cannot be overlooked in rainfall interception parameterization. Preliminary testing of ACRU suggests that streamflows were sensitive to varied levels of leaf area index (LAI), a representative fraction of canopy foliage. Further testing using remotely sensed LAI's will provide a more accurate representation of canopy foliage and ultimately best represent this important element of the hydrological cycle and the associated processes which govern the natural hydrology of the Beaver Creek watershed.

Reconnaissance investigation of high-calcium marble in the Beaver Creek area, St. Lawrence County, New York

USGS Publications Warehouse

Brown, C. Ervin

1978-01-01

Three belts of marble of the Grenville Series were mapped in the Beaver Creek drainage basin, St. Lawrence County, N.Y. One of these, on the west side of Beaver Creek, consists of coarsely crystalline pure calcitic marble that occurs in a zone at least 10 by 0.8 km in extent. Samples of marble show CaCO3 content to be greater than 93 percent, and some samples contain greater than 96 percent, and only small amounts of MgO and Fe203 are present. Marble in two other belts to the east of Beaver Creek are variable in composition, but locally have high content of calcium carbonate material. The marble deposit west of Beaver Creek has a chemical composition favorable for specialized chemical, industrial, and metallurgical uses. Another favorable aspect of the deposit is its proximity to inexpensive water transportation on the St. Lawrence Seaway only 27.5 km away by road, at Ogdensburg, N.Y.

Responses of beaver (Castor canadensis Kuhl) to predator chemicals.

PubMed

Engelhart, A; Müller-Schwarze, D

1995-09-01

Free-ranging beaver (Castor canadensis) in two different beaver populations in New York State were exposed to predator chemicals to test feeding inhibition. Solvent extracts of feces were applied to stem sections of aspen, the preferred food tree of beavers, permitting smelling and tasting the samples. Predator odors were from wolf (Canis lupus), coyote (Canis latrans), dog (Canis familiaris), black bear (Ursus americanus), river otter (Lutra canadensis), lynx (Lynx canadensis), and African lion (Panthera leo). The experiment was repeated. The predator odors reduced feeding compared to untreated or solvent-treated controls. One population consumed 17.0% of the samples with predator odor and 27.0% of the controls in summer, and 48.4% and 60.0%, respectively, in autumn. The other population accepted 3.15% of the predator odor samples and 11.05% of the controls in summer. Coyote, lynx, and river otter odors had the strongest effects. Diesel oil and bitter-tasting neem extract had weaker effects. Predator odors are promising as feeding repellents for beaver.

Development of a reliable method for determining sex for a primitive rodent, the Point Arena mountain beaver (Aplodontia rufa nigra)

Treesearch

Kristine L. Pilgrim; William J. Zielinski; Fredrick V. Schlexer; Michael K. Schwartz

2012-01-01

The mountain beaver (Aplodontia rufa) is a primitive species of rodent, often considered a living fossil. The Point Arena mountain beaver (Aplodontia rufa nigra) is an endangered subspecies that occurs in a very restricted range in northern California. Efforts to recover this taxon have been limited by the lack of knowledge on their demography, particularly sex and age...

Channel aggradation by beaver dams on a small agricultural stream in Eastern Nebraska

Treesearch

M.C. McCullough; J.L. Harper; D.E. Eisenhauer; M.G. Dosskey

2004-01-01

We assessed the effect of beaver dams on channel gradation of an incised stream in an agricultural area of eastern Nebraska. A topographic survey was conducted of a reach of Little Muddy Creek where beaver are known to have been building dams for twelve years. Results indicating that over this time period the thalweg elevation has aggraded an average of 0.65 m by...

The impacts of Phalaris arundinacea (reed canary grass) invasion on wetland plant richness in the Oregon Coast Range, USA, depend on beavers

USGS Publications Warehouse

Perkins, T.; Wilson, M.

2005-01-01

Invasive plants can threaten diversity and ecosystem function. We examined the relationship between the invasive Phalaris arundinacea (reed canarygrass) and species richness in beaver wetlands in Oregon, USA. Four basins (drainages) were chosen and three sites each of beaver impoundments, unimpounded areas and areas upstream of debris jams were randomly chosen in each basin for further study (n = 36). Analysis of covariance (ANCOVA) showed that the relationship between Phalaris and species richness differed significantly (p = 0.01) by site type. Dam sites (beaver impoundments) exhibited a strong inverse relationship between Phalaris and species richness (bD = a??0.15), with one species lost for each 7% increase in Phalaris cover. In contrast, there was essentially no relationship between Phalaris cover and species richness in jam sites (debris jam impoundments formed by flooding; bJ = +0.01) and unimpounded sites (bU = a??0.03). The cycle of beaver impoundment and abandonment both disrupts the native community and provides an ideal environment for Phalaris, which once established tends to exclude development of herbaceous communities and limits species richness. Because beaver wetlands are a dominant wetland type in the Coast Range, Phalaris invasion presents a real threat to landscape heterogeneity and ecosystem function in the region.

Beaver lodge distributions and damage assessments in a forested wetland ecosystem in the southern United States

USGS Publications Warehouse

King, S.L.; Keeland, B.D.; Moore, J.L.

1998-01-01

Caddo Lake, USA, a Ramsar Wetland of International Importance, is a lacustrine wetland complex consisting of stands of flooded baldcypress intermixed with open water and emergent wetland habitats. Recently, concern has been expressed over a perceived increase in the beaver population and the impact of beaver on the long-term sustainability of the baldcypress ecosystem. We used intensive beaver lodge surveys to determine the distribution and relative abundance of beaver and the amount, type, and distribution of beaver damage to mature trees and seedlings at Caddo Lake. A total of 229 lodges were located with a combination of aerial and boat/ground surveys. Most lodges were located in open water and edge habitats. About 95% of the lodges were occupied by beaver or nutria. Some form of damage was exhibited by one or more trees near 85% of the lodges. Intensive damage assessments around 35 lodges indicated that most damage to trees, baldcypress in particular, was restricted to peeling or stripping of bark which is believed to have minimal effect on tree survival. Surveys of regeneration indicated that baldcypress seedlings were very abundant; however, over 99.9% were less than 30 cm tall. The lack of recruitment into the larger size classes appears to be a result of high stand densities and water management practices. At this time, the young age and density of the baldcypress forests suggest that recruitment is not a major concern and herbivore damage appears to be having a minimal effect on the forest.

Beaver-mediated lateral hydrologic connectivity, fluvial carbon and nutrient flux, and aquatic ecosystem metabolism

NASA Astrophysics Data System (ADS)

Wegener, Pam; Covino, Tim; Wohl, Ellen

2017-06-01

River networks that drain mountain landscapes alternate between narrow and wide valley segments. Within the wide segments, beaver activity can facilitate the development and maintenance of complex, multithread planform. Because the narrow segments have limited ability to retain water, carbon, and nutrients, the wide, multithread segments are likely important locations of retention. We evaluated hydrologic dynamics, nutrient flux, and aquatic ecosystem metabolism along two adjacent segments of a river network in the Rocky Mountains, Colorado: (1) a wide, multithread segment with beaver activity; and, (2) an adjacent (directly upstream) narrow, single-thread segment without beaver activity. We used a mass balance approach to determine the water, carbon, and nutrient source-sink behavior of each river segment across a range of flows. While the single-thread segment was consistently a source of water, carbon, and nitrogen, the beaver impacted multithread segment exhibited variable source-sink dynamics as a function of flow. Specifically, the multithread segment was a sink for water, carbon, and nutrients during high flows, and subsequently became a source as flows decreased. Shifts in river-floodplain hydrologic connectivity across flows related to higher and more variable aquatic ecosystem metabolism rates along the multithread relative to the single-thread segment. Our data suggest that beaver activity in wide valleys can create a physically complex hydrologic environment that can enhance hydrologic and biogeochemical buffering, and promote high rates of aquatic ecosystem metabolism. Given the widespread removal of beaver, determining the cumulative effects of these changes is a critical next step in restoring function in altered river networks.

Proximate composition and physicochemical properties of European beaver (Castor fiber L.) meat.

PubMed

Florek, Mariusz; Drozd, Leszek; Skałecki, Piotr; Domaradzki, Piotr; Litwińczuk, Anna; Tajchman, Katarzyna

2017-01-01

The proximate composition of meat from young and mature European beaver and physicochemical properties during storage were investigated. The young beaver meat contains 20.52g of protein and 1.86g of fat in 100g, while mature animals 22.16g and 0.73g. Index of nutritional quality for protein ranged from 2.03 to 2.24. Storage had a greater impact on the physicochemical properties of beaver meat than animal age and muscle type. The meat of mature beavers was significantly (P<0.05) darker (L*=28.51) in comparison with young animals (L*=30.79) and contained significantly (P<0.01) more total pigments. However, the negative b* values (between -2.05 and -2.19) indicated a bluish tint on the surface of beaver meat. The significantly (P<0.05) lower drip loss and cooking loss showed semimembranosus (0.65% and 17.89%) compared to longissimus thoracis et lumborum muscle (0.84% and 19.58%). Significantly (P<0.01) lower values of TBARS, drip loss and cooking loss were determined in meat at 24h (0.15mgMDAkg -1 , 0.59% and 15.99%) in comparison with stored for 7days (0.46mgMDAkg -1 , 0.90% and 21.49%). Generally, storage for 7days improved meat water holding capacity and tenderness. W-B shear force and shear energy of beaver meat decreased from 51.4N and 0.21J at 24h to 33.2N and 0.11J at 7days. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ambient conditions and fate and transport simulations of dissolved solids, chloride, and sulfate in Beaver Lake, Arkansas, 2006--10

USGS Publications Warehouse

Green, W. Reed

2013-01-01

Beaver Lake is a large, deep-storage reservoir located in the upper White River Basin in northwestern Arkansas, and was completed in 1963 for the purposes of flood control, hydroelectric power, and water supply. Beaver Lake is affected by point and nonpoint sources of minerals, nutrients, and sediments. The City of Fayetteville discharges about half of its sewage effluent into the White River immediately upstream from the backwater of the reservoir. The City of West Fork discharges its sewage effluent into the West Fork of the White River, and the City of Huntsville discharges its sewage effluent into a tributary of War Eagle Creek. A study was conducted to describe the ambient conditions and fate and transport of dissolved solids, chloride, and sulfate concentrations in Beaver Lake. Dissolved solids, chloride, and sulfate are components of wastewater discharged into Beaver Lake and a major concern of the drinking water utilities that use Beaver Lake as their source. A two-dimensional model of hydrodynamics and water quality was calibrated to include simulations of dissolved solids, chloride, and sulfate for the period January 2006 through December 2010. Estimated daily dissolved solids, chloride, and sulfate loads were increased in the White River and War Eagle Creek tributaries, individually and the two tributaries together, by 1.2, 1.5, 2.0, 5.0, and 10.0 times the baseline conditions to examine fate and transport of these constituents through time at seven locations (segments) in the reservoir, from upstream to downstream in Beaver Lake. Fifteen dissolved solids, chloride, and sulfate fate and transport scenarios were compared to the baseline simulation at each of the seven downstream locations in the reservoir, both 2 meters (m) below the surface and 2 m above the bottom. Concentrations were greater in the reservoir at model segments closer to where the tributaries entered the reservoir. Concentrations resulting from the increase in loading became more diluted farther downstream from the source. Differences in concentrations between the baseline condition and the 1.2, 1.5, and 2.0 times baseline concentration scenarios were smaller than the differences in the 5.0 and 10.0 times baseline concentration scenarios. The results for both the 2 m below the surface and 2 m above the bottom were similar, with the exception of concentrations resulting from the increased loading factors (5.0 and 10.0 times), where concentrations 2 m above the bottom were consistently greater than those 2 m below the surface at most segments.

Spatial variation in fish assemblages across a beaver-influenced successional landscape

USGS Publications Warehouse

Schlosser, I.J.; Kallemeyn, L.W.

2000-01-01

Beavers are increasingly viewed as “ecological engineers,” having broad effects on physical, chemical, and biological attributes of north-temperate landscapes. We examine the influence of both local successional processes associated with beaver activity and regional geomorphic boundaries on spatial variation in fish assemblages along the Kabetogama Peninsula in Voyageurs National Park, northern Minnesota, USA. Fish abundance and species richness exhibited considerable variation among drainages along the peninsula. Geological barriers to fish dispersal at outlets of some drainages has reduced fish abundance and species richness. Fish abundance and species richness also varied within drainages among local environments associated with beaver pond succession. Fish abundance was higher in upland ponds than in lowland ponds, collapsed ponds, or streams, whereas species richness was highest in collapsed ponds and streams. Cluster analyses based on fish abundance at sites classified according to successional environment indicated that four species (northern redbelly dace, Phoxinus eos; brook stickleback, Culaea inconstans; finescale dace, P. neogaeus; and fathead minnow, Pimephales promelas), were predominant in all successional environments. Several less abundant species were added in collapsed ponds and streams, with smaller size classes of large lake species (e.g., black crappie, Pomoxis nigromaculatus; smallmouth bass, Micropertus dolomieui; yellow perch, Perca flavescens; and burbot, Lota lota) being a component of these less abundant species. The addition of smaller size classes of large lake species indicates that dispersal of early life-history stages from Kabetogama Lake played a role in determining the species richness and composition of less abundant species in successional environments on the peninsula. Furthermore, collapsed-pond and stream environments closer to Kabetogama Lake had higher species richness than similar successional sites located farther from the lake. Cluster analyses based on fish abundance at sites classified according to drainage indicated that species composition among drainages was influenced both by the presence or absence of geological barriers to fish dispersal and the nonrandom distribution of collapsed ponds and streams. Based on these results, we present a hierarchical conceptual model suggesting how geomorphic boundaries and beaver pond succession interact to influence fish assemblage attributes. The presence of a productive and diverse fish assemblage in headwater streams of north-temperate areas requires the entire spatial and temporal mosaic of successional habitats associated with beaver activity, including those due to the creation and abandonment of beaver ponds. The ultimate impact of the local successional mosaic on fishes, however, will be strongly influenced by the regional geomorphic context in which the mosaic occurs.

Food processing by animals: do beavers leach tree bark to improve palatability?

PubMed

Müller-Schwarze, D; Brashear, H; Kinnel, R; Hintz, K A; Lioubomirov, A; Skibo, C

2001-05-01

Beavers store and consume tree parts in the bodies of water where they live. We examined whether such soaking renders food more palatable by leaching out undesirable compounds. In experiment 1, saplings of red maple, Acer rubrum (RM), were first soaked in a pond for periods of 2, 18, and 36 days, then offered to free-ranging beavers. Soaking for two days rendered RM slightly more acceptable to beavers. To further examine the time window around two days, RM sticks were soaked in distilled water in the laboratory for 1, 2, 4, and 6 days before presenting them to beavers (experiment 2). In experiment 3, twigs of three species were placed on land. Beavers placed RM in the water for 1 to 3 days before consuming the twigs. In experiment 4, sticks were provided in the water at Cranberry Lake Biological Station (CLBS). Most quaking aspen (QA) was consumed during the first night, and most witch hazel, Hamamelis virginiana (WH), during the third night. At Allegany State Park (ASP), no such difference was found. Twigs were provided in the water in experiment 5. At ASP, WH was taken after three days in the water, and at CLBS little WH was consumed, and only during the third night. A meta-analysis of all experiments shows that relatively more WH is consumed after two days than any other species. Experiment 6 traced the time beavers left their own harvested branches in the water. Unlike other tree species, WH remained in the water for two to four days before being consumed. Experiment 7 measured the phenolics leached into water from RM twigs and small pieces of bark soaked for 10 and 8 days, respectively. Shredded bark lost 50-60% of leachable phenolics into the water, and twigs 70-80%. We conclude that beavers can use water to leach undesirable compounds from their food. Although this effect was not robust, our study is the first of its kind.

40 CFR 131.34 - Kansas.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Contact Recreation Basin: Solomon Subbasin: Upper North Fork Solomon Ash Creek 10260011 24 Primary Contact... Recreation Subbasin: Lower North Fork Solomon Beaver Creek 10260012 10 Primary Contact Recreation Beaver...

Using ecosystem engineers as tools in habitat restoration and rewilding: beaver and wetlands.

PubMed

Law, Alan; Gaywood, Martin J; Jones, Kevin C; Ramsay, Paul; Willby, Nigel J

2017-12-15

Potential for habitat restoration is increasingly used as an argument for reintroducing ecosystem engineers. Beaver have well known effects on hydromorphology through dam construction, but their scope to restore wetland biodiversity in areas degraded by agriculture is largely inferred. Our study presents the first formal monitoring of a planned beaver-assisted restoration, focussing on changes in vegetation over 12years within an agriculturally-degraded fen following beaver release, based on repeated sampling of fixed plots. Effects are compared to ungrazed exclosures which allowed the wider influence of waterlogging to be separated from disturbance through tree felling and herbivory. After 12years of beaver presence mean plant species richness had increased on average by 46% per plot, whilst the cumulative number of species recorded increased on average by 148%. Heterogeneity, measured by dissimilarity of plot composition, increased on average by 71%. Plants associated with high moisture and light conditions increased significantly in coverage, whereas species indicative of high nitrogen decreased. Areas exposed to both grazing and waterlogging generally showed the most pronounced change in composition, with effects of grazing seemingly additive, but secondary, to those of waterlogging. Our study illustrates that a well-known ecosystem engineer, the beaver, can with time transform agricultural land into a comparatively species-rich and heterogeneous wetland environment, thus meeting common restoration objectives. This offers a passive but innovative solution to the problems of wetland habitat loss that complements the value of beavers for water or sediment storage and flow attenuation. The role of larger herbivores has been significantly overlooked in our understanding of freshwater ecosystem function; the use of such species may yet emerge as the missing ingredient in successful restoration. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Resurgent beaver ponds in the northeastern United States: implications for greenhouse gas emissions.

PubMed

Lazar, Julia G; Addy, Kelly; Welsh, Molly K; Gold, Arthur J; Groffman, Peter M

2014-11-01

Beaver ponds, a wetland type of increasing density in the northeastern United States, vary spatially and temporally, creating high uncertainty in their impact to greenhouse gas (GHG) emissions. We used floating static gas chambers to assess diffusive fluxes of methane (CH), carbon dioxide (CO), and nitrous oxide (NO) from the air-water interface of three beaver ponds (0.05-8 ha) in Rhode Island from fall 2012 to summer 2013. Gas flux was based on linear changes of gas concentrations in chambers over 1 h. Our results show that these beaver ponds generated considerable CH and CO emissions. Methane flux (18-556 mg m d) showed no significant seasonal differences, but the shallowest pond generated significantly higher CH flux than the other ponds. Carbon dioxide flux (0.5-22.0 g m d) was not significantly different between sites, but it was significantly higher in the fall, possibly due to the degradation of fresh leaves. Nitrous oxide flux was low (0-2.4 mg m d). Overall, CH and CO comprised most of the global warming potential, 61 and 38%, respectively. The shallowness of the beaver ponds may have limited the time needed for CH oxidation to CO before CH escaped to the atmosphere. Beaver dams also increase the aerial extent of hydric soils, which may transform riparian areas from upland GHG sinks to wetland GHG sources thereby changing the net global warming potential. Further studies tracking the pattern and conditions of beaver pond creation and abandonment will be essential to understanding their role as GHG sources. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Records of water-level measurements in wells in the Oklahoma panhandle, 1966-70

USGS Publications Warehouse

Hart, Donald L.

1972-01-01

Investigations of the ground-water resources of the Oklahoma panhandle by the U.S. Geological Survey in cooperation with the Oklahoma Water Resources Board includes collection of water-level records; the systematic collection of these records began in 1937. Records of many shallow wells were compiled in 1937 and periodic measurements were made in a few wells until 1966. Owing to the heavy development of irrigation during the 1960's (fig. 1) an expanded network of observation wells established in Texas County in 1966 and in Beaver and Cimarron Counties in 1967; measurement of water levels have been made on an annual basis since those times. This report contains water-level records for the period 1966-70 in Texas County, and for the period 1967-70 in Beaver and Cimarron Counties. At the present time (1971) the annual observation-well network includes 528 wells, of which 98 are in Beaver County, 211 are in Cimarron County, and 219 are in Texas County. These data provide an index to available ground-water supplies; they will be useful in planning and studying water resources development; and they will serve as a framework of data for the detailed hydrologic investigation now in progress in the panhandle. (available as photostat copy only)

Records of water-level measurements in wells in the Oklahoma panhandle, 1971-72

USGS Publications Warehouse

Hart, Donald L.; Hoffman, George L.; Goemaat, Robert L.

1972-01-01

Investigations of the ground-water resources of the Oklahoma panhandle by the U.S. Geological Survey in cooperation with the Oklahoma Water Resources Board includes collection of water-level records; the systematic collection of these records began in 1937. Records of many shallow wells were compiled in 1937 and periodic measurements were made in a few wells until 1966. Owing to the heavy development of irrigation during the 1960's (fig. 1) an expanded network of observation wells established in Texas County in 1966 and in Beaver and Cimarron Counties in 1967; measurement of water levels have been made on an annual basis since those times.This report contains water-level records for the period 1971-72 and the water-level change for the period 1966-72 in Texas County, and for the period 1967-72 in Beaver and Cimarron Counties. At the present time (1972) the annual observation-well network includes 521 wells, of which 97 are in Beaver County, 203 are in Cimarron County, and 221 are in Texas County. These data provide an index to available ground-water supplies; they will be useful in planning and studying water resources development; and they will serve as a framework of data for the detailed hydrologic investigation now in progress in the panhandle.

Collection of short papers on Beaver Creek watershed studies in West Tennessee, 1989-94

USGS Publications Warehouse

Doyle, W. Harry.; Baker, Eva G.

1995-01-01

In 1989, the U.S. Geological Survey began a scientific investigation to evaluate the effect of agricultural activities on water quality and the effectiveness of agricultural best management practices in the Beaver Creek watershed, West Tennessee. The project is being conducted jointly with other Federal, State, county agencies, the farming community, and academic institutions, in support of the U.S. Department of Agriculture's Hydrologic Unit Area program. The Beaver Creek project has evolved into a long-term watershed assessment and monitoring program. In 1991, a grant was received to develop and evaluate sampling strategies for higher order streams. During the summer of 1992, a reconnaissance of water-quality conditions for the shallow aquifers in Shelby, Tipton, Fayette, and Haywood Counties was conducted and included 89 domestic wells in the Beaver Creek watershed. Results from this effort lead to the development of a 1-year program to evaluate cause- and-effect relations that can explain the observed water-quality conditions for the shallow aquifers in the watershed. In 1992 the USGS, in cooperation with the Soil Conservation Service and the Shelby County Soil Conservation District, began an evaluation of in-stream processes and in-stream resource-management systems. In 1993, a biomonitoring program was established in the watershed. This collection of eight articles and abstracts was originally published in the American Water Resources Association National Symposium on Water Quality Proceedings for the national conference held in Chicago in 1994 and describes what has been learned in the study to date.

Sedimentation rates and patterns in beaver ponds in a mountain environment

NASA Astrophysics Data System (ADS)

Butler, David R.; Malanson, George P.

1995-09-01

Sediment depth was measured at several sites within each of eight beaver ponds in Glacier National Park, Montana, and sediment samples wen; collected from five of these ponds. Accumulation rates of sediments far exceeded published rates from boreal forest landscapes in eastem and central North America. Pond area strongly predicts volume of sedimentation. Textural differences illustrated spatial variations associated with position in a pond and along a pond sequence. Organic matter content was significantly higher in older ponds, and has ramifications for the development of the benthos and the long-term storage of matter in ponds. The role of beavers as biogeomorphic agents is profound, but requires further elucidation to distinguish between fluvial sediment deposition in ponds and sediment deposition associated with beaver excavational activity.

Vascular Plant and Vertebrate Inventory of Montezuma Castle National Monument

USGS Publications Warehouse

Schmidt, Cecilia A.; Drost, Charles A.; Halvorson, William Lee

2006-01-01

Executive Summary We summarize past inventory efforts for vascular plants and vertebrates at Montezuma Castle National Monument (NM) in Arizona. We used data from previous research to compile complete species lists for the monument and to assess inventory completeness. There have been 784 species recorded at Montezuma Castle NM, of which 85 (11%) are non-native. In each taxon-specific chapter we highlight areas of resources that contributed to species richness or unique species for the monument. Of particular importance are Montezuma Well and Beaver and Wet Beaver creeks and the surrounding riparian vegetation, which are responsible for the monument having one of the highest numbers of bird species in the Sonoran Desert Network of park units. Beaver Creek is also home to populations of federally-listed fish species of concern. Other important resources include the cliffs along the creeks and around Montezuma Well (for cliff and cave roosting bats). Based on the review of past studies, we believe the inventory for most taxa is nearly complete, though some rare or elusive species will be added with additional survey effort. We recommend additional inventory, monitoring and research studies.

Constituent concentrations, loads, and yields to Beaver Lake, Arkansas, water years 1999-2008

USGS Publications Warehouse

Bolyard, Susan E.; De Lanois, Jeanne L.; Green, W. Reed

2010-01-01

Beaver Lake is a large, deep-storage reservoir used as a drinking-water supply and considered a primary watershed of concern in the State of Arkansas. As such, information is needed to assess water quality, especially nutrient enrichment, nutrient-algal relations, turbidity, and sediment issues within the reservoir system. Water-quality samples were collected at three main inflows to Beaver Lake: the White River near Fayetteville, Richland Creek at Goshen, and War Eagle Creek near Hindsville. Water-quality samples collected over the period represented different flow conditions (from low to high). Constituent concentrations, flow-weighted concentrations, loads, and yields from White River, Richland Creek, and War Eagle Creek to Beaver Lake for water years 1999-2008 were documented for this report. Constituents include total ammonia plus organic nitrogen, dissolved nitrite plus nitrate nitrogen, dissolved orthophosphorus (soluble reactive phosphorus), total phosphorus, total nitrogen, dissolved organic carbon, total organic carbon, and suspended sediment. Linear regression models developed by computer program S-LOADEST were used to estimate loads for each constituent for the 10-year period at each station. Constituent yields and flow-weighted concentrations for each of the three stations were calculated for the study. Constituent concentrations and loads and yields varied with time and varied among the three tributaries contributing to Beaver Lake. These differences can result from differences in precipitation, land use, contributions of nutrients from point sources, and variations in basin size. Load and yield estimates varied yearly during the study period, water years 1999-2008, with the least nutrient and sediment load and yields generally occurring in water year 2006, and the greatest occurring in water year 2008, during a year with record amounts of precipitation. Flow-weighted concentrations of most constituents were greatest at War Eagle Creek near Hindsville than White River near Fayetteville and Richland Creek at Goshen. Loads and yields of most constituents were greater at the War Eagle Creek and White River stations than at the Richland Creek Station.

Effect of browsing on willow in the Steel Creek grazing allotment

USGS Publications Warehouse

Keigley, R.B.; Gale, Gil

2000-01-01

View upstream from the study area. Salix geyerriana is the dominant willow species. Salix drummondiana and S. Boothii are less common; older individuals of both species grow to about 2-m tall. Salix bebbiana is much less common, and where present, is browsed close to ground level. The carcass of an old Bebb willow that had attained typical stature is located near the study area. Beaver are absent. The remains of relic beaver dams indicate that beaver were once an important hydrologic influence.

Beaver lodge location on the upstream Loire River.

PubMed

Fustec, Joëlle; Cormier, Jean-Paul; Lodé, Thierry

2003-08-01

In the part of the Loire River recently colonized by Eurasian beavers, we compared habitat characteristics among sites with lodges, sites with cut trees and sites without beaver. The absence of sandbank and canopy cover (by 10-15-m tall trees, by tall Salicaceae, and by bushy Salicaceae) appeared as good predictors for lodge settling. Based on this model, the number of proper lodge sites was estimated for the next downstream 36 kilometers stretch. The number of favourable sites decreases as anthropization increases.

Research notes : beaver bafflers.

DOT National Transportation Integrated Search

2001-05-01

Historically, highway maintenance forces have had to remove beaver dams from roadside culverts each year. The dams can create significant pools, saturating and weakening the roadway structure. If not removed, the water behind the dam can cover the hi...

Influence of Fiber Type Composition and Capillary Density on Onset of Blood Lactate Accumulation,

DTIC Science & Technology

1981-03-25

changes referred to as aerobic and anaerobic thresholds as suggested by e.g. Skinner and McLellan (32). To assess the "breaking point", which re- presents...in man. Acta Physiol Scand Suppl 443, 1976. 37 Wasserman K., Whipp B., Koyal S., Beaver t’. : Anaerobic threshold and respiratory gas exchange during...onset of a net accumulation of lactate in blood, has been proposed to represent a metabolic shift from aerobic to revalent anaerobic energy contribution

Habitat Suitability Index Models: Beaver

USGS Publications Warehouse

Allen, Arthur W.

1982-01-01

Habitat preferences of the beaver (Castor canadensis) are described in this publication, which is one of a series of Habitat Suitability Index (HSI) models. Habitat use information is presented in a synthesis of the literature on the species-habitat requirements of the beaver, followed by the development of the HSI model. The model is designed to provide information for use in impact assessment and habitat management activities, and should be used in conjunction with habitat evaluation procedures previously developed by the Fish and Wildlife Service. This revised model updates the original publication dated September 1982.

Publications - GMC 92 | Alaska Division of Geological & Geophysical Surveys

Science.gov Websites

Oil Company Beaver Creek Unit #4 well Authors: Makada, R. Publication Date: 1988 Publisher: Alaska , Vitrinite reflectance data of ditch cuttings from the Marathon Oil Company Beaver Creek Unit #4 well: Alaska

Nitrate-Nitrogen Levels in Rural Drinking Water: Is There an Association with Age-related Macular Degeneration?

PubMed Central

Klein, Barbara E. K.; McElroy, Jane A.; Klein, Ronald; Howard, Kerri P.; Lee, Kristine E.

2014-01-01

We examined the association of nitrate-nitrogen exposure from rural private drinking water and incidence of age-related macular degeneration (AMD). Participants of the Beaver Dam Eye Study living in rural areas within the 53916 zone improvement plan code but outside the city limits of Beaver Dam, Wisconsin (Beaver Dam Township) completed a questionnaire and ocular examination including standardized, graded fundus photographs at five examinations. Data from an environmental monitoring study with probabilistic-based agro-chemical sampling, including nitrate-nitrogen, of rural private drinking water were available. Incidence of early AMD was associated with elevated nitrate-nitrogen levels in rural private drinking water supply (10.0% for low, 19.2% for medium, and 26.1% for high nitrate-nitrogen level in the right eye). The odds ratios (ORs) were 1.77 (95% confidence interval [CI]: 1.12–2.78) for medium and 2.88 (95% CI: 1.59–5.23) for high nitrate-nitrogen level. Incidence of late AMD was increased for those with medium or high levels of nitrate-nitrogen compared to low levels (2.3% for low and 5.1% for the medium or high nitrate-nitrogen level, for the right eye). The OR for medium or high nitrate-nitrogen groups was 2.80 (95% CI: 1.07–7.31) compared to the low nitrate-nitrogen group. PMID:24007430

Beaver herbivory of willow under two flow regimes: A comparative study on the Green and Yampa rivers

USGS Publications Warehouse

Breck, Stewart W.; Wilson, Kenneth R.; Andersen, Douglas C.

2003-01-01

The effect of flow regulation on plant-herbivore ecology has received very little attention, despite the fact that flow regulation can alter both plant and animal abundance and environmental factors that mediate interactions between them. To determine how regulated flows have impacted beaver (Castor canadensis) and sandbar willow (Salix exigua) ecology, we first quantified the abundance and mapped the spatial distribution of sandbar willow on alluvial sections of the flow-regulated Green River and free-flowing Yampa River in northwestern Colorado. We then established 16 and 15 plots (1 m × 2.7 m) in patches of willow on the Green and Yampa Rivers, respectively, to determine whether rates of beaver herbivory of willow differed between rivers (Green versus Yampa River), seasons (fall-winter versus spring-summer), and years (spring 1998-spring 1999 versus spring 1999-spring 2000). Areal extent of willow was similar on each river, but Green River willow patches were smaller and more numerous. Beavers cut more stems during fall and winter than spring and summer and cut over 6 times more stems (percentage basis) on the Green River than on the Yampa River. We attribute the between-river difference in herbivory to higher availability of willow, greater beaver density, and lower availability of young Fremont cottonwood (Populus deltoides subsp. wislizenii; an alternative food source) on the Green River. Flow regulation increased willow availability to beaver by promoting the formation of island patches that are continuously adjacent to water and feature a perimeter with a relatively high proportion of willow interfacing with water.

De Novo Genome and Transcriptome Assembly of the Canadian Beaver (Castor canadensis).

PubMed

Lok, Si; Paton, Tara A; Wang, Zhuozhi; Kaur, Gaganjot; Walker, Susan; Yuen, Ryan K C; Sung, Wilson W L; Whitney, Joseph; Buchanan, Janet A; Trost, Brett; Singh, Naina; Apresto, Beverly; Chen, Nan; Coole, Matthew; Dawson, Travis J; Ho, Karen; Hu, Zhizhou; Pullenayegum, Sanjeev; Samler, Kozue; Shipstone, Arun; Tsoi, Fiona; Wang, Ting; Pereira, Sergio L; Rostami, Pirooz; Ryan, Carol Ann; Tong, Amy Hin Yan; Ng, Karen; Sundaravadanam, Yogi; Simpson, Jared T; Lim, Burton K; Engstrom, Mark D; Dutton, Christopher J; Kerr, Kevin C R; Franke, Maria; Rapley, William; Wintle, Richard F; Scherer, Stephen W

2017-02-09

The Canadian beaver ( Castor canadensis ) is the largest indigenous rodent in North America. We report a draft annotated assembly of the beaver genome, the first for a large rodent and the first mammalian genome assembled directly from uncorrected and moderate coverage (< 30 ×) long reads generated by single-molecule sequencing. The genome size is 2.7 Gb estimated by k-mer analysis. We assembled the beaver genome using the new Canu assembler optimized for noisy reads. The resulting assembly was refined using Pilon supported by short reads (80 ×) and checked for accuracy by congruency against an independent short read assembly. We scaffolded the assembly using the exon-gene models derived from 9805 full-length open reading frames (FL-ORFs) constructed from the beaver leukocyte and muscle transcriptomes. The final assembly comprised 22,515 contigs with an N50 of 278,680 bp and an N50-scaffold of 317,558 bp. Maximum contig and scaffold lengths were 3.3 and 4.2 Mb, respectively, with a combined scaffold length representing 92% of the estimated genome size. The completeness and accuracy of the scaffold assembly was demonstrated by the precise exon placement for 91.1% of the 9805 assembled FL-ORFs and 83.1% of the BUSCO (Benchmarking Universal Single-Copy Orthologs) gene set used to assess the quality of genome assemblies. Well-represented were genes involved in dentition and enamel deposition, defining characteristics of rodents with which the beaver is well-endowed. The study provides insights for genome assembly and an important genomics resource for Castoridae and rodent evolutionary biology. Copyright © 2017 Lok et al.

De Novo Genome and Transcriptome Assembly of the Canadian Beaver (Castor canadensis)

PubMed Central

Lok, Si; Paton, Tara A.; Wang, Zhuozhi; Kaur, Gaganjot; Walker, Susan; Yuen, Ryan K. C.; Sung, Wilson W. L.; Whitney, Joseph; Buchanan, Janet A.; Trost, Brett; Singh, Naina; Apresto, Beverly; Chen, Nan; Coole, Matthew; Dawson, Travis J.; Ho, Karen; Hu, Zhizhou; Pullenayegum, Sanjeev; Samler, Kozue; Shipstone, Arun; Tsoi, Fiona; Wang, Ting; Pereira, Sergio L.; Rostami, Pirooz; Ryan, Carol Ann; Tong, Amy Hin Yan; Ng, Karen; Sundaravadanam, Yogi; Simpson, Jared T.; Lim, Burton K.; Engstrom, Mark D.; Dutton, Christopher J.; Kerr, Kevin C. R.; Franke, Maria; Rapley, William; Wintle, Richard F.; Scherer, Stephen W.

2017-01-01

The Canadian beaver (Castor canadensis) is the largest indigenous rodent in North America. We report a draft annotated assembly of the beaver genome, the first for a large rodent and the first mammalian genome assembled directly from uncorrected and moderate coverage (< 30 ×) long reads generated by single-molecule sequencing. The genome size is 2.7 Gb estimated by k-mer analysis. We assembled the beaver genome using the new Canu assembler optimized for noisy reads. The resulting assembly was refined using Pilon supported by short reads (80 ×) and checked for accuracy by congruency against an independent short read assembly. We scaffolded the assembly using the exon–gene models derived from 9805 full-length open reading frames (FL-ORFs) constructed from the beaver leukocyte and muscle transcriptomes. The final assembly comprised 22,515 contigs with an N50 of 278,680 bp and an N50-scaffold of 317,558 bp. Maximum contig and scaffold lengths were 3.3 and 4.2 Mb, respectively, with a combined scaffold length representing 92% of the estimated genome size. The completeness and accuracy of the scaffold assembly was demonstrated by the precise exon placement for 91.1% of the 9805 assembled FL-ORFs and 83.1% of the BUSCO (Benchmarking Universal Single-Copy Orthologs) gene set used to assess the quality of genome assemblies. Well-represented were genes involved in dentition and enamel deposition, defining characteristics of rodents with which the beaver is well-endowed. The study provides insights for genome assembly and an important genomics resource for Castoridae and rodent evolutionary biology. PMID:28087693

75 FR 75945 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-07

... CFR part 10, Environmental Consideration. An environmental impact assessment has not been prepared... mile of Skagit County. east of Beaver Marsh Road. Approximately 1,600 feet 3 +19 east of the intersection of Beaver Marsh Road and Marsh Road. [[Page 75948

Prevalence and degree of hearing loss among males in Beaver Dam cohort: comparison of veterans and nonveterans.

PubMed

Wilson, Richard H; Noe, Colleen M; Cruickshanks, Karen J; Wiley, Terry L; Nondahl, David M

2010-01-01

The Epidemiology of Hearing Loss Study (EHLS) conducted in Beaver Dam, Wisconsin, was a population-based study that focused on the prevalence of hearing loss among 3,753 participants between 1993 and 1995. This article reports the results of several auditory measures from 999 veteran and 590 nonveteran males 48 to 92 years of age included in the EHLS. The auditory measures included pure tone thresholds, tympanometry and acoustic reflexes, word recognition in quiet and in competing message, and the Hearing Handicap Inventory for the Elderly-Screening (HHIE-S) version. Hearing loss in the auditory domains of pure tone thresholds, word recognition in quiet, and word recognition in competing message increased with age but were not significantly different for the veterans and nonveterans. No significant differences were found between participant groups on the HHIE-S; however, regarding hearing aid usage, mixed differences were found.

Water tables constrain height recovery of willow on Yellowstone's northern range.

PubMed

Bilyeu, Danielle M; Cooper, David J; Hobbs, N Thompson

2008-01-01

Excessive levels of herbivory may disturb ecosystems in ways that persist even when herbivory is moderated. These persistent changes may complicate efforts to restore ecosystems affected by herbivores. Willow (Salix spp.) communities within the northern range in Yellowstone National Park have been eliminated or degraded in many riparian areas by excessive elk (Cervus elaphus L.) browsing. Elk browsing of riparian willows appears to have diminished following the reintroduction of wolves (Canis lupis L.), but it remains uncertain whether reduced herbivory will restore willow communities. The direct effects of elk browsing on willows have been accompanied by indirect effects from the loss of beaver (Castor canadensis Kuhl) activity, including incision of stream channels, erosion of fine sediments, and lower water tables near streams historically dammed by beaver. In areas where these changes have occurred, lowered water tables may suppress willow height even in the absence of elk browsing. We conducted a factorial field experiment to understand willow responses to browsing and to height of water tables. After four years of protection from elk browsing, willows with ambient water tables averaged only 106 cm in height, with negligible height gain in two of three study species during the last year of the experiment. Willows that were protected from browsing and had artificially elevated water tables averaged 147 cm in height and gained 19 cm in the last year of the experiment. In browsed plots, elevated water tables doubled height gain during a period of slightly reduced browsing pressure. We conclude that water availability mediates the rate of willow height gain and may determine whether willows grow tall enough to escape the browse zone of elk and gain resistance to future elk browsing. Consequently, in areas where long-term beaver absence has resulted in incised stream channels and low water tables, a reduction in elk browsing alone may not be sufficient for recovery of tall willow stands. Because tall willow stems are important elements of habitat for beaver, mitigating water table decline may be necessary in these areas to promote recovery of historical willow-beaver mutualisms.

40 CFR 80.510 - What are the standards and marker requirements for NRLM diesel fuel and ECA marine fuel?

Code of Federal Regulations, 2010 CFR

2010-07-01

... following areas: (1) Northeast/Mid-Atlantic Area, which includes the following States and counties, through..., Elk, Jefferson, Clarion, Forest, Venango, Mercer, Crawford, Lawrence, Beaver, Washington, and Greene...

Simulation of hydrodynamics, temperature, and dissolved oxygen in Beaver Lake, Arkansas, 1994-1995

USGS Publications Warehouse

Haggard, Brian; Green, W. Reed

2002-01-01

The tailwaters of Beaver Lake and other White River reservoirs support a cold-water trout fishery of significant economic yield in northwestern Arkansas. The Arkansas Game and Fish Commission has requested an increase in existing minimum flows through the Beaver Lake dam to increase the amount of fishable waters downstream. Information is needed to assess the impact of additional minimum flows on temperature and dissolved-oxygen qualities of reservoir water above the dam and the release water. A two-dimensional, laterally averaged hydrodynamic, thermal and dissolved-oxygen model was developed and calibrated for Beaver Lake, Arkansas. The model simulates surface-water elevation, currents, heat transport and dissolved-oxygen dynamics. The model was developed to assess the impacts of proposed increases in minimum flows from 1.76 cubic meters per second (the existing minimum flow) to 3.85 cubic meters per second (the additional minimum flow). Simulations included assessing (1) the impact of additional minimum flows on tailwater temperature and dissolved-oxygen quality and (2) increasing initial water-surface elevation 0.5 meter and assessing the impact of additional minimum flow on tailwater temperatures and dissolved-oxygen concentrations. The additional minimum flow simulation (without increasing initial pool elevation) appeared to increase the water temperature (<0.9 degrees Celsius) and decrease dissolved oxygen concentration (<2.2 milligrams per liter) in the outflow discharge. Conversely, the additional minimum flow plus initial increase in pool elevation (0.5 meter) simulation appeared to decrease outflow water temperature (0.5 degrees Celsius) and increase dissolved oxygen concentration (<1.2 milligrams per liter) through time. However, results from both minimum flow scenarios for both water temperature and dissolved oxygen concentration were within the boundaries or similar to the error between measured and simulated water column profile values.

Effects of reintroduced beaver (Castor canadensis) on riparian bird community structure along the upper San Pedro River, southeastern Arizona and northern Sonora, Mexico

USGS Publications Warehouse

Johnson, Glenn E.; van Riper, Charles

2014-01-01

Chapter 1.—We measured bird abundance and richness along the upper San Pedro River in 2005 and 2006, in order to document how beavers (Castor canadensis) may act as ecosystem engineers after their reintroduction to a desert riparian area in the Southwestern United States. In areas where beavers colonized, we found higher bird abundance and richness of bird groups, such as all breeding birds, insectivorous birds, and riparian specialists, and higher relative abundance of many individual species—including several avian species of conservation concern. Chapter 2.—We conducted bird surveys in riparian areas along the upper San Pedro River in southeastern Arizona (United States) and northern Sonora (Mexico) in order to describe factors influencing bird community dynamics and the distribution and abundance of species, particularly those of conservation concern. These surveys were also used to document the effects of the ecosystem-altering activities of a recently reintroduced beavers (Castor canadensis). Chapter 3.—We reviewed Southwestern Willow Flycatcher (Empidonax traillii extimus) nest records and investigated the potential for future breeding along the upper San Pedro River in southeastern Arizona, where in July 2005 we encountered the southernmost verifiable nest attempt for the species. Continued conservation and management of the area’s riparian vegetation and surface water has potential to contribute additional breeding sites for this endangered Willow Flycatcher subspecies. Given the nest record along the upper San Pedro River and the presence of high-density breeding sites to the north, the native cottonwood-willow forests of the upper San Pedro River could become increasingly important to E. t. extimus recovery, especially considering the anticipated effect of the tamarisk leaf beetle (Diorhabda carinulata) on riparian habitat north of the region.

77 FR 38793 - Northern Natural Gas Company; Notice of Intent To Prepare an Environmental Assessment for the...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-29

... Station near Skellytown, Carson County, Texas, to Northern's Spearman Compressor Station in Spearman... extends from Northern's Beaver Compressor Station near Beaver, Oklahoma, to its Mullinville Compressor Station near Mullinville, Kansas. Activities Northern would conduct related to the [[Page 38794...

78 FR 20244 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Determinations of...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-04

... CFR 51.918), a final determination of attainment suspends the CAA requirements for the Pittsburgh Area... Ozone Standard for the Pittsburgh-Beaver Valley Moderate Nonattainment Area AGENCY: Environmental... determinations regarding the Pittsburgh-Beaver Valley 1997 8-hour ozone nonattainment area (the Pittsburgh Area...

Beaver dams maintain fish biodiversity by increasing habitat heterogeneity throughout a low-gradient stream network

USGS Publications Warehouse

Smith, Joseph M.; Mather, Martha E.

2013-01-01

In summary, within a stream network, beaver dams maintained fish biodiversity by altering in-stream habitat and increasing habitat heterogeneity. Understanding the relationship between habitat heterogeneity and biodiversity can advance basic freshwater ecology and provide science-based support for applied aquatic conservation

Application of a Two-Dimensional Reservoir Water-Quality Model of Beaver Lake, Arkansas, for the Evaluation of Simulated Changes in Input Water Quality, 2001-2003

USGS Publications Warehouse

Galloway, Joel M.; Green, W. Reed

2007-01-01

Beaver Lake is considered a primary watershed of concern in the State of Arkansas. As such, information is needed to assess water quality, especially nutrient enrichment, nutrient-algal relations, turbidity, and sediment issues within the system. A previously calibrated two-dimensional, laterally averaged model of hydrodynamics and water quality was used for the evaluation of changes in input nutrient and sediment concentrations on the water quality of the reservoir for the period of April 2001 to April 2003. Nitrogen and phosphorus concentrations were increased and decreased and tested independently and simultaneously to examine the nutrient concentrations and algal response in the reservoir. Suspended-solids concentrations were increased and decreased to identify how solids are distributed in the reservoir, which can contribute to decreased water clarity. The Beaver Lake model also was evaluated using a conservative tracer. A conservative tracer was applied at various locations in the reservoir model to observe the fate and transport and how the reservoir might react to the introduction of a conservative substance, or a worst-case spill scenario. In particular, tracer concentrations were evaluated at the locations of the four public water-supply intakes in Beaver Lake. Nutrient concentrations in Beaver Lake increased proportionally with increases in loads from the three main tributaries. An increase of 10 times the calibrated daily input nitrogen and phosphorus in the three main tributaries resulted in daily mean total nitrogen concentrations in the epilimnion that were nearly 4 times greater than the calibration concentrations at site L2 and more than 2 times greater than the calibrated concentrations at site L5. Increases in daily input nitrogen in the three main tributaries independently did not correspond in substantial increases in concentrations of nitrogen in Beaver Lake. The greatest proportional increase in phosphorus occurred in the epilimnion at sites L3 and L4 and the least increase occurred at sites L2 and L5 when calibrated daily input phosphorus concentrations were increased. When orthophosphorus was increased in all three tributaries simultaneously by a factor of 10, daily mean orthophosphorus concentrations in the epilimnion of the reservoir were almost 11 times greater than the calibrated concentrations at sites L2 and L5, and 15 times greater in the epilimnion of the reservoir at sites L3 and L4. Phosphorus concentrations in Beaver Lake increased less when nitrogen and phosphorus were increased simultaneously than when phosphorus was increased independently. The greatest simulated increase in algal biomass (represented as chlorophyll a) occurred when nitrogen and phosphorus were increased simultaneously in the three main tributaries. On average, the chlorophyll a values only increased less than 1 microgram per liter when concentrations of nitrogen or phosphorous were increased independently by a factor of 10 at all three tributaries. In comparison, when nitrogen and phosphorus were increased simultaneously by a factor of 10 for all three tributaries, the chlorophyll a concentration increased by about 10 micrograms per liter on average, with a maximum increase of about 57 micrograms per liter in the epilimnion at site L3 in Beaver Lake. Changes in algal biomass with changes in input nitrogen and phosphorus were variable through time in the Beaver Lake model from April 2001 to April 2003. When calibrated daily input nitrogen and phosphorus concentrations were increased simultaneously for the three main tributaries, the increase in chlorophyll a concentration was the greatest in late spring and summer of 2002. Changes in calibrated daily input inorganic suspended solids concentrations were examined because of the effect they may have on water clarity in Beaver Lake. The increase in total suspended solids was greatest in the hypolimnion at the upstream end of Beaver Lake, and negligible changes

Changes in flow in the Beaver-North Canadian River basin upstream from Canton Lake, western Oklahoma

USGS Publications Warehouse

Wahl, Kenneth L.; Tortorelli, Robert L.

1997-01-01

This report presents the results of an evaluation of hydrologic data for the Beaver-North Canadian River basin upstream from Canton Lake in western Oklahoma. It examines the climatic and hydrologic data for evidence of trends. The hydrologic data examined includes total annual flow, base flow, and annual peak discharges. This study was conducted to determine if there is evidence of trends present in hydrologic and climatic data. All available streamflow-gaging station data, with at least 10 or more years of record, were examined for trends. In addition, the data were divided into an 'early' period (ending in 1971), representing conditions before ground-water levels had declined appreciably, and a 'recent' period (1978-1994), reflecting the condition of declining ground-water levels, including the effects of storage reservoirs. Tests for trend, moving averages, and comparisons of median and average flows for an early period (ending in 1971) with those for the recent period (1978-1994) show that the total annual volume of flow and the magnitudes of instantaneous annual peak discharges measured at most gaging stations in the Beaver- North Canadian River basin have decreased in recent years. Precipitation records for the panhandle, however, show no corresponding changes. The changes in flow are most pronounced in the headwaters upstream from Woodward, but also are evident at Woodward and near Seiling, which represents the inflow to Canton Lake. The average annual discharge decreased between the early period and the recent period by the following amounts: near Guymon, 18,000 acre-feet; at Beaver, 68,000 acre-feet; at Woodward, 72,000 acre-feet; and near Seiling, 63,000 acre-feet. These decreases, expressed as a percentage of the average flows for the early period, were 91 percent near Guymon, 82 percent at Beaver, 49 percent at Woodward, and 37 percent near Seiling. The medians of the annual peak discharges decreased from the early period to the recent period by the following amounts: near Guymon, 98 percent; at Beaver, 86 percent; at Woodward, 80 percent; and near Seiling, 53 percent. The Guymon gage is not affected by reservoirs; the other three mainstem gaging stations are influenced by reservoirs, but the decreases in annual peak discharges are greater than can be explained by storage in those reservoirs. Base flows have undergone substantial change, but unlike the annual volumes the base flows show some increases and some decreases. Flow duration analyses show a shift in the distribution of annual flows. Less contribution is coming from large floods that formerly added substantially to the yearly average flows. Near Seiling, for example, the magnitudes of the large flows that occur less than about 20 percent of the time were greatly reduced in the recent period. A primary mechanism producing these decreased streamflows appears to be the depletion of ground water in the High Plains aquifer that underlies more than 90 percent of the basin. Changes in farming and conservation practices and in water use also may be having an effect.

78 FR 72860 - White River National Forest; Summit County, CO; 2013 Arapahoe Basin Improvements EIS

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-04

... experience that A-Basin provides; improve access to Montezuma Bowl; upgrade or remove existing lifts, as... Gullies and one in Beaver Bowl. Currently, The Beavers can be accessed legally through backcountry access... exit the controlled/patrolled portions of A-Basin's operational boundary to access adjacent backcountry...

Revision of Hemiquedius Casey (Staphylinidae, Staphylininae) and a review of beetles dependent on beavers and muskrats in North America

PubMed Central

Brunke, Adam; Smetana, Aleš; Carruthers-Lay, Duncan; Buffam, Joel

2017-01-01

Abstract Based on newly discovered characters on the male genitalia, external morphology and an accumulation of ecological data, we revise the single member of the genus Hemiquedius. Two new species, H. infinitus Brunke & Smetana, sp. n. and H. castoris Brunke & Smetana, sp. n., from eastern North America are described, and H. ferox (LeConte), restricted to peninsular Florida, is re-described. Hemiquedius castoris is strongly associated with the microhabitats provided by nest materials of the North American beaver and muskrat. A key to the three species of Hemiquedius is provided and diagnostic characters are illustrated. We also review the beetles known to be obligate associates of beavers and muskrats, and discuss the potential role of these keystone vertebrates in beetle evolution and distribution. Based on nest-associated beetles and their closest living relatives, beaver and muskrat lodges may extend distributions northward by moderating winters, promote sympatric speciation and act as refugia against extinction of lineages on a broader timescale. Further research into these potential impacts by ecologists and evolutionary biologists is encouraged. PMID:29118599

Revision of Hemiquedius Casey (Staphylinidae, Staphylininae) and a review of beetles dependent on beavers and muskrats in North America.

PubMed

Brunke, Adam; Smetana, Aleš; Carruthers-Lay, Duncan; Buffam, Joel

2017-01-01

Based on newly discovered characters on the male genitalia, external morphology and an accumulation of ecological data, we revise the single member of the genus Hemiquedius . Two new species, H. infinitus Brunke & Smetana, sp. n. and H. castoris Brunke & Smetana, sp. n. , from eastern North America are described, and H. ferox (LeConte), restricted to peninsular Florida, is re-described. Hemiquedius castoris is strongly associated with the microhabitats provided by nest materials of the North American beaver and muskrat. A key to the three species of Hemiquedius is provided and diagnostic characters are illustrated. We also review the beetles known to be obligate associates of beavers and muskrats, and discuss the potential role of these keystone vertebrates in beetle evolution and distribution. Based on nest-associated beetles and their closest living relatives, beaver and muskrat lodges may extend distributions northward by moderating winters, promote sympatric speciation and act as refugia against extinction of lineages on a broader timescale. Further research into these potential impacts by ecologists and evolutionary biologists is encouraged.

Operation Plans for Anadromous Fish Production Facilities in the Columbia River Basin : Annual Report 1995 : Volume III - Washington.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Colville Confederated Tribes; US Fish and Wildlife Service; Washington Department of Fish and Wildlife

1996-06-01

Beaver Creek Hatchery is located on the Elochoman River about 10 miles upstream from the river mouth. The Elochoman River is a north bank tributary of the lower Columbia River, just downstream of Cathlamet, Washington. The facility consists of 10 intermediate raceways, 20 raceways, (1) earthen rearing pond, (2) adult holding ponds, and a hatchery building with 60 troughs. It is staffed with 4 FTE`s. Water rights total 16,013 gpm from three sources: Elochoman River, Beaver Creek and a well. Beaver Creek water is gravity flow while the other two sources are pumped. The Elochoman River is used in summermore » and fall while Beaver Creek water is used from mid-November through mid-May. Filtered well water (1 cfs) is used to incubate eggs and for early rearing of fry. Water use in summer is about 5,800 gpm. Gobar Pond, a 0.93-acre earthen rearing pond located on Gobar Creek (Kalama River tributary), is operated as a satellite facility.« less

Long-Term Hydrological Reconstruction From a Beaver Meadow Using Testate Amoebae

NASA Astrophysics Data System (ADS)

Von Ness, K.; Loisel, J.; Karran, D. J.; Westbrook, C.; Kohlmeyer, C.

2016-12-01

Beaver ponds contribute up to 0.8 Tg/yr of atmospheric methane (CH4) globally (Whitfield et al., 2014) and were found to be the largest CH4 emitters among all the wetland types in boreal environments (Roulet et al., 1992). However, the sources and underlying mechanisms of carbon emission and sequestration in beaver ponds requires further elucidation. Here we present the historical development of a beaver meadow located in the Sibbald Research Wetland in the Rocky Mountains of Kananaskis Provincial Park, Alberta, Canada. We use a combination of testate amoebae, plant macrofossils, and other geochemical proxies to provide high-resolution reconstructions along three peat cores extracted in hydrologically distinct portions of the meadow. To our knowledge, this is the first attempt at reconstructing long-term hydrological conditions in these systems. Testate amoebae (Protozoa: Rhizopoda) are single-celled organisms that inhabit moist substrates and produce a decay-resistant test. As each taxon generally occupies a discrete ecological niche related to soil moisture and pH, testate amoebae are good indicators of past and ongoing hydrological change. Preliminary analysis of testate amoebae assemblages downcore suggests that this proxy is suitable to reconstruct hydrological changes in meadows, with wetter and drier communities being in good agreement with wetter and drier plant macrofossil assemblages. The nitrogen isotopic signature of peat samples (ongoing) will be used as a proxy for changes in nutrient input; it could become a proxy for past beaver activity.

The Effect of Beaver Activity on the Ammonium Uptake and Water Residence Time Characteristics of a Third-Order Stream Reach

NASA Astrophysics Data System (ADS)

Briggs, M.; Gooseff, M. N.; Wollheim, W. M.; Peterson, B. J.; Morkeski, K.

2009-12-01

Increasing beaver populations within low gradient basins in the northeastern United States are fundamentally changing the way water and dissolved nutrients are exported through these stream networks to the coast. Beaver dams can increase water residence time and contact with organic material, promote anoxic conditions and enhance both surface and hyporheic transient storage; all of these may have an impact on biogeochemical reactivity and nutrient retention. To quantitatively assess some of these effects we co-injected NaCl and NH4+ into the same 3rd-order stream reach in Massachusetts, USA under pre- and post-dam conditions. These experiments were done at similar discharge rates to isolate the impacts of a large natural beaver dam (7 m X 1.3 m) on the low-gradient (0.002) system where variable discharge also imparts a strong control on residence time. During the post-dam experiment there was an estimated 2300 m3 of water impounded behind the structure, which influenced more than 300 m of the 650 m stream reach. Our results showed that median transport time through the reach increased by 160% after dam construction. Additionally the tracer tailing time normalized to the corresponding median transport time increased from 1.08 to 1.51, indicating a pronounced tailing of the tracer signal in the post-dam condition. Data collected within the beaver pond just upstream of the dam indicated poor mixing and the presence of preferential flow paths through the generally stagnant zone. The uptake length (Sw) for NH4+ was 1250 m under the pre-dam condition, and may have changed for the post-dam reach in part because of the observed changes in residence time. As beaver population growth continues within these basins the consequences may be a smoothing of the outlet hydrograph and increased nutrient and organic matter removal and storage along the stream network.

Aquatic habitats of Canaan Valley, West Virginia: Diversity and environmental threats

USGS Publications Warehouse

Snyder, C.D.; Young, J.A.; Stout, B. M.

2006-01-01

We conducted surveys of aquatic habitats during the spring and summer of 1995 in Canaan Valley, WV, to describe the diversity of aquatic habitats in the valley and identify issues that may threaten the viability of aquatic species. We assessed physical habitat and water chemistry of 126 ponds and 82 stream sites, and related habitat characteristics to landscape variables such as geology and terrain. Based on our analyses, we found two issues likely to affect the viability of aquatic populations in the valley. The first issue was acid rain and the extent to which it potentially limits the distribution of aquatic and semi-aquatic species, particularly in headwater portions of the watershed. We estimate that nearly 46%, or 56 kilometers of stream, had pH levels that would not support survival and reproduction of Salvelinuw fontinalis (brook trout), one of the most acid-tolerant fishes in the eastern US. The second issue was the influence of Castor canadensis (beaver) activity. In the Canaan Valley State Park portion of the valley, beaver have transformed 4.7 kilometers of stream (approximately 17% of the total) to pond habitat through their dam building. This has resulted in an increase in pond habitat, a decrease in stream habitat, and a fragmented stream network (i.e., beaver ponds dispersed among stream reaches). In addition, beaver have eliminated an undetermined amount of forested riparian area through their foraging activities. Depending on the perspective, beaver-mediated changes can be viewed as positive or negative. Increases in pond habitat may increase habitat heterogeneity with consequent increases in biological diversity. In contrast, flooding associated with beaver activity may eliminate lowland wetlands and associated species, create barriers to fish dispersal, and possibly contribute to low dissolved oxygen levels in the Blackwater River. We recommend that future management strategies for the wildlife refuge be viewed in the context of these two issues, and that the responses of multiple assemblages be incorporated in the design of refuge management plans.

NASA AIRS Instrument Sees Spread of Pollution from Western Wildfires

NASA Image and Video Library

2013-08-27

This frame from a movie was produced with data from NASA Aqua spacecraft showing the spread of carbon monoxide pollution across North America from fires in the Western U.S., including the Beaver Creek Fire in Idaho and the Rim Fire in California.

Options for managing early-successional forest and shrubland bird habitats in the northeastern United States

Treesearch

Richard M. DeGraaf; Mariko Yamasaki

2003-01-01

Historically, forests in the northeastern United States were disturbed by fire, wind, Native American agriculture, flooding, and beavers (Castor canadensis). Of these, wind and beavers are now the only sources of natural disturbance. Most disturbance-dependent species, especially birds, are declining throughout the region whereas species affiliated with mature forests...

CPHC/WFO Honolulu Gallery

Science.gov Websites

another search. Multiple locations were found. Please select one of the following: Close Location Help Top view Zoom in shot of snow on the Big Island Summits 11/5/2007 (photo by Andrew Beavers (NWS)) Zoom in shot of snow on the Big Island Summits 11/5/2007 (photo by Andrew Beavers (NWS)) Click for larger view

Reproductive characteristics of the Point Arena mountain beaver (Aplodontia rufa nigra)

Treesearch

William Zielinski; M. J. Mazurek

2016-01-01

Little is known about the ecology and life history of the federally endangered Point Arena mountain beaver (Aplodontia rufa nigra). The distribution of this primitive burrowing rodent is disjunct from the balance of the species’ range and occurs in a unique maritime environment of coastal grasslands and forests. Fundamental to protecting this taxon...

75 FR 6736 - FirstEnergy Nuclear Operating Company, FirstEnergy Nuclear Generation Corp., Ohio Edison Company...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-10

..., Beaver Valley Power Station, Unit Nos. 1 and 2; Environmental Assessment and Finding of No Significant Impact The U.S. Nuclear Regulatory Commission (NRC) is considering issuance of an exemption, pursuant to... Operating Company (licensee), for operation of the Beaver Valley Power Station, Unit Nos. 1 and 2 (BVPS-1...

76 FR 55233 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-07

... as the anticipated impact is so minimal. For the same reason, the FAA certifies that this amendment will not have a significant economic impact on a substantial number of small entities under the... Rgnl, Takeoff Minimums and Obstacle DP, Orig Beaver Falls, PA, Beaver County, LOC RWY 10, Amdt 4...

Development and characterization of microsatellite markers in the Point Arena mountain beaver Aplodontia rufa nigra

Treesearch

Kristine L. Pilgrim; William J. Zielinski; Mary J. Mazurek; Frederick V. Schlexer; Michael K. Schwartz

2006-01-01

The Point Arena mountain beaver (Aplodontia rufa nigra) is an endangered subspecies. Efforts to recover this sub-species will be aided by advances in molecular genetics, specifically the ability to estimate population size using noninvasive genetic sampling. Here we report on the development of nine polymorphic loci for the Point Arena mountain...

Multiple resource evaluations on the Beaver Creek watershed: An Annotated Bibliography (1956-1996)

Treesearch

M. B. Baker; P. F. Ffolliott

1998-01-01

The Beaver Creek experimental watershed, located in north-central Arizona, was established in 1956 in response to public concerns that the flow of streams and the amount of livestock forage on watersheds in the Salt-Verde River Basins were being reduced by increasing densities of ponderosa pine saplings and pinyon-juniper trees. Natural resource responses to the...

Estimating abundance and survival in the endangered Point Arena Mountain beaver using noninvasive genetic methods

Treesearch

William J. Zielinski; Fredrick V. Schlexer; T. Luke George; Kristine L. Pilgrim; Michael K. Schwartz

2013-01-01

The Point Arena mountain beaver (Aplodontia rufa nigra) is federally listed as an endangered subspecies that is restricted to a small geographic range in coastal Mendocino County, California. Management of this imperiled taxon requires accurate information on its demography and vital rates. We developed noninvasive survey methods, using hair snares to sample DNA and to...

Influence of flooding, freezing, and American beaver herbivory on survival of planted oak seedlings

Treesearch

Johnathan T. Reeves; Andrew W. Ezell; John D. Hodges; Emily B. Schultz; Andrew B. Self

2016-01-01

Good seedlings, proper planting, and competition control normally result in successful hardwood planting. However, other factors can have serious impact on planting success, such as the impact of flooding, freezing, and the American beaver (Castor canadensis). In 2014, three planting stocks of Nuttall oak (Quercus nuttallii) and Shumard oak (

The Relationship between Market and Accounting Determined Risk Measures: Reviewing and Updating the Beaver, Kettler, Scholes (1970) Study

ERIC Educational Resources Information Center

Jarvela, Michael; Kozyra, James; Potter, Carla

2009-01-01

The association between market-determined risk measures and accounting-determined risk measures was originally explored in the 1970s by Beaver, Kettler, and Scholes (BKS). The results of the BKS (1970) study suggest that accounting information is usefulness in assessing firm specific risk. Since BKS, there have been few studies conducted to…

A range-wide occupancy estimate and habitat model for the endangered Point Arena mountain beaver (Aplodontia rufa nigra)

Treesearch

William J. Zielinski; Fredrick V. Schlexer; Jeffrey R. Dunk; Matthew J. Lau; James J. Graham

2015-01-01

The mountain beaver (Aplodontia rufa) is notably the most primitive North American rodent with a restricted distribution in the Pacific Northwest based on its physiological limits to heat stress and water needs. The Point Arena subspecies (A. r. nigra) is federally listed as endangered and is 1 of 2 subspecies that have extremely...

Recycling at Penn State's Beaver Stadium. "Recycle on the Go" Success Story

ERIC Educational Resources Information Center

US Environmental Protection Agency, 2009

2009-01-01

With a 13-year-old recycling program, The Pennsylvania State University's (Penn State) Beaver Stadium in the past diverted nearly 30 tons of recyclables per year from local landfills. A new initiative to promote recycling in the stadium's tailgating area has helped Penn State more than triple its old recycling record, collecting 112 tons in 2008.…

75 FR 8107 - Bond Swamp National Wildlife Refuge, Bibb and Twiggs Counties, GA

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-23

... impact. SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce the availability of our final comprehensive Conservation Plan (CCP) and finding of no significant impact (FONSI) for the environmental..., including upland mixed pine/hardwood, bottomland hardwood, and tupelo gum swamp forests. Creeks, beaver...

Using a National Park for a Field Trip

ERIC Educational Resources Information Center

Baer, Roy K.

1977-01-01

Describes a one-week camping trip to Acadia National Park (Maine) as a non-credit educational experience. Includes activities such as population studies in intertidal zones, wild life sketching, nature list hikes (forest devastation by fire, beaver ponds, glacial ponds and streams), fishing and clamming rips, and student projects. (CS)

Small geographic range but not panmictic: how forests structure the endangered Point Arena mountain beaver (Aplodontia rufa nigra)

Treesearch

William J. Zielinski; Fredrick V. Schlexer; Sean A. Parks; Kristine L. Pilgrim; Michael K. Schwartz

2012-01-01

The landscape genetics framework is typically applied to broad regions that occupy only small portions of a species' range. Rarely is the entire range of a taxon the subject of study. We examined the landscape genetic structure of the endangered Point Arena mountain beaver (Aplodontia rufa nigra), whose isolated geographic range is found in a...

Hydrogeology, water quality, and ground-water development alternatives in the Beaver-Pasquiset ground-water reservoir, Rhode Island

USGS Publications Warehouse

Dickerman, D.C.; Ozbilgin, M.M.

1985-01-01

In a 23 sq mi study area, the Beaver-Pasquiset groundwater reservoir within the Pawcatuck River basin in southern Rhode Island, stratified drift is the only principal geologic unit capable of producing yields > 350 gal/min. Transmissivity of the aquifer ranges from 7,200 to 24,300 sq ft/day. Water table conditions prevail in the aquifer, which is in good hydraulic connection with perennial streams and ponds. A digital model of two-dimensional groundwater flow was used to simulate the interaction between surface water and groundwater, and to evaluate the impact of alternative schemes of groundwater development on groundwater levels, pond levels, and streamflow in the Beaver-Pasquiset groundwater reservoir. Transient simulations of theoretical pumpage were made for a drought period (1963-66) and a wet period (1976-78). The areas most favorable for development of high-capacity wells (350 gal/min or more) are along the Beaver River and near Pasquiset Pond. The water is soft and generally contains < 100 mg/L dissolved solids. Locally, groundwater contains elevated concentrations of iron and manganese (7.5 and 3.7 mg/L, respectively), southeast of Pasquiset Pond, and will require treatment if used for public supply. The groundwater reservoir was simulated with a two-dimensional finite-difference model using a block-centered grid consisting of 33 rows and 75 columns. Differences between measured and simulated water table altitudes for the final steady state run for 21 selected observation wells averaged +0.07 ft. Combined pumping rates for simulation of groundwater development alternatives at eight sites ranged from 3.25 to 7.00 Mgal/d. Pumping rates for individual wells ranged from 0.25 to 1.50 Mgal/d. Transient simulations suggest that the Beaver-Pasquiset groundwater reservoir is capable of sustaining a pumping rate of 4.25 Mgal/d during years of average groundwater recharge with minimal impact on groundwater levels, pond levels, and streamflow. During extreme drought periods (1965 and 1966) it would be necessary to reduce pumpage below 3.25 Mgal/d to maintain flow in both the Beaver River and Pasquiset Brook. (Author 's abstract)

Echinococcus multilocularis Detection in Live Eurasian Beavers (Castor fiber) Using a Combination of Laparoscopy and Abdominal Ultrasound under Field Conditions

PubMed Central

Gottstein, Bruno; Cracknell, John; Schwab, Gerhard; Rosell, Frank

2015-01-01

Echinococcus multilocularis is an important pathogenic zoonotic parasite of health concern, though absent in the United Kingdom. Eurasian beavers (Castor fiber) may act as a rare intermediate host, and so unscreened wild caught individuals may pose a potential risk of introducing this parasite to disease-free countries through translocation programs. There is currently no single definitive ante-mortem diagnostic test in intermediate hosts. An effective non-lethal diagnostic, feasible under field condition would be helpful to minimise parasite establishment risk, where indiscriminate culling is to be avoided. This study screened live beavers (captive, n = 18 or wild-trapped in Scotland, n = 12) and beaver cadavers (wild Scotland, n = 4 or Bavaria, n = 11), for the presence of E. multilocularis. Ultrasonography in combination with minimally invasive surgical examination of the abdomen by laparoscopy was viable under field conditions for real-time evaluation in beavers. Laparoscopy alone does not allow the operator to visualize the parenchyma of organs such as the liver, or inside the lumen of the gastrointestinal tract, hence the advantage of its combination with abdominal ultrasonography. All live beavers and Scottish cadavers were largely unremarkable in their haematology and serum biochemistry with no values suspicious for liver pathology or potentially indicative of E. multilocularis infection. This correlated well with ultrasound, laparoscopy, and immunoblotting, which were unremarkable in these individuals. Two wild Bavarian individuals were suspected E. multilocularis positive at post-mortem, through the presence of hepatic cysts. Sensitivity and specificity of a combination of laparoscopy and abdominal ultrasonography in the detection of parasitic liver cyst lesions was 100% in the subset of cadavers (95%Confidence Intervals 34.24–100%, and 86.7–100% respectively). For abdominal ultrasonography alone sensitivity was only 50% (95%CI 9.5–90.6%), with specificity being 100% (95%CI 79.2–100%). For laparoscopy alone sensitivity was 100% (95% CI 34.2–100%), with specificity also being 100% (95% CI 77.2–100%). Further immunoblotting, PCR and histopathological examination revealed one individual positive for E. multilocularis, whilst the other individual was positive for Taenia martis. PMID:26167927

Substrate-Driven Convergence of the Microbial Community in Lignocellulose-Amended Enrichments of Gut Microflora from the Canadian Beaver (Castor canadensis) and North American Moose (Alces americanus).

PubMed

Wong, Mabel T; Wang, Weijun; Lacourt, Michael; Couturier, Marie; Edwards, Elizabeth A; Master, Emma R

2016-01-01

Strategic enrichment of microcosms derived from wood foragers can facilitate the discovery of key microbes that produce enzymes for the bioconversion of plant fiber (i.e., lignocellulose) into valuable chemicals and energy. In this study, lignocellulose-degrading microorganisms from the digestive systems of Canadian beaver (Castor canadensis) and North American moose (Alces americanus) were enriched under methanogenic conditions for over 3 years using various wood-derived substrates, including (i) cellulose (C), (ii) cellulose + lignosulphonate (CL), (iii) cellulose + tannic acid (CT), and (iv) poplar hydrolysate (PH). Substantial improvement in the conversion of amended organic substrates into biogas was observed in both beaver dropping and moose rumen enrichment cultures over the enrichment phases (up to 0.36-0.68 ml biogas/mg COD added), except for enrichments amended with tannic acid where conversion was approximately 0.15 ml biogas/mg COD added. Multiplex-pyrosequencing of 16S rRNA genes revealed systematic shifts in the population of Firmicutes, Bacteroidetes, Chlorobi, Spirochaetes, Chloroflexi, and Elusimicrobia in response to the enrichment. These shifts were predominantly substrate driven, not inoculum driven, as revealed by both UPGMA clustering pattern and OTU distribution. Additionally, the relative abundance of multiple OTUs from poorly defined taxonomic lineages increased from less than 1% to 25-50% in microcosms amended with lignocellulosic substrates, including OTUs from classes SJA-28, Endomicrobia, orders Bacteroidales, OPB54, and family Lachnospiraceae. This study provides the first direct comparison of shifts in microbial communities that occurred in different environmental samples in response to multiple relevant lignocellulosic carbon sources, and demonstrates the potential of enrichment to increase the abundance of key lignocellulolytic microorganisms and encoded activities.

Substrate-Driven Convergence of the Microbial Community in Lignocellulose-Amended Enrichments of Gut Microflora from the Canadian Beaver (Castor canadensis) and North American Moose (Alces americanus)

PubMed Central

Wong, Mabel T.; Wang, Weijun; Lacourt, Michael; Couturier, Marie; Edwards, Elizabeth A.; Master, Emma R.

2016-01-01

Strategic enrichment of microcosms derived from wood foragers can facilitate the discovery of key microbes that produce enzymes for the bioconversion of plant fiber (i.e., lignocellulose) into valuable chemicals and energy. In this study, lignocellulose-degrading microorganisms from the digestive systems of Canadian beaver (Castor canadensis) and North American moose (Alces americanus) were enriched under methanogenic conditions for over 3 years using various wood-derived substrates, including (i) cellulose (C), (ii) cellulose + lignosulphonate (CL), (iii) cellulose + tannic acid (CT), and (iv) poplar hydrolysate (PH). Substantial improvement in the conversion of amended organic substrates into biogas was observed in both beaver dropping and moose rumen enrichment cultures over the enrichment phases (up to 0.36–0.68 ml biogas/mg COD added), except for enrichments amended with tannic acid where conversion was approximately 0.15 ml biogas/mg COD added. Multiplex-pyrosequencing of 16S rRNA genes revealed systematic shifts in the population of Firmicutes, Bacteroidetes, Chlorobi, Spirochaetes, Chloroflexi, and Elusimicrobia in response to the enrichment. These shifts were predominantly substrate driven, not inoculum driven, as revealed by both UPGMA clustering pattern and OTU distribution. Additionally, the relative abundance of multiple OTUs from poorly defined taxonomic lineages increased from less than 1% to 25–50% in microcosms amended with lignocellulosic substrates, including OTUs from classes SJA-28, Endomicrobia, orders Bacteroidales, OPB54, and family Lachnospiraceae. This study provides the first direct comparison of shifts in microbial communities that occurred in different environmental samples in response to multiple relevant lignocellulosic carbon sources, and demonstrates the potential of enrichment to increase the abundance of key lignocellulolytic microorganisms and encoded activities. PMID:27446004

Topics on distance correlation, feature screening and lifetime expectancy with application to Beaver Dam eye study data

NASA Astrophysics Data System (ADS)

Kong, Jing

This thesis includes 4 pieces of work. In Chapter 1, we present the work with a method for examining mortality as it is seen to run in families, and lifestyle factors that are also seen to run in families, in a subpopulation of the Beaver Dam Eye Study that has died by 2011. We find significant distance correlations between death ages, lifestyle factors, and family relationships. Considering only sib pairs compared to unrelated persons, distance correlation between siblings and mortality is, not surprisingly, stronger than that between more distantly related family members and mortality. Chapter 2 introduces a feature screening procedure with the use of distance correlation and covariance. We demonstrate a property for distance covariance, which is incorporated in a novel feature screening procedure based on distance correlation as a stopping criterion. The approach is further implemented to two real examples, namely the famous small round blue cell tumors data and the Cancer Genome Atlas ovarian cancer data Chapter 3 pays attention to the right censored human longevity data and the estimation of lifetime expectancy. We propose a general framework of backward multiple imputation for estimating the conditional lifetime expectancy function and the variance of the estimator in the right censoring setting and prove the properties of the estimator. In addition, we apply the method to the Beaver Dam eye study data to study human longevity, where the expected human lifetime are modeled with smoothing spline ANOVA based on the covariates including baseline age, gender, lifestyle factors and disease variables. Chapter 4 compares two imputation methods for right censored data, namely the famous Buckley-James estimator and the backward imputation method proposed in Chapter 3 and shows that backward imputation method is less biased and more robust with heterogeneity.

Do transmitters affect survival and body condition of American beavers Castor canadensis?

USGS Publications Warehouse

Smith, Joshua B.; Windels, Steve K.; Wolf, Tiffany; Klaver, Robert W.; Belant, Jerrold L.

2016-01-01

One key assumption often inferred with using radio-equipped individuals is that the transmitter has no effect on the metric of interest. To evaluate this assumption, we used a known fate model to assess the effect of transmitter type (i.e. tail-mounted or peritoneal implant) on short-term (one year) survival and a joint live—dead recovery model and results from a mark—recapture study to compare long-term (eight years) survival and body condition of ear-tagged only American beavers Castor canadensis to those equipped with radio transmitters in Voyageurs National Park, Minnesota, USA. Short-term (1-year) survival was not influenced by transmitter type (wi = 0.64). Over the 8-year study period, annual survival was similar between transmitter-equipped beavers (tail-mounted and implant transmitters combined; 0.76; 95% CI = 0.45–0.91) versus ear-tagged only (0.78; 95% CI = 0.45–0.93). Additionally, we found no difference in weight gain (t9 = 0.25, p = 0.80) or tail area (t11 = 1.25, p = 0.24) from spring to summer between the two groups. In contrast, winter weight loss (t22 = - 2.03, p = 0.05) and tail area decrease (t30 = - 3.04, p = 0.01) was greater for transmitterequipped (weight = - 3.09 kg, SE = 0.55; tail area = - 33.71 cm2, SE = 4.80) than ear-tagged only (weight = - 1.80 kg, SE = 0.33; tail area = - 12.38 cm2, SE = 5.13) beavers. Our results generally support the continued use of transmitters on beavers for estimating demographic parameters, although we recommend additional assessments of transmitter effects under different environmental conditions.

Carbon trace gases in lake and beaver pond ice near Thompson, Manitoba, Canada

NASA Astrophysics Data System (ADS)

Kuhlbusch, Thomas A. J.; Zepp, Richard G.

1999-11-01

Concentrations of CO2, CO, and CH4 were measured in beaver pond and lake ice in April 1996 near Thompson, Manitoba to derive information on possible impacts of ice melting on corresponding atmospheric trace gas concentrations. CH4 concentrations in beaver pond and lake ice ranged between 0.3-150 mmol m-3 and 3.1-56.2 μmol m-3, respectively. The corresponding CO concentrations showed no significant differences between the two lakes. They varied between 50 and 250 μmol m-3. These CO concentrations are some of the highest determined in any aquatic system. The differences in CH4 concentrations between lake and pond can be explained by the differences in production and microbial oxidation rates between the two systems. No explanation can be given for the similar CO concentrations. Supersaturation factors for CO were 660±130 and 630±330, and 65-35000 and 0.6-13 for CH4 in the ice of the beaver pond and Troy Lake, respectively. When digging into the beaver pond ice, a continuous flow of bubbles with 0.32±0.06 vol% CH4, 2.2±0.3 vol% CO2, and 482±98 ppb CO coming out of the slash ice for about 20-30 minutes was noticed. Wintertime flux estimates of CH4 and CO showed that they represent at minimum 6.4% and 2.2% of that of the summer. It has to be noted that these wintertime fluxes will mostly be released to the atmosphere during the time of snowmelt, thus a limited time period of weeks.

Elk browsing increases aboveground growth of water-stressed willows by modifying plant architecture.

PubMed

Johnston, Danielle B; Cooper, David J; Hobbs, N Thompson

2007-12-01

In the northern elk wintering range of Yellowstone National Park, USA, wolf (Canis lupus) removal allowed elk (Cervus elaphus) to overbrowse riparian woody plants, leading to the exclusion of beaver (Castor canadensis) and a subsequent water table decline in many small stream valleys. Reduced elk browsing following wolf reintroduction may or may not facilitate willow (Salix sp.) recovery in these areas. To determine if the effect of elk browsing on willow interacts with that of beaver abandonment, we manipulated elk browsing and the water table in a factorial experiment. Under the condition of an ambient (low) water table, elk browsing increased shoot water potential (Psis), photosynthesis per unit leaf area (A), stomatal conductance per unit leaf area (gs), and aboveground current annual growth (CAG) by 50%. Elk browsing occurred entirely during dormancy and did not affect total plant leaf area (L). Improved water balance, photosynthetic rate, and annual aboveground productivity in browsed willows appeared to be due to morphological changes, such as increased shoot diameter and decreased branching, which typically increase plant hydraulic conductivity. An elevated water table increased Psis, A, gs, CAG, and L, and eliminated or lessened the positive effect of browsing on CAG for most species. Because low water tables create conditions whereby high willow productivity depends on the morphological effects of annual elk browsing, removing elk browsing in areas of water table decline is unlikely to result in vigorous willow stands. As large willow standing crops are required by beaver, a positive feedback between water-stressed willow and beaver absence may preclude the reestablishment of historical conditions. In areas with low water table, willow restoration may depend on actions to promote the re-establishment of beaver in addition to reducing elk browsing.

Wolfhounds and Polar Bears in Siberia: America’s Military Intervention, 1918-1920

DTIC Science & Technology

1986-01-01

including sable, sea otter, otter, beaver, mink, muskrat, squirrel, fox, skunk, woodchuck, marmot , badger, glutton, and rabbit. Vast forests provided wood for...venti- lated, heated, and lighted. A kitchen was found on the end of each floor in the barracks. Latrines drained into open cesspools. Wood burning

Habitat Is Where It's At. A Coloring Book about Wildlife Habitat.

ERIC Educational Resources Information Center

Hernbrode, Bob

This coloring book provides illustrations of 18 animals in their habitats. Animals presented include: beavers; bears; bats; housecats; elephants; moose; tigers; geese; chimpanzees; rabbits; butterflies; giraffes; fish; kangaroos; gnus; bugs and bees; and humans. Two additional illustrations are provided which show that the sun and air are part of…

Environmental Protection Begins with You: A Guide to Environmental Community Service

ERIC Educational Resources Information Center

US Environmental Protection Agency, 2006

2006-01-01

This guide contains examples of volunteer projects related to solid waste management. Volunteering provides the opportunity to enjoy new experiences, meet new people, learn new skills, and put ideas and talents to work. The stories included in this guide are: (1) Raucous Revelry and Recycling: Penn State Beaver Stadium Post-Game Recycling…

Environmental Assessment for Watershed Enhancements at Joint Base Elmendorf-Richardson

DTIC Science & Technology

2013-07-03

Potassium permanganate would be utilized to prevent lethal dose of rotenone migrating beyond the largest beaver dam on Otter Creek. Lowering the lake level...Finding of No Significant Impact JBER Joint Base Elmendorf-Richardson KMnO4 potassium permanganate MOA Municipality of Anchorage NEPA National...Potassium permanganate would be utilized to prevent lethal dose of rotenone migrating beyond the largest beaver dam on Otter Creek. Lowering the lake

An 11 000-year-long record of fire and vegetation history at Beaver Lake, Oregon, central Willamette Valley

Treesearch

Megan K. Walsh; Christopher A. Pearl; Cathy Whitlock; Patrick J. Bartlein; Marc A. Worona

2010-01-01

High-resolution macroscopic charcoal and pollen analysis were used to reconstruct an 11 000-year-long record of fire and vegetation history from Beaver Lake, Oregon, the first complete Holocene paleoecological record from the floor of the Willamette Valley. In the early Holocene (ca 11 000-7500 calendar years before present [cal yr BP]), warmer, drier summers than at...

High rates of energy expenditure and water flux in free-ranging Point Reyes mountain beavers Aplodontia rufa phaea

USGS Publications Warehouse

Crocker, D.E.; Kofahl, N.; Fellers, G.D.; Gates, N.B.; Houser, D.S.

2007-01-01

We measured water flux and energy expenditure in free-ranging Point Reyes mountain beavers Aplodontia rufa phaea by using the doubly labeled water method. Previous laboratory investigations have suggested weak urinary concentrating ability, high rates of water flux, and low basal metabolic rates in this species. However, free-ranging measurements from hygric mammals are rare, and it is not known how these features interact in the environment. Rates of water flux (210 ?? 32 mL d-1) and field metabolic rates (1,488 ?? 486 kJ d-1) were 159% and 265%, respectively, of values predicted by allometric equations for similar-sized herbivores. Mountain beavers can likely meet their water needs through metabolic water production and preformed water in food and thus remain in water balance without access to free water. Arginine-vasopressin levels were strongly correlated with rates of water flux and plasma urea : creatinine ratios, suggesting an important role for this hormone in regulating urinary water loss in mountain beavers. High field metabolic rates may result from cool burrow temperatures that are well below lower critical temperatures measured in previous laboratory studies and suggest that thermoregulation costs may strongly influence field energetics and water flux in semifossorial mammals. ?? 2007 by The University of Chicago. All rights reserved.

Hydrologic Change during the Colonial Era of the United States: Beavers and the Energy Cost of Impoundments (Invited)

NASA Astrophysics Data System (ADS)

Green, M. B.; Bain, D. J.; Arrigo, J. S.; Duncan, J. M.; Kumar, S.; Parolari, A.; Salant, N.; Vorosmarty, C. J.; Aloysius, N. R.; Bray, E. N.; Ruffing, C. M.; Witherell, B. B.

2009-12-01

Europeans colonized North America in the early 17th century with intentions ranging between long-term inhabitation and quick extraction of resources for economic gain in Europe. Whatever the intentions, the colonists relied on the landscape for resources resulting in dramatic change to the forest and fur-bearing mammal population. We demonstrate that initial exploitation of North American forest and furs caused a substantial decrease in mean water residence time (τ) between 1600 and 1800 A.D. That loss, which regionally changed from 51 to 41 days, contrasts with conventional wisdom that humans tend to diminish variability in water resources by increasing storage capacity and thus increasing τ. The loss of τ resulted from over-hunted beaver for the hat market in Europe. Analysis suggests that colonial era demographics and economics did not allow human resource allocation to impoundment construction on a level matching the historic beaver effort. However, the τ appears to have regionally increased during the 19th century, suggesting that humans eventually began replacing the water storage lost with the beaver. The analysis highlights the energy cost of impounding water, which is likely to continue to be an important factor given the increasing need for stable water resources and finite energy resources.

Methow River Studies, Washington: abundance estimates from Beaver Creek and the Chewuch River screw trap, methodology testing in the Whitefish Island side channel, and survival and detection estimates from hatchery fish releases, 2013

USGS Publications Warehouse

Martens, Kyle D.; Fish, Teresa M.; Watson, Grace A.; Connolly, Patrick J.

2014-01-01

Salmon and steelhead populations have been severely depleted in the Columbia River from factors such as the presence of tributary dams, unscreened irrigation diversions, and habitat degradation from logging, mining, grazing, and others (Raymond, 1988). The U.S. Geological Survey (USGS) has been funded by the Bureau of Reclamation (Reclamation) to provide evaluation of on-going Reclamation funded efforts to recover Endangered Species Act (ESA) listed anadromous salmonid populations in the Methow River watershed, a watershed of the Columbia River in the Upper Columbia River Basin, in north-central Washington State (fig. 1). This monitoring and evaluation program was funded to document Reclamation’s effort to partially fulfill the 2008 Federal Columbia River Power System Biological Opinion (BiOp) (National Oceanographic and Atmospheric Administration, Fisheries Division 2003). This Biological Opinion includes Reasonable and Prudent Alternatives (RPA) to protect listed salmon and steelhead across their life cycle. Species of concern in the Methow River include Upper Columbia River (UCR) spring Chinook salmon (Oncorhynchus tshawytscha), UCR summer steelhead (O. mykiss), and bull trout (Salvelinus confluentus), which are all listed as threatened or endangered under the ESA. The work done by the USGS since 2004 has encompassed three phases of work. The first phase started in 2004 and continued through 2012. This first phase involved the evaluation of stream colonization and fish production in Beaver Creek following the modification of several water diversions (2000–2006) that were acting as barriers to upstream fish movement. Products to date from this work include: Ruttenburg (2007), Connolly and others (2008), Martens and Connolly (2008), Connolly (2010), Connolly and others (2010), Martens and Connolly (2010), Benjamin and others (2012), Romine and others (2013a), Weigel and others (2013a, 2013b, 2013c), and Martens and others (2014). The second phase, initiated in 2008, focuses on the evaluation of the M2 reach (rkm 66– 80) of the mainstem Methow River prior to restoration actions planned by Reclamation and Yakama Nation. The M2 study was designed to help understand the inter-relationships between stream habitat and the life history of various fish species to explain potential success or limitations in response to restoration actions. To help document changes derived by restoration, two reference reaches (Upper Methow between rkm 85 and 90, and Chewuch River between rkm 4 and 11) were identified based on relative lack of disturbance, proximity to the restoration reach, and relative unconfined geomorphology. A control reach (Lower Methow between rkm 57 and 64, also referred to as “Silver Reach”) was 2 identified based on its similar disturbance as the reference reach, proximity to the restoration reach, and relatively unconfined geomorphology. Products to date include Barber and others (2011), Bellmore (2011), Tibbits and others (2012), Bellmore and others (2013), Benjamin and others (2013), Romine and others (2013b), Bellmore and other (2014), Martens and others (2014), and Martens and Connolly (2014). The third phase of work has been to help with the development and to provide data for modeling efforts. Most of the planned M2 reach restoration is focused on the creation or improvement of offchannel habitat, especially side channels. The pre-restoration portion of this study has been documented by Martens and Connolly (2014). Side channel restoration actions were initiated in 2012 (Whitefish Island side channel, also referred to as SC3; rkm 76) and are planned to continue over the next several years. The Whitefish Island side channel was modified to maintain hydrological connection with the mainstem throughout the year. In addition, several log structures were installed and pools were deepened to create fish habitat. Prior to restoration, this side channel would lose hydrological connection with the mainstem Methow River, leaving one large pool near the bottom of the side channel and several shallow isolated pools that may or may not go dry. In seasonally connected side channels, juvenile salmonid survival in pools less than 100 cm average depth was lower than in pools greater than 100 cm average depth (Martens and Connolly, 2014). In this report, we document our field work and analysis completed in 2013. During 2013, USGS sampling efforts were focused on resampling of three reaches in Beaver Creek, testing methodology in the Whitefish Island side channel, conducting hatchery survival estimates, and operating a screw trap on the Chewuch River (funded by Yakama Nation; fig. 1). The Beaver Creek sampling effort was a revisit of three index sites sampled continuously from 2004 to 2007 to look at the fish response to barrier removal. Methodology testing in Whitefish Island side channel was done to determine the best method for evaluating fish populations after restoration efforts in side channels (previous sampling methods were determined to be ineffective after pools were deepened). Hatchery survival estimates were completed to monitor fish survival in the Methow and Columbia Rivers, while the screw trap was operated to estimate migrating fish populations in the Chewuch River and track passive integrated transponder (PIT)-tagged fish. In addition, we maintained a network of PIT-tag interrogation systems (PTIS), assisted Reclamation with fish removal events associated with stream restoration (two people for 9 days; 14 percent of summer field season), and conducted a stream metabolism study designed to help parameterize and calibrate the stream productivity model (Bellmore and others, 2014) with model validation.

Light and Electron Microscopy of the European Beaver (Castor fiber) Stomach Reveal Unique Morphological Features with Possible General Biological Significance

PubMed Central

Petryński, Wojciech; Palkowska, Katarzyna; Prusik, Magdalena; Targońska, Krystyna; Giżejewski, Zygmunt; Przybylska-Gornowicz, Barbara

2014-01-01

Anatomical, histological, and ultrastructural studies of the European beaver stomach revealed several unique morphological features. The prominent attribute of its gross morphology was the cardiogastric gland (CGG), located near the oesophageal entrance. Light microscopy showed that the CGG was formed by invaginations of the mucosa into the submucosa, which contained densely packed proper gastric glands comprised primarily of parietal and chief cells. Mucous neck cells represented <0.1% of cells in the CGG gastric glands and 22–32% of cells in the proper gastric glands of the mucosa lining the stomach lumen. These data suggest that chief cells in the CGG develop from undifferentiated cells that migrate through the gastric gland neck rather than from mucous neck cells. Classical chief cell formation (i.e., arising from mucous neck cells) occurred in the mucosa lining the stomach lumen, however. The muscularis around the CGG consisted primarily of skeletal muscle tissue. The cardiac region was rudimentary while the fundus/corpus and pyloric regions were equally developed. Another unusual feature of the beaver stomach was the presence of specific mucus with a thickness up to 950 µm (in frozen, unfixed sections) that coated the mucosa. Our observations suggest that the formation of this mucus is complex and includes the secretory granule accumulation in the cytoplasm of pit cells, the granule aggregation inside cells, and the incorporation of degenerating cells into the mucus. PMID:24727802

Effects of acidic precipitation on waterbirds in Maine

USGS Publications Warehouse

Longcore, J.R.; McAuley, D.G.; Stromborg, K.L.; Hensler, G.L.

1985-01-01

During 1982-84 waterbird use and numbers of waterbird broods were recorded for 29 wetlands on two study areas (25 and 77 km2) in east-central Maine underlain with bedrock having low, acid-neutralizing capacity (ANC). Twenty-nine wetlands over bedrock with high ANC (Class 3) and 31 wetlands over bedrock of low ANC (Class 1) were evaluated as predictors of wetland pH and alkalinity. Using the alkalinity value of 25 times was greater (P< ..0001) for downstream (84%) versus headwater (16%) wetlands during 1982-84. Avian use was similar when wetlands were classified either as beaver-created or glacial in origin. Headwater wetlands, which are most vulnerable to acidification within the low ANC areas, are used mostly by common goldeneye (Bucephala clangula), and common loon (Gavia immer). Common merganser (Mergus merganser), spotted sandpiper (Actitis macularia), and chimney swift (Chaetura pelagica) were associated with headwater wetlands about equally. The majority of species (16), including dabbling ducks, used, almost exclusively, wetlands classified as downstream or beaver-created. For all years, 87% of the 246 broods observed was on wetlands classified as either downstream or beaver-created. Our data suggest that avian use of wetlands is influenced more by the morphometric and vegetative characteristics of the wetland basin rather than by the wetland water chemistry. Nevertheless, large numbers of a variety of avian species are associated with wetlands underlain with bedrock that has little or no capacity to neutralize acidic depositions.

Influences of herbivory and water on willow in elk winter range

USGS Publications Warehouse

Zeigenfuss, L.C.; Singer, F.J.; Williams, S.A.; Johnson, T.L.

2002-01-01

Elimination of large predators and reduced hunter harvest have led to concerns that an increasing elk (Cervus elaphus) population may be adversely affecting vegetation on the low-elevation elk winter range of Rocky Mountain National Park, Colorado, USA. Beaver (Castor canadensis) and their impoundments also have declined dramatically (94%) in the same area over the past 50 years coincident with a 20% decline in willow (Salix spp.) cover. From 1994 to 1998, we studied vegetation production responses of willow communities to elk herbivory and water availability. We estimated willow production by measuring current annual growth of shrubs in 9.3-m2 circular plots, and we measured herbaceous production by clipping vegetation within 0.25-m2 circular plots. Elk herbivory suppressed willow heights, leader lengths, annual production, and herbaceous productivity of willow communities. Water impoundment had a positive effect on herbaceous plant production, but little effect on shrubs, possibly because water tables were naturally high on the study sites even without beaver dams. Nevertheless, the winter range environment previously included more riparian willow habitat because of more stream area (47-69%) due to larger beaver populations. Elk herbivory appears to be the dominant force determining vegetation productivity in willow sites, but the effects may be exacerbated by lowered water tables. Fewer elk or protection from browsing, and water enhancement for <10 years along with management to encourage elk movement away from willow communities, could possibly work as strategies to reestablish sustainable willow communities.

Protecting the Homeland: The Importance of Counter-Illicit Trafficking to Prevent an Attack with Weapons of Mass Destruction

DTIC Science & Technology

2013-03-01

Congressional Research Service, U.S. International Borders: Brief Facts, Janice Cheryl Beaver , RS21729 (Washington, DC: Government Printing Office, November 9...and the opportunity to utilize the breadth of smuggling options for transportation. The commercial prevalence of radiological material and the...Janice Cheryl Beaver . RS21729. Washington, DC: Government Printing Office November 9, 2006. http://www.fas.org/sgp/crs/misc/RS21729.pdf (accessed

The influence of fall-spawning coho salmon (Oncorhynchus kisutch) on growth and production of juvenile coho salmon rearing in beaver ponds on the Copper River Delta, Alaska.

Treesearch

Dirk W. Lang; Gordon H. Reeves; James D. Hall; Mark S. Wipfli

2006-01-01

This study examined the influence of fall-spawning coho salmon (Oncorhynchrcs kisutch) on the density, growth rate, body condition, and survival to outmigration of juvenile coho salmon on the Copper River Delta, Alaska, USA. During the fall of 1999 and 2000, fish rearing in beaver ponds that received spawning salmon were compared with fish from...

Harvesting of males delays female breeding in a socially monogamous mammal; the beaver.

PubMed

Parker, Howard; Rosell, Frank; Mysterud, Atle

2007-02-22

Human exploitation may skew adult sex ratios in vertebrate populations to the extent that males become limiting for normal reproduction. In polygynous ungulates, females delay breeding in heavily harvested populations, but effects are often fairly small. We would expect a stronger effect of male harvesting in species with a monogamous mating system, but no such study has been performed. We analysed the effect of harvesting males on the timing of reproduction in the obligate monogamous beaver (Castor fiber). We found a negative impact of harvesting of adult males on the timing of parturition in female beavers. The proportion of normal breeders sank from over 80%, when no males had been shot in the territories of pregnant females, to under 20%, when three males had been shot. Harvesting of males in monogamous mammals can apparently affect their normal reproductive cycle.

Did "The Beaver" Question My Authority? Helping Children Learn about Respect

ERIC Educational Resources Information Center

Meidl, Christopher; Meidl, Tynisha

2009-01-01

In trying to make sense of how to navigate the duality of approaches to how children learn respect toward others--the "takes a village" community-oriented approach (that includes teachers) or the "I know my child best/go it alone" family autonomy approach--teachers need to understand that families are trying to navigate "parenting" their children…

75 FR 25876 - Notice of Intent To Prepare Resource Management Plans for the Beaver Dam Wash and Red Cliffs...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-10

... personnel; Federal, state, and local agencies; and other stakeholders. The issues include: Air quality... of the Sand Mountain Special Recreation Management Area will remain Open under all alternatives of the plan amendment, consistent with the agreement for joint management by the State of Utah's Sand...

Geochemical map of the Wet Beaver Roadless Area, Coconino and Yavapai counties, Arizona

USGS Publications Warehouse

Gerstel, W.J.

1985-01-01

The geochemical survey of the Wet Beaver Roadless Area was conducted in May 1982 by the U.S. Geological Survey to aid in a mineral resource appraisal of the area. A total of 64 stream-sediment samples, 30 heavy-mineral concentrates from stream sediment, 7 rock samples, and 7 water samples was collected by S.C. Rose, D.E. Hendzel, and W.J. Gerstel, with helicopter support from Jack Ruby, pilot for Helicopters Unlimited.

Defense AR Journal, Volume 15, Number 1, April 2008

DTIC Science & Technology

2008-04-01

Beavers William Ruta DAUAA Research Paper Competition: 3rd Place Employing Organizational Modeling & Simulation of the KC-135 Depot’s Flight Controls Maj...AttAck munition SYStemS (jAmS) Project office imProvinG SuPPort to the wArfiGhter Barry Beavers and William Ruta The Joint Attack Munition Systems...William Ruta . This paper examines how the JAMS Project Office improved support to the warfighter with its implementation of the Life Cycle

Wood and Sediment Dynamics in River Corridors

NASA Astrophysics Data System (ADS)

Wohl, E.; Scott, D.

2015-12-01

Large wood along rivers influences entrainment, transport, and storage of mineral sediment and particulate organic matter. We review how wood alters sediment dynamics and explore patterns among volumes of instream wood, sediment storage, and residual pools for dispersed pieces of wood, logjams, and beaver dams. We hypothesized that: volume of sediment per unit area of channel stored in association with wood is inversely proportional to drainage area; the form of sediment storage changes downstream; sediment storage correlates most strongly with wood load; and volume of sediment stored behind beaver dams correlates with pond area. Lack of data from larger drainage areas limits tests of these hypotheses, but analyses suggest a negative correlation between sediment volume and drainage area and a positive correlation between wood and sediment volume. The form of sediment storage in relation to wood changes downstream, with wedges of sediment upstream from jammed steps most prevalent in small, steep channels and more dispersed sediment storage in lower gradient channels. Use of a published relation between sediment volume, channel width, and gradient predicted about half of the variation in sediment stored upstream from jammed steps. Sediment volume correlates well with beaver pond area. Historically more abundant instream wood and beaver populations likely equated to greater sediment storage within river corridors. This review of the existing literature on wood and sediment dynamics highlights the lack of studies on larger rivers.

Water-Quality and Biological Characteristics and Responses to Agricultural Land Retirement in Three Streams of the Minnesota River Basin, Water Years 2006-08

USGS Publications Warehouse

Christensen, Victoria G.; Lee, Kathy E.; Sanocki, Christopher A.; Mohring, Eric H.; Kiesling, Richard L.

2009-01-01

Water-quality and biological characteristics in three streams in the Minnesota River Basin were assessed using data collected during water years 2006-08. The responses of nutrient concentrations, suspended-sediment concentrations, and biological characteristics to agricultural land retirement also were assessed. In general, total nitrogen, suspended-sediment, and chlorophyll-a concentrations, and fish resource quality improved with increasing land retirement. The Chetomba Creek, West Fork Beaver Creek, and South Branch Rush River subbasins, which range in size from about 200 to 400 square kilometers, have similar geologic and hydrologic settings but differ with respect to the amount, type, and location of retired agricultural land. Total nitrogen concentrations were largest, with a mean of 15.0 milligrams per liter (mg/L), in water samples from the South Branch Rush River, a subbasin with little to no agricultural land retirement; total nitrogen concentrations were smaller in samples from Chetomba Creek (mean of 10.6 mg/L) and West Fork Beaver Creek (mean of 7.9 mg/L), which are subbasins with more riparian or upland land retirement at the basin scale. Total phosphorus concentrations were not related directly to differing land-retirement percentages with mean concentrations at primary data-collection sites of 0.259 mg/L in the West Fork Beaver Creek subbasin, 0.164 mg/L in the Chetomba Creek subbasin, and 0.180 mg/L in the South Branch Rush River subbasin. Temporal variation in water quality was characterized using data from in-stream water-quality monitors and storm-sediment data. Fish data indicate better resource quality for the West Fork Beaver Creek subbasin than for other subbasins likely due to a combination of factors, including habitat quality, food resources, and dissolved oxygen characteristics. Index of biotic integrity (IBI) scores increased as local land-retirement percentages (within 50 and 100 meters of the streams) increased. Data and analysis from this study can be used to evaluate the success of agricultural management practices and land-retirement programs for improving stream quality.

Persistence at distributional edges: Columbia spotted frog habitat in the arid Great Basin, USA

PubMed Central

Arkle, Robert S; Pilliod, David S

2015-01-01

A common challenge in the conservation of broadly distributed, yet imperiled species is understanding which factors facilitate persistence at distributional edges, locations where populations are often vulnerable to extirpation due to changes in climate, land use, or distributions of other species. For Columbia spotted frogs (Rana luteiventris) in the Great Basin (USA), a genetically distinct population segment of conservation concern, we approached this problem by examining (1) landscape-scale habitat availability and distribution, (2) water body-scale habitat associations, and (3) resource management-identified threats to persistence. We found that areas with perennial aquatic habitat and suitable climate are extremely limited in the southern portion of the species’ range. Within these suitable areas, native and non-native predators (trout and American bullfrogs [Lithobates catesbeianus]) are widespread and may further limit habitat availability in upper- and lower-elevation areas, respectively. At the water body scale, spotted frog occupancy was associated with deeper sites containing abundant emergent vegetation and nontrout fish species. Streams with American beaver (Castor canadensis) frequently had these structural characteristics and were significantly more likely to be occupied than ponds, lakes, streams without beaver, or streams with inactive beaver ponds, highlighting the importance of active manipulation of stream environments by beaver. Native and non-native trout reduced the likelihood of spotted frog occupancy, especially where emergent vegetation cover was sparse. Intensive livestock grazing, low aquatic connectivity, and ephemeral hydroperiods were also negatively associated with spotted frog occupancy. We conclude that persistence of this species at the arid end of its range has been largely facilitated by habitat stability (i.e., permanent hydroperiod), connectivity, predator-free refugia, and a commensalistic interaction with an ecosystem engineer. Beaver-induced changes to habitat quality, stability, and connectivity may increase spotted frog population resistance and resilience to seasonal drought, grazing, non-native predators, and climate change, factors which threaten local or regional persistence. PMID:26380699

Persistence at distributional edges: Columbia spotted frog habitat in the arid Great Basin, USA.

PubMed

Arkle, Robert S; Pilliod, David S

2015-09-01

A common challenge in the conservation of broadly distributed, yet imperiled species is understanding which factors facilitate persistence at distributional edges, locations where populations are often vulnerable to extirpation due to changes in climate, land use, or distributions of other species. For Columbia spotted frogs (Rana luteiventris) in the Great Basin (USA), a genetically distinct population segment of conservation concern, we approached this problem by examining (1) landscape-scale habitat availability and distribution, (2) water body-scale habitat associations, and (3) resource management-identified threats to persistence. We found that areas with perennial aquatic habitat and suitable climate are extremely limited in the southern portion of the species' range. Within these suitable areas, native and non-native predators (trout and American bullfrogs [Lithobates catesbeianus]) are widespread and may further limit habitat availability in upper- and lower-elevation areas, respectively. At the water body scale, spotted frog occupancy was associated with deeper sites containing abundant emergent vegetation and nontrout fish species. Streams with American beaver (Castor canadensis) frequently had these structural characteristics and were significantly more likely to be occupied than ponds, lakes, streams without beaver, or streams with inactive beaver ponds, highlighting the importance of active manipulation of stream environments by beaver. Native and non-native trout reduced the likelihood of spotted frog occupancy, especially where emergent vegetation cover was sparse. Intensive livestock grazing, low aquatic connectivity, and ephemeral hydroperiods were also negatively associated with spotted frog occupancy. We conclude that persistence of this species at the arid end of its range has been largely facilitated by habitat stability (i.e., permanent hydroperiod), connectivity, predator-free refugia, and a commensalistic interaction with an ecosystem engineer. Beaver-induced changes to habitat quality, stability, and connectivity may increase spotted frog population resistance and resilience to seasonal drought, grazing, non-native predators, and climate change, factors which threaten local or regional persistence.

Persistence at distributional edges: Columbia spotted frog habitat in the arid Great Basin, USA

USGS Publications Warehouse

Arkle, Robert S.; Pilliod, David S.

2015-01-01

A common challenge in the conservation of broadly distributed, yet imperiled species is understanding which factors facilitate persistence at distributional edges, locations where populations are often vulnerable to extirpation due to changes in climate, land use, or distributions of other species. For Columbia spotted frogs (Rana luteiventris) in the Great Basin (USA), a genetically distinct population segment of conservation concern, we approached this problem by examining (1) landscape-scale habitat availability and distribution, (2) water body-scale habitat associations, and (3) resource management-identified threats to persistence. We found that areas with perennial aquatic habitat and suitable climate are extremely limited in the southern portion of the species’ range. Within these suitable areas, native and non-native predators (trout and American bullfrogs [Lithobates catesbeianus]) are widespread and may further limit habitat availability in upper- and lower-elevation areas, respectively. At the water body scale, spotted frog occupancy was associated with deeper sites containing abundant emergent vegetation and nontrout fish species. Streams with American beaver (Castor canadensis) frequently had these structural characteristics and were significantly more likely to be occupied than ponds, lakes, streams without beaver, or streams with inactive beaver ponds, highlighting the importance of active manipulation of stream environments by beaver. Native and non-native trout reduced the likelihood of spotted frog occupancy, especially where emergent vegetation cover was sparse. Intensive livestock grazing, low aquatic connectivity, and ephemeral hydroperiods were also negatively associated with spotted frog occupancy. We conclude that persistence of this species at the arid end of its range has been largely facilitated by habitat stability (i.e., permanent hydroperiod), connectivity, predator-free refugia, and a commensalistic interaction with an ecosystem engineer. Beaver-induced changes to habitat quality, stability, and connectivity may increase spotted frog population resistance and resilience to seasonal drought, grazing, non-native predators, and climate change, factors which threaten local or regional persistence.

Testing and Evaluation of Archeological Sites 32ML404 and 32ML406 in McLean County, North Dakota.

DTIC Science & Technology

1978-09-01

region include aggregating ( herd ) animals as well as those that are dispersed. The most important animal to prehistoric inhabitants of the area was the...bison which is a herd animal and served as a primary faunal resource. Important fauna that do not aggregate include deer, elk, antelope and dog. Other...fauna in the area include rabbit, squirrel, prairie dog, badger, beaver, bobcat, coyote, fox, porcupine , skunk, vole, and wolf (Zimmerman et al. 1977:4

Hypolimnetic dissolved-oxygen dynamics within selected White River reservoirs, northern Arkansas-southern Missouri, 1974-2008

USGS Publications Warehouse

De Lanois, Jeanne L.; Green, W. Reed

2011-01-01

Dissolved oxygen is a critical constituent in reservoirs and lakes because it is essential for metabolism by all aerobic aquatic organisms. In general, hypolimnetic temperature and dissolved-oxygen concentrations vary from summer to summer in reservoirs, more so than in natural lakes, largely in response to the magnitude of flow into and release out of the water body. Because eutrophication is often defined as the acceleration of biological productivity resulting from increased nutrient and organic loading, hypolimnetic oxygen consumption rates or deficits often provide a useful tool in analyzing temporal changes in water quality. This report updates a previous report that evaluated hypolimnetic dissolved-oxygen dynamics for a 21-year record (1974-94) in Beaver, Table Rock, Bull Shoals, and Norfork Lakes, as well as analyzed the record for Greers Ferry Lake. Beginning in 1974, vertical profiles of temperature and dissolved-oxygen concentrations generally were collected monthly from March through December at sites near the dam of each reservoir. The rate of change in the amount of dissolved oxygen present below a given depth at the beginning and end of the thermal stratification period is referred to as the areal hypolimnetic oxygen deficit. Areal hypolimnetic oxygen deficit was normalized for each reservoir based on seasonal flushing rate between April 15 and October 31 to adjust for wet year and dry year variability. Annual cycles in thermal stratification within Beaver, Table Rock, Bull Shoals, Norfork, and Greers Ferry Lakes exhibited typical monomictic (one extended turnover period per year) characteristics. Flow dynamics drive reservoir processes and need to be considered when analyzing areal hypolimnetic oxygen deficit rates. A nonparametric, locally weighted scatter plot smooth line describes the relation between areal hypolimnetic oxygen deficit and seasonal flushing rates, without assuming linearity or normality of the residuals. The results in this report are consistent with earlier findings that oxygen deficit rates and flushing-rate adjusted areal hypolimnetic oxygen deficit in Beaver and Table Rock Lakes were decreasing between 1974 and 1994. The additional data (1995-2008) demonstrate that the decline in flushing-rate adjusted areal hypolimnetic oxygen deficit in Beaver Lake has continued, whereas that in Table Rock Lake has flattened out in recent years. The additional data demonstrate the flushing-rate adjusted areal hypolimnetic oxygen deficit in Bull Shoals and Norfork Lakes have declined since 1995 (improved water quality), which was not indicated in earlier studies, while Greers Ferry Lake showed little net change over the period of record. Given the amount of data (35 years) for these reservoirs, developing an equation or model to predict areal hypolimnetic oxygen deficit and, therefore, areal hypolimnetic oxygen content, on any given day during future stratification seasons may be useful for reservoir managers.

Hydrologic reconnaissance of the Wah Wah Valley drainage basin, Millard and Beaver Counties, Utah

USGS Publications Warehouse

Stephens, Jerry C.

1974-01-01

The Wah Wah Valley drainage basin is an area of about 600 square miles (1,550 km2) in Millard and Beaver Counties in southwestern Utah. Surface-water supplies of the area are negligible--total runoff averages about 7,800 acre-feet (9.62 hm3) annually, all streams are ephemeral or intermittent, and surface storage is negligible. Evaporation and transpiration within the basin consume more than 97 percent of total annual precipitation. There is no surface outflow.

Decoupling the Stationary Navier-Stokes-Darcy System with the Beavers-Joseph-Saffman Interface Condition

DOE PAGES

Cao, Yong; Chu, Yuchuan; He, Xiaoming; ...

2013-01-01

This paper proposes a domain decomposition method for the coupled stationary Navier-Stokes and Darcy equations with the Beavers-Joseph-Saffman interface condition in order to improve the efficiency of the finite element method. The physical interface conditions are directly utilized to construct the boundary conditions on the interface and then decouple the Navier-Stokes and Darcy equations. Newton iteration will be used to deal with the nonlinear systems. Numerical results are presented to illustrate the features of the proposed method.

Alternative prey use affects helminth parasite infections in grey wolves.

PubMed

Friesen, Olwyn C; Roth, James D

2016-09-01

Predators affect prey populations not only through direct predation, but also by acting as definitive hosts for their parasites and completing parasite life cycles. Understanding the affects of parasitism on prey population dynamics requires knowing how their predators' parasite community is affected by diet and prey availability. Ungulates, such as moose (Alces americanus) and white-tailed deer (Odocoileus virginianus), are often important prey for wolves (Canis lupus), but wolves also consume a variety of alternative prey, including beaver (Castor canadensis) and snowshoe hare (Lepus americanus). The use of alternative prey, which may host different or fewer parasites than ungulates, could potentially reduce overall abundance of ungulate parasites within the ecosystem, benefiting both wolves and ungulate hosts. We examined parasites in wolf carcasses from eastern Manitoba and estimated wolf diet using stable isotope analysis. Taeniidae cestodes were present in most wolves (75%), reflecting a diet primarily comprised of ungulates, but nematodes were unexpectedly rare. Cestode abundance was negatively related to the wolf's δ(13) C value, indicating diet affects parasite abundance. Wolves that consumed a higher proportion of beaver and caribou (Rangifer tarandus), estimated using Bayesian mixing models, had lower cestode abundance, suggesting the use of these alternative prey can reduce parasite loads. Long-term consumption of beavers may lower the abundance of adult parasites in wolves, eventually lowering parasite density in the region and ultimately benefiting ungulates that serve as intermediate hosts. Thus, alternative prey can affect both predator-prey and host-parasite interactions and potentially affect food web dynamics. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

The impact of small irrigation diversion dams on the recent migration rates of steelhead and redband trout (Oncorhynchus mykiss)

USGS Publications Warehouse

Weigel, Dana E.; Connolly, Patrick J.; Powell, Madison S.

2013-01-01

Barriers to migration are numerous in stream environments and can occur from anthropogenic activities (such as dams and culverts) or natural processes (such as log jams or dams constructed by beaver (Castor canadensis)). Identification of barriers can be difficult when obstructions are temporary or incomplete providing passage periodically. We examine the effect of several small irrigation diversion dams on the recent migration rates of steelhead (Oncorhynchus mykiss) in three tributaries to the Methow River, Washington. The three basins had different recent migration patterns: Beaver Creek did not have any recent migration between sites, Libby Creek had two-way migration between sites and Gold Creek had downstream migration between sites. Sites with migration were significantly different from sites without migration in distance, number of obstructions, obstruction height to depth ratio and maximum stream gradient. When comparing the sites without migration in Beaver Creek to the sites with migration in Libby and Gold creeks, the number of obstructions was the only significant variable. Multinomial logistic regression identified obstruction height to depth ratio and maximum stream gradient as the best fitting model to predict the level of migration among sites. Small irrigation diversion dams were limiting population interactions in Beaver Creek and collectively blocking steelhead migration into the stream. Variables related to stream resistance (gradient, obstruction number and obstruction height to depth ratio) were better predictors of recent migration rates than distance, and can provide important insight into migration and population demographic processes in lotic species.

78 FR 41805 - In the Matter of FirstEnergy Nuclear Operating Company; Beaver Valley Power Station; Independent...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-11

... rescind any of the above conditions, for good cause. IV In accordance with 10 CFR 2.202, FENOC must, and... Register. Where good cause is shown, consideration will be given to extending the time to answer or request... include a statement of good cause for the extension. The answer may consent to this Order. If the answer...

Beaver Brook, Keene, New Hampshire. Flood Damage Reduction Project. Detailed Project Report for Water Resources Development.

DTIC Science & Technology

1984-02-01

Project Report/ Environmental Assessment Beaver Brook, Keene, New Hampshire I ~ j~j~i iii ii.. A Flood Damage Reduction AD-A 14 3 376 I 𔃾, W " FEBRUARY...STATEMENT (of tme abestwee enteed to Sleok I0. Of dlfieme W booer IS. SUPPLEMENTARY MOTES 2 volume set: vol 1- Flood Damage Reduction - vol 2- Flood Damage...that are considered reasonably characteristic of the region, excluding extremely rare combinations. 2 ,4INN (0 ( w a 12 7’ PLATE * -..- ~ -- - 7 ’ k 47

Effects of a beaver pond on runoff processes: comparison of two headwater catchments

USGS Publications Warehouse

Burns, Douglas A.; McDonnell, Jeffery J.

1998-01-01

Natural variations in concentrations of 18O, D, and H4SiO4 in two tributary catchments of Woods Lake in the west-central Adirondack Mountains of New York were measured during 1989–1991 to examine runoff processes and their implications for the neutralization of acidic precipitation by calcium carbonate treatment. The two catchments are similar except that one contained a 1.3 ha beaver pond. Evaporation from the beaver pond caused a seasonal decrease in the slope of the meteoric water line in stream water from the catchment with a beaver pond (WO2). No corresponding change in slope of the meteoric water line was evident in stream water from the other catchment (WO4), nor in ground water nor soil water from either catchment, indicating that evaporative fractionation was not significant. Application of a best-fit sine curve to δ18O data indicated that base flow in both catchments had a residence time of about 100 days. Ground water from a well finished in thick till had the longest residence time (160 days); soil water from the O-horizon and B-horizon had residence times of 63 and 80 days, respectively. Water previously stored within each catchment (pre-event water) was the predominant component of streamflow during spring snowmelt and during spring and autumn rainfall events, but the proportion of streamflow that consisted of pre-event water differed significantly in the two catchments. The proportion of event water (rain and snowmelt) in WO2 was smaller than at WO4 early in the spring snowmelt of March 13–17, 1990, but the proportions of source water components for the two catchments were almost indistinguishable by the peak flow on the third day of the melt. The event water was further separated into surface-water and subsurface-water components by utilizing measured changes in H4SiO4 concentrations in stream water during the snowmelt. Results indicated that subsurface flow was the dominant pathway by which event water reached the stream except during the peak flow of a rain-on-snow event on the last day of the melt. Streamflow from a spring rain storm with dry antecendent conditions two months later (May 16–18, 1990), was less than 5% event water at peak flow in WO2 and 26% in WO4. This change from the runoff pattern in March is attributed to retention of event water in the beaver pond favored by relatively low pre-event storage and isothermal (nonstratified) conditions in the pond that allowed mixing. Streamflow during several autumn storms was about 15–25% event water at peak flow in WO4; the highest values for event water were associated with wet antecedent moisture conditions. These results indicate that a beaver pond can significantly affect the downstream delivery of event water through evaporation and mixing, but provides minimal retention during large runoff events such as snowmelt. Beaver ponds are expected to provide greater opportunity for neutralization of acidic waters during most of the year in catchments treated with calcium carbonate, but little neutralization effect during snowmelt.

Ground-water data: Beaver, Escalante, Cedar City, and Parowan Valleys; parts of Washington, Iron, Beaver, and Millard Counties, Utah

USGS Publications Warehouse

Sandberg, George W.

1963-01-01

This report is intended to serve two purposes: (1) to make available to the public basic ground-water data useful in planning and studying development of water resources, and (2) to supplement an interpretive report that will be published later.Records were collected during the period 1935-62 by the U.S. Geological Survey in cooperation with the Utah State Engineer as part of the investigation of ground-water conditions in the Beaver, Escalante, Cedar City, and Parowan Walleys. This report will include records collected subsequent to data published in earlier reports listed in the bibliography. The interpretive material will be published in a companion report by George W. Sandberg.This report is most useful in predicting conditions likely to be found in areas that are being considered as well sites. The person considering the new well can spot the proposed site on plate 1 and examine the records of nearby wells as shown in the tables and figure 2. From table 1 he can note such things as diameter, depth, water level, yield, use of water, and depth to aquifers in wells in the vicinity, and from the well logs in table 3 he can note the type of material that yields water to the wells. Table 2 gives several years record of yields and pumping levels of irrigation wells, and in table 4 are the chemical analyses of water from wells and springs. Figure 2 shows the historic fluctuations and trends of water levels in the four valleys. If the reader decides from his examination that conditions are favorable, he can place an application to drill a well with the State Engineer. During the past several years, however, the State Engineer has rejected new applications to appropriate water in major portions of Beaver Valley, Milford and Beryl-Enterprise districts in Escalante Valley, and Cedar City Valley. Anyone seeking to initiate a new ground-water right in any of these areas should obtain information from the State Engineer's Office in either Salt Lake City or Cedar City to determine the likelihood of approval of the required application.The report is also useful when planning large-scale developments of water supply. This and other uses of the report will be helped by use of the interpretive report upon its release.

Synthesis of monthly and annual streamflow records (water years 1950-2003) for Big Sandy, Clear, Peoples, and Beaver Creeks in the Milk River basin, Montana

USGS Publications Warehouse

Parrett, Charles

2006-01-01

To address concerns expressed by the State of Montana about the apportionment of water in the St. Mary and Milk River basins between Canada and the United States, the International Joint Commission requested information from the United States government about water that originates in the United States but does not cross the border into Canada. In response to this request, the U.S. Geological Survey synthesized monthly and annual streamflow records for Big Sandy, Clear, Peoples, and Beaver Creeks, all of which are in the Milk River basin in Montana, for water years 1950-2003. This report presents the synthesized values of monthly and annual streamflow for Big Sandy, Clear, Peoples, and Beaver Creeks in Montana. Synthesized values were derived from recorded and estimated streamflows. Statistics, including long-term medians and averages and flows for various exceedance probabilities, were computed from the synthesized data. Beaver Creek had the largest median annual discharge (19,490 acre-feet), and Clear Creek had the smallest median annual discharge (6,680 acre-feet). Big Sandy Creek, the stream with the largest drainage area, had the second smallest median annual discharge (9,640 acre-feet), whereas Peoples Creek, the stream with the second smallest drainage area, had the second largest median annual discharge (11,700 acre-feet). The combined median annual discharge for the four streams was 45,400 acre-feet. The largest combined median monthly discharge for the four creeks was 6,930 acre-feet in March, and the smallest combined median monthly discharge was 48 acre-feet in January. The combined median monthly values were substantially smaller than the average monthly values. Overall, synthesized flow records for the four creeks are considered to be reasonable given the prevailing climatic conditions in the region during the 1950-2003 base period. Individual estimates of monthly streamflow may have large errors, however. Linear regression was used to relate logarithms of combined annual streamflow to water years 1950-2003. The results of the regression analysis indicated a significant downward trend (regression line slope was -0.00977) for combined annual streamflow. A regression analysis using data from 1956-2003 indicated a slight, but not significant, downward trend for combined annual streamflow.

Revisiting 26Al-26Mg systematics of plagioclase in H4 chondrites

NASA Astrophysics Data System (ADS)

Telus, M.; Huss, G. R.; Nagashima, K.; Ogliore, R. C.

2014-06-01

Zinner and Göpel found clear evidence for the former presence of 26Al in the H4 chondrites Ste. Marguerite and Forest Vale. They assumed that the 26Al-26Mg systematics of these chondrites date "metamorphic cooling of the H4 parent body." Plagioclase in these chondrites can have very high Al/Mg ratios and low Mg concentrations, making these ion probe analyses susceptible to ratio bias, which is inversely proportional to the number of counts of the denominator isotope (Ogliore et al.). Zinner and Göpel used the mean of the ratios to calculate the isotope ratios, which exacerbates this problem. We analyzed the Al/Mg ratios and Mg isotopic compositions of plagioclase grains in thin sections of Ste. Marguerite, Forest Vale, Beaver Creek, and Sena to evaluate the possible influence of ratio bias on the published initial 26Al/27Al ratios for these meteorites. We calculated the isotope ratios using total counts, a less biased method of calculating isotope ratios. The results from our analyses are consistent with those from Zinner and Göpel, indicating that ratio bias does not significantly affect 26Al-26Mg results for plagioclase in these chondrites. Ste. Marguerite has a clear isochron with an initial 26Al/27Al ratio indicating that it cooled to below 450 °C 5.2 ± 0.2 Myr after CAIs. The isochrons for Forest Vale and Beaver Creek also show clear evidence that 26Al was alive when they cooled, but the initial 26Al/27Al ratios are not well constrained. Sena does not show evidence that 26Al was alive when it cooled to below the Al-Mg closure temperature. Given that metallographic cooling rates for Ste. Marguerite, Forest Vale, and Beaver Creek are atypical (>5000 °C/Myr at 500 °C) compared with most H4s, including Sena, which have cooling rates of 10-50 °C/Myr at 500 °C (Scott et al.), we conclude that the Al-Mg systematics for Ste. Marguerite, Forest Vale, and Beaver Creek are the result of impact excavation of these chondrites and cooling at the surface of the parent body, instead of undisturbed cooling at depth in the H chondrite parent body, like many have assumed.

Ice processes affect habitat use and movements of adult cutthroat trout and brook trout in a Wyoming foothills stream

USGS Publications Warehouse

Lindstrom, J.W.; Hubert, W.A.

2004-01-01

Habitat use and movements of 25 adult cutthroat trout Oncorhynchus clarkii and 25 adult brook trout Salvelinus fontinalis from fall through winter 2002-2003 were assessed by means of radiotelemetry in a 7-km reach of a Rocky Mountains foothills stream. Temporal dynamics of winter habitat conditions were evaluated by regularly measuring the features of 30 pools and 5 beaver Castor canadensis ponds in the study reach. Groundwater inputs at three locations raised mean daily water temperatures in the stream channel during winter to 0.2-0.6??C and kept at least 250 m of the downstream channel free of ice, but the lack of surface ice further downstream led to the occurrence of frazil ice and anchor ice in pools and unstable habitat conditions for trout. Pools in segments that were not affected by groundwater inputs and beaver ponds tended to be stable and snow accumulated on the surface ice. Pools throughout the study reach tended to become more stable as snow accumulated. Both cutthroat trout and brook trout selected beaver ponds as winter progressed but tended to use lateral scour pools in proportion to their availability. Tagged fish not in beaver ponds selected lateral scour pools that were deeper than average and stable during winter. Movement frequencies by tagged fish decreased from fall through winter, but some individuals of both species moved during winter. Ice processes affected both the habitat use and movement patterns of cutthroat trout and brook trout in this foothills stream.

Measuring taste impairment in epidemiologic studies: the Beaver Dam Offspring Study.

PubMed

Cruickshanks, K J; Schubert, C R; Snyder, D J; Bartoshuk, L M; Huang, G H; Klein, B E K; Klein, R; Nieto, F J; Pankow, J S; Tweed, T S; Krantz, E M; Moy, G S

2009-07-01

Taste or gustatory function may play an important role in determining diet and nutritional status and therefore indirectly impact health. Yet there have been few attempts to study the spectrum of taste function and dysfunction in human populations. Epidemiologic studies are needed to understand the impact of taste function and dysfunction on public health, to identify modifiable risk factors, and to develop and test strategies to prevent clinically significant dysfunction. However, measuring taste function in epidemiologic studies is challenging and requires repeatable, efficient methods that can measure change over time. Insights gained from translating laboratory-based methods to a population-based study, the Beaver Dam Offspring Study (BOSS) will be shared. In this study, a generalized labeled magnitude scale (gLMS) method was used to measure taste intensity of filter paper disks saturated with salt, sucrose, citric acid, quinine, or 6-n-propylthiouracil, and a gLMS measure of taste preferences was administered. In addition, a portable, inexpensive camera system to capture digital images of fungiform papillae and a masked grading system to measure the density of fungiform papillae were developed. Adult children of participants in the population-based Epidemiology of Hearing Loss Study in Beaver Dam, Wisconsin, are eligible for this ongoing study. The parents were residents of Beaver Dam and 43-84 years of age in 1987-1988; offspring ranged in age from 21-84 years in 2005-2008. Methods will be described in detail and preliminary results about the distributions of taste function in the BOSS cohort will be presented.

Surgical sterilization: an underutilized procedure for evaluating the merits of induced sterility

USGS Publications Warehouse

Kennelly, James J.; Converse, Kathryn A.

1993-01-01

Despite more than 4 decades of effort, development of effective wildlife damage control programs based on sterilization of target species has met with limited success. This is partly due to the fact that investigators have assumed, rather than empirically tested, whether the reproductive strategies of the target populations were vulnerable to the planned treatment. Equally important, methods selected to include sterility usually involve a chemical agent that can affect sociosexual behaviors of the nuisance population. In this report, we illustrate how surgically induced sterility circumvents both problems--how the concept without the potentially confounding secondary effects of a chemical. We assessed the merits of initiating research to develop a male chemosterilant for Norway rats, red-winged blackbirds, beaver, and Canada geese by inducing sterility surgically. The infidelity of many red-winged females to their polygynous territorial male was surprising and argued against searching for a male sterilant. On the other hand, beaver and Canada goose studies confirmed previous reports that both form par-bonds and are monogamous. Both should be vulnerable to a male chemosterilant approach, and research toward this goal is justified.

Interannual and long-term changes in the trophic state of a multibasin lake: Effects of morphology, climate, winter aeration, and beaver activity

USGS Publications Warehouse

Robertson, Dale M.; Rose, William; Reneau, Paul C.

2016-01-01

Little St. Germain Lake (LSG), a relatively pristine multibasin lake in Wisconsin, USA, was examined to determine how morphologic (internal), climatic (external), anthropogenic (winter aeration), and natural (beaver activity) factors affect the trophic state (phosphorus, P; chlorophyll, CHL; and Secchi depth, SD) of each of its basins. Basins intercepting the main flow and external P sources had highest P and CHL and shallowest SD. Internal loading in shallow, polymictic basins caused P and CHL to increase and SD to decrease as summer progressed. Winter aeration used to eliminate winterkill increased summer internal P loading and decreased water quality, while reductions in upstream beaver impoundments had little effect on water quality. Variations in air temperature and precipitation affected each basin differently. Warmer air temperatures increased productivity throughout the lake and decreased clarity in less eutrophic basins. Increased precipitation increased P in the basins intercepting the main flow but had little effect on the isolated deep West Bay. These relations are used to project effects of future climatic changes on LSG and other temperate lakes.

Genus Francisella.

DTIC Science & Technology

1981-05-15

temperatures for 30 min-. Cool to 45 - 48°C. Aseptically add 25 ml of packed, human blood cells or 50 ml of defibrinated rabbit or sheep blood. Mix...now included in var. palaearctica, is reported to ferment glycerol but not maltose (Kunitsa et al., 1972). Growth in litmus milk is scant; slight...muskrats, water rats, beavers, squirrels;, woodclhocks, sheep , mice, voles and game birds as well as biting insects (usuallv ticks or deer flies

The coal deposits of the Alkali Butte, the Big Sand Draw, and the Beaver Creek fields, Fremont County, Wyoming

USGS Publications Warehouse

Thompson, Raymond M.; White, Vincent L.

1952-01-01

Large coal reserves are present in three areas located between 12 and 20 miles southeast of Riverton, Fremont County, central Wyoming. Coal in two of these areas, the Alkali Butte coal field and the Big Sand Draw coal field, is exposed on the surface and has been developed to some extent by underground mining. The Beaver Creek coal field is known only from drill cuttings and cores from wells drilled for oil and gas in the Beaver Creek oil and gas field.These three coal areas can be reached most readily from Riverton, Wyo. State Route 320 crosses Wind River about 1 mile south of Riverton. A few hundred yards south of the river a graveled road branches off the highway and extends south across the Popo Agie River toward Sand Draw oil and gas field. About 8 miles south of the highway along the Sand Draw road, a dirt road bears east and along this road it is about 12 miles to the Bell coal mine in the Alkali Butte coal field. Three miles southeast of the Alkali Butte turn-off, 3 miles of oiled road extends southwest into the Beaver Creek oil and gas field. About 6 miles southeast of the Beaver Creek turn-off, in the valley of Little Sand Draw Creek, a dirt road extends east 1. mile and then southeast 1 mile to the Downey mine in the Big Sand Draw coal field. Location of these coal fields is shown on figure 1 with their relationship to the Wind River basin and other coal fields, place localities, and wells mentioned in this report. The coal in the Alkali Butte coal field is exposed partly on the Wind River Indian Reservation in Tps. 1 and 2 S., R. 6 E., and partly on public land. Coal in the Beaver Creek and Big Sand Draw coal fields is mainly on public land. The region has a semiarid climate with rainfall averaging less than 10 in. per year. When rain does fall the sandy-bottomed stream channels fill rapidly and are frequently impassable for a few hours. Beaver Creek, Big Sand Draw, Little Sand Draw, and Kirby Draw and their smaller tributaries drain the area and flow northwestward to the Wind River. This report is based almost entirely upon geologic investigations made in 1949 as a part of the program of the Department of the Interior for development of the Missouri River basin. Some coal sections were measured in 1950 and the additional information on the Big Sand Draw coal field was obtained in 1951. A geologic map of the Beaver Creek field was not prepared for this report because most of the significant coal occurs below a depth of 1,400 ft and is not exposed on the surface. Mr. George Downey, Lander, Wyo. , supplied much helpful information on the Big Sand Draw coal field and the area in general. Topographic contours shown on figures 11, 12, 13, and 14 are from unpublished plane-table sheets made by E. D. Woodruff in 1912. Previous geologic investigations of the region have been made by E. G. Woodruff and D. E. Winchester (1912), by C. J. Hares (1916), by A. J. Collier (1920), and C. M. Bauer (1934). Except for the work of Woodruff and Winchester, which was an areal examination for the purpose of classifying the public lands, the geological investigatiohs were of a general nature and give little detail of the coal beds. Berryhill (1950) summarizes Woodruff and Winchester's work.

An 11 000-year-long record of fire and vegetation history at Beaver Lake, Oregon, central Willamette Valley

USGS Publications Warehouse

Walsh, Megan K.; Pearl, Christopher A.; Whitlock, Cathy; Bartlein, Patrick J.; Worona, Marc A.

2010-01-01

High-resolution macroscopic charcoal and pollen analysis were used to reconstruct an 11??000-year-long record of fire and vegetation history from Beaver Lake, Oregon, the first complete Holocene paleoecological record from the floor of the Willamette Valley. In the early Holocene (ca 11??000-7500 calendar years before present [cal??yr??BP]), warmer, drier summers than at present led to the establishment of xeric woodland of Quercus, Corylus, and Pseudotsuga near the site. Disturbances (i.e., floods, fires) were common at this time and as a result Alnus rubra grew nearby. High fire frequency occurred in the early Holocene from ca 11??200-9300??cal??yr??BP. Riparian forest and wet prairie developed in the middle Holocene (ca 7500??cal??yr??BP), likely the result of a decrease in the frequency of flooding and a shift to effectively cooler, wetter conditions than before. The vegetation at Beaver Lake remained generally unchanged into the late Holocene (from 4000??cal??yr??BP to present), with the exception of land clearance associated with Euro-American settlement of the valley (ca 160??cal??yr BP). Middle-to-late Holocene increases in fire frequency, coupled with abrupt shifts in fire-episode magnitude and charcoal composition, likely indicate the influence anthropogenic burning near the site. The paleoecological record from Beaver Lake, and in particular the general increase in fire frequency over the last 8500??years, differs significantly from other low-elevation sites in the Pacific Northwest, which suggests that local controls (e.g., shifts in vegetation structure, intensification of human land-use), rather than regional climatic controls, more strongly influenced its environmental history. ?? 2010 Elsevier Ltd.

Nuclear and mitochondrial genetic structure in the Eurasian beaver (Castor fiber) – implications for future reintroductions

PubMed Central

Senn, Helen; Ogden, Rob; Frosch, Christiane; Syrůčková, Alena; Campbell-Palmer, Roisin; Munclinger, Pavel; Durka, Walter; Kraus, Robert H S; Saveljev, Alexander P; Nowak, Carsten; Stubbe, Annegret; Stubbe, Michael; Michaux, Johan; Lavrov, Vladimir; Samiya, Ravchig; Ulevicius, Alius; Rosell, Frank

2014-01-01

Many reintroduction projects for conservation fail, and there are a large number of factors that may contribute to failure. Genetic analysis can be used to help stack the odds of a reintroduction in favour of success, by conducting assessment of source populations to evaluate the possibility of inbreeding and outbreeding depression and by conducting postrelease monitoring. In this study, we use a panel of 306 SNP (single nucleotide polymorphism) markers and 487–489 base pairs of mitochondrial DNA control region sequence data to examine 321 individuals from possible source populations of the Eurasian beaver for a reintroduction to Scotland. We use this information to reassess the phylogenetic history of the Eurasian beavers, to examine the genetic legacy of past reintroductions on the Eurasian landmass and to assess the future power of the genetic markers to conduct ongoing monitoring via parentage analysis and individual identification. We demonstrate the capacity of medium density genetic data (hundreds of SNPs) to provide information suitable for applied conservation and discuss the difficulty of balancing the need for high genetic diversity against phylogenetic best fit when choosing source population(s) for reintroduction. PMID:25067948

Dam Dynamics in the Colonial Northeast and Chesapeake: Hydrologic Implications

NASA Astrophysics Data System (ADS)

Bain, D. J.; Salant, N. L.; Brandt, S. L.

2008-12-01

Recent work has highlighted the widespread presence of low-head dams for power generation during the 19th century. However, this work largely depends on census numbers tabulated in the mid-1800s, over 200 years after European activity began in North America. In order to compare the hydrologic implications of colonial era low-head dam construction with the impacts of other simultaneous processes (e.g., expatriation of the beaver or forest clearance), we have compiled historical data on mills to reconstruct the temporal and spatial dynamics of low-head dam construction in the colonial northeastern United States (i.e., Virginia to Maine). This reconstruction, combined with the results of related work on beaver pond dynamics and deforestation, provides several insights into the distribution and impacts of human impoundments during this period. While the resulting hydrologic changes are large, the addition of human dams to the system seems to be minimally offset and less important than changes arising from the expatriation of the beaver or the removal of trees during this early period. In addition, the spatial patterns of dam construction are complex, making prediction of hydrologic and associated responses more difficult to predict.

Distributed Temperature Sensing of hyporheic flux patterns in varied space and time around beaver dams

NASA Astrophysics Data System (ADS)

Briggs, M.; Lautz, L. K.; McKenzie, J. M.

2010-12-01

Small dams enhance hyporheic interaction by creating punctuated head differentials along streams, thereby affecting redox conditions and nutrient cycling in the streambed. As beaver populations return, they create dams that alter hyporheic flowpaths locally, an effect which may integrate at the reach scale to produce a net hydrological and ecological functional change. Streambed heterogeneity around beaver dams combines with varied morphology, head differentials and stream velocities to create patterns of hyporheic seepage flux that vary in both space and time. Heat has been used as a groundwater tracer for many years, but it’s dependence on spatially disperse point measurements has only recently been resolved by the development of Distributed Temperature Sensing (DTS) fiber-optic technology. Modified applications of DTS include wrapping the fiber around a mandrel to increase spatial resolution dramatically. Wrapped configurations can be installed vertically in the streambed to provide data for heat transport modeling of vertical hyporheic flux. The vertically continuous dataset generated with DTS may be more informative regarding subsurface heterogeneity than more commonly used spatially discrete thermocouples. We installed a total of nine wrapped DTS rods with 1.4 cm vertical spatial resolution above two beaver dams in Cherry Creek, a tributary of the Little Popo Agie River in Lander, Wyoming, USA. Data was collected over 20 min periods in dual-ended mode continuously for one month (10-Jul to 10-Aug 2010) during baseflow recession, as discharge dropped from 384 Ls-1 to 211 Ls-1. The temperature rods were installed to at least 0.75 m depth within bed sediments at varied distances upstream of the dams in diverse stream morphological units, which ranged from gravel bars to clay lined pools. Diurnal fluctuations in stream temperature were generally between 4.5 and 5.5 oC in amplitude, imparting a strong potential signal for propagation into the bed due to advective hyporheic flux. In many locations monthly temperature standard deviations at the 10 cm depth were larger than that of the overlying stream water, indicating direct heating of the streambed by solar radiation was an important process, even in that high velocity system. The high-resolution temperature records revealed local heterogeneity in the streambed at each rod and indicated the largest hyporheic flux was within gravel bars close to the dams. The smallest flux was through a gravel bar farther upstream of the dam, and through the deepest portions of pools closer to the dam. High flux regions had monthly temperature standard deviations close to that of the stream (1.5 oC) at shallow depths, while shallow sediments in pools had much more muted temperature oscillations. At 0.5 m depth, all rods had similar, smaller temperature standard deviations, ranging from 0.64-0.80 oC. The extensive and spatially continuous data set generated using DTS allowed us to determine hyporheic flux patterns for virtually any depth and time along the high-resolution temperature rods, a crucial step for understanding transient patterns in biogeochemical processing around beaver dams.

A Report of Archaeological Testing at Site 3CT263 Within the Proposed Edmondson Wastewater Pond, Crittendon County, Arkansas

DTIC Science & Technology

1990-09-01

Reservoirs. For U. S. Army Corps of Engineers. 1974b Archaeological Reconnaissance of the Reelfoot - Lake No. 9 Project Impact Area, Fulton Co., Kentucky...bayous, and lakes . Major drainages in Crittenden County include the Tvronza River, Fifteenmile Bayou, Tenmile Bayou, and Big Creek. The proposed...and canadian geese (Branta canadensis). Fish from the larger streams, oxbow lakes and beaver ponds, were also an important food source for

Analysis and Interpretation of Artifact Collections from Site 3CT271, Randolph Estate Development, Crittenden County, Arkansas

DTIC Science & Technology

1991-02-01

The county has many streams, bayous, and lakes . Major drainages in Crittenden County include the Tyronza River, Fifteenmile Bayou, Tenmile Bayou, and...and canadian geese (Bra nta canadensis). -Fish from the larger streams, oxbow lakes , and beaver ponds, U such as the flathead catfish, alligator gar...type site for the Big Lake phase., Similar components have been recently recognized along the Mississippi River drainage just east of the project area

Transport of Cryptosporidium, Giardia, Source-specific Indicator Organisms, and Standard Water Quality Constituents During Storm Events

NASA Astrophysics Data System (ADS)

Sturdevant-Rees, P. L.; Bourdeau, D.; Baker, R.; Long, S. C.; Barten, P. K.

2004-05-01

Microbial and water-quality measurements are collected during storm events under a variety of meteorological and land-use conditions in order to 1) identify risk of Cryptosporidium oocysts, Giardia cysts and other constituents, including microbial indicator organisms, entering surface waters from various land uses during periods of surface runoff; 2) optimize storm sampling procedures for these parameters; and 3) optimize strategies for accurate determination of constituent loads. The investigation is focused on four isolated land uses: forested with free ranging wildlife, beaver influenced forested with free ranging wildlife, residential/commercial, and dairy farm grazing/pastureland using an upstream and downstream sampling strategy. Traditional water-quality analyses include pH, temperature, turbidity, conductivity, total suspended solids, total phosphorus, total Kjeldahl-nitrogen, and ammonia nitrogen, Giardia cysts and Cryptosporidium oocysts. Total coliforms and fecal coliforms are measured as industry standard microbial analyses. Sorbitol-fermenting Bifidobacteria, Rhodococcus coprophilus, Clostridium perfringens spores, and Somatic and F-specific coliphages are measured at select sites as potential alternative source-specific indicator organisms. Upon completion of the project, the final database will consist of wet weather transport data for a set of parameters during twenty-four distinct storm-events in addition to monthly baseline data. A subset of the results to date will be presented, with focus placed on demonstrating the impact of beaver on constituent loadings over a variety of hydrologic and meteorological conditions.

Pesticide movement in soils; a comparison of no-tillage and conventional tillage in the Beaver Creek watershed in West Tennessee

USGS Publications Warehouse

Olsen, Lisa D.

1995-01-01

In 1993, a study of pesticide movement and degradation in soils was intitated in the Beaver Creek watershed, which consists of about 95,000 acres and includes some of the Nation's most highly erodible soils. Resource-management agencies in this locality have recommended conservation tillage or "no-tillage" as a best management practices to control soil erosion. The pesticide aldicarb was selected for this study because it is both highly mobile and extremely toxic. Horizontal movement of aldicarb and its metabolites was negligible. Vertical movement of aldicarb and its metabolites was limited to the top 2.5 feet of soil. Most of the aldicarb residue (over 85 percent) remaining in the soil after 148 days was detected in the top 0.5 foot of soil. No significant differences in the movement or degradation of aldicarb and its metabolites were observed between the no-tilled and conventionally tilled fields. No-till practices did not increase the downward movement of aldicarb in the test areas. No-tillage has proven to be an effective best management practice for soil-loss reduction in many studies throughout the United States.

Using the PDSI to Estimate Summer Stream Discharge in the Greater Yellowstone Ecosystem: Implications for 20th Century Riparian Habitat Variability

NASA Astrophysics Data System (ADS)

Persico, L.; Meyer, G. A.

2013-12-01

Small streams at lower elevations in the Greater Yellowstone Ecosystem (GYE) create riparian habitat in an otherwise dry environment. Riparian area can be expanded by beaver damming, which increases channel wetted area and local water tables, and allows fine-grained organic-rich sediment to accumulate. However, increases can be countered by severe drought. The loss of riparian area is potentially greatest in small basins dependent on snowpack for base flow, where prolonged severe drought may reduce base flow to zero. Discharge records are often lacking for basins < 20 km^2, making it difficult to directly examine how climate has impacted flow. The Palmer Drought Severity Index (PDSI) is a useful proxy for large-scale variations in available moisture. PDSI values for climate divisions are estimated from spatially weighted weather station measurements of temperature and precipitation. We use divisional PDSI values to estimate discharge on GYE small streams since 1900. USGS stream-gauge sites were regressed with the corresponding PDSI for each climate division. We also use a regional (2.5° by 2.5°) reconstruction of the PDSI based on 30 tree ring chronologies (Cook et al., 2004) to estimate discharge during the most severe two and ten year droughts (AD 1150-1151 and 805-796, respectively) during the Medieval Climatic Anomaly (MCA). The MCA is a period of high climate variability and widespread drought in the GYE. Significant correlations between stream discharge and the PDSI occur during the late summer and early fall and the strongest correlation between discharge and the PDSI occurs for the 3-month PDSI average centered on August. Stream-gauge records with bootstrapped correlation values greater than 0.65 were chosen for regression analyses. To estimate stream flows for ungauged stream reaches, stepwise multiple regression analyses were performed using measured stream flows and independent basin characteristics. Basin area and mean elevation are significant predictors of discharge (α < 0.05). The 1930s Dust Bowl drought was one of the most severe droughts in the past 300 years; from 1934-1935, average August discharge was reduced by 25-40% with respect to the anomalously wet early 20th century pluvial. Discharge estimates using reconstructed PDSI values for the 2- and 10-year MCA droughts (PDSI = -6 and -5, respectively) indicate that 60% of stream reaches where beaver were active in the late Holocene became ephemeral in these droughts. This analysis is supported by observations during the extreme drought of the 2000s, when ephemeral flow occurred along streams with known historical beaver activity in northern Yellowstone. Model predictions indicate that by 2030-2039 the GYE will endure persistent severe drought (mean annual PDSI = -4 to -6) (Dai, 2011), thus riparian area is likely to decrease in the coming decades. The early 20th century has been suggested to be an ideal reference for riparian habitat restoration despite anomalously wet conditions unlike current or likely future climate. Future efforts to restore riparian habitat by reducing elk browsing and increasing beaver damming will be hampered by reduced flows on small streams.

Post-fire debris-flow hazard assessment of the area burned by the 2013 Beaver Creek Fire near Hailey, central Idaho

USGS Publications Warehouse

Skinner, Kenneth D.

2013-01-01

A preliminary hazard assessment was developed for debris-flow hazards in the 465 square-kilometer (115,000 acres) area burned by the 2013 Beaver Creek fire near Hailey in central Idaho. The burn area covers all or part of six watersheds and selected basins draining to the Big Wood River and is at risk of substantial post-fire erosion, such as that caused by debris flows. Empirical models derived from statistical evaluation of data collected from recently burned basins throughout the Intermountain Region in Western United States were used to estimate the probability of debris-flow occurrence, potential volume of debris flows, and the combined debris-flow hazard ranking along the drainage network within the burn area and to estimate the same for analyzed drainage basins within the burn area. Input data for the empirical models included topographic parameters, soil characteristics, burn severity, and rainfall totals and intensities for a (1) 2-year-recurrence, 1-hour-duration rainfall, referred to as a 2-year storm (13 mm); (2) 10-year-recurrence, 1-hour-duration rainfall, referred to as a 10-year storm (19 mm); and (3) 25-year-recurrence, 1-hour-duration rainfall, referred to as a 25-year storm (22 mm). Estimated debris-flow probabilities for drainage basins upstream of 130 selected basin outlets ranged from less than 1 to 78 percent with the probabilities increasing with each increase in storm magnitude. Probabilities were high in three of the six watersheds. For the 25-year storm, probabilities were greater than 60 percent for 11 basin outlets and ranged from 50 to 60 percent for an additional 12 basin outlets. Probability estimates for stream segments within the drainage network can vary within a basin. For the 25-year storm, probabilities for stream segments within 33 basins were higher than the basin outlet, emphasizing the importance of evaluating the drainage network as well as basin outlets. Estimated debris-flow volumes for the three modeled storms range from a minimal debris flow volume of 10 cubic meters [m3]) to greater than 100,000 m3. Estimated debris-flow volumes increased with basin size and distance downstream. For the 25-year storm, estimated debris-flow volumes were greater than 100,000 m3 for 4 basins and between 50,000 and 100,000 m3 for 10 basins. The debris-flow hazard rankings did not result in the highest hazard ranking of 5, indicating that none of the basins had a high probability of debris-flow occurrence and a high debris-flow volume estimate. The hazard ranking was 4 for one basin using the 10-year-recurrence storm model and for three basins using the 25-year-recurrence storm model. The maps presented herein may be used to prioritize areas where post-wildfire remediation efforts should take place within the 2- to 3-year period of increased erosional vulnerability.

Analysis and Interpretation of Artifact Collections from four Archaeological Sites within the Country Club Gardens Permit Area, West Memphis, Crittenden County, Arkansas

DTIC Science & Technology

1990-12-01

Excavation at Chucallssa (40SY1). Laboratory work at C.H. Nash Museum. Testing of suspected mound site near Reelfoot Lake , Obion County, Tennessee...Ferguson 1974:2). The county has many streams, bayov s, and lakes . Major drainages in Crittenden County include the Tyronza River, Fifteenmile Bayou...Branta canadensis). Fish from the larger streams, oxbow lakes and beaver ponds, such as the flathead catfish, alligator gar, drum, buffalo, largemouth

High and novel genetic diversity of Francisella tularensis in Germany and indication of environmental persistence.

PubMed

Schulze, C; Heuner, K; Myrtennäs, K; Karlsson, E; Jacob, D; Kutzer, P; GROßE, K; Forsman, M; Grunow, R

2016-10-01

In Germany tularemia is a re-emerging zoonotic disease. Therefore, we investigated wild animals and environmental water samples for the presence and phylogenetic diversity of Francisella tularensis in the poorly studied Berlin/Brandenburg region. The phylogenomic analysis of three isolates from wild animals revealed three new subclades within the phylogenetic tree of F. tularensis [B.71 from a raccoon dog (Nyctereutes procyonoides); B.74 from a red fox (Vulpes vulpes), and B.75 from a Eurasian beaver (Castor fiber albicus)]. The results from histological, PCR, and genomic investigations on the dead beaver showed that the animal suffered from a systemic infection. Indications were found that the bacteria were released from the beaver carcass into the surrounding environment. We demonstrated unexpectedly high and novel phylogenetic diversity of F. tularensis in Germany and the fact that the bacteria persist in the environment for at least one climatic season. These findings support a broader host species diversity than previously known regarding Germany. Our data further support the assumption derived from previous serological studies of an underestimated frequency of occurrence of the pathogen in the environment and in wild animals. F. tularensis was isolated from animal species not previously reported as natural hosts in Germany.

Compliance of the Savannah River Site D-Area cooling system with environmental regulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Specht, W.L.; Mackey, H.E.; Paller, M.H.

1990-08-01

This document presents information relating to a demonstration under Section 316(a) of the Clean Water Act for the 400-D Area cooling system at the Savannah River Site (SRS) near Aiken, South Carolina. The demonstration was mandated because the National Pollution Discharge Elimination System (NPDES) permit for SRS (SC0000175), granted on January 1, 1984, specified in-stream temperature limits in SRS streams of 32.2{degree}C and a {Delta}T limit of 2.8{degree}C above ambient. To achieve compliance with in-stream temperature limits, the Department of Energy (DOE) and the South Carolina Department of Health and Environmental Control (SCDHEC) entered into a Consent Order (84-4-W) whichmore » temporarily superseded the temperature requirements and identified a process for attaining compliance. The preferred option for achieving thermal compliance in Beaver Dam Creek consisted of increased flow, with mixing of the raw water basin overflow with the cooling water discharge during the summer months. Although this action can achieve instream temperatures of less than 32.2{degree}C, {Delta}T's still exceed 2.8{degree}C. Therefore, a 316 (a) Demonstration was initiated to determine whether a balanced indigenous biological community can be supported in the receiving stream with {Delta}T's in excess of 2.8{degree}C. A Biological Monitoring Program for Beaver Dam Creek was approved by SCDHEC in June 1988 and implemented in September 1988. The program monitored the water quality, habitat formers, zooplankton, macroinvertebrates, fish, other vertebrate wildlife and threatened and endangered species in Beaver Dam Creek for an 18-month period (September 1988-February 1990). This document summarizes information collected during the monitoring program and evaluates the data to determine whether Beaver Dam Creek presently supports a balanced indigenous biological community. 97 refs., 32 figs., 51 tabs.« less

Ductile shear in granitic gneisses adjacent to the Beaver Creek fault zone, northwest lowlands, New York State

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marcoline, J.

1993-03-01

Greenville-age rocks are exposed in the Beaver Creek area in the Northwest Lowlands of New York State. The prominent structural grain in the area strikes approximately N40E and is defined by a series of metasedimentary and metaigneous rocks elongate parallel to the Beaver Creek Fault Zone. A series of 7 granitic augen gneiss bodies lies to the west of the fault. These bodies are elongate parallel to the Beaver Creek Fault Zone and are bordered by metasedimentary units. Structural analysis of the 7 granitic gneiss bodies shows that the bodies underwent several phases of ductile shear. These shearing events aremore » responsible for both fabric development and the overall shape of the bodies. The granitic gneiss is a well-foliated and lineated augen gneiss. The foliation is defined by biotite alignment, quartz ribbons, and feldspar augen. The foliation has a strike of N42E, with dips ranging from 85SE to vertical. Quartz ribbon lineations plunge 20--25 NE. The gneiss exhibits three distinct ductile shear fabrics showing oblique slip with a large strike-slip component. Fabric asymmetry indicates oblique slip with a large component of sinistral shear. The second shear fabric is somewhat recovered but not annealed. Quartz ribbons are dominantly monogranular and many show pronounced undulose extinction. Feldspar porphyroclasts form well-defined sigma grains showing a component of sinistral shear. The youngest ductile shear fabric is defined by quartz grain shape preferred orientation and mica fish. This third fabric exhibits a component of dextral shear, rather than sinistral shear. A late cataclastic texture crosscuts the earlier ductile fabrics. The elongate character of the 7 bodies and their NE/SE alignment is probably due to the regional shearing processes responsible for forming the fabric in the rocks.« less

A SIMULINK environment for flight dynamics and control analysis: Application to the DHC-2 Beaver. Part 1: Implementation of a model library in SIMULINK. Part 2: Nonlinear analysis of the Beaver autopilot

NASA Technical Reports Server (NTRS)

Rauw, Marc O.

1993-01-01

The design of advanced Automatic Aircraft Control Systems (AACS's) can be improved upon considerably if the designer can access all models and tools required for control system design and analysis through a graphical user interface, from within one software environment. This MSc-thesis presents the first step in the development of such an environment, which is currently being done at the Section for Stability and Control of Delft University of Technology, Faculty of Aerospace Engineering. The environment is implemented within the commercially available software package MATLAB/SIMULINK. The report consists of two parts. Part 1 gives a detailed description of the AACS design environment. The heart of this environment is formed by the SIMULINK implementation of a nonlinear aircraft model in block-diagram format. The model has been worked out for the old laboratory aircraft of the Faculty, the DeHavilland DHC-2 'Beaver', but due to its modular structure, it can easily be adapted for other aircraft. Part 1 also describes MATLAB programs which can be applied for finding steady-state trimmed-flight conditions and for linearization of the aircraft model, and it shows how the built-in simulation routines of SIMULINK have been used for open-loop analysis of the aircraft dynamics. Apart from the implementation of the models and tools, a thorough treatment of the theoretical backgrounds is presented. Part 2 of this report presents a part of an autopilot design process for the 'Beaver' aircraft, which clearly demonstrates the power and flexibility of the AACS design environment from part 1. Evaluations of all longitudinal and lateral control laws by means of nonlinear simulations are treated in detail. A floppy disk containing all relevant MATLAB programs and SIMULINK models is provided as a supplement.

40 CFR 131.34 - Kansas.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Contact Recreation Basin: Solomon Subbasin: Upper North Fork Solomon Ash Creek 10260011 24 Primary Contact... Recreation Subbasin: Lower North Fork Solomon Beaver Creek 10260012 10 Primary Contact Recreation...

40 CFR 131.34 - Kansas.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Contact Recreation Basin: Solomon Subbasin: Upper North Fork Solomon Ash Creek 10260011 24 Primary Contact... Recreation Subbasin: Lower North Fork Solomon Beaver Creek 10260012 10 Primary Contact Recreation...

40 CFR 131.34 - Kansas.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Contact Recreation Basin: Solomon Subbasin: Upper North Fork Solomon Ash Creek 10260011 24 Primary Contact... Recreation Subbasin: Lower North Fork Solomon Beaver Creek 10260012 10 Primary Contact Recreation...

40 CFR 131.34 - Kansas.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Contact Recreation Basin: Solomon Subbasin: Upper North Fork Solomon Ash Creek 10260011 24 Primary Contact... Recreation Subbasin: Lower North Fork Solomon Beaver Creek 10260012 10 Primary Contact Recreation...

Evaluation of the precipitation-runoff modeling system, Beaver Creek basin, Kentucky

USGS Publications Warehouse

Bower, D.E.

1985-01-01

The Precipitation Runoff Modeling System (PRMS) was evaluated with data from Cane branch and Helton Branch in the Beaver Creek basin of Kentucky. Because of previous studies, 10.6 years of record were available to establish a data base for the basin including 60 storms for Cane Branch and 50 storms for Helton Branch. The model was calibrated initially using data from the 1956-58 water years. Runoff predicted by the model was 94.7% of the observed runoff at Cane Branch (mined area) and 96.9% at Helton Branch (unmined area). After the model and data base were modified, the model was refitted to the 1956-58 data for Helton Branch. It then predicted 98.6% of the runoff for the 10.6-year period. The model parameters from Helton Branch were then used to simulate the Cane Branch runoff and discharge. The model predicted 102.6% of the observed runoff at Cane Branch for the 10.6 years. The simulations produced reasonable storm volumes and peak discharges. Sensitivity analysis of model parameters indicated the parameters associated with soil moisture are the most sensitive. The model was used to predict sediment concentration and daily sediment load for selected storm periods. The sediment computations indicated the model can be used to predict sediment concentrations during storm events. (USGS)

Spatial patterns of hydro-social metrics in the Northeastern United States from the Colonial Era through the Industrial Revolution (1600-1920)

NASA Astrophysics Data System (ADS)

Witherell, B. B.; Bain, D. J.; Salant, N.; Aloysius, N. R.

2009-12-01

Humans impact the hydrologic cycle at local, regional and global scales. Understanding how spatial patterns of human water use and hydrologic impact have changed over time is important to future water management in an era of increasing water constraints and globalization of high water-use resources. This study investigates spatial dependence and spatial patterns of hydro-social metrics for the Northeastern United States from 1600 to 1920 through the use of spatial statistical techniques. Several relevant hydro-social metrics, including water residence time, surface water storage (natural and human engineered) and per capita water availability, are analyzed. This study covers a region and period of time that saw significant population growth, landscape change, and industrial growth. These changes had important impacts on water availability. Although some changes such as the elimination of beavers, and the resulting loss of beaver ponds on low-order streams, are felt at a regional scale, preliminary analysis indicates that humans responded to water constraints by acting locally (e.g., mill ponds for water power and water supply reservoirs for public health). This 320-year historical analysis of spatial patterns of hydro-social metrics provides unique insight into long-term changes in coupled human-water systems.

75 FR 45679 - Oklahoma Disaster #OK-00043

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-03

.../26/2010. Incident: Severe Storms, Tornadoes, Straight-line Winds, and Flooding. Incident Period: 06...: Primary Counties: Beaver, Cimarron, Lincoln, Logan, Major, Oklahoma, Texas. The Interest Rates are...

The effect of beaver ponds on water quality in rural coastal plain streams

USGS Publications Warehouse

Bason, Christopher W.; Kroes, Daniel; Brinson, Mark M.

2017-01-01

We compared water-quality effects of 13 beaver ponds on adjacent free-flowing control reaches in the Coastal Plain of rural North Carolina. We measured concentrations of nitrate, ammonium, soluble reactive phosphorus (SRP), and suspended sediment (SS) upstream and downstream of paired ponds and control reaches. Nitrate and SS concentrations decreased, ammonium concentrations increased, and SRP concentrations were unaffected downstream of the ponds and relative to the control reaches. The pond effect on nitrate concentration was a reduction of 112 ± 55 μg-N/L (19%) compared to a control-reach—influenced reduction of 28 ± 17 μg-N/L. The pond effect on ammonium concentration was an increase of 9.47 ± 10.9 μg-N/L (59%) compared to the control-reach—influenced reduction of 1.49 ± 1.37 μg-N/L. The pond effect on SS concentration was a decrease of 3.41 ± 1.68 mg/L (40%) compared to a control-reach—influenced increase of 0.56 ± 0.27 mg/L. Ponds on lower-order streams reduced nitrate concentrations by greater amounts compared to those in higher-order streams. Older ponds reduced SS concentrations by greater amounts compared to younger ponds. The findings of this study indicate that beaver ponds provide water-quality benefits to rural Coastal Plain streams by reducing concentrations of nitrate and suspended sediment.

Tularemia, plague, yersiniosis, and Tyzzer’s disease in wild rodents and lagomorphs in Canada: A review

PubMed Central

Wobeser, Gary; Campbell, G. Douglas; Dallaire, André; McBurney, Scott

2009-01-01

Information related to infection of wild rodents or lagomorphs in Canada by Francisella tularensis, Yersinia pestis, other Yersinia spp., and Clostridium piliforme was searched for this study. Reports on tularemia in humans linked to these species came from diagnostic databases, literature, wildlife health specialists, and public health agencies. Tularemia has been diagnosed in 8 species of wild rodent and 2 species in the genus Lepus in Canada. Tularemia occurred in wild animals, or in humans associated with these species, in all jurisdictions except the Yukon and Nunavut. Tularemia was diagnosed most frequently in beaver, muskrats, and snowshoe hares, and although tularemia is closely linked to cottontail rabbits in the USA, it has not been reported in cottontails in Canada. Tularemia in humans was associated with muskrats and hares more commonly than with beaver. Plague was diagnosed in bushy-tailed woodrats in British Columbia in 1988. Based on surveys, Y. pestis may occur enzootically in southern Alberta, Saskatchewan, and British Columbia. Infection with Yersinia pseudotuberculosis and Y. enterocolitica has been diagnosed in beaver, muskrats, and snowshoe hares in many provinces. Tyzzer’s disease has been diagnosed in muskrats in British Columbia, Saskatchewan, Ontario, and Quebec and in snowshoe hares in Ontario. Infection with these bacteria is likely much more frequent than indicated by diagnostic records. PMID:20190973

Age-related changes in somatic condition and reproduction in the Eurasian beaver: Resource history influences onset of reproductive senescence

PubMed Central

Newman, Chris; Macdonald, David W.

2017-01-01

Using 15 years of data from a stable population of wild Eurasian beavers (Castor fiber), we examine how annual and lifetime access to food resources affect individual age-related changes in reproduction and somatic condition. We found an age-related decline in annual maternal reproductive output, after a peak at age 5–6. Rainfall, an established negative proxy of annual resource availability for beavers, was consistently associated with lower reproductive output for females of all ages. In contrast, breeding territory quality, as a measure of local resource history over reproductive lifetimes, caused differences in individual patterns of reproductive senescence; animals from lower quality territories senesced when younger. Litter size was unrelated to maternal age, although adult body weight increased with age. In terms of resource effects, in poorer years but not in better years, older mothers produced larger offspring than did younger mothers, giving support to the constraint theory. Overall, our findings exemplify state-dependent life-history strategies, supporting an effect of resources on reproductive senescence, where cumulative differences in resource access, and not just reproductive strategy, mediate long-term reproductive trade-offs, consistent with the disposable soma and reproductive restraint theories. We propose that flexible life-history schedules could play a role in the dynamics of populations exhibiting reproductive skew, with earlier breeding opportunities leading to an earlier senescence schedule through resource dependent mechanisms. PMID:29206840

[Visceral and cutaneous larva migrans].

PubMed

Petithory, Jean-Claude

2007-11-30

The syndrome of visceral larva migrans was described for the first time in 1952 by Beaver. He demonstrated that the presence of nematodes larvae, particularly in the liver, were those of Toxocara canis and T. cati. Baylisascaris procyonis, the common racoon ascarid in the U.S.A. can also cause serious diseases in human. Digestive and respiratory clinical symptoms are usually moderate, however severe disease resulting from invasion of the myocardium or the brain has been reported. A blood hypereosinophilia is usually present the first few years after infection. Diagnosis uses serological methods, among them the ELISA test. Ocular larva is also possible with in that case, immunological modifications of the aqueous. Cutaneous larva migrans characterized by a linear, progressing, serpigenous eruption and intense itching is easy to diagnose. Larva migrans is due to dogs, cats and horses helminths. Dogs and cats (referred here as pets) now receive antihelmintitic treatments and parasites are now in decrease.

Reconnaissance of ground-water quality at selected wells in the Beaver Creek watershed, Shelby, Fayette, Tipton, and Haywood counties, West Tennessee, July to August 1992

USGS Publications Warehouse

Fielder, A.M.; Roman-Mas, A. J.; Bennett, M.W.

1994-01-01

A reconnaissance of water-quality conditions of the water-table aquifer in the Beaver Creek watershed and other rural areas of Shelby, Fayette, Tipton, and Haywood Counties, Tennessee, was conducted during July and August 1992. The reconnaissance was conducted by the U.S. Geological Survey, in cooperation with the Tennessee Department of Agriculture and the University of Tennessee Agricultural Extension Service. The report presents data of selected water-quality constituents and properties of water samples collected from 398 domestic wells, located primarily in rural areas. Nitrate concentrations exceeded 10 milligrams per liter in water from 73 of the 398 wells. Fecal coliform and fecal streptococci bacteria were detected in water from 21 and 118 wells, respectively.

Long-term rise of the Water Table in the Northeast US: Climate Variability, Land-Use Change, or Angry Beavers?

NASA Astrophysics Data System (ADS)

Boutt, D. F.

2011-12-01

The scientific evidence that humans are directly influencing the Earth's natural climate is increasingly compelling. Numerous studies suggest that climate change will lead to changes in the seasonality of surface water availability thereby increasing the need for groundwater development to offset those shortages. Research suggests that the Northeast region of the U.S. is experiencing significant changes to its' natural climate and hydrologic systems. Previous analysis of a long-term regional compilation of the water table response to the last 60 years of climate variability in New England documented a wide range of variability. The investigation evaluated the physical mechanisms, natural variability and response of aquifers in New England using 100 long term groundwater monitoring stations with 20 or more years of data coupled with 67 stream gages, 75 precipitation stations, and 43 temperature stations. Groundwater trends were calculated as normalized anomalies and analyzed with respect to regional compiled precipitation, temperature, and streamflow anomalies to understand the sensitivity of the aquifer systems to change. Interestingly, a trend and regression analysis demonstrate that water level fluctuations are producing statistically significant results with increasing water levels over at least the past thirty years at most (80 out of 100) well sites. In this contribution we investigate the causal mechanisms behind the observed ground water level trends using site-by-site land-use change assessments, cluster analysis, and spatial analysis of beaver populations (a possible proxy for beaver activity). Regionally, average annual precipitation has been slightly increasing since 1900, with 95% of the stations having statistically significant positive trends. Despite this, no correlation is observed between the magnitude of the annual precipitation trends and the magnitude of the groundwater level changes. Land-use change throughout the region has primarily taken place in and around existing urban centers with an overall increase in the percentage of forested land. Individual analysis of well sites in areas with documented land-use change from agriculture and forested land cover to urban land use suggests a positive correlation with increasing water levels. Recently, beaver populations been begun to rise that has led to local increases in wetland areas. These regions also show a high positive correlation to the magnitude of water table rise. Local factors such as land-use change and beaver activity appear to overprint and mask the impact of consistent increases in annual precipitation. Rising water tables have major implications for not only water management but also the agriculture, forestry, fishing, and tourism industries as they all depend on the quantity and quality of water resources of the region.

49. AUXILARY CHAMBER, EAST SIDE AIRLOCK LOOKING SOUTHEAST FROM INTERIOR ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

49. AUXILARY CHAMBER, EAST SIDE AIRLOCK LOOKING SOUTHEAST FROM INTERIOR (LOCATION HHH) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

78 FR 25462 - Oklahoma; Major Disaster and Related Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-01

... adversely affected by this major disaster: Alfalfa, Beaver, Beckham, Blaine, Custer, Dewey, Ellis, Garfield... Assistance. Dewey and Ellis Counties for snow assistance under the Public Assistance program for any...

33. FUEL HANDLING BUILDING (LOCATION A), INTERIOR LOOKING NORTH FROM ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

33. FUEL HANDLING BUILDING (LOCATION A), INTERIOR LOOKING NORTH FROM ABOVE CLEAN ROOM - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

50. BOILER CHAMBER No. 1, LOOKING SOUTHEAST BETWEEN CHAMBER AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

50. BOILER CHAMBER No. 1, LOOKING SOUTHEAST BETWEEN CHAMBER AND ENCLOSURE (LOCATION III) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

74. ERECTION AND WELDING OF WEST BOILER CHAMBER, DECEMBER 21, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

74. ERECTION AND WELDING OF WEST BOILER CHAMBER, DECEMBER 21, 1955 (LOOKING NORTHEAST) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

Introduction to the special issue on discontinuity of fluvial systems

NASA Astrophysics Data System (ADS)

Burchsted, Denise; Daniels, Melinda; Wohl, Ellen E.

2014-01-01

Fluvial systems include natural and human-created barriers that modify local base level; as such, these discontinuities alter the longitudinal flux of water and sediment by storing, releasing, or changing the flow path of those materials. Even in the absence of distinct barriers, fluvial systems are typically discontinuous and patchy. The size of fluvial discontinuities ranges across scales from 100 m, such as riffles, to 104 m, such as lava dams or major landslides. The frequency of occurrence appears to be inversely related to size, with creation and failure of the small features, such as beaver dams, occurring on a time scale of 100 to 101 years and a frequency of occurrence at scales as low as 101 m. In contrast, larger scale discontinuities, such as lava dams, can last for time scales up to 105 years and have a frequency of occurrence of approximately 104 m. The heterogeneity generated by features is an essential part of river networks and should be considered as part of river management. Therefore, we suggest that "natural" dams are a useful analog for human dams when evaluating options for river restoration. This collection of papers on the studies of natural dams includes bedrock barriers, log jams and beaver dams. The collection also addresses the discontinuity generated by a floodplain — in the absence of an obvious barrier in the channel — and tools for evaluation of riverbed heterogeneity. It is completed with a study of impact of human dams on floodplain sedimentation. These papers will help geomorphologists and river managers understand the factors that control river heterogeneity across scales and around the world.

55. BOILER CHAMBER No. 1, LOOP B, STEAM DRUM AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

55. BOILER CHAMBER No. 1, LOOP B, STEAM DRUM AND DOWNCOMERS LOOKING EAST (LOCATION LLL) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

66. TURBINE BUILDING (LOCATION N), FIRST LEVEL, B AND D ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

66. TURBINE BUILDING (LOCATION N), FIRST LEVEL, B AND D LOOP STEAM HEATERS FROM NORTH - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

61. BOILER CHAMBER No. 2, LOOKING SOUTHWEST BETWEEN CHAMBER AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

61. BOILER CHAMBER No. 2, LOOKING SOUTHWEST BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION PPP) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

67. TURBINE BUILDING (LOCATION N), FIRST LEVEL, B AND D ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

67. TURBINE BUILDING (LOCATION N), FIRST LEVEL, B AND D LOOP STEAM HEATERS FROM NORTHWEST - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

63. REACTOR CHAMBER (BASF) FROM NORTH SHOWING NEUTRON SHIELD TANK ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

63. REACTOR CHAMBER (BASF) FROM NORTH SHOWING NEUTRON SHIELD TANK AND REACTOR PIPING (LOCATION RRR) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

72. VISITOR'S CENTER, MODEL OF BOILER CHAMBER, AUXILIARY CHAMBER, REACTOR ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

72. VISITOR'S CENTER, MODEL OF BOILER CHAMBER, AUXILIARY CHAMBER, REACTOR AND CANAL (LOCATION T) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

29. MAIN CONTROL ROOM, PANELS WEST OF MAIN CONTROL AREA, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

29. MAIN CONTROL ROOM, PANELS WEST OF MAIN CONTROL AREA, LOOKING SOUTH (LOCATION Q) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

28. MAIN CONTROL ROOM, PANELS WEST OF MAIN CONTROL AREA, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

28. MAIN CONTROL ROOM, PANELS WEST OF MAIN CONTROL AREA, LOOKING NORTH (LOCATION Q) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

124. TV MESSAGE FROM WHITE HOUSE AUTHORIZING LWBR POWER INCREASE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

124. TV MESSAGE FROM WHITE HOUSE AUTHORIZING LWBR POWER INCREASE TO 100%, DECEMBER 2, 1977 - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

3. Historic American Buildings Survey W. Gould White, Photographer March ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. Historic American Buildings Survey W. Gould White, Photographer March 30, 1936 DETAIL OF BRACED ARCH CONSTRUCTION - Smith's Covered Bridge, Beaver Valley, spanning Brandywine River, Granogue, New Castle County, DE

Colonization of steelhead in a natal stream after barrier removal

USGS Publications Warehouse

Weigel, Dana E.; Connolly, Patrick J.; Martens, Kyle D.; Powell, Madison S.

2013-01-01

Colonization of vacant habitats is an important process for supporting the long-term persistence of populations and species. We used a before–after experimental design to follow the process of colonization by steelhead Oncorhynchus mykiss (anadromous Rainbow Trout) at six monitoring sites in a natal stream, Beaver Creek, after the modification or removal of numerous stream passage barriers. Juvenile O. mykiss were collected at monitoring sites by using a backpack electrofisher. Passive integrated transponder tags and instream tag reading stations were used in combination with 16 microsatellite markers to determine the source, extent, and success of migrant O. mykiss after implementation of the barrier removal projects. Steelhead migrated into the study area during the first spawning season after passage was established. Hatchery steelhead, although comprising more than 80% of the adult returns to the Methow River basin, constituted a small proportion (23%) of the adult O. mykiss colonizing the study area. Adult steelhead and fluvial Rainbow Trout entered the stream during the first spawning season after barrier removal and were passing the uppermost tag reader (12 km upstream from the mouth) 3–4 years later. Parr that were tagged in Beaver Creek returned as adults, indicating establishment of the anadromous life history in the study area. Population genetic measures at the lower two monitoring sites (lower 4 km of Beaver Creek) significantly changed within one generation (4–5 years). Colonization and expansion of steelhead occurred more slowly than expected due to the low number of adults migrating into the study area.

A new species of Diapus Chapuis from South-West China and North Thailand (Coleoptera: Curculionidae: Platypodinae).

PubMed

Knížek, M; Beaver, R A; Liu, L-Y

2015-12-16

The genus Diapus Chapuis was erected (Chapuis 1865) for four species of pinhole borer (Curculionidae: Platypodinae) from the Oriental region and New Guinea. It was distinguished from other platypodine genera primarily by the widely separated procoxae (Chapuis 1865). Hopkins (1914) designated Diapus quadrispinatus Chapuis, 1865 as the type species of the genus. The genus is currently placed in the platypodine tribe Tesserocerini, subtribe Diapodina (Alonso-Zarazaga & Lyal 2009). Only two genera are included in the Diapodina, Diapus and Genyocerus Motschulsky (Alonso-Zarazaga & Lyal 2009, Jordal 2015). Diapus is distinguished from Genyocerus by the following characters (Wood 1993, Beaver & Liu 2007): 1. In Diapus, the scutellum is narrower and more sunken, not flush with the elytral surface posteriorly as it is in Genyocerus. 2. The mycangial pores of Diapus are sometimes fused to form a transverse or crescentic bar on each side of the midline of the pronotum. This does not occur in Genyocerus. 3. The antennal club of Diapus sometimes has a median testaceous strip lacking sensillae on the anterior face. This strip is never present in Genyocerus. 4. The males of Diapus never possess a membranous extension of the apical margin of the fourth abdominal ventrite, present in some species of Genyocerus. 5. The females of Diapus often bear deciduous mandibular appendages, which are never present in Genyocerus (Beaver & Liu 2007).

The anatomy of an anomaly. [data on LANDSAT multispectral band scanning in Wyoming

NASA Technical Reports Server (NTRS)

Short, N. M.; Marrs, R. W.

1975-01-01

An anomalous tonal pattern, apparently associated with the Beaver Creek oil field in central Wyoming, was identified using an MSS Band 5 to 4 ratio image made from digital LANDSAT data. This pattern was attributed to an increase in iron with rocks and/or soils which might have resulted from escaping hydrocarbons. The nature of this anomaly was investigated by producing several different combinations of band ratios and by conducting appropriate field studies. The results indicated (1) the existence of a well-defined oval feature related to exposure of iron-cemented red sandstones in a badlands topography, (2) a broader iron-influenced anomaly surrounding this feature, and (3) a spectral response of the rocks, soils, and alluvium making up this iron-colored surface that is readily distinguishable from that of iron-rich reddish Chugwater siltstones exposed in nearby anticlines. The general pattern of the broad anomaly extending beyond the Beaver Creek field is controlled by several factors including variations in vegetation (mainly sage and tall grasses), soil composition and moisture, and topography in addition to variations in iron content of the rock materials. From the available evidence, there is no provable correlation between the oval or the broad anomalies and the distribution of petroleum-producing structures or possible surface alteration effects related to uranium deposits known to occur within this region.

A Whole-Genome Screen of a Quantitative Trait of Age-Related Maculopathy in Sibships from the Beaver Dam Eye Study

PubMed Central

Schick, James H.; Iyengar, Sudha K.; Klein, Barbara E.; Klein, Ronald; Reading, Karlie; Liptak, Rachel; Millard, Christopher; Lee, Kristine E.; Tomany, Sandra C.; Moore, Emily L.; Fijal, Bonnie A.; Elston, Robert C.

2003-01-01

Age-related maculopathy (ARM) is a leading cause of visual impairment among the elderly in Western populations. To identify ARM-susceptibility loci, we genotyped a subset of subjects from the Beaver Dam (WI) Eye Study and performed a model-free genomewide linkage analysis for markers linked to a quantitative measure of ARM. We initially genotyped 345 autosomal markers in 325 individuals (N=263 sib pairs) from 102 pedigrees. Ten regions suggestive of linkage with ARM were observed on chromosomes 3, 5, 6, 12, 15, and 16. Prior to fine mapping, the most significant regions were an 18-cM region on chromosome 12, near D12S1300 (P=.0159); a region on chromosome 3, near D3S1763, with a P value of .0062; and a 6-cM region on chromosome 16, near D16S769, with a P value of .0086. After expanding our analysis to include 25 additional fine-mapping markers, we found that a 14-cM region on chromosome 12, near D12S346 (located at 106.89 cM), showed the strongest indication of linkage, with a P value of .004. Three other regions, on chromosomes 5, 6, and 15, that were nominally significant at P⩽.01 are also appropriate for fine mapping. PMID:12717633

60. BOILER CHAMBER No. 1, D LOOP STEAM GENERATOR AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

60. BOILER CHAMBER No. 1, D LOOP STEAM GENERATOR AND MAIN COOLANT PUMP LOOKING NORTHEAST (LOCATION OOO) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

48. AUXILIARY CHAMBER (EAST END), VIEW LOOKING EAST SHOWING ELECTRICAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

48. AUXILIARY CHAMBER (EAST END), VIEW LOOKING EAST SHOWING ELECTRICAL PENETRATION AND AIR LOCK (LOCATION GGG) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

41. AUXILIARY CHAMBER, CONCRETE ENCLOSURE CHAMBER AIR LOCK (EXTERIOR), LOOKING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

41. AUXILIARY CHAMBER, CONCRETE ENCLOSURE CHAMBER AIR LOCK (EXTERIOR), LOOKING NORTHEAST FROM SOUTHWEST CORNER (LOCATION AAA) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

4. VIEW LOOKING NORTHWEST OF FUEL HANDLING BUILDING (CENTER), REACTOR ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. VIEW LOOKING NORTHWEST OF FUEL HANDLING BUILDING (CENTER), REACTOR SERVICE BUILDING (RIGHT), MACHINE SHOP (LEFT) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

42. AUXILIARY CHAMBER, VIEW LOOKING EAST FROM WEST END, OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

42. AUXILIARY CHAMBER, VIEW LOOKING EAST FROM WEST END, OF AUXILIARY PIPING, STEAM, FEEDWATER PIPING (LOCATION BBB) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

120. COOLANT LINES TO SIS HEAT EXCHANGER No.1 IN AUXILIARY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

120. COOLANT LINES TO SIS HEAT EXCHANGER No.1 IN AUXILIARY CHAMBER, NOVEMBER 1, 1976 - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

75 FR 71525 - Prevailing Rate Systems; Redefinition of the Chicago, IL; Fort Wayne-Marion, IN; Indianapolis, IN...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-24

... economic impact on a substantial number of small entities because they will affect only Federal agencies... * * * * * PENNSYLVANIA * * * * * PITTSBURGH Survey Area Pennsylvania: Allegheny Beaver Butler Washington Westmoreland...

CROSS TRANSMISSION OF 'GIARDIA'

EPA Science Inventory

Giardia cysts isolated from fecal samples obtained from humans (Homo sapiens), beaver (Castor canadensis), dogs (Canis familiaris), cats (Felis domesticus), bighorn X mouflon sheep (Ovis canadensis X O. musimon), guinea pig (Cavis porcellus), muskrat (Ondatra ziethica) and mule d...

Woodland Detection.

ERIC Educational Resources Information Center

Fischer, Richard B.

1989-01-01

Presents tips on nature observation during a woodland hike in the Adirondacks. Discusses engraver beetles and Dutch elm disease, birds' nests, hornets' nests, caterpillar webs, deer and bear signs, woodpecker holes, red squirrels, porcupine and beaver signs, and galls. (SV)

20. DETAILED OBLIQUE VIEW SOUTHWEST FURNACE 2, SHOWING STEEL FRAME ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. DETAILED OBLIQUE VIEW SOUTHWEST FURNACE 2, SHOWING STEEL FRAME BOXES FOR COUNTERWEIGHTS, AND FURNACE HEATING PIPES AT RIGHT. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

44. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION CCC), ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

44. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION CCC), LOOKING NORTHEAST SHOWING DRAIN PIPE FROM SUMP - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

Grand Lake Saint Marys, Ohio, Survey Report for Flood Control and Allied Purposes. Volume 1.

DTIC Science & Technology

1981-08-01

nuprotected shoreline have reduced the lake depth. A range of structural and, nanatructural flood damage reduction1 usasures wee exmined. Nonstructural masaes ...24 330 Apr 1972 872.67 32 310 Apr 1938 872.42 19 550 Feb 1950 872.42 24 520 Apr 1978 872.17 37 380 Jan 1949 872.08 19 260 Apr 1957 872.08 23 550 Jun...1958 871.92 11 380 May 1933 871.92 5 490 Nov 1972 871.92 9 510 16 . ..... Ie Flood Damages The areas under consideration include Beaver Creek

69. TURBINE BUILDING (LOCATION N), THIRD LEVEL LOOKING NORTHWEST SHOWING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

69. TURBINE BUILDING (LOCATION N), THIRD LEVEL LOOKING NORTHWEST SHOWING BASE OF CONDENSOR AND RIVER WATER OUTLET PIPE - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

35. FUEL HANDLING BUILDING, INTERIOR LOOKING SOUTHEAST SHOWING TRANSFER CANAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

35. FUEL HANDLING BUILDING, INTERIOR LOOKING SOUTHEAST SHOWING TRANSFER CANAL AREA, DEEP STORAGE AREA, FUEL STORAGE PIT (LOCATION BB) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

3. INTAKE CHANNEL LOOKING WEST; DEBRIS FILTER SCREEN IN GATE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. INTAKE CHANNEL LOOKING WEST; DEBRIS FILTER SCREEN IN GATE 2. - Hondius Water Line, 1.6 miles Northwest of Park headquarters building & 1 mile Northwest of Beaver Meadows entrance station, Estes Park, Larimer County, CO

PERSPECTIVE FROM SOUTH SHOWING WEATHERED BOARD AND BATTEN SIDING. NOTE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PERSPECTIVE FROM SOUTH SHOWING WEATHERED BOARD AND BATTEN SIDING. NOTE BRIDGE SITS ON ONE CONCRETEFACED ABUTMENT AND ONE STONE PIER. - Beaverkill Bridge, Spanning Beaver Kill, TR 30 (Craigie Claire Road), Roscoe, Sullivan County, NY

Indian Creek uranium prospects, Beaver County, Utah

USGS Publications Warehouse

Wyant, Donald G.; Stugard, Frederick

1951-01-01

The secondary uranium minerals metatorbernite (?) and autunite (?) were discovered at Indian Creek in the spring of 1950. The deposits, in sec. 26, T. 27 S., R. 6 T., Beaver County, Utah, are 20 miles west of Marysvale, and about three-eighths of a mile east of a quartz monzonite stock. The uranium minerals are sparsely disseminated in argillized and silicified earlier Tertiary Bullion Canyon latite and related volcanic rock beneart, but close to, the contact of the overlying later Tertiary Mount Belknap gray rhyolite. The prospects are in a landslide area where exposures are scarce. Therefore, trend and possible continuity of the altered and the uraniferous zones cannot be established definitely. The occurrence of secondary uranium minerals in beidellite-montmorillonite rock, formed by alteration of earlier Tertiary rocks near a quartz monzonite stock, is similar to that in some of the deposits in the Marysvale uranium district.

Prevalence of agglutinating antibodies to Toxoplasma gondii and Sarcocystis neurona in beavers (Castor canadensis) from Massachusetts

USGS Publications Warehouse

Jordan, C.N.; Kaur, T.; Koenen, K.; DeStefano, S.; Zajac, A.M.; Lindsay, D.S.

2005-01-01

The present study examined the seroprevalence of Toxoplasma gondii and Sarcocystls neurona in a population of beavers (Castor canadensis) from Massachusetts. Sixty-two blood samples were collected during the field seasons over 3 consecutive years from different animals. Blood was collected onto filter paper and shipped to the Department of Biomedical Sciences, Virginia Tech, Blacksburg, Virginia, for parasite testing. The samples were tested at dilutions of 1:25, 1:50, and 1:100 against each parasite antigen by modified agglutination tests to determine whether antibodies to either parasite were present in the blood. Six of 62 samples (10%) were positive for T. gondii, with 2 samples having titers of 1:25 and 4 having titers of 1:50. Four of 62 samples (6%) were positive for S. neurona, with 2 samples having titers of 1:25 and 2 having titers of 1:50. ?? American Society of Pathologists 2005.

Why Can’t Rodents Vomit? A Comparative Behavioral, Anatomical, and Physiological Study

PubMed Central

Horn, Charles C.; Kimball, Bruce A.; Wang, Hong; Kaus, James; Dienel, Samuel; Nagy, Allysa; Gathright, Gordon R.; Yates, Bill J.; Andrews, Paul L. R.

2013-01-01

The vomiting (emetic) reflex is documented in numerous mammalian species, including primates and carnivores, yet laboratory rats and mice appear to lack this response. It is unclear whether these rodents do not vomit because of anatomical constraints (e.g., a relatively long abdominal esophagus) or lack of key neural circuits. Moreover, it is unknown whether laboratory rodents are representative of Rodentia with regards to this reflex. Here we conducted behavioral testing of members of all three major groups of Rodentia; mouse-related (rat, mouse, vole, beaver), Ctenohystrica (guinea pig, nutria), and squirrel-related (mountain beaver) species. Prototypical emetic agents, apomorphine (sc), veratrine (sc), and copper sulfate (ig), failed to produce either retching or vomiting in these species (although other behavioral effects, e.g., locomotion, were noted). These rodents also had anatomical constraints, which could limit the efficiency of vomiting should it be attempted, including reduced muscularity of the diaphragm and stomach geometry that is not well structured for moving contents towards the esophagus compared to species that can vomit (cat, ferret, and musk shrew). Lastly, an in situ brainstem preparation was used to make sensitive measures of mouth, esophagus, and shoulder muscular movements, and phrenic nerve activity–key features of emetic episodes. Laboratory mice and rats failed to display any of the common coordinated actions of these indices after typical emetic stimulation (resiniferatoxin and vagal afferent stimulation) compared to musk shrews. Overall the results suggest that the inability to vomit is a general property of Rodentia and that an absent brainstem neurological component is the most likely cause. The implications of these findings for the utility of rodents as models in the area of emesis research are discussed. PMID:23593236

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brumbaugh, William D.; Cook, Kenneth L.

During the summers of 1975 and 1976, a gravity survey was conducted in the Cove Fort - Sulphurdale KGRA and north Mineral Mountains area, Millard and Beaver counties, Utah. The survey consisted of 671 gravity stations covering an area of about 1300 km{sup 2}, and included two orthogonal gravity profiles traversing the area. The gravity data are presented as a terrain-corrected Bouguer gravity anomaly map with a contour interval of 1 mgal and as an isometric three-dimensional gravity anomaly surface. Selected anomaly separation techniques were applied to the hand-digitized gravity data (at 1-km intervals on the Universal Transverse Mercator grid)more » in both the frequency and space domains, including Fourier decomposition, second vertical derivative, strike-filter, and polynomial fitting analysis, respectively. Residual gravity gradients of 0.5 to 8.0 mgal/km across north-trending gravity contours observed through the Cove Fort area, the Sulphurdale area, and the areas east of the East Mineral Mountains, along the west flanks of the Tushar Mountains, and on both the east and west flanks of the north Mineral Mountains, were attributed to north-trending Basin and Range high-angle faults. Gravity highs exist over the community of Black Rock area, the north Mineral Mountains, the Paleozoic outcrops in the east Cove Creek-Dog Valley-White Sage Flats areas, the sedimentary thrust zone of the southern Payant Range, and the East Mineral Mountains. The gravity lows over north Milford Valley, southern Black Rock Desert, Cunningham Wash, and northern Beaver Valley are separated from the above gravity highs by steep gravity gradients attributed to a combination of crustal warping and faulting. A gravity low with a closure of 2 mgal corresponds with Sulphur Cove, a circular topographic features containing sulphur deposits.« less

46. AUXILIARY CHAMBER (EAST END), LOOKING NORTHWEST AT STEAM AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

46. AUXILIARY CHAMBER (EAST END), LOOKING NORTHWEST AT STEAM AND FEEDWATER PIPING AND PRESSURIZER AND FLASH/BLOWOFF TANK ROOMS (LOCATION EEE) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

78 FR 52600 - Pennsylvania Disaster #PA-00063

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-23

... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13722 and 13723] Pennsylvania Disaster PA... Administrative declaration of a disaster for the Commonwealth of Pennsylvania dated 08/14/2013. Incident: Severe... adversely affected by the disaster: Primary Counties: Lawrence. Contiguous Counties: Pennsylvania: Beaver...

78 FR 30863 - Foreign-Trade Zone 40-Cleveland, Ohio; Application for Reorganization and Expansion Under...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-23

... Beaver Meadow Parkway, Glenwillow; Site 5 (17 acres)--Collinwood Industrial Park, South Waterloo Road and... be so exempted. The application would have no impact on FTZ 40's previously authorized subzones. In...

78 FR 34151 - Notice of Public Hearing: Norfolk Southern Corporation

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-06

... in a public hearing on July 23, 2013. The hearing will be conducted at the Moon Township Building, 1000 Beaver Grade Road, Moon Township, PA 15108. The hearing will begin at 9:00 a.m. Interested parties...

45. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION DDD), ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

45. AUXILIARY CHAMBER BETWEEN CHAMBER AND CONCRETE ENCLOSURE (LOCATION DDD), VIEW LOOKING EAST. LEAD ENCLOSED PIPING IS DRAIN FROM BOILER CHAMBER No. 1 - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

76 FR 35234 - Announcement of Funding Awards for Fiscal Year 2010; Transformation Initiative: Natural...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-16

... funding to support scientific research that makes use of natural experiments to evaluate the impacts of... of Planning and Research, 33 Beaver Street, 20th floor, New York, New York, 10004-2737. Grant: $100...

8. VIEW FROM NORTHWEST OF CONDENSATE STORAGE TANK (LEFT), PRIMARY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. VIEW FROM NORTHWEST OF CONDENSATE STORAGE TANK (LEFT), PRIMARY WATER STORAGE TANK (CENTER), CANAL WATER STORAGE TANK (RIGHT) (LOCATIONS E,F,D) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

22. DETAIL OBLIQUE VIEW NORTHWEST OF FURNACE 2, SHOWING GENERAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. DETAIL OBLIQUE VIEW NORTHWEST OF FURNACE 2, SHOWING GENERAL CONSTRUCTION. CONCRETE PAD AT LEFT IS SITE OF FORMER FURNACE USED TO HEAT URANIUM BILLETS. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

Heterogeneity in a Suburban River Network: Understanding the Impact of Fluvial Wetlands on Dissolved Oxygen and Metabolism in Headwater Streams

NASA Astrophysics Data System (ADS)

Cain, J. S.; Wollheim, W. M.; Sheehan, K.; Lightbody, A.

2014-12-01

Low dissolved oxygen content in rivers threatens fish populations, aquatic organisms, and the health of entire ecosystems. River systems with high fluvial wetland abundance and organic matter, may result in high metabolism that in conjunction with low re-aeration rates, lead to low oxygen conditions. Increasing abundance of beaver ponds in many areas may exacerbate this phenomenon. This research aims to understand the impact of fluvial wetlands, including beaver ponds, on dissolved oxygen (D.O.) and metabolism throughout the headwaters of the Ipswich R. watershed, MA, USA. In several fluvial wetland dominated systems, we measured diel D.O. and metabolism in the upstream inflow, the surface water transient storage zones of fluvial wetland sidepools, and at the outflow to understand how the wetlands modify dissolved oxygen. D.O. was also measured longitudinally along entire surface water flow paths (x-y km long) to determine how low levels of D.O. propagate downstream. Nutrient samples were also collected to understand how their behavior was related to D.O. behavior. Results show that D.O. in fluvial wetlands has large swings with periods of very low D.O. at night. D.O. swings were also seen in downstream outflow, though lagged and somewhat attenuated. Flow conditions affect the level of inundation and the subsequent effects of fluvial wetlands on main channel D.O.. Understanding the D.O. behavior throughout river systems has important implications for the ability of river systems to remove anthropogenic nitrogen.

Beaver Fever: Whole-Genome Characterization of Waterborne Outbreak and Sporadic Isolates To Study the Zoonotic Transmission of Giardiasis.

PubMed

Tsui, Clement K-M; Miller, Ruth; Uyaguari-Diaz, Miguel; Tang, Patrick; Chauve, Cedric; Hsiao, William; Isaac-Renton, Judith; Prystajecky, Natalie

2018-04-25

Giardia causes the diarrheal disease known as giardiasis; transmission through contaminated surface water is common. The protozoan parasite's genetic diversity has major implications for human health and epidemiology. To determine the extent of transmission from wildlife through surface water, we performed whole-genome sequencing (WGS) to characterize 89 Giardia duodenalis isolates from both outbreak and sporadic infections: 29 isolates from raw surface water, 38 from humans, and 22 from veterinary sources. Using single nucleotide variants (SNVs), combined with epidemiological data, relationships contributing to zoonotic transmission were described. Two assemblages, A and B, were identified in surface water, human, and veterinary isolates. Mixes of zoonotic assemblages A and B were seen in all the community waterborne outbreaks in British Columbia (BC), Canada, studied. Assemblage A was further subdivided into assemblages A1 and A2 based on the genetic variation observed. The A1 assemblage was highly clonal; isolates of surface water, human, and veterinary origins from Canada, United States, and New Zealand clustered together with minor variation, consistent with this being a panglobal zoonotic lineage. In contrast, assemblage B isolates were variable and consisted of several clonal lineages relating to waterborne outbreaks and geographic locations. Most human infection isolates in waterborne outbreaks clustered with isolates from surface water and beavers implicated to be outbreak sources by public health. In-depth outbreak analysis demonstrated that beavers can act as amplification hosts for human infections and can act as sources of surface water contamination. It is also known that other wild and domesticated animals, as well as humans, can be sources of waterborne giardiasis. This study demonstrates the utility of WGS in furthering our understanding of Giardia transmission dynamics at the water-human-animal interface. IMPORTANCE Giardia duodenalis causes large numbers of gastrointestinal illness in humans. Its transmission through the contaminated surface water/wildlife intersect is significant, and the water-dwelling rodents beavers have been implicated as one important reservoir. To trace human infections to their source, we used genome techniques to characterize genetic relationships among 89 Giardia isolates from surface water, humans, and animals. Our study showed the presence of two previously described genetic assemblages, A and B, with mixed infections detected from isolates collected during outbreaks. Study findings also showed that while assemblage A could be divided into A1 and A2, A1 showed little genetic variation among animal and human hosts in isolates collected from across the globe. Assemblage B, the most common type found in the study surface water samples, was shown to be highly variable. Our study demonstrates that the beaver is a possible source of human infections from contaminated surface water, while acknowledging that theirs is only one role in the complex cycle of zoonotic spread. Mixes of parasite groups have been detected in waterborne outbreaks. More information on Giardia diversity and its evolution using genomics will further the understanding of the epidemiology of spread of this disease-causing protozoan. © Crown copyright 2018.

30. DETAILED FRONTAL VIEW WEST OF EXCAVATION AT SUSPECTED MICA ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

30. DETAILED FRONTAL VIEW WEST OF EXCAVATION AT SUSPECTED MICA PIT, SHOWING SOIL MIXED WITH MICA FLAKES AT REAR, AND DEEPER HOLE OF VIRGIN SOIL AT FRONT. - Vulcan Crucible Steel Company, Building No. 3, 100 First Street, Aliquippa, Beaver County, PA

96. SEED 1 FUEL ASSEMBLY FROM LOCATION L9 BEING REMOVED ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

96. SEED 1 FUEL ASSEMBLY FROM LOCATION L-9 BEING REMOVED FROM REACTOR VESSEL BY MEANS OF FUEL EXTRACTION CRANE, JANUARY 7, 1960 - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

Hydrologic analysis of the proposed Badger-Beaver Creeks Artificial-Recharge Project : Morgan County, Colorado

USGS Publications Warehouse

Burns, Alan W.

1980-01-01

A hydrologic analysis of the proposed Badger-Beaver Creeks artificial-recharge project in Morgan County, Colo., was made with the aid of three digital computer models: A canal-distribution model, a ground-water flow model, and a stream-aquifer model. Statistical summaries of probable diversions from the South Platte River based on a 27-year period of historical flows indicate that an average-annual diversion of 96,000 acre-feet and a median-annual diversion of 43,000 acre-feet would be available. Diversions would sustain water in ponds for waterfowl habitat for an average of about five months per year, with a miximum pond surface area of about 300 acres with the median diversions and a maximum pond surface area of about 1,250 acres at least one-half of the years with the historic diversions. If the annual diversion were 43,000 acre-feet, recharge to the two alluvial aquifers would raise water levels sufficiently to create flowing streams in the channels of Beaver and Badger Creeks while allowing an increase in current ground-water pumping. The only area of significant waterlogging would be along the proposed delivery canal on the west edge of Badger Creek valley. If the total water available were diverted, the aquifer system could not transmit the water fast enough to the irrigation areas to avoid considerable waterlogging in the recharge areas. The impact of the proposed project on the South Platte River basin would be minimal once the ground-water system attained steady-state conditions, but that may take decades with a uniform diversion of the 43,000 acre-feet annually. (USGS)

Contrasting fish assemblages in free-flowing and impounded tributaries to the Upper Delaware River: Implications for conserving biodiversity

USGS Publications Warehouse

Baldigo, Barry P.; Delucia, Mari-Beth; Keller, Walter D.; Schuler, George E.; Apse, Colin D.; Moberg, Tara

2015-01-01

The Neversink River and the Beaver Kill in southeastern New York are major tributaries to the Delaware River, the longest undammed river east of the Mississippi. While the Beaver Kill is free flowing for its entire length, the Neversink River is subdivided by the Neversink Reservoir, which likely affects the diversity of local fish assemblages and health of aquatic ecosystems. The reservoir is an important part of the New York City waster-supply system that provides drinking water to more than 9 million people. Fish population and community data from recent quantitative surveys at comparable sites in both basins were assessed to characterize the differences between free-flowing and impounded rivers and the extent of reservoir effects to improve our capacity to define ecosystems responses that two modified flow-release programs (implemented in 2007 and 2011) should produce in the Neversink River. In general, the continuum of changes in fish assemblages which normally occur between headwaters and mouth was relatively uninterrupted in the Beaver Kill, but disrupted by the mid-basin impoundment in the Neversink River. Fish assemblages were also adversely affected at several acidified sites in the upper Neversink River, but not at most sites assessed herein. The reservoir clearly excluded diadromous species from the upper sub-basin, but it also substantially reduced community richness, diversity, and biomass at several mid-basin sites immediately downstream from the impoundment. There results will aid future attempts to determine if fish assemblages respond to more natural, yet highly regulated, flow regimes in the Neversink River. More important, knowledge gained from this study can help optimize use of valuable water resources while promoting species of special concern, such as American eel (Anguilla rostrata) and conserving biodiversity in Catskill Mountain streams.

10. SETTLING TANK CLEANOUT DOORS, SOUTH SIDE; USED TO CLEAN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. SETTLING TANK CLEAN-OUT DOORS, SOUTH SIDE; USED TO CLEAN DEBRIS FROM SURFACE OF WATER IN SETTLING TANK. - Hondius Water Line, 1.6 miles Northwest of Park headquarters building & 1 mile Northwest of Beaver Meadows entrance station, Estes Park, Larimer County, CO

Tracking the deployment of the integrated metropolitan ITS infrastructure in Pittsburgh, Beaver Valley : FY99 results

DOT National Transportation Integrated Search

1999-01-01

In January 1996, Secretary Pea set a goal of deploying the integrated metropolitan Intelligent Transportation System (ITS) infrastructure in 75 of the nations largest metropolitan areas by 2006. In 1997, the U.S. Department of Transportation ini...

3. OVERALL FRONTAL VIEW NORTH, SOUTH FACADES OF BUILDINGS 2 ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. OVERALL FRONTAL VIEW NORTH, SOUTH FACADES OF BUILDINGS 2 AND 3, RIGHT TO LEFT. NO. 2 HAS AN ALIQUIPPA FORGE SIGN. NO 3 IS THE DOUBLE BUILDING TO THE LEFT. - Vulcan Crucible Steel Company, 100 First Street, Aliquippa, Beaver County, PA

17. INTERIOR VIEW, BASEMENT, LOOKING SOUTHWEST AT THE GEAR PIT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. INTERIOR VIEW, BASEMENT, LOOKING SOUTHWEST AT THE GEAR PIT BELOW THE GRINDING STONES, SHOWING WOODEN COGS ATTACHED TO UNDERGROUND TURBINES. FRICTION DRIVE VISIBLE BEHIND CONTROL BAR (LEFT) WHICH OPERATES SMUT MILL - Schech's Mill, Beaver Creek State Park, La Crescent, Houston County, MN

1. Photocopy of engineering drawing (original in the Office of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Photocopy of engineering drawing (original in the Office of the Cuyahoga County Engineer)--1907 NORTH ROCKY RIVER BRIDGE--PROPOSED DESIGN--REINFORCED CONCRETE: AN ALTERNATIVE DESIGN FOR THE DETROIT AVENUE CROSSING - Rocky River Bridge, Spanning Beaver Dam River, Rocky River, Cuyahoga County, OH

GENOTYPES OF CRYPTOSPORIDIUM INFECTING FUR-BEARING MAMMALS DIFFER FROM THOSE INFECTING HUMANS

EPA Science Inventory

To evaluate the public health significance of wildlife Cryptosporidium spp., five species of small wild mammals (beavers, muskrats, otters, raccoons, and foxes) living in Chesapeake Bay watersheds were examined in this study for the presence of Cryptosporidium spp., using a small...

Mapping wetlands on beaver flowages with 35-mm photography

USGS Publications Warehouse

Kirby, R.E.

1976-01-01

Beaver flowages and associated wetlands on the Chippewa National Forest, north-central Minnesota, were photographed from the ground and from the open side window of a small high-wing monoplane. The 35-mm High Speed Ektachrome transparencies obtained were used to map the cover-type associations visible on the aerial photographs. Nearly vertical aerial photos were rectified by projecting the slides onto a base map consisting ofcontrol points located by plane-table survey. Maps were prepared by tracing the recognizable stands of vegetation in the rectified projection at the desired map scale. Final map scales ranging from 1:260 to 1:571 permitted identification and mapping of 26 cover-type associations on 10 study flowages in 1971. This cover-mapping technique was economical and substituted for detailed ground surveys. Comparative data from 10 flowages were collected serially throughout the entire open-water season. Although developed for analysis of waterfowl habitat, the technique has application to other areas of wildlife management and ecological investigation.

Floatplane Source Noise Measurements : Summary of Measurements, Data and Analyses for the Cessna 182S Skylane and De Havilland Canada DHC-2 Beaver.

DOT National Transportation Integrated Search

2012-01-31

The U.S. Department of Transportation, John A. Volpe National Transportation Systems Center (Volpe Center), Environmental Measurement and Modeling Division, provides technical support to the Federal Aviation Administration (FAA), with the cooperation...

30 CFR 46.3 - Training plans.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING TRAINING AND..., National Mine Health and Safety Academy, 1301 Airport Road, Beaver, WV 25813-9426, Telephone: (304) 256... responsible for the health and safety training at the mine. This person may be the production-operator or...

13. INTERIOR VIEW, FIRST FLOOR SHOWING THE ELEVATORS FEEDING GRAIN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. INTERIOR VIEW, FIRST FLOOR SHOWING THE ELEVATORS FEEDING GRAIN FROM THE SECOND FLOOR TO THE GRINDING STONES, WITH GRAIN ELEVATORS IN BACKGROUND (NOTE OUTLINE ON THE FLOOR WHERE ROLLER MILLS WERE ORIGINALLY PLACED) - Schech's Mill, Beaver Creek State Park, La Crescent, Houston County, MN

Self-Report Measures of Family Competence.

ERIC Educational Resources Information Center

Green, Robert G.

1987-01-01

Describes and compares two self-report measures of family competence: the Family Awareness Scales (FAS) (Green and Kolevzon, late 1970s) and the Self-Report Family Inventory (SFI) (Beavers, 1983). Discusses reliability and validity. Their focus on the "insider" (family member) is different from the traditional examination of family…

40 CFR 52.2027 - Approval status of Pennsylvania's Generic NOX and VOC RACT Rules.

Code of Federal Regulations, 2012 CFR

2012-07-01

... through 129.95 (see § 52.2020 (c)(129)) as those regulations apply to the Pittsburgh-Beaver Valley area... its approval of 25 PA Code of Regulations, Chapter 129.91 through 129.95 [see § 52.2020 (c)(129)] as...

40 CFR 52.2027 - Approval status of Pennsylvania's Generic NOX and VOC RACT Rules.

Code of Federal Regulations, 2013 CFR

2013-07-01

... through 129.95 (see § 52.2020 (c)(129)) as those regulations apply to the Pittsburgh-Beaver Valley area... its approval of 25 PA Code of Regulations, Chapter 129.91 through 129.95 [see § 52.2020 (c)(129)] as...

Spatial variation in population dynamics of Sitka mice in floodplain forests.

Treesearch

T.A. Hanley; J.C. Barnard

1999-01-01

Population dynamics and demography of the Sitka mouse, Peromyscus keeni sitkensis, were studied by mark-recapture live-trapping over a 4-year period in four floodplain and upland forest habitats: old-growth Sitka spruce (Picea sitchensis) floodplain; red alder (Alnus rubra) floodplain; beaver-pond...

78 FR 28780 - Proposed Flood Elevation Determinations for Beaver County, Pennsylvania (All Jurisdictions)

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-16

..., identified by Docket No. FEMA-B- 1147 to Luis Rodriguez, Chief, Engineering Management Branch, Federal..., DC 20472, (202) 646-4064, or (email) Luis[email protected] . FOR FURTHER INFORMATION CONTACT: Luis Rodriguez, Chief, Engineering Management Branch, Federal Insurance and Mitigation Administration...

2. VIEW LOOKING EAST AT STEPS AND LAND WALL (GEOGRAPHIC ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. VIEW LOOKING EAST AT STEPS AND LAND WALL (GEOGRAPHIC CENTER OF THE LOCK COMPLEX), FROM THE OHIO RIVER. - Ohio Slack Water Dams, Lock & Dam No. 4, East bank of Ohio River at mile point 18.6, along State Route 65, Ambridge, Beaver County, PA

Mechanisms and Magnitude of Cenozoic Crustal Extension in the Vicinity of Lake Mead, Nevada and the Beaver Dam Mountains, Utah: Geochemical, Geochronological,Thermochronological and Geophysical Constraints

NASA Astrophysics Data System (ADS)

Almeida, Rafael V.

The central Basin and Range Province of Nevada and Utah was one of the first areas in which the existence of widespread low-angle normal faults or detachments was first recognized. The magnitude of associated crustal extension is estimated by some to be large, in places increasing original line lengths by as much as a factor of four. However, rock mechanics experiments and seismological data cast doubt on whether these structures slipped at low inclination in the manner generally assumed. In this dissertation, I review the evidence for the presence of detachment faults in the Lake Mead and Beaver Dam Mountains areas and place constraints on the amount of extension that has occurred there since the Miocene. Chapter 1 deals with the source-provenance relationship between Miocene breccias cropping out close to Las Vegas, Nevada and their interpreted source at Gold Butte, currently located 65 km to the east. Geochemical, geochronological and thermochronological data provide support for that long-accepted correlation, though with unexpected mismatches requiring modification of the original hypothesis. In Chapter 2, the same data are used to propose a refinement of the timing of ~1.45 Ga anorogenic magmatism, and the distribution of Proterozoic crustal boundaries. Chapter 3 uses geophysical methods to address the subsurface geometry of faults along the west flank of the Beaver Dam Mountains of southwestern Utah. The data suggest that the range is bounded by steeply inclined normal faults rather than a regional-scale detachment fault. Footwall folding formerly ascribed to Miocene deformation is reinterpreted as an expression of Cretaceous crustal shortening. Fission track data presented in Chapter 4 are consistent with mid-Miocene exhumation adjacent to high-angle normal faults. They also reveal a protracted history dating back to the Pennsylvanian-Permian time, with implications for the interpretation of other basement-cored uplifts in the region. A key finding of this dissertation is that the magnitude of crustal extension in this region has been overestimated. The pre-extensional width was increased by a factor of two across Lake Mead, through a combination of high-angle normal faulting and strike-slip deformation. Data from the transect across the Beaver Dam Mountains suggest substantially less extension, with the difference accommodated for the most part by displacement on the intervening Las Vegas Valley Shear Zone. The Colorado Plateau-Basin and Range transition zone may be a long-lived tectonic boundary where this assumption may be especially ill-suited.

Biotransformation of tributyltin to tin in freshwater river-bed sediments contaminated by an organotin release

USGS Publications Warehouse

Landmeyer, J.E.; Tanner, T.L.; Watt, B.E.

2004-01-01

The largest documented release of organotin compounds to a freshwater river system in the United States occurred in early 2000 in central South Carolina. The release consisted of an unknown volume of various organotin compounds such tetrabutyltin (TTBT), tributyltin (TBT), tetraoctyltin (TTOT), and trioctyl tin (TOT) and resulted in a massive fish kill and the permanent closures of a municipal wastewater treatment plant and a local city's only drinking-water intake. Initial sampling events in 2000 and 2001 indicated that concentrations of the ecologically toxic TTBT and TBT were each greater than 10 000 ??g/kg in surface-water bed sediments in depositional areas, such as lakes and beaver ponds downstream of the release. Bed-sediment samples collected between 2001 and 2003, however, revealed a substantial decrease in bed-sediment organotin concentrations and an increase in concentrations of degradation intermediate compounds. For example, in bed sediments of a representative beaver pond located about 1.6 km downstream of the release, total organotin concentrations [the sum of TTBT, TBT, and the TBT degradation intermediates dibutyltin (DBT) and monobutyltin (MBT)] decreased from 38 670 to 298 ??g/kg. In Crystal Lake, a large lake about 0.4 km downstream from the beaver pond, total organotin concentrations decreased from 28 300 to less than 5 ??g/kg during the same time period. Moreover, bed-sediment inorganic tin concentrations increased from pre-release levels of less than 800 to 32 700 ??g/kg during this time. These field data suggest that the released organotin compounds, such as TBT, are being transformed into inorganic tin by bed-sediment microbial processes. Microcosms were created in the laboratory that contained bed sediment from the two sites and were amended with tributyltin (as tributyltin chloride) under an ambient air headspace and sacrificially analyzed periodically for TBT, the biodegradation intermediates DBT and MBT, and tin. TBT concentrations decreased faster [half-life (t1/2) = 28 d] in the organic-rich sediments (21.5%) that characterized the beaver pond as compared to the slower (t1/2 = 78 d) degradation rate in the sandy, organic-poor, sediments (0.43%) of Crystal Lake. Moreover, the concentration of inorganic tin increased in microcosms containing bed sediments from both locations. These field and laboratory results suggest that biotransformation of the released organotins, in particular the ecologically detrimental TBT, does occur in this fresh surface-water system impacted with high concentrations of neat organotin compounds.

40 CFR 52.2038 - Rate of Progress Plans: Ozone.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 5 2012-07-01 2012-07-01 false Rate of Progress Plans: Ozone. 52.2038... Progress Plans: Ozone. (a) EPA grants full approval to Pennsylvania's 15 Percent Rate of Progress Plan for the Pittsburgh-Beaver Valley ozone nonattainment area, submitted by the Secretary of the Pennsylvania...

40 CFR 52.2038 - Rate of Progress Plans: Ozone.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Rate of Progress Plans: Ozone. 52.2038... Progress Plans: Ozone. (a) EPA grants full approval to Pennsylvania's 15 Percent Rate of Progress Plan for the Pittsburgh-Beaver Valley ozone nonattainment area, submitted by the Secretary of the Pennsylvania...

40 CFR 52.2038 - Rate of Progress Plans: Ozone.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 5 2013-07-01 2013-07-01 false Rate of Progress Plans: Ozone. 52.2038... Progress Plans: Ozone. (a) EPA grants full approval to Pennsylvania's 15 Percent Rate of Progress Plan for the Pittsburgh-Beaver Valley ozone nonattainment area, submitted by the Secretary of the Pennsylvania...

40 CFR 52.2038 - Rate of Progress Plans: Ozone.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 4 2011-07-01 2011-07-01 false Rate of Progress Plans: Ozone. 52.2038... Progress Plans: Ozone. (a) EPA grants full approval to Pennsylvania's 15 Percent Rate of Progress Plan for the Pittsburgh-Beaver Valley ozone nonattainment area, submitted by the Secretary of the Pennsylvania...

40 CFR 52.2038 - Rate of Progress Plans: Ozone.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 5 2014-07-01 2014-07-01 false Rate of Progress Plans: Ozone. 52.2038... Progress Plans: Ozone. (a) EPA grants full approval to Pennsylvania's 15 Percent Rate of Progress Plan for the Pittsburgh-Beaver Valley ozone nonattainment area, submitted by the Secretary of the Pennsylvania...

Innovation Abstracts, Volume IV, Numbers 1-36.

ERIC Educational Resources Information Center

Watkins, Karen, Ed.

1982-01-01

Brief, two-page abstracts are provided on 36 educational topics of interest to community college faculty, administrators, and staff. The topics covered are: (1) a student retention technique; (2) educational productivity and quality; (3) competency-based adult education; (4) part-time faculty; (5) Beaver College's (Pennsylvania) writing across the…

Network Centric Operations NCO Case Study. The British Approach to Low-Intensity Operations: Part I

DTIC Science & Technology

2007-02-12

Army’s institutional memory of jungle warfare (during WW2 ) had dissipated by 1948. Nonetheless, individuals within the Army who had experienced such...with a specially stabilised TV camera mounting. It also fitted infrared surveillance systems to its Beaver spotter planes, which helped detect

75 FR 65371 - Klamath Marsh National Wildlife Refuge, Klamath County, OR

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-22

... impact. SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce the availability of the Final Comprehensive Conservation Plan (CCP) and Finding of No Significant Impact (FONSI) for the Klamath Marsh... rails, Oregon spotted frogs, red-naped sapsuckers, pygmy nuthatches, bald eagles, beaver, and red band...

Assess the presence and potential habitat for reintroduction of priority freshwater mussel species in the Shenango River.

DOT National Transportation Integrated Search

2010-12-31

The Shenango River is a principal tributary of the Beaver River, which may provide an opportunity for the relocation of clubshell and northern riffleshell. These federally listed mussels and other species of concern may be present in the Shenango Riv...

76 FR 74717 - Suspension of Community Eligibility

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-01

..., Dec. 2, 2011 Dec. 2, 2011. Clarion County. 1979, Emerg; January 17, 1985, Reg; December 2, 2011, Susp. Beaver, Township of, 422362 October 26, ......do Do. Clarion County. 1979, Emerg; January 17, 1985, Reg..., Township of, Clarion 422365 February 11, ......do Do. County. 1976, Emerg; July 3, 1985, Reg; December 2...

Four Fish kills Spanning 2011 – 2013 in the Red River Watershed Beaver Creek to Lake Texoma, OK

EPA Science Inventory

The USEPA/ORD-National Exposure Research Laboratory-Environmental Sciences Division (USEPA/ORD-NERL-ESD) assisted USEPA Region 6 and the State of Oklahoma Department of Environmental Quality (OKDEQ) in identifying unknown contaminant(s) that were present during four fish kills in...

Flooding, Beavers, and Hardwood Seedling Survival

Treesearch

Roger M. Krinard; Robert L. Johnson

1981-01-01

Plantings were made for three successive years on clay-capped soils in the Mississippi River batture, the first year without flooding, and the second and third years with flooding. Species planted, but not in all years, were eastern cottonwood (Populus deltoides Bartr. ex Marsh.), sycamore (Platanus occidentalis L.), green ash (...

Notes on Antarctic Aviation

DTIC Science & Technology

1993-08-01

4 5. Curtiss-Wright T -32 biplane used by the second Byrd Antarctic Expedition...pack ice north of Mawson ............................................ 7 10. USN ski-wheel Douglas R4D-8 at McMurdo...McMurdo ................. 11 17. ANARE ski-wheel DHC-2 Beaver over Mawson ............................................ 12 18. USN ski-wheel DHC-3 Otter

Teacher Perceptions of Administrator Leadership Styles Regarding Job Satisfaction

ERIC Educational Resources Information Center

Johnson, Zachary Tyler

2017-01-01

One of the greatest challenges within education is a growing shortage of teachers (Epps & Foor, 2015). Various factors can be attributed to this phenomenon; however, two major factors that influence teachers to leave the profession are accountability and administrator leadership styles (Weinbaum, Weis, & Beaver, 2012). These two factors…

30. Photocopy from enlarged microfiche of 1896 drawing captioned: Part ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

30. Photocopy from enlarged microfiche of 1896 drawing captioned: Part of Plan C/80 showing changes proposed in end doors of Storehouse, then under construction by the Penn Bridge Co. of Beaver Falls, Pa. - Puget Sound Naval Shipyard, Pattern Shop, Farragut Avenue, Bremerton, Kitsap County, WA

main_title.html

Science.gov Websites

Poison Ivy Prairie Insects in Winter Red-tailed Hawk West Nile Virus Woodchuck Prairie Resources Deer and Beaver Bird Nests Buffalo Canada Geese Deer Fungi Grass Insects Lichens Math Patterns in Nature ;, Educational Images Ltd., Elmira, NY, used with permission. Red-tailed hawk: Original artwork: Louis Agassiz

Identification of differentially expressed placental transcripts during multiple gestations in the Eurasian beaver (Castor fiber L.).

PubMed

Lipka, A; Paukszto, L; Majewska, M; Jastrzebski, J P; Myszczynski, K; Panasiewicz, G; Szafranska, B

2017-09-01

The Eurasian beaver is one of the largest rodents that, despite its high impact on the environment, is a non-model species that lacks a reference genome. Characterising genes critical for pregnancy outcome can serve as a basis for identifying mechanisms underlying effective reproduction, which is required for the success of endangered species conservation programs. In the present study, high-throughput RNA sequencing (RNA-seq) was used to analyse global changes in the Castor fiber subplacenta transcriptome during multiple pregnancy. De novo reconstruction of the C. fiber subplacenta transcriptome was used to identify genes that were differentially expressed in placentas (n=5) from two females (in advanced twin and triple pregnancy). Analyses of the expression values revealed 124 contigs with significantly different expression; of these, 55 genes were identified using MegaBLAST. Within this group of differentially expressed genes (DEGs), 18 were upregulated and 37 were downregulated in twins. Most DEGs were associated with the following gene ontology terms: cellular process, single organism process, response to stimulus, metabolic process and biological regulation. Some genes were also assigned to the developmental process, the reproductive process or reproduction. Among this group, four genes (namely keratin 19 (Krt19) and wingless-type MMTV integration site family - member 2 (Wnt2), which were downregulated in twins, and Nik-related kinase (Nrk) and gap junction protein β2 (Gjb2), which were upregulated in twins) were assigned to placental development and nine (Krt19, Wnt2 and integrin α 7 (Itga7), downregulated in twins, and Nrk, gap junction protein β6 (Gjb6), GATA binding protein 6 (Gata6), apolipoprotein A-I (ApoA1), apolipoprotein B (ApoB) and haemoglobin subunit α 1 (HbA1), upregulated in twins) were assigned to embryo development. The results of the present study indicate that the number of fetuses affects the expression profile in the C. fiber subplacental transcriptome. Enhancement of transcriptomic resources for C. fiber will improve understanding of the pathways relevant to proper placental development and successful reproduction.

Spatial and seasonal variability of base flow in the Verde Valley, central Arizona, 2007 and 2011

USGS Publications Warehouse

Garner, Bradley D.; Bills, Donald J.

2012-01-01

Synoptic base-flow surveys were conducted on streams in the Verde Valley, central Arizona, in June 2007 and February 2011 by the U.S. Geological Survey (USGS), in cooperation with the Verde River Basin Partnership, the Town of Clarkdale, and Yavapai County. These surveys, also known as seepage runs, measured streamflow under base-flow conditions at many locations over a short period of time. Surveys were conducted on a segment of the Verde River that flows through the Verde Valley, between USGS streamflow-gaging stations 09504000 and 09506000, a distance of 51 river miles. Data from the surveys were used to investigate the dominant controls on Verde River base flow, spatial variability in gaining and losing reaches, and the effects that human alterations have on base flow in the surface-water system. The most prominent human alterations in the Verde Valley are dozens of surface-water diversions from streams, including gravity-fed ditch diversions along the Verde River.Base flow that entered the Verde River from the tributary streams of Oak Creek, Beaver Creek, and West Clear Creek was found to be a major source of base flow in the Verde River. Groundwater discharge directly into the Verde River near these three confluences also was an important contributor of base flow to the Verde River, particularly near the confluence with Beaver Creek. An examination of individual reaches of the Verde River in the Verde Valley found three reaches (largely unaffected by ditch diversions) exhibiting a similar pattern: a small net groundwater discharge in February 2011 (12 cubic feet per second or less) and a small net streamflow loss in June 2007 (11 cubic feet per second or less). Two reaches heavily affected by ditch diversions were difficult to interpret because of the large number of confounding human factors. Possible lower and upper bounds of net groundwater flux were calculated for all reaches, including those heavily affected by ditches.

78 FR 72911 - Changes in Flood Hazard Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-04

.... Midland Fields, MI 48640. 333 West Ellsworth Street, Midland, MI 48640. Oakland City of Troy (13- The....fema.gov/ City of Troy, Troy, MI 48084. lomc. 500 West Big Beaver Road, Troy, MI 48084. Missouri...:// January 30, 2014 290869 Areas of Lincoln Presiding Troy, MO 63379. www.msc.fema.gov/ County (13-07...

Use of H2Ri wicking fabric to prevent frost boils in the Dalton Highway Beaver Slide area, Alaska final report.

DOT National Transportation Integrated Search

2012-08-01

Many roads in Alaska, such as the Dalton Highway, experience degradation during spring thaw due to the downslope running of shallow groundwater. The water flow : down the slope and pools up in the road embankments, where it freezes, causing frost boi...

40 CFR 147.102 - Aquifer exemptions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... than the indicated depths below the ground surface, and described by a 1/4 mile area beyond and lying directly below the following oil and gas producing fields: (i) Swanson River Field—1700 feet. (ii) Beaver Creek Field—1650 feet. (iii) Kenai Gas Field—1300 feet. (2) The portion of aquifers beneath Cook Inlet...

40 CFR 147.102 - Aquifer exemptions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... than the indicated depths below the ground surface, and described by a 1/4 mile area beyond and lying directly below the following oil and gas producing fields: (i) Swanson River Field—1700 feet. (ii) Beaver Creek Field—1650 feet. (iii) Kenai Gas Field—1300 feet. (2) The portion of aquifers beneath Cook Inlet...

40 CFR 147.102 - Aquifer exemptions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... than the indicated depths below the ground surface, and described by a 1/4 mile area beyond and lying directly below the following oil and gas producing fields: (i) Swanson River Field—1700 feet. (ii) Beaver Creek Field—1650 feet. (iii) Kenai Gas Field—1300 feet. (2) The portion of aquifers beneath Cook Inlet...

40 CFR 147.102 - Aquifer exemptions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... than the indicated depths below the ground surface, and described by a 1/4 mile area beyond and lying directly below the following oil and gas producing fields: (i) Swanson River Field—1700 feet. (ii) Beaver Creek Field—1650 feet. (iii) Kenai Gas Field—1300 feet. (2) The portion of aquifers beneath Cook Inlet...

MOLECULAR CHARACTERIZATION OF MICROSPORIDIA INDICATES THAT FUR-BEARING WILD MAMMALS CAN BE A SOURCE OF HUMAN PATHOGENIC ENTEROCYTOZOON BIENEUSI

EPA Science Inventory

Over 13 months, 465 beavers, foxes, muskrats, otters, and raccoons were trapped in four counties in eastern Maryland and examined by molecular methods for microsporidia. A two-step nested PCR protocol was developed to amplify a 392 bp fragment of the internal transcribed spacer (...

Effective Crisis Management at the Smaller Campus.

ERIC Educational Resources Information Center

DeWitt, Robert C.

Pennsylvania State University Beaver Campus developed crisis guidelines and a formal working relationship with a local community mental health center in order to be able to deal with on-campus crises and their followup. The guidelines provide each employee with a single, easy-to-follow document that outlines the decision making process to be…

How Could a Beaver Start a War?

ERIC Educational Resources Information Center

Millward, Robert

2010-01-01

Students gain a better understanding of war and economics when the variables come alive through stories, artifacts, and paintings. In this article, the author describes a short story about the fur trade which can generate lots of student questions about the fur economics, the Eastern Woodland Indians, trade artifacts, and war. The author also…

Towing Tank Measurements of Hydrodynamic Performance of a Horizontal Axis Tidal Turbine Under Unsteady Flow Conditions

DTIC Science & Technology

2013-05-10

John Zseleczky, Mr. Daniel Rhodes, Mr. Bill Beaver and all staff of US Naval Academy Hydromechanics Laboratory for their contributions in designing...turbine centerline. Tip vortex influence was most prevalent at X/D = 0.19, the closest measured plane to the turbine plane pictured in Figure 31

75 FR 430 - Notice of Intent To Prepare an Environmental Impact Statement for the Sigurd-Red Butte...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-05

...; UTU-83067] Notice of Intent To Prepare an Environmental Impact Statement for the Sigurd-Red Butte...) Cedar City Field Office, Cedar City, Utah, intends to prepare an Environmental Impact Statement (EIS... Fishlake National Forests), State of Utah, Millard County, Sevier County, Beaver County, Utah Division of...

75 FR 19991 - Notice of Availability of the Final Environmental Impact Statement for the UNEV Refined Liquid...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-16

...-82385] Notice of Availability of the Final Environmental Impact Statement for the UNEV Refined Liquid...) has prepared a Proposed Resource Management Plan Amendment (RMPA)/Final Environmental Impact Statement..., Tooele, Juab, Millard, Beaver, Iron, and Washington Counties in Utah; and Lincoln and Clark Counties in...

Development of Thinking for Speaking: What Role Does Language Socialization Play?

ERIC Educational Resources Information Center

Wu, Shu-Ling

2016-01-01

It has been noted that Chinese shows both satellite- and verb-framed properties (Beavers, Levin, & Tham, 2010; Slobin, 2004), a fact that offers the opportunity to explore the typological influence of learners' dominant language because they can choose either option to describe the same motion events and be grammatically correct. This study…

77 FR 62147 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Pittsburgh-Beaver...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-12

... completeness requirement for one or more quarters during 2009-2011. EPA addressed the missing data of each of...-assured, quality-controlled and certified ambient air monitoring data for the 2008-2010 and 2009-2011...- assured, quality-controlled, and certified monitoring data for the 2007-2009 monitoring period, that the...

Age-of-Recall Effects on Family-of-Origin Ratings.

ERIC Educational Resources Information Center

Hampson, Robert B.; And Others

1994-01-01

College students (n=141) completed Self-Report Family Inventory on Beavers Systems Model of Family Functioning, rating current family, family when they were 10 years old, and family when they were 16 years old. Found significant differences between age-of-recall groups, with recall ratings from age 10 significantly more competent, cohesive, and…

A Dogrib History. Grade 1-3.

ERIC Educational Resources Information Center

Fraser, Tara

A publication on the history and traditional lifestyle of the Dogrib Tribe of Canada's Northwest Territories is intended for use in grades 1-3. Text is printed in large, clear letters and accompanied by many drawings. Some subjects covered are cooking, food, canoes, clothes, homes, and games. Sections are devoted to beavers and caribou and their…

The Tug of War between Phonological, Semantic and Shape Information in Language-Mediated Visual Search

ERIC Educational Resources Information Center

Huettig, Falk; McQueen, James M.

2007-01-01

Experiments 1 and 2 examined the time-course of retrieval of phonological, visual-shape and semantic knowledge as Dutch participants listened to sentences and looked at displays of four pictures. Given a sentence with "beker," "beaker," for example, the display contained phonological (a beaver, "bever"), shape (a…

More How Stories From Alaska.

ERIC Educational Resources Information Center

Gray, Minnie

Taken from Alaskan oral tradition, the five "how" stories are written in simple English prose. "The Four Qayaqs" explains why the porcupine has no fat on his stomach and the beaver has none on his back. "Ptarmigan and the Sandhill Crane" tells how the two very different birds come to look alike. In "Why the Dall…

77 FR 13010 - Suspension of Community Eligibility

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-05

.... Emerg; August 24, 1984, Reg; March 15, 2012, Susp. Beaver, Township of, 422441 May 15, 1979, ......do Do... of, 420508 May 18, 1976, ......do Do. Jefferson County. Emerg; June 4, 1990, Reg; March 15, 2012.... Emerg; April 16, 1991, Reg; March 15, 2012, Susp. Clover, Township of, 422442 May 18, 1976, ......do Do...

5 CFR 532.285 - Special wage schedules for supervisors of negotiated rate Bureau of Reclamation employees.

Code of Federal Regulations, 2012 CFR

2012-01-01

... industry titles 211 Oil and gas extraction. 212 Mining (except oil and gas). 213 Support activities for..., Bend, Medford, Umatilla, Multnomah Utah: Salt Lake Idaho: Ada, Canyon, Adams Washington: Spokane, Grant..., Platte, Niobrara, Converse, Natrona, Fremont, Sublette, Lincoln Utah: Beaver, Box Elder, Cache, Carbon...

5 CFR 532.285 - Special wage schedules for supervisors of negotiated rate Bureau of Reclamation employees.

Code of Federal Regulations, 2010 CFR

2010-01-01

... industry titles 211 Oil and gas extraction. 212 Mining (except oil and gas). 213 Support activities for..., Bend, Medford, Umatilla, Multnomah Utah: Salt Lake Idaho: Ada, Canyon, Adams Washington: Spokane, Grant..., Platte, Niobrara, Converse, Natrona, Fremont, Sublette, Lincoln Utah: Beaver, Box Elder, Cache, Carbon...

5 CFR 532.285 - Special wage schedules for supervisors of negotiated rate Bureau of Reclamation employees.

Code of Federal Regulations, 2011 CFR

2011-01-01

... industry titles 211 Oil and gas extraction. 212 Mining (except oil and gas). 213 Support activities for..., Bend, Medford, Umatilla, Multnomah Utah: Salt Lake Idaho: Ada, Canyon, Adams Washington: Spokane, Grant..., Platte, Niobrara, Converse, Natrona, Fremont, Sublette, Lincoln Utah: Beaver, Box Elder, Cache, Carbon...

5 CFR 532.285 - Special wage schedules for supervisors of negotiated rate Bureau of Reclamation employees.

Code of Federal Regulations, 2013 CFR

2013-01-01

... industry titles 211 Oil and gas extraction. 212 Mining (except oil and gas). 213 Support activities for..., Bend, Medford, Umatilla, Multnomah Utah: Salt Lake Idaho: Ada, Canyon, Adams Washington: Spokane, Grant..., Platte, Niobrara, Converse, Natrona, Fremont, Sublette, Lincoln Utah: Beaver, Box Elder, Cache, Carbon...

5 CFR 532.285 - Special wage schedules for supervisors of negotiated rate Bureau of Reclamation employees.

Code of Federal Regulations, 2014 CFR

2014-01-01

... industry titles 211 Oil and gas extraction. 212 Mining (except oil and gas). 213 Support activities for..., Bend, Medford, Umatilla, Multnomah Utah: Salt Lake Idaho: Ada, Canyon, Adams Washington: Spokane, Grant..., Platte, Niobrara, Converse, Natrona, Fremont, Sublette, Lincoln Utah: Beaver, Box Elder, Cache, Carbon...

Water quality trends in the Blackwater River watershed, West Virginia

USGS Publications Warehouse

Smith, Jessica; Welsh, Stuart A.; Anderson, James T.; Fortney, Ronald H.

2015-01-01

An understanding of historic and current water quality is needed to manage and improve aquatic communities within the Blackwater River watershed, WV. The Blackwater River, which historically offered an excellent Salvelinus fontinalis (Brook Trout) fishery, has been affected by logging, coal mining, use of off-road vehicles, and land development. Using information-theoretic methods, we examined trends in water quality at 12 sites in the watershed for the 14 years of 1980–1993. Except for Beaver Creek, downward trends in acidity and upward trends in alkalinity, conductivity, and hardness were consistent with decreases in hydrogen ion concentration. Water-quality trends for Beaver Creek were inconsistent with the other sites and reflect ongoing coal-mining influences. Dissolved oxygen trended downward, possibly due to natural conditions, but remained above thresholds that would be detrimental to aquatic life. Water quality changed only slightly within the watershed from 1980–1993, possibly reflecting few changes in development and land uses during this time. These data serve as a baseline for future water-quality studies and may help to inform management planning.

Human-induced changes in animal populations and distributions, and the subsequent effects on fluvial systems

NASA Astrophysics Data System (ADS)

Butler, David R.

2006-09-01

Humans have profoundly altered hydrological pathways and fluvial systems through their near-extirpation of native populations of animal species that strongly influenced hydrology and removal of surface sediment, and through the introduction of now-feral populations of animals that bring to bear a suite of different geomorphic effects on the fluvial system. In the category of effects of extirpation, examples are offered through an examination of the geomorphic effects and former spatial extent of beavers, bison, prairie dogs, and grizzly bears. Beavers entrapped hundreds of billions of cubic meters of sediment in North American stream systems prior to European contact. Individual bison wallows, that numbered in the range of 100 million wallows, each displaced up to 23 m 3 of sediment. Burrowing by prairie dogs displaced more than 5000 kg and possibly up to 67,500 kg of sediment per hectare. In the category of feral populations, the roles of feral rabbits, burros and horses, and pigs are highlighted. Much work remains to adequately quantify the geomorphic effects animals have on fluvial systems, but the influence is undeniable.

Regional potentiometric-surface map of the Great Basin carbonate and alluvial aquifer system in Snake Valley and surrounding areas, Juab, Millard, and Beaver Counties, Utah, and White Pine and Lincoln Counties, Nevada

USGS Publications Warehouse

Gardner, Philip M.; Masbruch, Melissa D.; Plume, Russell W.; Buto, Susan G.

2011-01-01

Water-level measurements from 190 wells were used to develop a potentiometric-surface map of the east-central portion of the regional Great Basin carbonate and alluvial aquifer system in and around Snake Valley, eastern Nevada and western Utah. The map area covers approximately 9,000 square miles in Juab, Millard, and Beaver Counties, Utah, and White Pine and Lincoln Counties, Nevada. Recent (2007-2010) drilling by the Utah Geological Survey and U.S. Geological Survey has provided new data for areas where water-level measurements were previously unavailable. New water-level data were used to refine mapping of the pathways of intrabasin and interbasin groundwater flow. At 20 of these locations, nested observation wells provide vertical hydraulic gradient data and information related to the degree of connection between basin-fill aquifers and consolidated-rock aquifers. Multiple-year water-level hydrographs are also presented for 32 wells to illustrate the aquifer system's response to interannual climate variations and well withdrawals.

Fluid flow in a porous medium with transverse permeability discontinuity

NASA Astrophysics Data System (ADS)

Pavlovskaya, Galina E.; Meersmann, Thomas; Jin, Chunyu; Rigby, Sean P.

2018-04-01

Magnetic resonance imaging (MRI) velocimetry methods are used to study fully developed axially symmetric fluid flow in a model porous medium of cylindrical symmetry with a transverse permeability discontinuity. Spatial mapping of fluid flow results in radial velocity profiles. High spatial resolution of these profiles allows estimating the slip in velocities at the boundary with a permeability discontinuity zone in a sample. The profiles are compared to theoretical velocity fields for a fully developed axially symmetric flow in a cylinder derived from the Beavers-Joseph [G. S. Beavers and D. D. Joseph, J. Fluid Mech. 30, 197 (1967), 10.1017/S0022112067001375] and Brinkman [H. C. Brinkman, Appl. Sci. Res. A 1, 27 (1947), 10.1007/BF02120313] models. Velocity fields are also computed using pore-scale lattice Boltzmann modeling (LBM) where the assumption about the boundary could be omitted. Both approaches give good agreement between theory and experiment, though LBM velocity fields follow the experiment more closely. This work shows great promise for MRI velocimetry methods in addressing the boundary behavior of fluids in opaque heterogeneous porous media.

A Process-Based Assessment for Watershed Restoration Planning, Chehalis River Basin, USA

NASA Astrophysics Data System (ADS)

Beechie, T. J.; Thompson, J.; Seixas, G.; Fogel, C.; Hall, J.; Chamberlin, J.; Kiffney, P.; Pollock, M. M.; Pess, G. R.

2016-12-01

Three key questions in identifying and prioritizing river restoration are: (1) How have habitats changed?, (2) What are the causes of those habitat changes?, and (3) How of those changes affected the species of interest? To answer these questions and assist aquatic habitat restoration planning in the Chehalis River basin, USA, we quantified habitat changes across the river network from headwaters to the estuary. We estimated historical habitat capacity to support salmonids using a combination of historical assessments, reference sites, and models. We also estimated current capacity from recent or newly created data sets. We found that losses of floodplain habitats and beaver ponds were substantial, while the estuary was less modified. Both tributary and main channel habitats—while modified—did not show particularly large habitat changes. Assessments of key processes that form and sustain habitats indicate that riparian functions (shading and wood recruitment) have been significantly altered, although peak and low flows have also been altered in some locations. The next step is to link our habitat assessments to salmon life-cycle models to evaluate which life stages and habitat types currently constrain population sizes of spring and fall Chinook salmon, coho salmon, and steelhead. By comparing model runs that represent different components of habitat losses identified in the analysis above, life-cycle models help identify which habitat losses have most impacted each species and population. This assessment will indicate which habitat types provide the greatest restoration potential, and help define a guiding vision for restoration efforts. Future analyses may include development and evaluation of alternative restoration scenarios, including different climate change scenarios, to refine our understanding of which restoration actions provide the greatest benefit to a salmon population.

Simulated effects of recruitment variability, exploitation, and reduced habitat area on the muskellunge population in Shoepack Lake, Voyageurs National Park, Minnesota

USGS Publications Warehouse

Frohnauer, N.K.; Pierce, C.L.; Kallemeyn, L.W.

2007-01-01

The genetically unique population of muskellunge Esox masquinongy inhabiting Shoepack Lake in Voyageurs National Park, Minnesota, is potentially at risk for loss of genetic variability and long-term viability. Shoepack Lake has been subject to dramatic surface area changes from the construction of an outlet dam by beavers Castor canadensis and its subsequent failure. We simulated the long-term dynamics of this population in response to recruitment variation, increased exploitation, and reduced habitat area. We then estimated the effective population size of the simulated population and evaluated potential threats to long-term viability, based on which we recommend management actions to help preserve the long-term viability of the population. Simulations based on the population size and habitat area at the beginning of a companion study resulted in an effective population size that was generally above the threshold level for risk of loss of genetic variability, except when fishing mortality was increased. Simulations based on the reduced habitat area after the beaver dam failure and our assumption of a proportional reduction in population size resulted in an effective population size that was generally below the threshold level for risk of loss of genetic variability. Our results identified two potential threats to the long-term viability of the Shoepack Lake muskellunge population, reduction in habitat area and exploitation. Increased exploitation can be prevented through traditional fishery management approaches such as the adoption of no-kill, barbless hook, and limited entry regulations. Maintenance of the greatest possible habitat area and prevention of future habitat area reductions will require maintenance of the outlet dam built by beavers. Our study should enhance the long-term viability of the Shoepack Lake muskellunge population and illustrates a useful approach for other unique populations. ?? Copyright by the American Fisheries Society 2007.

Rapid plant diversity assessment using a pixel nested plot design: A case study in Beaver Meadows, Rocky Mountain National Park, Colorado, USA

USGS Publications Warehouse

Kalkhan, M.A.; Stafford, E.J.; Stohlgren, T.J.

2007-01-01

Geospatial statistical modelling and thematic maps have recently emerged as effective tools for the management of natural areas at the landscape scale. Traditional methods for the collection of field data pertaining to questions of landscape were developed without consideration for the parameters of these applications. We introduce an alternative field sampling design based on smaller unbiased random plot and subplot locations called the pixel nested plot (PNP). We demonstrate the applicability of the PNP design of 15 m x 15 m to assess patterns of plant diversity and species richness across the landscape at Rocky Mountain National Park (RMNP), Colorado, USA in a time (cost)-efficient manner for field data collection. Our results produced comparable results to a previous study in the Beaver Meadow study (BMS) area within RMNP, where there was a demonstrated focus of plant diversity. Our study used the smaller PNP sampling design for field data collection which could be linked to geospatial information data and could be used for landscape-scale analyses and assessment applications. In 2003, we established 61 PNP in the eastern region of RMNP. We present a comparison between this approach using a sub-sample of 19 PNP from this data set and 20 of Modified Whittaker nested plots (MWNP) of 20 m x 50 m that were collected in the BMS area. The PNP captured 266 unique plant species while the MWNP captured 275 unique species. Based on a comparison of PNP and MWNP in the Beaver Meadows area, RMNP, the PNP required less time and area sampled to achieve a similar number of species sampled. Using the PNP approach for data collection can facilitate the ecological monitoring of these vulnerable areas at the landscape scale in a time- and therefore cost-effective manner. ?? 2007 The Authors.

Effect of whole catchment liming on the episodic acidification of two adirondack streams

USGS Publications Warehouse

Newton, R.M.; Burns, Douglas A.; Blette, V.L.; Driscoll, C.T.

1996-01-01

During the fall of 1989 7.7Mg/ha of calcium carbonate was applied on two tributary catchments (40 ha and 60 ha) to Woods Lake, a small (25 ha) acidic headwater lake in the western Adirondack region of New York. Stream-water chemistry in both catchment tributaries responded immediately. Acid-neutralizing capacity (ANC) increased by more than 200 ??eq/L in one of the streams and more than 1000 ??eq/L in the other, from pre-liming values which ranged from -25 to +40 ??eq/L. The increase in ANC was primarily due to increases in dissolved Ca2+ concentrations. Most of the initial response of the streams was due to the dissolution of calcite that fell directly into the stream channels and adjacent wetlands. A small beaver impoundment and associated wetlands were probably responsible for the greater response observed in one of the streams. After the liming of subcatchmentIV (60 ha), Ca2+ concentrations increased with increasing stream discharge in the stream during fall rain events, suggesting a contribution from calcite dissolved within the soil and transported to the stream by surface runoff or shallow interflow. Concentrations of other ions not associated with the calcite (e.g. Na+) decreased during fall rain events, presumably due to mixing of solute-rich base flow with more dilute shallow interflow. The strong relation between changes in Ca2+ and changes in NO3- concentrations during spring snowmelt, (r2 = 0.93, slope = 0.96, on an equivalent basis) suggests that both solutes had a common source in the organic horizon of the soil. Increases in NO3- concentrations during snowmelt were balanced by increases in Ca2+ that was released either directly from the calcite or from exchange sites, mitigating episodic acidification of the stream. However, high ambient NO3- concentrations and relatively low ambient Ca2+ concentrations in the stream during the spring caused the stream to become acidic despite the CaCO3 treatment. In stream WO2 (40ha), Ca2+ concentrations were much higher than in stream WO4 because of the dissolution of calcite which fell directly into the upstream beaver pond and its associated wetlands. Calcium concentrations decreased as both NO3- concentrations and stream discharge increased, due to the dilution of Ca-enriched beaver pond water by shallow interflow. Despite this dilution, Ca2+ concentrations were high enough to more than balance strong acid anion (SO42-, NO3-, Cl-) concentrations, resulting in a positive ANC in this stream throughout the year. These data indicate that liming of wetlands and beaver ponds is more effective than whole catchment liming in neutralizing acidic surface waters. ?? 1996 Kluwer Academic Publishers.

Predictors of breeding site occupancy by amphibians in montane landscapes

USGS Publications Warehouse

Groff, Luke A.; Loftin, Cynthia S.; Calhoun, Aram J.K.

2017-01-01

Ecological relationships and processes vary across species’ geographic distributions, life stages and spatial, and temporal scales. Montane landscapes are characterized by low wetland densities, rugged topographies, and cold climates. Consequently, aquatic-dependent and low-vagility ectothermic species (e.g., pool-breeding amphibians) may exhibit unique ecological associations in montane landscapes. We evaluated the relative importance of breeding- and landscape-scale features associated with spotted salamander (Ambystoma maculatum) and wood frog (Lithobates sylvaticus) wetland occupancy in Maine's Upper Montane-Alpine Zone ecoregion, and we determined whether models performed better when the inclusive landscape-scale covariates were estimated with topography-weighted or circular buffers. We surveyed 135 potential breeding sites during May 2013–June 2014 and evaluated environmental relationships with multi-season implicit dynamics occupancy models. Breeding site occupancy by both species was influenced solely by breeding-scale habitat features. Spotted salamander occupancy probabilities increased with previous or current beaver (Castor canadensis) presence, and models generally were better supported when the inclusive landscape-scale covariates were estimated with topography-weighted rather than circular buffers. Wood frog occupancy probabilities increased with site area and percent shallows, but neither buffer type was better supported than the other. Model rank order and support varied between buffer types, but model inferences did not. Our results suggest pool-breeding amphibian conservation in montane Maine include measures to maintain beaver populations and large wetlands with proportionally large areas of shallows ≤1-m deep. Inconsistencies between our study and previous studies substantiate the value of region-specific research for augmenting species’ conservation management plans and suggest the application of out-of-region inferences may promote ineffective conservation. 

Landscape consequences of natural gas extraction in Beaver and Butler Counties, Pennsylvania, 2004-2010

USGS Publications Warehouse

Roig-Silva, Coral M.; Slonecker, E. Terry; Milheim, Lesley E.; Malizia, Alexander R.

2013-01-01

Increased demands for cleaner burning energy, coupled with the relatively recent technological advances in accessing unconventional hydrocarbon-rich geologic formations, have led to an intense effort to find and extract natural gas from various underground sources around the country. One of these sources, the Marcellus Shale, located in the Allegheny Plateau, is currently undergoing extensive drilling and production. The technology used to extract gas in the Marcellus Shale is known as hydraulic fracturing and has garnered much attention because of its use of large amounts of fresh water, its use of proprietary fluids for the hydraulic-fracturing process, its potential to release contaminants into the environment, and its potential effect on water resources. Nonetheless, development of natural gas extraction wells in the Marcellus Shale is only part of the overall natural gas story in this area of Pennsylvania. Conventional natural gas wells, which sometimes use the same technique, are commonly located in the same general area as the Marcellus Shale and are frequently developed in clusters across the landscape. The combined effects of these two natural gas extraction methods create potentially serious patterns of disturbance on the landscape. This document quantifies the landscape changes and consequences of natural gas extraction for Beaver County and Butler County in Pennsylvania between 2004 and 2010. Patterns of landscape disturbance related to natural gas extraction activities were collected and digitized using National Agriculture Imagery Program (NAIP) imagery for 2004, 2005/2006, 2008, and 2010. The disturbance patterns were then used to measure changes in land cover and land use using the National Land Cover Database (NLCD) of 2001. A series of landscape metrics is also used to quantify these changes and is included in this publication.

Ducks Overboard!

ERIC Educational Resources Information Center

Weiland, Ingrid; Sheffield, Caroline

2013-01-01

The authors open this article with a description of an incident that happened in 1992, when 28,800 rubber bath toys (i.e., ducks, frogs, turtles, and beavers) fell off a cargo ship in the middle of the Pacific Ocean. In 2009, these rubber bath toys were still washing ashore on beaches all around the world. This science instruction can be used with…

40 CFR 52.2027 - Approval status of Pennsylvania's Generic NOX and VOC RACT Rules.

Code of Federal Regulations, 2014 CFR

2014-07-01

... through 129.95 (see § 52.2020 (c)(129)) as those regulations apply to the Pittsburgh-Beaver Valley area... Generic NOX and VOC RACT Rules. 52.2027 Section 52.2027 Protection of Environment ENVIRONMENTAL PROTECTION...) Pennsylvania § 52.2027 Approval status of Pennsylvania's Generic NOX and VOC RACT Rules. (a) Effective November...

40 CFR 52.2027 - Approval status of Pennsylvania's Generic NOX and VOC RACT Rules.

Code of Federal Regulations, 2011 CFR

2011-07-01

... through 129.95 (see § 52.2020 (c)(129)) as those regulations apply to the Pittsburgh-Beaver Valley area... Generic NOX and VOC RACT Rules. 52.2027 Section 52.2027 Protection of Environment ENVIRONMENTAL PROTECTION...) Pennsylvania § 52.2027 Approval status of Pennsylvania's Generic NOX and VOC RACT Rules. (a) Effective November...

Characterization of Underwater Sounds Produced by a Backhoe Dredge Excavating Rock and Gravel

DTIC Science & Technology

2012-12-01

bathymetry, hydrodynamic conditions, prevalence of non-dredging ambient sounds), this study fills important knowledge gaps that contribute to better... Beaver Mackenzie, peak spectral levels were 122 dB at 190 m with a peak frequency of 120 Hz. Received levels in the 20- to 1000-Hz band were 133 dB

77 FR 61020 - Notice of Availability of Final Environmental Impact Statement for the Sigurd to Red Butte No. 2...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-05

...; UTU-83067] Notice of Availability of Final Environmental Impact Statement for the Sigurd to Red Butte... (BLM) has prepared a Final Environmental Impact Statement (EIS) for the Sigurd to Red Butte No. 2--345...; Utah School and Institutional Trust Lands Administration; Millard, Sevier, Beaver, Iron, and Washington...

75 FR 38116 - Notice of Availability of Record of Decision for the Approved Pony Express Resource Management...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-01

... Plan Amendment; UNEV Refined Liquid Petroleum Products Pipeline Environmental Impact Statement AGENCY... Environmental Impact Statement (EIS) published on April 16, 2010, is the same as that selected in the ROD. The..., Tooele, Juab, Millard, Beaver, Iron, and Washington Counties in Utah, and in Lincoln and Clark Counties...

76 FR 30962 - Notice of Availability of Draft Environmental Impact Statement for the Sigurd to Red Butte No. 2...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-27

...; UTU-83067] Notice of Availability of Draft Environmental Impact Statement for the Sigurd to Red Butte..., as amended, the Bureau of Land Management (BLM) has prepared a Draft Environmental Impact Statement... Service; State of Utah; Millard, Sevier, Beaver, Iron, and Washington counties, Utah; and the cities of St...

Minimum Entropy Autofocus Correction of Residual Range Cell Migration

DTIC Science & Technology

2017-03-02

reduced the residual to effectively a slowly varying bias on the order of a wavelength ( ∼ 3 cm ) which has negligible impact on the image focus. Fig...Fitzgerrell, and J. Beaver , “Two- dimensional phase gradient autofocus,” Proc. SPIE, vol. 4123, pp. 162– 173, 2000. [6] D. H. Brandwood, “A complex gradient

Influence of wood on invertebrate communities in streams and rivers

Treesearch

Arthur Benke; J. Bruce Wallace

2010-01-01

Wood plays a major role in creating multiple invertebrate habitats in small streams and large rivers. In small streams, wood debris dams are instrumental in creating a step and pool profile of habitats, enhancing habitat heterogeneity, retaining organic matter, and changing current velocity. Beavers can convert sections of free-flowing streams into ponds and wetlands...

Ward Doesn't Live Here Anymore.

ERIC Educational Resources Information Center

Coleman, Marion Tolbert

In this paper, reproduced from a speech given before the Communications Network in Philanthropy, the author uses television as a metaphor to explain the role of the family in the United States, focusing on the "Leave It to Beaver" series. An oral picture is used to discuss the changing nature of the family and divorce. First the family life of the…

77 FR 34297 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Pittsburgh-Beaver...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-11

... requirement, monitoring sites ID 42-003-0093 (North Park) and ID 42- 003-0095 (Moon) have missing data for the... monitoring periods 2007-2009 and 2008-2010, EPA has addressed the missing data by applying a recently... based upon complete, quality-assured and certified ambient air monitoring data for the 2008-2010 period...

The Association between Cardiovascular Disease and Cochlear Function in Older Adults

ERIC Educational Resources Information Center

Torre, Peter, III; Cruickshanks, Karen J.; Klein, Barbara E.K.; Klein, Ronald; Nondahl, David M.

2005-01-01

The purpose of this research was to evaluate the relation between self-reported cardiovascular disease (CVD) and cochlear function in older adults. The Epidemiology of Hearing Loss Study (EHLS) is an ongoing population-based study of hearing loss and its risk factors in Beaver Dam, Wisconsin. As part of the EHLS questionnaire, participants were…

Management of birch for wildlife habitat

Treesearch

Samuel P. Shaw

1969-01-01

The list of wildlife species known to prefer paper birch and yellow birch as food ls a long one. To mention a few: beavers and porcupines chew on the bark and wood; sapsuckers feed on the sap; other songbirds—notably the redpoll, pine siskin, and chikadee—relish the seeds; ruffed grouse eat the catkins, buds, and seeds (in northern Maine and Canada...

77 FR 25736 - Notice of Intent To Repatriate Cultural Items: Northwest Museum of Arts & Culture, Spokane, WA...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-01

... unassociated funerary objects are 7 beaver tooth dice, 1 bone awl pendant, 27 dentalia beads, 4 copper pendants, 1 copper bracelet, 1 projectile point, 1 bone awl, 2 scrapers, and 1 hammerstone. In the Federal... pendant, 5 scrapers, 2 bone awls, 1 piece of matting, 1 flake, 2 dentalia necklace fragments, 1 small box...

76 FR 73667 - Notice of Inventory Completion: U.S. Department of Defense, Army Corps of Engineers, Walla Walla...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-29

.... No known individuals were identified. The three associated funerary objects are 1 bone whistle from... associated funerary objects are 4 adze blades, 1 awl, 2 beaver incisors, 2 bone needles, 1 bone point, 1 bone toggle, 1 incised bird bone, 3 pieces of incised bone, 3 pestles, 3 polished bone items, 3 polished...

The Impact of Hearing Loss on Quality of Life in Older Adults

ERIC Educational Resources Information Center

Dalton, Dayna S.; Cruickshanks, Karen J.; Klein, Barbara E. K.; Klein, Ronald; Wiley, Terry L.; Nondahl, David M.

2003-01-01

Purpose: The authors investigate the impact of hearing loss on quality of life in a large population of older adults. Design and Methods: Data are from the 5-year follow-up Epidemiology of Hearing Loss Study, a population-based longitudinal study of age-related hearing impairment conducted in Beaver Dam, WI. Participants (N = 2,688) were 53-97…

Negotiating Citizenship: A Young Child's Collaborative Meaning-Making Constructions of Beavers as a Symbol of Canada

ERIC Educational Resources Information Center

Gillen, Julia; Cameron, Catherine Ann

2017-01-01

The right to share the social heritage of a nation is an element of citizenship closely associated with education. Social heritage is understood as the negotiation of understandings within a dialectical understanding of social practice across multiple timescales. In this paper the meaning-making practices of one young child concerned with beavers…

Silvies Valley Ranch, OR: using artificial beaver dams to restore incised streams

Treesearch

Rachael Davee; Susan Charnley; Hannah Gosnell

2017-01-01

The Silvies Valley Ranch is an example of using local innovation to combat the global problem of incised streams on rangelands. Incised channels reduce the flow between water in the channel and water in the surrounding soils, which reduces the vegetation available for wildlife habitat and cattle forage. One of the ranch owners, Scott Campbell, a doctor of veterinary...

Money Matters: The American Experience with Money.

ERIC Educational Resources Information Center

Gittings, Tom; Goldsmith, Ken

From the earliest times when commodities such as tobacco and beaver pelts were used as money, to the present when credit and debit cards are commonplace, money has played a central role in the U.S. experience. This booklet provides an historical overview of the concept of money as it has evolved in the United States. The booklet is divided into…

50 CFR 32.55 - Oklahoma.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., A8, and A9 apply. 8. Hunters may place no more than one stand on the refuge. Stands may not be in... approved nontoxic shot while in the field (see § 32.2(k)). B. Upland Game Hunting. We allow hunting of... approved nontoxic shot while in the field (see § 32.2(k)). 5. You may hunt beaver during any established...

50 CFR 32.55 - Oklahoma.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., A8, and A9 apply. 8. Hunters may place no more than one stand on the refuge. Stands may not be in... approved nontoxic shot while in the field (see § 32.2(k)). B. Upland Game Hunting. We allow hunting of... approved nontoxic shot while in the field (see § 32.2(k)). 5. You may hunt beaver during any established...

50 CFR 32.55 - Oklahoma.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., A8, and A9 apply. 8. Hunters may place no more than one stand on the refuge. Stands may not be in... approved nontoxic shot while in the field (see § 32.2(k)). B. Upland Game Hunting. We allow hunting of... approved nontoxic shot while in the field (see § 32.2(k)). 5. You may hunt beaver during any established...

Lens opacities in women in Beaver Dam, Wisconsin: is there evidence of an effect of sex hormones?

PubMed Central

Klein, B E

1993-01-01

Analyses reported here suggest a protective effect of estrogen status on lens opacities, which are very common in adult Americans. Clinical trials are currently underway to assess protective effects of past menopausal estrogens on other disease. Evaluation of lenses of the participants would shed light on effects in the lens. PMID:8140704

77 FR 63811 - FFP Solia 6 Hydroelectric, LLC; Notice of Intent To File License Application, Filing of Pre...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-17

...: August 17, 2012. d. Submitted By: Free Flow Power Corporation on behalf of its subsidiary limited... River in Beaver County, Pennsylvania. The project would occupy United States lands administered by the U..., Boston, MA 02114-2130; (978) 283-2822; or email at flow-power.com ">[email protected] flow-power.com . i...

Spatial evaluation of precipitation in two large watersheds in north-central Arizona

Treesearch

Boris Poff; Assefa Desta; Aregai Tecle

2004-01-01

The USDA Forest Service established the Beaver Creek Experimental Watershed Pilot Project in north-central Arizona in 1957 and operated it until 1982. After the Forest Service discontinued the project in 1982, Northern Arizona University's School of Forestry continued to monitor and do research in two of the largest watersheds, known as Woods Canyon and Bar M....

Perfluorinated compounds in some terrestrial and aquatic wildlife species from Poland.

PubMed

Falandysz, J; Taniyasu, S; Yamashita, N; Rostkowski, P; Zalewski, K; Kannan, K

2007-05-01

Perfluorooctanesulfonate (PFOS) at 1.6-39 ng/g ww and 4.8-200 pg/mL, respectively, perfluorooctanoate (PFOA) at 0.06-0.28 ng/g ww and<0.05-1.8 pg/mL, and perfluorodecanoate (PFDA) at 0.13-0.57 ng/g ww and 0.05-1.8 pg/mL, were detected in all specimens of European Beaver's (Castor fiber) liver as well as in whole blood of Cod (Gadus morhua), Velvet Scoter (Melanitta fusca), Eider Duck (Sommateria mollisima), Long-tailed Duck (Clangula hyemalis), Razorbill (Alca torda), Red-throated Diver (Gavia stellata) sampled in Poland. At smaller concentrations and at less frequency was perfluorononanoate (PFNA) at 0.05-1.4 ng/g ww and<0.2-2 pg/mL, perfluorohexanoate (PFHxA) at 0.03-0.23 ng/g ww and<0.05-0.69 pg/mL, while perfluorohexanesulfonate (PFHxS) at 0.05-4.3 pg/mL and perfluorooctanesulfonamidoacetate (PFOSA) at 0.1-13 pg/mL were also found in Cod as well as in molluscivorous diving-ducks and fish-eating birds but not in Beaver, while perfluoroheptanoate (PFHpA) at<0.05-0.74 pg/mL was found only in Cod.

Tinnitus and its risk factors in the Beaver Dam offspring study.

PubMed

Nondahl, David M; Cruickshanks, Karen J; Huang, Guan-Hua; Klein, Barbara E K; Klein, Ron; Nieto, F Javier; Tweed, Ted S

2011-05-01

To assess the prevalence of tinnitus along with factors potentially associated with having tinnitus. Data were from the Beaver Dam Offspring Study, an epidemiological cohort study of aging. After a personal interview and audiometric examination, participants (n = 3267, ages 21-84 years) were classified as having tinnitus if in the past year they reported having tinnitus of at least moderate severity or that caused difficulty in falling asleep. The prevalence of tinnitus was 10.6%. In a multivariable logistic regression model adjusting for age and sex, the following factors were associated with having tinnitus: hearing impairment (Odds Ratio (OR) = 3.20), currently having a loud job (OR = 1.90), history of head injury (OR = 1.84), depressive symptoms (OR = 1.82), history of ear infection (men, OR = 1.75), history of target shooting (OR = 1.56), arthritis (OR = 1.46), and use of NSAID medications (OR = 1.33). For women, ever drinking alcohol in the past year was associated with a decreased risk of having tinnitus (OR = 0.56). These results suggest that tinnitus is a common symptom in this cohort and may be associated with some modifiable risk factors.

Hydrogeology and water quality of at the management systems evaluation area near Piketon, Ohio

USGS Publications Warehouse

Jagucki, M.L.; Finton, C.D.; Springer, A.E.; Bair, E.S.

1995-01-01

This report presents the results of a study by the U.S. Geological Survey, The Ohio State University, and the U.S. Department of Agriculture to describe the hydrology, water quality, and geochemical factors controlling water quality at the Ohio Management Systems Evaluation Area (MSEA). The Ohio MSEA is located on a 650-acre farm in the Scioto River Valley in Pike County, south-central Ohio. The farm is underlain by an incised bedrock valley filled with about 70 feet of sand and gravel outwash deposits that are covered by a veneer of silty clay alluvium and silty loam and sandy loam soils. Outwash sediment are composed predominantly of dolomite, quartz, and calcite, and have a median organic carbon concentration of 0.39 weight percent. Horizontal hydraulic conductivity of the sediment based on results of multiple-well aquifer tests ranges from 400 to 560 feet per day. Ground-water flow is from east to west-southwest at an average velocity of 1.5 to 2.5 feet per day. Ground water and surface water at the site are highly interconnected. Big Beaver Creek recharges the outwash aquifer along the eastern edge of the study area, and ground water discharges to the Scioto River at the western edge of the study area. High-stage events on the Scioto River cause frequent flow reversals in the aquifer that allow streamwater to travel a maximum observed distance of 190 feet inland. A zone of oxidizing waters (characterized by high dissolved oxygen concentration and Eh) is found in shallow ground water for several hundred feet adjacent to Big Beaver Creek and the Scioto River. This zone of oxidizing ground water is caused by the periodic inflow of surface waters to the aquifer. A ground-water budget for the study area indicates that the aquifer received 17.7 inches of recharge during water year 1992; of this amount, 72 percent originated as infiltrating precipitation, 28 percent as infiltration of surface water from Big Beaver Creek, and 0.2 percent as leakage from bedrock. Areal variation in water quality is caused by areal differences in the relative importance of these three recharge sources. The effects of bedrock leakage are evident only in the northeast corner of the study area. Here, deep outwash waters are transitional in composition between the calcium magnesium bicarbonate waters found elsewhere in the outwash aquifer and the calcium sodium chloride waters of the bedrock aquifer. Mixing calculations indicate that these deep outwash waters are composed of as much as 26 percent bedrock water. In the southern part of the MSEA, ground water is diluted by surface water from Big Beaver Creek as it recharges the aquifer through a sand and gravel streambed. At the northeast corner of the MSEA, however, Big Beaver Creek flows across a shale streambed through which no infiltration occurs. Redox reactions in the outwash aquifer control variations in aquifer chemistry with depth. From the water table to about 40 feet below land surface, oxidizing conditions are characterized by the presence of dissolved oxygen and nitrates in ground water, Eh greater than 200 millivolts, ferrihydrite coatings on sediment grains, and the absence of dissolved iron and manganese. From about 40 feet below land surface to the base of the aquifer, reducing conditions are characterized by dissolved oxygen concentrations less than 2 mg/L, Eh less than 200 millivolts, and the presence of dissolved iron and manganese. Denitrification in the reducing zone naturally remediates anthropogenic nitrate contamination of the aquifer while oxidizing pyrite in the aquifer sediment. ? The Ohio State University, Department of Geological Sciences, Columbus, Ohio.

Water Flow in the High Plains Aquifer in Northwestern Oklahoma

USGS Publications Warehouse

Luckey, Richard R.; Osborn, Noel I.; Becker, Mark F.; Andrews, William J.

2000-01-01

The High Plains is a major agricultural area, supported primarily by water from the High Plains aquifer, which is used to irrigate wheat and corn and to raise cattle and swine. The U.S. Geological Survey (USGS) and the Oklahoma Water Resources Board (OWRB) began a study of the High Plains aquifer in 1996. One purpose of the study was to develop a ground-water flow model that the OWRB could use to allocate the amount of water withdrawn from the a aquifer. The study area in Oklahoma covers all or parts of Beaver, Cimarron, Dewey, Ellis, Harper, Texas, and Woodward Counties. To provide appropriate hydrologic boundaries for the ground-water flow model, the study area was expanded to include parts of Colorado, Kansas, New Mexico, and Texas.

HEMISPHERIC CENTER FOR ENVIRONMENTAL TECHNOLOGY

DOE Office of Scientific and Technical Information (OSTI.GOV)

M.A. Ebadian

1999-09-30

The Princeton Plasma Physics Laboratory (PPPL) demonstration of the diamond wire cutting technology on the surrogate of the Tokamak Fusion Test Reactor (TFTR), Figure 1, was performed from August 23-September 3, 1999. The plated diamond wire, Figure 2, was successful in cutting through all components of the TFTR surrogate including stainless steel, inconel and graphite. The demonstration tested three different void fill materials (mortar with sand, Rheocell-15, and foam) and three cooling systems (water, air, and liquid nitrogen). The optimum combination was determined to be the use of the low-density concrete void fill, Rheocell-15 with an average density of 52more » lbs/ft{sup 3}, using a water coolant. However, the liquid nitrogen performed better than expected with only minor problems and was considered to be a successful demonstration of the Bluegrass Concrete Cutting, Inc. proprietary liquid-nitrogen coolant system. Data from the demonstration is being calculated and a summary of the technology demonstration will be included in the October monthly report. An ITSR will be written comparing the diamond wire saw to the plasma arc (baseline) technology. The MTR Chemical Protective Suit, a proprietary new suit from Kimberly Clark, was evaluated from 8/9/99 to 8/12/99 at Beaver, WV. This particular suit was tested on subjects performing three different tasks: climbing through a horizontal confined space, vertical confined space (pit), and loading and unloading material using a wheel barrow. Multiple test subjects performed each task for 20 minutes each. Performance of the innovative suit was compared to two commonly used types of protective clothing. Vital statistics, including body temperature and heart rate, were continuously monitored and recorded by an authorized physician. A summary of the demonstration will be included in the October monthly report. Along with the MTR Chemical Protective Suit, the VitalSense{trademark} Telemetric Monitoring System from Mini Mitter Co., Inc. was evaluated. A summary of the demonstration will be included in the October monthly report. A Kool-Vest from MicroClimate Systems, Inc. was evaluated during assessment at Beaver, WV from 8/16/99 to 8/17/99. The evaluation was performed in the same manner as the MTR Chemical Protective Suit described above. A summary of the demonstration will be included in the October monthly report. A brochure announcing the new Gateway to Environmental Technology (GET) website was produced by FIU-HCET and is being distributed to the D&D community by FETC-DDFA. The website provides links to the TIS and other decision support systems developed at FIU-HCET.« less

76 FR 73660 - Notice of Intent To Repatriate Cultural Items: U.S. Department of Defense, Army Corps of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-29

... bone whistle, 1 bone necklace, 2 bone combs, 1 horse tooth pendant, 1 bone gaming piece, 1 projectile..., 1 awl, 2 bear teeth, 20 beaver incisors, 6 bifaces, 3 bird bone whistles, 1 bone pendant, 1 carved antler item, 1 carved bone item, 5 copper pendants, 6 digging stick handles, 5 elk tooth beads, 1 incised...

12. INTERIOR VIEW, FIRST FLOOR SHOWING GRINDING STONES COVERED WITH ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. INTERIOR VIEW, FIRST FLOOR SHOWING GRINDING STONES COVERED WITH VATS (RIGHT STONE RUN BY 35' LEFFAL VERTICAL TURBINE; LEFT BY 23' 1EFFAL VERTICAL TURBINE). THE HOPPER ON THE VAT TO THE LEFT FUNNELS THE GRAIN IN. THE CHUTE AT THE BOTTOM OF THE CENTER VAT SENDS GROUND GRAIN TO THE CONVEYOR BELOW. - Schech's Mill, Beaver Creek State Park, La Crescent, Houston County, MN

BOREAS TGB-4 NSA-BVP Tower Flux and Meteorological Data

NASA Technical Reports Server (NTRS)

Roulet, Nigel T.; Hall, Forrest G. (Editor); Huemmrich, Karl (Editor); Conrad, Sara K. (Editor)

2000-01-01

The BOReal Ecosystem-Atmosphere Study Trace Gas Biogeochemistry (BOREAS TGB-4) team measured the exchange of heat, water, and CO2 between a boreal forest beaver pond and the atmosphere in the Northern Study Area (NSA) for the ice-free period of BOREAS. The data cover the period of 28-May to 18-Sep-1994. The data are available in tabular ASCII files.

Grindstone Flat and Big Flat enclosures - 41-year record of changes in clearcut aspen communities

Treesearch

Walter F. Mueggler; Dale L. Bartos

1977-01-01

The role of deer and cattle in the failure of aspen stands to regenerate on Beaver Mountain in southern Utah was investigated by a series of exclosures constructed in 1934. Three-fourths of each exclosure was clearcut of aspen in 1934. Aspen reproduction, shrubs, and herbaceous understory were measured in 1937, 1942, 1949, and 1975. Implications of wildlife and...

The Trinity River Greenway: A Prototype

DTIC Science & Technology

1972-06-01

study have gone into the formulation of a multipurpose plan of management designed to tame the raging waters of the Trinity, subdue its flooding crests...TABLE 6 MAMMALS OF THE STUDY AREA Shorttail Shrew (Blarina brevicauda) Beaver (Castor canadensis) Least Shrew (Crytotis parva) Armadillo (Dasypjs...property resulted. The Trinity became an J :enemy, a raging torrent to be tamed and eventually subdued. Meanwhile, thoughful men began to realize that

Novel Interventions for Heat/Exercise Induced Sudden Death and Fatigue

DTIC Science & Technology

2011-10-01

292(1): p. E331-E339. 26. Wasserman, K., Beaver, W.L. and Whipp, B.J. , Gas exchange theory and the lactic acidosis ( anaerobic ) threshold ...the anaerobic threshold . J Sports Sci Med, 2005. 4: p. 29-36. 28. McBride, A., Ghilagaber, S., Nikolaev, A., and Hardie, D.G., The glycogen- binding...Induced Sudden Death and Fatigue PRINCIPAL INVESTIGATOR: Susan L. Hamilton, Ph.D

78 FR 13384 - In the Matter of FirstEnergy Nuclear Operating Co. (Beaver Valley Units 1 and 2); Confirmatory...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-27

... under 10 CFR 2.315(c), must be filed in accordance with NRC E-Filing rule (72 FR 49139; August 28, 2007). The E-Filing process requires participants to submit and serve all adjudicatory documents over the.... To comply with the procedural requirements of E-Filing, at least 10 days prior to the filing deadline...

Copper Root Pruning and Container Cavity Size Influence Longleaf Pine Growth through Five Growing Seasons

Treesearch

James D. Haywood; Shi-Jean Susana Sung; Mary Anne Sword Sayer

2012-01-01

However, type and size of container can influence field performance. In this study, longleaf pine seedlings were grown in Beaver Plastics Styroblocks either without a copper treatment (Superblock) or with a copper oxychloride coating (Copperblock) and with three sizes of cavities that were 60, 108, and 164 ml. Seedlings from the six container types (two types of...

77 FR 47618 - Algonquin Power Company; Notice of Application Accepted for Amendment of License and Soliciting...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-09

... more information on how to submit these types of filings, please go to the Commission's Web site.... The project Lower Beaver Falls project works consist of: (1) A 4-acre reservoir formed by a 400-foot long concrete gravity dam with a maximum height of 14 feet, and a head pond elevation of 769.3 feet...

Investigating the anisotropy of magnetic susceptibility and other rock magnetic properties of the Beaver River Diabase in northeastern Minnesota

NASA Astrophysics Data System (ADS)

Hariri, Samer H.

The Beaver River Diabase (BRD) is a series of mafic dikes and sills within the Beaver Bay Complex (BBC) of northern Minnesota, which formed during the development of the ~1.1 Ga Midcontinent Rift (MCR). The BRD is one of the youngest and most extensive intrusive phases of the BBC. The BRD dikes and sills were emplaced into the medial levels of the 6-10 kilometer-thick North Shore Volcanic Group and occur over an arcuate area extending 120 by 20 kilometers. The BRD is composed of fine- to medium-grained ophitic olivine gabbro and does not display obvious foliation or lineation features and rarely displays modal layering. Without obvious magmatic internal structures, it is difficult to determine emplacement properties such as flow direction using standard geologic mapping or petrographic techniques. For this reason, we measured the anisotropy of magnetic susceptibility (AMS), in conjunction with other rock magnetic properties, to better understand the BRD's emplacement and deformation history in the context of the MCR. AMS measures the directional dependence of low-field magnetic susceptibility, and is used to infer a shape-preferred orientation of magnetic minerals within a rock, which can be related to specific emplacement mechanisms (e.g. directional flow or settling). Preliminary analysis of AMS at 20 sites within the southern half of the BRD (with 4-7 samples per site) shows maximum susceptibility values between 4.48 x 10-6 and 2.22 x 10-4 m 3/kg (1165 and 65400 μSI). Most specimens display nearly isotropic AMS ellipsoids (Pj < 1.15) with minor degrees of prolateness and oblateness. However, about 20% of specimens have higher anisotropies (Pj between 1.15 and 1.67) and higher degrees of oblateness and prolateness. Variations in AMS properties may reflect differences in concentration and composition of magnetic minerals, as well as emplacement mechanisms. Measurements of susceptibility as a function of temperature yield Curie points between 470 and 570 °C, indicating the presence of low-titanium titanomagnetite. Major hysteresis loops show coercivities between 1 and 25 mT, consistent with titanomagnetite as the dominant remanence carrier.

[Succession caused by beaver (Castor fiber L.) life activity: II. A refined Markov model].

PubMed

Logofet; Evstigneev, O I; Aleinikov, A A; Morozova, A O

2015-01-01

The refined Markov model of cyclic zoogenic successions caused by beaver (Castor fiber L.) life activity represents a discrete chain of the following six states: flooded forest, swamped forest, pond, grassy swamp, shrubby swamp, and wet forest, which correspond to certain stages of succession. Those stages are defined, and a conceptual scheme of probable transitions between them for one time step is constructed from the knowledge of beaver behaviour in small river floodplains of "Bryanskii Les" Reserve. We calibrated the corresponding matrix of transition probabilities according to the optimization principle: minimizing differences between the model outcome and reality; the model generates a distribution of relative areas corresponding to the stages of succession, that has to be compared to those gained from case studies in the Reserve during 2002-2006. The time step is chosen to equal 2 years, and the first-step data in the sum of differences are given various weights, w (between 0 and 1). The value of w = 0.2 is selected due to its optimality and for some additional reasons. By the formulae of finite homogeneous Markov chain theory, we obtained the main results of the calibrated model, namely, a steady-state distribution of stage areas, indexes of cyclicity, and the mean durations (M(j)) of succession stages. The results of calibration give an objective quantitative nature to the expert knowledge of the course of succession and get a proper interpretation. The 2010 data, which are not involved in the calibration procedure, enabled assessing the quality of prediction by the homogeneous model in short-term (from the 2006 situation): the error of model area distribution relative to the distribution observed in 2010 falls into the range of 9-17%, the best prognosis being given by the least optimal matrices (rejected values of w). This indicates a formally heterogeneous nature of succession processes in time. Thus, the refined version of the homogeneous Markov chain has not eliminated all the contradictions between the model results and expert knowledge, which suggests a further model development towards a "logically inhomogeneous" version or/and refusal to postulate the Markov property in the conceptual scheme of succession.

Nutrient, sediment, and pesticide data collected at four small agricultural basins in the Beaver Creek watershed, West Tennessee, 1990-1995

USGS Publications Warehouse

Williams, Shannon D.; Harris, Robin M.

1996-01-01

In 1989, the U.S. Geological Survey began a cooperative study with the Tennessee Department of Agriculture to assess the impact of agricultural activities on water quality in the Beaver Creek watershed in West Tennessee. Quantification of the transport of nutrients, sediment, and pesticides from agricultural fields was one of the objectives of the study. This report presents nutrient, sediment, and pesticide data collected during selected storm events from 1990 through 1995 at four relatively small, agricultural basins (28 to 422 acres) in the Beaver Creek watershed. Approximately 3,000 water samples (500 to 1,000 at each site) were analyzed for nitrogen and phosphorus species. Total nitrogen (N) concentrations ranged from 0.2 to 41.2 milligrams per liter (mg/L). Median concentrations for samples from each site ranged from 2.0 to 2.7 mg/L for total nitrogen, 1.2 to 1.9 mg/L for organic nitrogen, 0.05 to 0.14 mg/L for ammonia (measured as N), and 0.2 to 0.8 mg/L for nitrate plus nitrite (measured as N). Total phosphorus (P) concentrations ranged from 0.03 to 16.0 mg/L. Median concentrations for samples from each site ranged from 0.80 to 1.2 mg/L for total phosphorus and 0.15 to 0.72 for orthophosphate (measured as P). Approximately 6,000 water samples (1,300 to 1,800 at each site) were analyzed for suspended sediment. Suspended-sediment concentrations ranged from 8.0 to 98,353 mg/L. Concentrations exceeded 1,000 mg/L in 33 percent of the samples collected and exceeded 10,000 mg/L in 6 percent of the samples. Median concentrations ranged from 347 to 713 mg/L at the four sites. Several herbicides and insecticides were detected in water samples. Maximum concentrations detected were 37 micrograms per liter for metolachlor, 3.2 for trifluralin, 150 for fluometuron, and 430 for aldicarb. Aldicarb metabolites were also detected in several samples. The maximum aldicarb sulfoxide and aldicarb sulfone concentrations detected were 68.4 and 14.3 micrograms per liter, respectively.

Tree-Roost Characteristics of Subadult and Female Adult Bats (Nyctieius humeralis) in the Upper Coastal Plain of South Carolina.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Menzel, M.A.; Carter, T.C.; Ford, W.M.

Tree-roost of evening bats were identified by radio tracking of 14 individuals at the SRS. Bats roosted in longleaf pine cavities under exfoliating bark in snags near beaver ponds. The roosting occurred in open park like stands. No evening bats roosted in the more dense bottomland hardwood stands or mixed pine hardwood stands. None were observed in loblolly stands.

Agile Methods in Air Force Sustainment: Status and Outlook

DTIC Science & Technology

2014-07-01

Schwaber ISBN10: 073561993X X X Agile Project Management : Creating Innovative Products – 2nd Edition Jim Highsmith ISBN 0321658396 X Agile...ISBN 0787974277 X Leading Change John Kotter ISBN 0875847471 X Leading Geeks: How to Manage and Lead the People Who Deliver Technology Paul ...Development: Achieving Enterprise Agility Alan Shalloway, Guy Beaver, and James R. Trott ISBN 0321532899 X Managing Transitions: Making the Most of

A Species Distribution Modeling Informed Conservation Assessment of Bog Spicebush

DTIC Science & Technology

2016-09-14

small populations, or establishing new popu- lations to increase the metapopulation structure within clusters of popula- tions. These outplanting data...fire suppression, and flooding (e.g., due to beaver activity) on vege- tation composition and structure . This effort used vegetation and disturb- ance...Suppression to Prescription. Tall Timbers Research Station, Tallahassee, FL, pp 70–81. Godefroid, S., C. Piazza, G. Rossi, S. Buord, A. D. Stevens, R

"The Teenage Terror in the Schools": Adult Fantasies, American Youth, and Classroom Scare Films during the Cold War

ERIC Educational Resources Information Center

Garrison, Joshua

2009-01-01

Unrealistic as they may have been, television shows like Leave it to Beaver and Ozzie and Harriet served important social purposes during an age of tumult and anxiety. The domestic sit-coms of the 1950s played an educative function by reinforcing and disseminating traditional values at a time when forces of change were becoming quite disruptive.…

Biotic Drivers of Spatial Heterogeneity and Implications for River Ecosystems

NASA Astrophysics Data System (ADS)

Wohl, Ellen

2017-04-01

Rivers throughout the northern hemisphere have been simplified and homogenized by the removal of beavers and instream wood, along with numerous forms of channel engineering and flow regulation. Loss of spatial heterogeneity in river corridors - channels and floodplains - affects downstream fluxes of water, sediment, organic matter, and nutrients, as well as stream metabolism, biomass, and biodiversity. Recent work in streams of the Colorado Rocky Mountains illustrates how the presence of beavers and instream wood can facilitate spatial heterogeneity by creating stable, persistent, multithread channel planform and high channel-floodplain and channel-hyporheic zone connectivity. This spatial heterogeneity facilitates retention of water in pools, floodplain wetlands, and hyporheic storage. Suspended sediment, particulate organic matter (POM), and solutes are also more likely to be retained in these stream segments than in more uniform stream segments with greater downstream conveyance. Retention of POM and solutes equates to greater volumes of organic carbon storage per unit valley length and greater rates of nitrogen uptake. Spatially heterogeneous stream segments also exhibit greater biomass and biodiversity of aquatic macroinvertebrates, salmonid fish, and riparian spiders than do more uniform stream segments. These significant differences in stream form and function are unlikely to be unique to this field area and can provide a conceptual model for understanding and restoring ecosystem functions in other rivers.

Linking invasive exotic vertebrates and their ecosystem impacts in Tierra del Fuego to test theory and determine action

NASA Astrophysics Data System (ADS)

Valenzuela, Alejandro E. J.; Anderson, Christopher B.; Fasola, Laura; Cabello, José L.

2014-01-01

Understanding processes and impacts of biological invasions is fundamental for ecology and management. Recent reviews summarized the mechanisms by which invasive species alter entire ecosystems, but quantitative assessments of these mechanisms are lacking for actual assemblages to determine their relative importance, frequency and patterns. We updated information on introduced vertebrates in the Tierra del Fuego Archipelago (TDF) via an exhaustive literature review and new data to evaluate ecosystem impact mechanisms and provide management recommendations. To date, 24 exotic vertebrates have naturalized in TDF, outnumbering natives nearly 2:1, with the North American beaver (Castor canadensis) and muskrat (Ondatra zibethica) being the most widely distributed species and also impacting the ecosystem through the greatest number of mechanisms. Introduced vertebrates occupied most parts of the archipelago with human-inhabited islands having greater taxa richness. All exotics potentially altered ecosystems by one or more mechanisms: 100% food webs, 92% invasional meltdown, 42% habitat modification, 38% disease or parasite transmission, 21% soil property and disturbance regime changes. Impact to habitat structure was the main clustering criterion for this assemblage. Within the species that physically alter habitats, we found two sub-groups: 1) large herbivores and 2) "others" including beavers and muskrats. Species that did not alter habitat were divided further into those with predatory trophic effects (carnivorous mammals and trout, sub-group 4) and the rest with assorted impacts (sub-group 3). By establishing high quality information on archipelago-wide assemblage, distribution, impacts and mechanisms for exotic vertebrates, we recommend, based on ecological criteria, prioritizing the management of sub-group 2. A secondary priority might be given to the carnivores in sub-group 4, while species in sub-groups 1 and 3 are less urgent. As the first systematic survey of introduced fauna on an archipelago-scale, we identified knowledge gaps, such as population abundance and dynamics for specific species, which are needed to orient future work, but the notable progress made to date is highlighted.

Dry eye in the beaver dam offspring study: prevalence, risk factors, and health-related quality of life.

PubMed

Paulsen, Adam J; Cruickshanks, Karen J; Fischer, Mary E; Huang, Guan-Hua; Klein, Barbara E K; Klein, Ronald; Dalton, Dayna S

2014-04-01

To estimate dry eye prevalence in the Beaver Dam Offspring Study (BOSS), including a young adult population, and investigate associated risk factors and impact on health-related quality of life. Cohort study. The BOSS (2005-2008) is a study of aging in the adult offspring of the population-based Epidemiology of Hearing Loss Study cohort. Questionnaire data on health history, medication use, risk factors, and quality of life were available for 3275 participants. Dry eye was determined by self-report of frequency of symptoms and the intensity of those symptoms. Associations between dry eye and risk factors were analyzed using logistic regression. The prevalence of dry eye in the BOSS was 14.5%: 17.9% of women and 10.5% of men. In a multivariate model, statistically significant associations were found with female sex (odds ratio [OR], 1.68; 95% confidence interval [CI], 1.33-2.11), current contact lens use (OR, 2.01; 95% CI, 1.53-2.64), allergies (OR, 1.59; 95% CI, 1.22-2.08), arthritis (OR, 1.44; 95% CI, 1.12-1.85), thyroid disease (OR, 1.43; 95% CI, 1.02-1.99), antihistamine use (OR, 1.54; 95% CI, 1.18-2.02), and steroid use (OR, 1.54; 95% CI, 1.16-2.06). Dry eye was also associated with lower scores on the Medical Outcomes Study Short Form 36 (β = -3.9, P < .0001) as well as on the National Eye Institute 25-Item Visual Function Questionnaire (NEI VFQ-25) (β = -3.4, P < .0001) when controlling for age, sex, and comorbid conditions. The prevalence of dry eye and its associated risk factors in the BOSS were similar to previous studies. In this study, dry eye was associated with lower quality of life on a health-related quality-of-life instrument and the vision-specific NEI VFQ-25. Copyright © 2014 Elsevier Inc. All rights reserved.

The Snowmastodon Project: A view of the Last Interglacial Period from high in the Colorado Rockies

USGS Publications Warehouse

Pigati, Jeffery S.

2015-01-01

In North America, terrestrial records of biodiversity and climate change that span the Last Interglacial Period [or Marine Oxygen Isotope Stage (MIS) 5] are rare. In 2010-11, construction at Ziegler Reservoir near Snowmass Village, Colorado revealed a lacustrine/wetland sedimentary sequence that preserved evidence of past plant communities between ~140 and 55 ka, including all of MIS 5. At an elevation of 2705 m, the Ziegler Reservoir fossil site (ZRFS) also contained thousands of well-preserved bones and teeth of Pleistocene megafauna, including mastodons, mammoths, ground sloths, horses, camels, deer, bison, black bear, coyotes, and bighorn sheep. In addition, the site contained more than 26,000 bones from at least 30 species of small animals, including salamanders, otters, muskrats, minks, rabbits, beavers, frogs, lizards, snakes, fish, and birds. The combination of macro- and micro-vertebrates, invertebrates, terrestrial and aquatic plant macrofossils, a detailed pollen record, and a robust, directly dated stratigraphic framework, shows that high-elevation ecosystems in the Rocky Mountains of Colorado are climatically sensitive and varied dramatically throughout MIS 5.

A value-based medicine cost-utility analysis of idiopathic epiretinal membrane surgery.

PubMed

Gupta, Omesh P; Brown, Gary C; Brown, Melissa M

2008-05-01

To perform a reference case, cost-utility analysis of epiretinal membrane (ERM) surgery using current literature on outcomes and complications. Computer-based, value-based medicine analysis. Decision analyses were performed under two scenarios: ERM surgery in better-seeing eye and ERM surgery in worse-seeing eye. The models applied long-term published data primarily from the Blue Mountains Eye Study and the Beaver Dam Eye Study. Visual acuity and major complications were derived from 25-gauge pars plana vitrectomy studies. Patient-based, time trade-off utility values, Markov modeling, sensitivity analysis, and net present value adjustments were used in the design and calculation of results. Main outcome measures included the number of discounted quality-adjusted-life-years (QALYs) gained and dollars spent per QALY gained. ERM surgery in the better-seeing eye compared with observation resulted in a mean gain of 0.755 discounted QALYs (3% annual rate) per patient treated. This model resulted in $4,680 per QALY for this procedure. When sensitivity analysis was performed, utility values varied from $6,245 to $3,746/QALY gained, medical costs varied from $3,510 to $5,850/QALY gained, and ERM recurrence rate increased to $5,524/QALY. ERM surgery in the worse-seeing eye compared with observation resulted in a mean gain of 0.27 discounted QALYs per patient treated. The $/QALY was $16,146 with a range of $20,183 to $12,110 based on sensitivity analyses. Utility values ranged from $21,520 to $12,916/QALY and ERM recurrence rate increased to $16,846/QALY based on sensitivity analysis. ERM surgery is a very cost-effective procedure when compared with other interventions across medical subspecialties.

Yellowstone and the biology of time: Photographs across a century

USGS Publications Warehouse

Meagher, Mary; Houston, Douglas B.

1999-01-01

Established in 1872, Yellowstone National Park is the oldest and one of the largest national parks in the world. In this remarkable book, scientists Mary Meagher and Douglas B. Houston present 100 sets of photographs that compare the Yellowstone of old with the park of today.Most of the photo sets include three pictures-not the usual two-with many of the original views dating back to the 1870s and 1880s. From the same photo points used by early photographers, Meagher and Houston rephotographed the scenes in the 1970s, and then, following the great fires of 1988, again in the 1990s. The result is an illuminating record of Yellowstone’s dynamic ecosystem and its changes over time.Through close analysis of the photos and reference to the vast amount of available data, Meagher and Houston describe changes in vegetation, growth of wildlife populations, the effect of beaver occupancy on wetland areas, and geothermal and elevational shifts. At the same time they point out the extent to which many sites have not changed-despite important switches in park policy and an increase in human activity.Yellowstone National Park has long been the focus of major ecological debates. Should managers allow wildfires to burn? Should the elk and bison populations be controlled? Are too many people visiting the park? Yellowstone And The Biology Of Time offers a wealth of information to help us answer these questions. A visual treasure, this book will be of value to scientists from various disciplines as well as to the many people who care about Yellowstone and other protected wilderness areas around the world.

The Antiaircraft Journal. Volume 92, Number 4, July-August 1949

DTIC Science & Technology

1949-08-01

in Pittsburgh, Union- town, Johnstown, Altoona, Greensburg, Butler, New Castle, Sharon and Erie. Propaganda broadcasts began, adding to the panic and...Altoona, Johnstown, \\Vashington, Beaver Falls, New Castle, Sharon , Butler, and DuBois. Others blew up tele- phone exchanges, power stations and bridges. 1...5.00 Omaha Beachhead fWD Historical) .. _ . _. _ ’" 1.75 Purple Heart Valrey ( Bourke -White) 3.00 Saint lo (Official) 1.25 Salerno (Official) 60 The

The Soviet Stealth Fighter: Check or Checkmate

DTIC Science & Technology

1988-04-01

pp. 20-31. 25 11. Bussert, Jim and Paul Beaver. "Soviet Submarine Hull Coatings," Defense Electronics (August 1987), pp. 26-27. 12. Canan , James W...Aircraft (January 1987), pp. 50-59. 34. Vorobyov, Ivan , Major-General. "Formula for Victory," Soviet Military Review (November 1986), pp. 14-15. 35...34Stealth Somber Taking Shape," International Combat Aircraft (September 1987), pp. 27-31. Vozobyov, Ivan , Major-General. "New Weapons Require Sound

Naval Law Review. Volume 64, 2015

DTIC Science & Technology

2016-03-16

Supreme Court noted that concepts of ownership of or title to natural resources such as natural gas, minerals, landfill areas, birds, fish and other...unappropriated water is consistent with the approach the Supreme Court has taken in cases involving the use or disposition of water in the Western states.6...existing rights.12 In California Oregon Power Co. v. Beaver Portland Cement Co., the Supreme Court held that the effect of the Desert Land Act was

Archaeological Inventory and Testing of Prehistoric Habitation Sites, Chief Joseph Dam Project, Washington.

DTIC Science & Technology

1985-01-01

Abundance1 Seasonality2 Yellow - bellied marmot Marmota fleviventnis Common Resident Least chipmunk Eutamias minimus Rare Resident Yellow pine chipmunk...sp. Jackcrabbit 6SYMLrlaua null L4 Nuttall cottontal 6 Manmota #a~diwnfri Yellow - bellied marmot 57 Castor canadensis Beaver 6 Oiidai zibeftec Muskrat... marmot , cottontails, ground squirrels, and badgers commonly dwell near the river. The uplands of Zone IV probably always were Because of their abundance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cao, Yong; Chu, Yuchuan; He, Xiaoming

This paper proposes a domain decomposition method for the coupled stationary Navier-Stokes and Darcy equations with the Beavers-Joseph-Saffman interface condition in order to improve the efficiency of the finite element method. The physical interface conditions are directly utilized to construct the boundary conditions on the interface and then decouple the Navier-Stokes and Darcy equations. Newton iteration will be used to deal with the nonlinear systems. Numerical results are presented to illustrate the features of the proposed method.

Assessment of conservation easements, total phosphorus, and total suspended solids in West Fork Beaver Creek, Minnesota, 1999-2012

USGS Publications Warehouse

Christensen, Victoria G.; Kieta, Kristen A.

2014-01-01

This study examined conservation easements and their effectiveness at reducing phosphorus and solids transport to streams. The U.S. Geological Survey cooperated with the Minnesota Board of Water and Soil Resources and worked collaboratively with the Hawk Creek Watershed Project to examine the West Fork Beaver Creek Basin in Renville County, which has the largest number of Reinvest In Minnesota land retirement contracts in the State (as of 2013). Among all conservation easement programs, a total of 24,218 acres of agricultural land were retired throughout Renville County, and 2,718 acres were retired in the West Fork Beaver Creek Basin from 1987 through 2012. Total land retirement increased steadily from 1987 until 2000. In 2000, land retirement increased sharply because of the Minnesota River Conservation Reserve Enhancement Program, then leveled off when the program ended in 2002. Streamflow data were collected during 1999 through 2011, and total phosphorus and total suspended solids data were collected during 1999 through 2012. During this period, the highest peak streamflow of 1,320 cubic feet per second was in March 2010. Total phosphorus and total suspended solids are constituents that tend to increase with increases in streamflow. Annual flow-weighted mean total-phosphorus concentrations ranged from 0.140 to 0.759 milligrams per liter, and annual flow-weighted mean total suspended solids concentrations ranged from 21.3 to 217 milligrams per liter. Annual flow-weighted mean total phosphorus and total suspended solids concentrations decreased steadily during the first 4 years of water-quality sample collection. A downward trend in flow-weighted mean total-phosphorus concentrations was significant from 1999 through 2008; however, flow-weighted total-phosphorus concentrations increased substantially in 2009, and the total phosphorus trend was no longer significant. The high annual flow-weighted mean concentrations for total phosphorus and total suspended solids in 2009 were affected by outlier concentrations documented in March 2009. Agricultural land-retirement data only were available through 2008; therefore, it was not possible to compare total phosphorus and total suspended solids concentrations to agricultural land-retirement data for 2009–11. A downward trend in annual flow-weighted mean total-phosphorus concentrations was related significantly to annual land retirement for 1999–2008. The relation between annual flow-weighted mean total suspended solids concentration and annual land retirement was not statistically significant for 1999–2008. If land-retirement data had been available for 2009–11, it is possible that the relation between total phosphorus and land retirement would no longer be evident because of the marked increase in flow-weighted concentrations during 2009. Alternatively, the increase in annual flow-weighted mean total-phosphorus concentrations during 2009–11 may be because of other factors, including industrial discharges, increases in drain tile installation, changes in land use including decreases in agricultural land retirement after 2008, increases in erosion, increases in phosphorus applications to fields, or unknown causes. Inclusion of land-retirement effects in agency planning along with other factors adds perspective with regard to the broader picture of interdependent systems and allows agencies to make informed decisions on the benefits of perpetual easements compared to limited duration easements.

Predicting spread of invasive exotic plants into de-watered reservoirs following dam removal on the Elwha River, Olympic National Park, Washington

USGS Publications Warehouse

Woodward, Andrea; Torgersen, Christian E.; Chenoweth, Joshua; Beirne, Katherine; Acker, Steve

2011-01-01

The National Park Service is planning to start the restoration of the Elwha River ecosystem in Olympic National Park by removing two high head dams beginning in 2011. The potential for dispersal of exotic plants into dewatered reservoirs following dam removal, which would inhibit restoration of native vegetation, is of great concern. We focused on predicting long-distance dispersal of invasive exotic plants rather than diffusive spread because local sources of invasive species have been surveyed. We included the long-distance dispersal vectors: wind, water, birds, beavers, ungulates, and users of roads and trails. Using information about the current distribution of invasive species from two surveys, various geographic information system techniques and models, and statistical methods, we identified high-priority areas for Park staff to treat prior to dam removal, and areas of the dewatered reservoirs at risk after dam removal.

Geophysical Investigation in Support of Beaver Dam Comprehensive Seepage Investigation.

DTIC Science & Technology

1988-05-01

pervasive rather than occurring in a few well defined cond’iits. Ceophyslea1 evidonce su-- gests that the south bounding fault may act as a broad ...K. Butler, Messrs. J. R. Curro, Jr., J. L. Llopis, D. E. Yule, and M. K. Sharp , EEGD. Messrs. C. M. Deaver and S. C. Hartung, SWL, supervised the...measures. These measurements were accomplished by installing two weirs , a Parshall flume, and twenty-seven piezometers. The data suggested that the

Characterization of the Suspended-Sediment Regime and Bed-Material Gradation of the Mississippi River Basin. Potamology Program (P-I). Report 1, Volume II.

DTIC Science & Technology

1981-08-01

assembling stores at Presque Isle (present site of Erie , Pa.) and building fortifications along the Allegheny. The French also formu- lated plans to...Steubenville-Weirton North Carolina Asheville Pennsylvania Erie Johnstown Pittsburgh D36 State(s) SMSA Tennessee Knoxville Nashville-Davidson...result of lumbering, farming, and mining activi- ties. The Beaver River drainage, situated in northeastern Ohio and northwestern Pennsylvania , covers 3130

Reduced SWAP-C VICTORY Services Execution and Performance Evaluation

DTIC Science & Technology

2012-08-01

NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) UBT, Inc.,3250 W Big Beaver Rd, Suite 329, Troy ,Mi,48084 8. PERFORMING...Symposium August 14-16 Troy , Michigan 14. ABSTRACT -Executing multiple VICTORY data services, and reading multiple VICTORY-compliant sensors at the...same time resulted in the following performance measurements for the system -0.64 Amps / 3.15 Watts Power Consumption at run-time. -Roughly 0.77% System

On the Quasimonotonicity of a Square Linear Operator with Respect to a Nonnegative Cone

DTIC Science & Technology

1998-06-01

follows from the result from Perron (1907) and Frobenius (1912) on the theory of nonnegative matrices, which states that a nonnegative matrix has a...Dissertation 4. TITLE AND SUBTITLE ON THE QUASIMONOTONICITY OF A SQUARE LINEAR OPERATOR WITH RESPECT TO A NONNEGATIVE CONE 6. AUTHOR(S) Beaver, Philip...ABSTRACT (maximum 200 words) The question of when a square, linear operator is quasimonotone nondecreasing with respect to a nonnegative cone was posed for

Collection of Short Papers on the Beaver Creek Watershed Study in West Tennessee, 1989-94

DTIC Science & Technology

1995-01-01

kilogram per hectare (kg/ha) of the active ingredient. Upon contact with soil moisture, aldicarb is released. Plant uptake is generally less than 5 percent...conditions during the sampling period (dry season), (3) the absence of on-going agricultural activities that could affect nitrate concentrations ( planting ...Center Denver, Colorado 80225 In 1989, the U.S. Geological Survey began a scientific investigation to evaluate the effect of agricultural activities on

Taxonomic differences of gut microbiomes drive cellulolytic enzymatic potential within hind-gut fermenting mammals.

PubMed

Finlayson-Trick, Emma C L; Getz, Landon J; Slaine, Patrick D; Thornbury, Mackenzie; Lamoureux, Emily; Cook, Jamie; Langille, Morgan G I; Murray, Lois E; McCormick, Craig; Rohde, John R; Cheng, Zhenyu

2017-01-01

Host diet influences the diversity and metabolic activities of the gut microbiome. Previous studies have shown that the gut microbiome provides a wide array of enzymes that enable processing of diverse dietary components. Because the primary diet of the porcupine, Erethizon dorsatum, is lignified plant material, we reasoned that the porcupine microbiome would be replete with enzymes required to degrade lignocellulose. Here, we report on the bacterial composition in the porcupine microbiome using 16S rRNA sequencing and bioinformatics analysis. We extended this analysis to the microbiomes of 20 additional mammals located in Shubenacadie Wildlife Park (Nova Scotia, Canada), enabling the comparison of bacterial diversity amongst three mammalian taxonomic orders (Rodentia, Carnivora, and Artiodactyla). 16S rRNA sequencing was validated using metagenomic shotgun sequencing on selected herbivores (porcupine, beaver) and carnivores (coyote, Arctic wolf). In the microbiome, functionality is more conserved than bacterial composition, thus we mined microbiome data sets to identify conserved microbial functions across species in each order. We measured the relative gene abundances for cellobiose phosphorylase, endoglucanase, and beta-glucosidase to evaluate the cellulose-degrading potential of select mammals. The porcupine and beaver had higher proportions of genes encoding cellulose-degrading enzymes than the Artic wolf and coyote. These findings provide further evidence that gut microbiome diversity and metabolic capacity are influenced by host diet.

Taxonomic differences of gut microbiomes drive cellulolytic enzymatic potential within hind-gut fermenting mammals

PubMed Central

Thornbury, Mackenzie; Lamoureux, Emily; Cook, Jamie; Langille, Morgan G. I.; Murray, Lois E.; McCormick, Craig; Rohde, John R.

2017-01-01

Host diet influences the diversity and metabolic activities of the gut microbiome. Previous studies have shown that the gut microbiome provides a wide array of enzymes that enable processing of diverse dietary components. Because the primary diet of the porcupine, Erethizon dorsatum, is lignified plant material, we reasoned that the porcupine microbiome would be replete with enzymes required to degrade lignocellulose. Here, we report on the bacterial composition in the porcupine microbiome using 16S rRNA sequencing and bioinformatics analysis. We extended this analysis to the microbiomes of 20 additional mammals located in Shubenacadie Wildlife Park (Nova Scotia, Canada), enabling the comparison of bacterial diversity amongst three mammalian taxonomic orders (Rodentia, Carnivora, and Artiodactyla). 16S rRNA sequencing was validated using metagenomic shotgun sequencing on selected herbivores (porcupine, beaver) and carnivores (coyote, Arctic wolf). In the microbiome, functionality is more conserved than bacterial composition, thus we mined microbiome data sets to identify conserved microbial functions across species in each order. We measured the relative gene abundances for cellobiose phosphorylase, endoglucanase, and beta-glucosidase to evaluate the cellulose-degrading potential of select mammals. The porcupine and beaver had higher proportions of genes encoding cellulose-degrading enzymes than the Artic wolf and coyote. These findings provide further evidence that gut microbiome diversity and metabolic capacity are influenced by host diet. PMID:29281673

The Pliocene High Arctic terrestrial palaeoenvironmental record and the development of the western Canadian Arctic coastal plain

NASA Astrophysics Data System (ADS)

Rybczynski, N.; Braschi, L.; Gosse, J. C.; Kennedy, C.; Fraser, D.; Lakeman, T.

2013-12-01

The Pliocene fossil record of the High Arctic is represented by a collection of sites that occur across the Canadian Arctic Archipelago (CAA), with deposits in the west comprising a 1200 km-long dissected clastic wedge (Beaufort Formation) and those in the east represented by high terrace gravel deposits. Fossil material from these sites is often very well preserved and provides evidence of a boreal-type forest. In the eastern Arctic our research sites includes the Fyles Leaf Bed (FLB) and the Beaver Pond (BP) sites, on west central Ellesmere Island. These are about 10 km apart and preserve evidence of forest and peatlands. The BP fossil site preserves the remains of fossil vertebrates including fish, frog, horse, beaver, deerlet, and black bear, consistent with a boreal type forest habitat. The FLB site has recently yielded the first fossil evidence for a High Arctic camel, identified with the help of collagen fingerprinting from a fragmentary limb bone (tibia). Although modern camels live in open habitats, biogeographic and comparative dental evidence, in combination, suggest that the North American Arctic camels were browsers, and therefore forest-dwelling. Paleoenvironmental reconstruction of the Ellesmere sites has yielded a Mean Annual Temperature of between 14 to 22 degrees Celsius warmer than today. Minimum cosmogenic nuclide burial ages of 3.4 and 3.8 Ma obtained for the BP and FLB sites, respectively, are consistent with vertebrate and floral biostratigraphic evidence. The Beaufort Formation, located in the Western CAA, was formed by a regional northwesterly flowing braided fluvial system. The Beaufort Formation appears to have filled at least the western portions of the 100 km-wide channels that currently separate the islands of the CAA. Intervals of Pliocene continental-shelf progradation are recorded in the lower Iperk Formation, which is situated offshore and includes complex sigmoid-oblique clinoforms indicative of high-energy, coarse-clastic, deltaic sedimentation. A key objective of our research is to derive new age estimates and improved correlations between the eastern Arctic deposits, Beaufort and Iperk Formations in order to test different hypotheses to explain the nature of the dramatic landscape changes that were responsible for deposition of the Beaufort Formation and infilling of the CAA channels. For example, if the channels of the modern CAA function as a heat source during winter months and a heat sink during summer months, infilling of the CAA channels in the Pliocene by the Beaufort Formation may have functioned to shut down this radiative process, resulting in increased continentality.

MX Missile MOA Between Four Corners Regional Commission and the United States Air Force.

DTIC Science & Technology

1981-08-20

Mountains east of Beaver. The impact of hunting pres- sure and potential poaching has also ncz been addressed. 0 Despite the fact that phea- sant... impacted by both increased hunting pressure and poach - ing. Pheasant populations in the Delta area will be impacted by the loss of habitat due to...go. Water 0’ is very limiting. 4-780 1 Upland game birds will be impacted by both increased hunting pressure and poach - ing. Pheasant populations in

Learning from Experience: The Public Health Response to West Nile Virus, SARS, Monkeypox, and Hepatitis A Outbreaks in the United States

DTIC Science & Technology

2005-01-01

chickens in May and June 2002, with the first human cases showing up in hospital emergency departments in July. The Louisiana outbreak lasted until... Mexico , that had been used in a salsa served in a Beaver County restaurant. A total of 660 cases were reported, resulting in 3 deaths. Table...imported from Africa Contaminated green onions imported from Mexico Transmission Vector-borne (mosquitoes) Respiratory droplets (person-to

National Program for Inspection of Non-Federal Dams. Beaver Dam Lake Dam (CT 00083), Housatonic River Basin, Stratford, Connecticut. Phase I Inspection Report.

DTIC Science & Technology

1979-05-01

b. Weir and Training Walls Flash board pins ( rebars ) attached to weir crest -. General Condition of Concrete Masonry cut stone weir Rust or...None apparent Pavement Condition Not paved, grass, some -:osion due to traffic .. *.EI Movement or Settlement of Crest Evidence of past movement of...Condition at Abutment and at Concrete Good ,EI Structures -EI Indications of Movement of Structural Approximately 3" of movement of Items on Slopes gate

Response of the Cardiovascular System to Vibration and Combined Stresses

DTIC Science & Technology

1976-09-30

8217?rb tech:ical report has bsen reviewed and isapproved for public release IAW AFvR 190-12 (Tb).DLtrlbutlon Is unlimited* A. D . BLOSE Technical...8217 i𔃺 ft! 7 1 ACKNOWLEDGEMENTS It is a pleasure to acknowledge the collaborative efforts of D . Randall, Ph.D., Department of Physiology and...Coordinator: J. Evans, M.S.; Ph.D. Candidate: J. Marquis; Surgical I Technicians: C. Woolfolk and D . Cloyd; Data Analysts: T. Lowery, B.S., S. Beaver, B.S., M

Performance of an Embedded Platform Aggregating and Executing Core Vehicular Interation for C4ISR/EW Interoperability (VICTORY) Services

DTIC Science & Technology

2012-08-01

ELECTRONICS AND ARCHITECTURE (VEA) MINI-SYMPOSIUM AUGUST 14-16, TROY MICHIGAN Performance of an Embedded Platform Aggregating and Executing...NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) UBT Technologies,3250 W. Big Beaver Rd.,Ste. 329, Troy ,MI...Technology Symposium August 14-16 Troy , Michigan 14. ABSTRACT The Vehicular Integration for C4ISR/EW Interoperability (VICTORY) Standard adopts many

Archaeological Investigations at 3SF332: An Early Mississippian and Tenant Period Site on Cutoff Bayou, St. Francis County, Arkansas

DTIC Science & Technology

1991-06-01

Chucalissa (40SY1). Laboratory work at C.H. Nash Museum. Testing of suspected mound site near Reelfoot Lake , Obion County, Tennessee. Archaeological...geese (Branta canadensis). Fish from the larger streams, oxbow lakes , and beaver ponds, such as the flathead catfish, alligator gar, drum, buffalo...Zebree site in northeast Arkansas (Morse and Morse 1980), which is the type site for the Big Lake phase. Similar components have been recently

Archaeological Investigations at the Lewis Site (3LE266): A Twentieth- Century Black Owned Farmstead on the St. Francis Floodway, Lee County, Arkansas

DTIC Science & Technology

1992-09-01

Nash Museum. Testing of suspected mound site near Reelfoot Lake , Obion5 County, Tennessee. Archaeological surface survey of areas in Tipton County...swamps, and oxbow lakes . The areas between Crowleys Ridge. and the St.O Francis Floodway are urained by the floodway. The prime farmland east of the...as were migratory mallard ducks (Anas platyrhynchos) and canadian geese (Branta canadensis). Fish from the larger streams, oxbow lakes , and beaver

Flood Plain Information Brandywine Creek, New Castle County, Delaware.

DTIC Science & Technology

1973-07-01

The Brandywine’s course through Delaware is fairly straight and cuts through a valley of rugged terrain. The adjacent land slopes that comprise its...varies sharply in 3 distinct reaches. The upper reach from the State Line to Rockland Road falls 15.5 feet at a slope of 4.9 feet per mile. The middle...Mileage Above Drainage Area Location Mouth Tributary Total sq. Mi. sq. mi. Pennsy lvania-Del aware State Line 10.55 ... 299.9 Confluence with Beaver

Lake Superior Harbors of Refuge at Lutsen and Beaver Bay Cook and Lake Counties Minnesota.

DTIC Science & Technology

1977-12-01

attributed to the daily dumping into Lake Superior of 67,000 tons of taconite tailings by the Reserve Mining Cormpany. Reserve Mining will be totally...Reserve Mining must be given a reasonable period of time within which to change its operation to on-land disposal of taconite tailings. 2.33 While...shoreline, the city came into existence. The Reserve Mining Company began its construction of the taconite processing plant in 1951, and it went into

MX Siting Investigation. MX System Siting Summary Report. General Introduction. Volume I. Part I.

DTIC Science & Technology

1982-01-18

Mountain Spring Peak 1972 Observation Knoll 1971 Pinto Spring 1971 Steamboat Mountain 1971 Steamboat Mountain SW 1971 The Tetons 1971 Zane 1972 MX SITING...Silver Peak 1978 Stoddard Mountain 1978 Water Creek Canyon 1972 Yale Crossing 1971 49 Beaver Dam Mountains NE 1955 Central East 1972 Central West 1972...SHELTER SITE -ORIGINAL ROAD --- RESITED ROAD *• = FOUND 3 1/2" BRASS CAP SET ON 2 1/2" IRON PIPE . U.S DEPARTMENT OF THE INTERIOR. BUREAU OF LAND

Cultural Resource Survey for the Consolidated Space Operations Center Project Near Colorado Springs, El Paso County, Colorado.

DTIC Science & Technology

1982-01-01

fauna, to attract hunters prehistorically. I But as this area was not prime habitable land for humans, it probably also did not support large herds ...Rocky Mountain areas. The Archaic people were less dependent on herd movement, thus their socio-economic systems changed. This adaptation to a changing...coyotes, skunks, ground squirrels, pocket gophers, wolves, mule deer, white- tail deer, beaver, and porcupine (Larsen 1981; Goodlng 1977:4; Eddy 1981:7

Installation Restoration Program. Phase 1. Records Search, United States Air Force Academy, Colorado Springs, Colorado

DTIC Science & Technology

1984-12-01

Air F~yeb o et or Departmeri1 of Defense Copies of 0tis repon may be purchased from3 National Technical Information Service 5285 Porn Roya’ Road...squirrels and skunks. Raccoons and abert squirrel popula- tions are stable, and beaver populations are declining. Black-tailed prairie dogs and jack...on prairie dog towns, which are not found on the Academy site today. Prairie falcons are rare on the base. Two eyries with four to six birds are

Phosphate and carbonate mass balances and their relationships to ground-water inputs at Beaver Lake, Waukesha County, Wisconsin. Technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, B.E.; Cherkauer, D.S.

1991-01-01

The water and chemical budgets of Beaver Lake, Waukesha County, Wisconsin were examined to determine the role of groundwater and sediments in controlling lake quality in a seepage lake. Groundwater dominates the water budget, providing 70% of annual inflow and 60% of the outflow. The 15-m deep lake diverts flow from a depth of at least 90 m in the glacial aquifer of which it is a part. Acting as a flow-through system, the lake receives inflow predominantly from nearshore springs. Outflow occurs in the deeper parts of the lake. Groundwater provides more than 90% of the mass inflow ofmore » the major chemicals examined (Ca, Mg, Na, K, HCO3, SO4, Cl and NO3). It is also the major path of outflow for chemicals, accounting for more than 60% of the lake's loss of all the above ions except Ca and HCO3. Sedimentation of 270 + or - 82 g/sqm/yr of precominatly CaCO3 marl with significant silica and organic matter accounts for removal of 43 and 15% of the Ca and HCO3, respectively. Losses of Mg, Na, K, S and Cl to the sediment are insignificant. Data on NO3 fluxes indicate groundwater provides more N than can be accounted for in water and sediment effluxes. Seasonal denitrification in the lake's hypolimnion may account for the difference.« less

Humans in Biogeophysical Models: Colonial Period Human-Environment Interactions in the Northeastern United States

NASA Astrophysics Data System (ADS)

Parolari, A.; Greco, F.; Green, M.; Lally, M.; Hermans, C.

2008-12-01

Earth system models increasingly require representation of human activities and the important role they play in the environment. At the most fundamental level, human decisions are driven by the need to acquire basic resources - nutrients, energy, water, and space - each derived from the biogeophysical setting. Modern theories in Ecological Economics place these basic resources at the base of a consumption hierarchy (from subsistence to luxury resources) on which societies and economies are built. Human decisions at all levels of this hierarchy are driven by dynamic environmental, social, and economic factors. Therefore, models merging socio-economic and biogeophysical dynamics are required to predict the evolving relationship between humans and the hydrologic cycle. To provide an example, our study focuses on changes to the hydrologic cycle during the United States colonial period (1600 to 1800). Both direct, intentional, human water use (e.g. water supply, irrigation, or hydropower) and indirect, unintentional effects resulting from the use of other resources (e.g. deforestation or beaver trapping) are considered. We argue that water was not the limiting resource to either the Native or Colonist population growth. However, food and tobacco production and harvesting of beaver pelts led to indirect interventions and consequent changes in the hydrologic cycle. The analysis presented here suggests the importance of incorporating human decision- making dynamics with existing geophysical models to fully understand trajectories of human-environment interactions. Predictive tools of this type are critical to characterizing the long-term signature of humans on the landscape and hydrologic cycle.

Microbial community diversity patterns are related to physical and chemical differences among temperate lakes near Beaver Island, MI

PubMed Central

Hengy, Miranda H.; Horton, Dean J.; Uzarski, Donald G.

2017-01-01

Lakes are dynamic and complex ecosystems that can be influenced by physical, chemical, and biological processes. Additionally, individual lakes are often chemically and physically distinct, even within the same geographic region. Here we show that differences in physicochemical conditions among freshwater lakes located on (and around) the same island, as well as within the water column of each lake, are significantly related to aquatic microbial community diversity. Water samples were collected over time from the surface and bottom-water within four freshwater lakes located around Beaver Island, MI within the Laurentian Great Lakes region. Three of the sampled lakes experienced seasonal lake mixing events, impacting either O2, pH, temperature, or a combination of the three. Microbial community alpha and beta diversity were assessed and individual microbial taxa were identified via high-throughput sequencing of the 16S rRNA gene. Results demonstrated that physical and chemical variability (temperature, dissolved oxygen, and pH) were significantly related to divergence in the beta diversity of surface and bottom-water microbial communities. Despite its correlation to microbial community structure in unconstrained analyses, constrained analyses demonstrated that dissolved organic carbon (DOC) concentration was not strongly related to microbial community structure among or within lakes. Additionally, several taxa were correlated (either positively or negatively) to environmental variables, which could be related to aerobic and anaerobic metabolisms. This study highlights the measurable relationships between environmental conditions and microbial communities within freshwater temperate lakes around the same island. PMID:29062609

Impacts of interstate transport of pollutants on high ozone events over the Mid-Atlantic United States

NASA Astrophysics Data System (ADS)

Liao, Kuo-Jen; Hou, Xiangting; Baker, Debra Ratterman

2014-02-01

The impacts of interstate transport of anthropogenic nitrogen oxides (NOx) and volatile organic compound (VOC) emissions on peak ozone formation in four nonattainment areas (i.e., Baltimore, Philadelphia-Wilmington-Atlantic City, Pittsburgh-Beaver Valley and Washington, DC) in the Mid-Atlantic U.S. were quantified in this study. Regional air quality and sensitivities of ground-level ozone to emissions from four regions in the eastern U.S. were simulated for three summer months (June, July and August) in 2007 using the U.S. EPA's Community Multiscale Air Quality model with the decoupled direct method 3D. The emissions inventory used in this study was the 2007 Mid-Atlantic Regional Air Management Association Level 2 inventory, developed for State Implementation Plan screening modeling for the Ozone Transport Commission region. The modeling results show that responses of peak ozone levels at specific locations to emissions from EGU (i.e., electric generating unit) and non-EGU sources could be different. Therefore, emissions from EGU and non-EGU sources should be considered as two different control categories when developing regional air pollution mitigation strategies. Based on the emission inventories used in this study, reductions in anthropogenic NOx emissions (including those from EGU and non-EGU sources) from the Great Lake region as well as northeastern and southeastern U.S. would be effective for decreasing area-mean peak ozone concentrations during the summer of 2007 in the Mid-Atlantic ozone air quality nonattainment areas. The results also show that reductions in anthropogenic VOC emissions from the northeastern U.S. would also be effective for decreasing area-mean peak ozone concentrations over the Mid-Atlantic U.S. In some cases, reductions in anthropogenic NOx emissions from the Great Lake and northeastern U.S. could slightly increase area-mean peak ozone concentrations at some ozone monitors in the Pittsburgh-Beaver Valley and Washington, DC areas. However, the disbenefit of the slight increase in ozone concentrations attributed to the NOx emission controls was far outweighed by the overall ozone air quality benefits over the Mid-Atlantic region.

Investigating the anisotropy of magnetic susceptibility and other rock magnetic properties of the Beaver River Diabase in northeastern Minnesota

NASA Astrophysics Data System (ADS)

Hariri, S. H.; Brownlee, S. J.; Feinberg, J. M.; Jackson, M. J.; Miller, J. D.

2013-12-01

The Beaver River Diabase (BRD) is a series of mafic dikes and sills within the Beaver Bay Complex (BBC) of northern Minnesota, which formed during the development of the ~1.1 Ga Midcontinent Rift (MCR). The BRD is one of the youngest and most extensive intrusive phases of the BBC. The BRD dikes and sills were emplaced into the medial levels of the 6-10 kilometer-thick North Shore Volcanic Group and occur over an arcuate area extending 120 by 20 kilometers. The BRD is composed of fine- to medium-grained ophitic olivine gabbro and does not display obvious foliation or lineation features and rarely displays modal layering. Without obvious magmatic internal structures, it is difficult to determine emplacement properties such as flow direction using standard geologic mapping or petrographic techniques. For this reason, we measured the anisotropy of magnetic susceptibility (AMS), in conjunction with other rock magnetic properties, to better understand the BRD's emplacement and deformation history in the context of the MCR. AMS measures the directional dependence of low-field magnetic susceptibility, and is used to infer a shape-preferred orientation of magnetic minerals within a rock, which can be related to specific emplacement mechanisms (e.g. directional flow or settling). Preliminary analysis of AMS at 20 sites within the southern half of the BRD (with 4-7 samples per site) shows maximum susceptibility values between 4.48 x 10-6 and 2.22 x 10-4 m3/kg (1165 and 65400 μSI). Most specimens display nearly isotropic AMS ellipsoids (Pj < 1.15) with minor degrees of prolateness and oblateness. However, about 20% of specimens have higher anisotropies (Pj between 1.15 and 1.67) and higher degrees of oblateness and prolateness. Variations in AMS properties may reflect differences in concentration and composition, as well as emplacement mechanisms. Measurements of susceptibility as a function of temperature yield Curie points between 470 and 570 °C, indicating a presence of low-titanium titanomagnetite. Major hysteresis loops and first order reversal curve (FORC) experiments show coercivities between 1 and 125 mT, with a bulk average microcoercivity of 25 mT, consistent with titanomagnetite as the dominant remanence carrier. Further analysis will also investigate the relationship of AMS to rock fabric by measuring mineral crystal preferred orientations using electron backscatter diffraction. These measurements will supplement the AMS data, and provide links to the role of microstructure, texture and mineralogy in AMS.

Instream investigations in the Beaver Creek Watershed in West Tennessee, 1991-95

USGS Publications Warehouse

Byl, T.D.; Carney, K.A.

1996-01-01

The U.S. Geological Survey (USGS), in cooperation with the Tennessee Department of Agriculture, began a long-term scientific investigation in 1989 to evaluate the effect of agricultural activities on water quality and the effectiveness of agricultural best management practices in the Beaver Creek watershed, West Tennessee. In 1993 as a part of this study, the USGS, in cooperation with the Natural Resources Conservation Service, Shelby County Soil Conservation District, and the Tennessee Soybean Promotion Board, began an evaluation of the physical, chemical, biological and hydrological factors that affect water quality in streams and wetlands, and instream resource-management systems to treat agricultural nonpoint-source runoff and improve water quality. The purpose of this report is to present the results of three studies of stream and wetland investigations and a study on the transport of aldicarb from an agricultural field in the Beaver Creek watershed. A natural bottomland hardwood wetland and an artificially constructed wetland were evaluated as instream resource-management systems. These two studies showed that wetlands are an effective way to improve the quality of agricultural nonpoint-source runoff. The wetlands reduced concentrations and loads of suspended sediments, nutrients, and pesticides in the streams. A third paper documents the influence of riparian vegetation on the biological structure and water quality of a small stream draining an agricultural field. A comparison of the upper reach lined with herbaceous plants and the lower reach with mature woody vegetation showed a more stable biological community structure and Water- quality characteristics in the woody reach than in the herbaceous reach. The water-quality characteristics monitored were pH, temperature, dissolved oxygen, and specific conductance. The herbaceous reach had a greater diversity and abundance of organisms during spring and early summer, but the abundance dropped by approximately 85 percent during late summer. A fourth study describes the transport of aldicarb and its metabolites--aldicarb sulfoxide and aldicarb sulfone-in runoff at a small stream draining a cotton field. During 1991 to 1995, aldicarb and its metabolites were detected in runoff events. The highest concentrations occurred when aldicarb was applied to the field just hours before a rain storm. Aldicarb was not detectable in runoff a few weeks after application. The metabolites of aldicarb were detectable for 76 days after application. These studies demonstrate streambank vegetation and wetlands have a significant influence on stream water quality. The importance of weather conditions to herbicide application and runoff also is evident. This information can be used by resource managers to sustain and improve our Nation's streams for future generations.

Stream-sediment geochemistry in mining-impacted streams: Prichard, Eagle, and Beaver creeks, northern Coeur d'Alene Mining District, northern Idaho

USGS Publications Warehouse

Box, Stephen E.; Wallis, John C.; Briggs, Paul H.; Brown, Zoe Ann

2005-01-01

This report presents the results of one aspect of an integrated watershed-characterization study that was undertaken to assess the impacts of historical mining and milling of silver-lead-zinc ores on water and sediment composition and on aquatic biota in streams draining the northern part of the Coeur d?Alene Mining District in northern Idaho. We present the results of chemical analyses of 62 samples of streambed sediment, 19 samples of suspended sediment, 23 samples of streambank soil, and 29 samples of mine- and mill-related artificial- fill material collected from the drainages of Prichard, Eagle, and Beaver Creeks, all tributaries to the North Fork of the Coeur d?Alene River. All samples were sieved into three grain-size fractions (<0.063, 0.063?0.25, and 0.25?1.0 mm) and analyzed for 40 elements after four-acid digestion by inductively coupled plasma atomic-emission spectrometry and for mercury by continuous- flow cold-vapor atomic-absorption spectrometry in the U.S. Geological Survey laboratory in Denver, Colo. Historical mining of silver-lead-zinc ores in the headwater reaches of the Prichard Creek, Eagle Creek, and Beaver Creek drainages has resulted in enrichments of lead, zinc, mercury, arsenic, cadmium, silver, copper, cobalt, and, to a lesser extent, iron and manganese in streambed sediment. Using samples collected from the relatively unimpacted West Fork of Eagle Creek as representative of background compositions, streambed sediment in the vicinity of the mines and millsites has Pb and Zn contents of 20 to 100 times background values, decreasing to 2 to 5 times background values at the mouth of the each stream, 15 to 20 km downstream. Lesser enrichments (<10 times background values) of mercury and arsenic also are generally associated with, and decrease downstream from, historical silver-lead-zinc mining in the drainages. However, enrichments of arsenic and, to a lesser extent, mercury also are areally associated with the lode gold deposits along Prichard Creek near Murray, which were not studied here. Metal contents in samples of unfractionated suspended sediment collected during a high-flow event in April 2000 are generally similar to, but slightly higher than, those in the fine (<0.063- mm grain size) fraction of streambed sediment from the same sampling site. Although metal enrichment in streambed sediment typically begins adjacent to the mine portals and their associated mine-waste rock dumps, volumetrically larger inputs of metal-enriched materials were contributed by the ore-concentration millsites and their associated, more finely ground, more metal rich mill-tailings impoundments.

Evolutionary ecology of telomeres: a review.

PubMed

Olsson, Mats; Wapstra, Erik; Friesen, Christopher R

2018-06-01

Telomere-induced selection could take place if telomere-associated disease risk shortens reproductive life span and differently reduces relative fitness among individuals. Some of these diseases first appear before reproductive senescence and could thus influence ongoing selection. We ask whether we can estimate the components of the breeder's equation for telomeres, in which the response to selection (R, by definition "evolution") is the product of ongoing selection (S) and heritability (h 2 ). However, telomere inheritance is a conundrum: in quantitative genetics, traits can usually be allocated to categories with relatively high or low heritability, depending on their association with relative fitness. Telomere traits, however, show wide variation in heritability from zero to one, across taxa, gender, ethnicity, age, and disease status. In spite of this, there is divergence in telomere length among populations, supporting past and ongoing telomere evolution. Rates of telomere attrition and elongation vary among taxa with some, but not complete, taxonomic coherence. For example, telomerase is commonly referred to as "restricted to the germ line in mammals," but inbred mice and beavers have telomerase upregulation in somatic tissue, as do many ectotherms. These observations provoke a simplistic understanding of telomere evolutionary biology-clearly much is yet to be discovered. © 2017 The Authors. Annals of the New York Academy of Sciences published by Wiley Periodicals, Inc. on behalf of The New York Academy of Sciences.

Evaluation of improved land use data and canopy representation in BEIS with biogenic VOC measurements in California

EPA Pesticide Factsheets

The link provided access to all the datasets and metadata used in this manuscript for the model development and evaluation per Geoscientific Model Development's publication guidelines with the exception of the model output due to its size. This dataset is associated with the following publication:Bash , J., K. Baker , and M. Beaver. Evaluation of improved land use and canopy representation in BEIS v3.61 with biogenic VOC measurements in California. Geoscientific Model Development. Copernicus Publications, Katlenburg-Lindau, GERMANY, 9: 2191-2207, (2016).

Vegetation responses to natural regulation of elk in Rocky Mountain National Park

USGS Publications Warehouse

Zeigenfuss, Linda C.; Singer, Francis J.; Bowden, David

1999-01-01

Some grazing-induced responses were detected. Grazing-resistant species such as sedges (native), timothy (exotic), and club mosses increased and the amount of bare ground increased on some grazed sites. However, the changes within this sampling program alone were not alarming. The amount of bare ground increase was minor (4%), and grass and shrub cover increased in the shrub plots. The inferential power ofthis sample design was limited to the study plots only. Other factors (climate change, succession) were not controlled for using fenced plots and the sensitivity ofthe methods and plots to detect change were limited. For example, the low number oftransects in willow was not adequate to monitor conditions on the entire winter range. Lacking controls, observed changes may have been due to other factors (climate trends, beaver dam abandonment, stream channel changes), not elk herbivory alone. We recommend using a new sampling design that would include controls, pretreatment data, random site selection, and much more replication.

Analytical method for predicting the pressure distribution about a nacelle at transonic speeds

NASA Technical Reports Server (NTRS)

Keith, J. S.; Ferguson, D. R.; Merkle, C. L.; Heck, P. H.; Lahti, D. J.

1973-01-01

The formulation and development of a computer analysis for the calculation of streamlines and pressure distributions around two-dimensional (planar and axisymmetric) isolated nacelles at transonic speeds are described. The computerized flow field analysis is designed to predict the transonic flow around long and short high-bypass-ratio fan duct nacelles with inlet flows and with exhaust flows having appropriate aerothermodynamic properties. The flow field boundaries are located as far upstream and downstream as necessary to obtain minimum disturbances at the boundary. The far-field lateral flow field boundary is analytically defined to exactly represent free-flight conditions or solid wind tunnel wall effects. The inviscid solution technique is based on a Streamtube Curvature Analysis. The computer program utilizes an automatic grid refinement procedure and solves the flow field equations with a matrix relaxation technique. The boundary layer displacement effects and the onset of turbulent separation are included, based on the compressible turbulent boundary layer solution method of Stratford and Beavers and on the turbulent separation prediction method of Stratford.

Integrated Hydrogeological Investigation on the Vulnerability of a Pumping Station at a Losing Stream

NASA Astrophysics Data System (ADS)

Ngueleu Kamangou, Stephane; Vogt, Tobias; Cirpka, Olaf

2010-05-01

River restoration usually includes alteration of the river channel morphology. Thereby the interaction between river and groundwater can be modified. For the design of a river restoration project - especially in the vicinity of a groundwater pumping well for drinking water production - this impact must be predicted. But a good prediction requires a proper understanding of the existing situation. Numerical models help to improve the strategy of a successful river restoration project. The main objective of this study was to investigate the vulnerability of a pumping station located at losing river in northeast Switzerland. Besides the effect that river restoration could create, a particular attention was placed on the effect of a beaver dam in a side channel close to the pumping station. Analysis of field measurements coupled with numerical modeling of the pumping station area improved the understanding of the interactions in the river corridor between the river, side channels and the alluvial aquifer.

STC-SAB program users manual for the turbulent boundary layer and turbulent separation prediction methods employed in the NASA Langley streamtube curvature computer program

NASA Technical Reports Server (NTRS)

Ferguson, D. R.

1972-01-01

The streamtube curvature program (STC) has been developed to predict the inviscid flow field and the pressure distribution about nacelles at transonic speeds. The effects of boundary layer are to displace the inviscid flow and effectively change the body shape. Thus, the body shape must be corrected by the displacement thickness in order to calculate the correct pressure distribution. This report describes the coupling of the Stratford and Beavers boundary layer solution with the inviscid STC analysis so that all nacelle pressure forces, friction drag, and incipient separation may be predicted. The usage of the coupled STC-SAB computer program is outlined and the program input and output are defined. Included in this manual are descriptions of the principal boundary layer tables and other revisions to the STC program. The use of the viscous option is controlled by the engineer during program input definition.