Inter-Cohort Cannibalism of Early Benthic Phase Blue King Crabs (Paralithodes platypus): Alternate Foraging Strategies in Different Habitats Lead to Different Functional Responses

PubMed Central

Daly, Benjamin; Long, W. Christopher

2014-01-01

Blue king crabs (Paralithodes platypus) are commercially and ecologically important in Alaska, USA, but population abundances have fluctuated over the past several decades likely resulting from a combination of environmental and biological factors, including recruitment variability. Cannibalism between cohorts may be a source of mortality limiting recruitment success in the wild, but the degree of inter-cohort cannibalism is unknown for early benthic phase blue king crabs. In laboratory experiments, we evaluated the effects of habitat type (sand and shell) on the predator functional response and foraging behavior of year-1 blue king crabs as predators of year-0 conspecifics and examined the effects of predator presence on crypsis of prey crabs. In sand, consumption rates increased with predator size and prey density until satiation, while predation rates in shell were low regardless of predator size or prey density. These differential predation rates yielded a type III functional response in sand but a type I functional response in shell habitat. Crypsis of prey crabs was generally high and did not change in the presence of predators. Predator foraging activity was reduced in shell and may be an adaptive behavior to balance foraging efficiency and susceptibility to larger predators. Our results demonstrate that early benthic phase blue king crabs are cannibalistic between cohorts in the laboratory and that shell material is extremely effective for reducing encounter rates with conspecific predators. The distribution and abundance of such habitat may be important for recruitment success in some populations. Future studies should compare benthic habitat and species assemblages in areas with variable abundances, such as the Pribilof Islands and Saint Matthew Island in the eastern Bering Sea, to better understand possible mechanisms for recruitment variability. PMID:24558414

Occupational Exposure to Bioaerosols in Norwegian Crab Processing Plants.

PubMed

Thomassen, Marte R; Kamath, Sandip D; Lopata, Andreas L; Madsen, Anne Mette; Eduard, Wijnand; Bang, Berit E; Aasmoe, Lisbeth

2016-08-01

Aerosolization of components when processing king crab (Paralithodes camtschaticus) and edible crab (Cancer pagurus) may cause occupational health problems when inhaled by workers. A cross-sectional study was carried out in three king crab plants and one edible crab plant. Personal exposure measurements were performed throughout work shifts. Air was collected for measurement of tropomyosin, total protein, endotoxin, trypsin, and N-acetyl-β-d-glucosaminidase (NAGase). T-tests and ANOVAs were used to compare the levels of exposure in the different plants and areas in the plants. Total protein and tropomyosin levels were highest in the edible crab plant, endotoxin levels were highest in king crab plants. King crab exposure levels were highest during raw processing. Tropomyosin levels were highest during raw king crab processing with geometric mean (GM) 9.6 versus 2.5ng m(-3) during cooked processing. Conversely, edible crab tropomyosin levels were highest during cooked processing with GM 45.4 versus 8.7ng m(-3) during raw processing. Endotoxin levels were higher in king crab plants than in the edible crab plant with GM = 6285.5 endotoxin units (EU) m(-3) versus 72 EU m(-3). In the edible crab plant, NAGase levels were highest during raw processing with GM = 853 pmol4-methylumbelliferone (MU) m(-3) versus 422 pmol4-MU m(-3) during cooked processing. Trypsin activity was found in both king crab and edible crab plants and levels were higher in raw than cooked processing. Differences in exposure levels between plants and worker groups (raw and cooked processing) were identified. Norwegian crab processing workers are exposed to airborne proteins, tropomyosin, endotoxins, trypsin, and NAGase in their breathing zone. Levels vary between worker groups and factories. © The Author 2016. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Structural and functional changes of soft-bottom ecosystems in northern fjords invaded by the red king crab (Paralithodes camtschaticus)

NASA Astrophysics Data System (ADS)

Oug, Eivind; Sundet, Jan H.; Cochrane, Sabine K. J.

2018-04-01

The red king crab invaded Norwegian coastal waters in the early 1990s after having been introduced from the northern Pacific to the Russian Barents Sea coast. The crab stock increased rapidly in NE northern Norway in the latter half of the 1990s, and since 2002 there has been a commercial fishery in the eastern invaded areas. The crab is an active predator on benthic fauna especially feeding in deep soft-bottom environments. The present study is a follow-up of previous studies (2007-09) to assess the effects of the king crab predation on soft bottom species composition, ecological functioning and sediment quality. Macroinfauna (> 1 mm) was investigated in three fjord areas in the Varanger region with low, moderate and very high crab abundances, respectively. Compared with data from 1994, most benthic species were markedly reduced in abundance, in particular non-moving burrowing and tube-dwelling polychaetes, bivalves and echinoderms. However, a few species appeared to recover from 2007-09 to 2012. Changes in ecological functioning were assessed using 'biological traits analysis (BTA)'. Following the crab invasion there was a relative reduction of suspension and surface deposit feeding species, an increase in mobile and predatory organisms and an increase in those with planktotrophic larval development. From low to high crab abundances functioning changed from tube-building, deep deposit feeding and fairly large size to free-living, shallow burrowing and rather small size. With regard to sediment reworking, downward and upward conveyors were reduced whereas surficial modifiers increased. The changes imply that sediment biomixing and bioirrigation were reduced leading to a degraded sedimentary environment. It is suggested that establishing relationships between ecosystem functioning and crab abundances may form the basis for estimating ecological costs of the crab invasion. Such knowledge is important for managing the crab in the Barents Sea area being both a non

50 CFR 600.1104 - Bering Sea and Aleutian Islands (BSAI) crab species fee payment and collection system.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Pribilof blue king (the corresponding crab rationalization fishery is Pribilof red king and blue king crab), and (6) St. Matthew blue king (the corresponding crab rationalization fishery is also St. Matthew blue... Aleutian Islands red king, $237,588.04; (5) For Pribilof red king and Pribilof blue king, $1,571,216.35...

50 CFR Table 8 to Part 680 - Initial QS and PQS Pool for Each Crab QS Fishery

Code of Federal Regulations, 2011 CFR

2011-10-01

... Crab QS Fishery Crab QS Fishery Initial QS Pool Initial PQS Pool BBR Bristol Bay red king crab 400,000... 200,000,000 PIK Pribilof Islands red and blue king crab 30,000,000 30,000,000 SMB St. Matthew blue... Western Aleutian Islands red king crab 60,000,000 60,000,000 WBT Western Bering Sea Tanner crab (C. bairdi...

50 CFR Table 8 to Part 680 - Initial QS and PQS Pool for Each Crab QS Fishery

Code of Federal Regulations, 2010 CFR

2010-10-01

... Crab QS Fishery Crab QS Fishery Initial QS Pool Initial PQS Pool BBR Bristol Bay red king crab 400,000... 200,000,000 PIK Pribilof Islands red and blue king crab 30,000,000 30,000,000 SMB St. Matthew blue... Western Aleutian Islands red king crab 60,000,000 60,000,000 WBT Western Bering Sea Tanner crab (C. bairdi...

Effects of individual pre-fledging traits and environmental conditions on return patterns in juvenile king penguins.

PubMed

Saraux, Claire; Viblanc, Vincent A; Hanuise, Nicolas; Le Maho, Yvon; Le Bohec, Céline

2011-01-01

Despite the importance of early life stages in individuals' life history and population dynamics, very few studies have focused on the constraints to which these juvenile traits are subjected. Based on 10 years of automatic monitoring of over 2500 individuals, we present the first study on the effects of environmental conditions and individual pre-fledging traits on the post-fledging return of non-banded king penguins to their natal colony. Juvenile king penguins returned exclusively within one of the three austral summers following their departure. A key finding is that return rates (range 68-87%) were much higher than previously assumed for this species, importantly meaning that juvenile survival is very close to that of adults. Such high figures suggest little juvenile dispersal, and selection occurring mostly prior to fledging in king penguins. Pre-fledging conditions had a strong quadratic impact on juvenile return rates. As expected, cohorts reared under very unfavourable years (as inferred by the breeding success of the colony) exhibited low return rates but surprisingly, so did those fledged under very favourable conditions. Juvenile sojourns away from the colony were shorter under warm conditions and subsequent return rates higher, suggesting a positive effect of climate warming. The longer the post-fledging trip (1, 2 or 3 years), the earlier in the summer birds returned to their natal colony and the longer they stayed before leaving for the winter journey. The presence of juveniles in the colony was more than twice the duration required for moulting purposes, yet none attempted breeding in the year of their first return. Juvenile presence in the colony may be important for acquiring knowledge on the social and physical colonial environment and may play an important part in the learning process of mating behaviour. Further studies are required to investigate its potential implications on other life-history traits such as recruitment age.

50 CFR Table 2 to Part 680 - Crab Species Code

Code of Federal Regulations, 2010 CFR

2010-10-01

..., Table 2 Table 2 to Part 680—Crab Species Code Species code Common name Scientific name 900 Box Lopholithodes mandtii. 910 Dungeness Cancer magister. 921 Red king crab Paralithodes camtshaticus. 922 Blue king... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Crab Species Code 2 Table 2 to Part 680...

50 CFR Table 2 to Part 680 - Crab Species Code

Code of Federal Regulations, 2011 CFR

2011-10-01

..., Table 2 Table 2 to Part 680—Crab Species Code Species code Common name Scientific name 900 Box Lopholithodes mandtii. 910 Dungeness Cancer magister. 921 Red king crab Paralithodes camtshaticus. 922 Blue king... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Crab Species Code 2 Table 2 to Part 680...

No barrier to emergence of bathyal king crabs on the Antarctic shelf.

PubMed

Aronson, Richard B; Smith, Kathryn E; Vos, Stephanie C; McClintock, James B; Amsler, Margaret O; Moksnes, Per-Olav; Ellis, Daniel S; Kaeli, Jeffrey; Singh, Hanumant; Bailey, John W; Schiferl, Jessica C; van Woesik, Robert; Martin, Michael A; Steffel, Brittan V; Deal, Michelle E; Lazarus, Steven M; Havenhand, Jonathan N; Swalethorp, Rasmus; Kjellerup, Sanne; Thatje, Sven

2015-10-20

Cold-water conditions have excluded durophagous (skeleton-breaking) predators from the Antarctic seafloor for millions of years. Rapidly warming seas off the western Antarctic Peninsula could now facilitate their return to the continental shelf, with profound consequences for the endemic fauna. Among the likely first arrivals are king crabs (Lithodidae), which were discovered recently on the adjacent continental slope. During the austral summer of 2010 ‒ 2011, we used underwater imagery to survey a slope-dwelling population of the lithodid Paralomis birsteini off Marguerite Bay, western Antarctic Peninsula for environmental or trophic impediments to shoreward expansion. The population density averaged ∼ 4.5 individuals × 1,000 m(-2) within a depth range of 1,100 ‒ 1,500 m (overall observed depth range 841-2,266 m). Images of juveniles, discarded molts, and precopulatory behavior, as well as gravid females in a trapping study, suggested a reproductively viable population on the slope. At the time of the survey, there was no thermal barrier to prevent the lithodids from expanding upward and emerging on the outer shelf (400- to 550-m depth); however, near-surface temperatures remained too cold for them to survive in inner-shelf and coastal environments (<200 m). Ambient salinity, composition of the substrate, and the depth distribution of potential predators likewise indicated no barriers to expansion of lithodids onto the outer shelf. Primary food resources for lithodids--echinoderms and mollusks--were abundant on the upper slope (550-800 m) and outer shelf. As sea temperatures continue to rise, lithodids will likely play an increasingly important role in the trophic structure of subtidal communities closer to shore.

No barrier to emergence of bathyal king crabs on the Antarctic shelf

PubMed Central

Aronson, Richard B.; Smith, Kathryn E.; Vos, Stephanie C.; McClintock, James B.; Amsler, Margaret O.; Moksnes, Per-Olav; Ellis, Daniel S.; Kaeli, Jeffrey; Singh, Hanumant; Bailey, John W.; Schiferl, Jessica C.; van Woesik, Robert; Martin, Michael A.; Steffel, Brittan V.; Deal, Michelle E.; Lazarus, Steven M.; Havenhand, Jonathan N.; Swalethorp, Rasmus; Kjellerup, Sanne; Thatje, Sven

2015-01-01

Cold-water conditions have excluded durophagous (skeleton-breaking) predators from the Antarctic seafloor for millions of years. Rapidly warming seas off the western Antarctic Peninsula could now facilitate their return to the continental shelf, with profound consequences for the endemic fauna. Among the likely first arrivals are king crabs (Lithodidae), which were discovered recently on the adjacent continental slope. During the austral summer of 2010‒2011, we used underwater imagery to survey a slope-dwelling population of the lithodid Paralomis birsteini off Marguerite Bay, western Antarctic Peninsula for environmental or trophic impediments to shoreward expansion. The population density averaged ∼4.5 individuals × 1,000 m−2 within a depth range of 1,100‒1,500 m (overall observed depth range 841–2,266 m). Images of juveniles, discarded molts, and precopulatory behavior, as well as gravid females in a trapping study, suggested a reproductively viable population on the slope. At the time of the survey, there was no thermal barrier to prevent the lithodids from expanding upward and emerging on the outer shelf (400- to 550-m depth); however, near-surface temperatures remained too cold for them to survive in inner-shelf and coastal environments (<200 m). Ambient salinity, composition of the substrate, and the depth distribution of potential predators likewise indicated no barriers to expansion of lithodids onto the outer shelf. Primary food resources for lithodids—echinoderms and mollusks—were abundant on the upper slope (550–800 m) and outer shelf. As sea temperatures continue to rise, lithodids will likely play an increasingly important role in the trophic structure of subtidal communities closer to shore. PMID:26417090

Recruitment variation of eastern Bering Sea crabs: Climate-forcing or top-down effects?

NASA Astrophysics Data System (ADS)

Zheng, Jie; Kruse, Gordon H.

2006-02-01

During the last three decades, population abundances of eastern Bering Sea (EBS) crab stocks fluctuated greatly, driven by highly variable recruitment. In recent years, abundances of these stocks have been very low compared to historical levels. This study aims to understand recruitment variation of six stocks of red king ( Paralithodes camtschaticus), blue king ( P. platypus), Tanner ( Chionoecetes bairdi), and snow ( C. opilio) crabs in the EBS. Most crab recruitment time series are not significantly correlated with each other. Spatial distributions of three broadly distributed crab stocks (EBS snow and Tanner crabs and Bristol Bay red king crab) have changed considerably over time, possibly related in part to the regime shift in climate and physical oceanography in 1976-1977. Three climate-forcing hypotheses on larval survival have been proposed to explain crab recruitment variation of Bristol Bay red king crab and EBS Tanner and snow crabs. Some empirical evidence supports speculation that groundfish predation may play an important role in crab recruitment success in the EBS. However, spatial dynamics in the geographic distributions of groundfish and crabs over time make it difficult to relate crab recruitment strength to groundfish biomass. Comprehensive field and spatially explicit modeling studies are needed to test the hypotheses and better understand the relative importance and compound effects of bottom-up and top-down controls on crab recruitment.

50 CFR 600.1104 - Bering Sea and Aleutian Islands (BSAI) crab species fee payment and collection system.

Code of Federal Regulations, 2010 CFR

2010-10-01

... endorsement for Norton Sound red king. More specifically, the reduction endorsement fisheries, and the crab... endorsement fisheries, are: (1) Bristol Bay red king (the corresponding crab rationalization fishery is Bristol Bay red king crab), (2) Bering Sea and Aleutian Islands Area C. opilio and C. bairdi (the...

50 CFR 600.1104 - Bering Sea and Aleutian Islands (BSAI) crab species fee payment and collection system.

Code of Federal Regulations, 2011 CFR

2011-10-01

... endorsement for Norton Sound red king. More specifically, the reduction endorsement fisheries, and the crab... endorsement fisheries, are: (1) Bristol Bay red king (the corresponding crab rationalization fishery is Bristol Bay red king crab), (2) Bering Sea and Aleutian Islands Area C. opilio and C. bairdi (the...

50 CFR Table 2b to Part 679 - Species Codes: FMP Prohibited Species and CR Crab

Code of Federal Regulations, 2011 CFR

2011-10-01

... CR Crab 2b Table 2b to Part 679 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL... CR Crab Species Description Code CR Crab Groundfish PSC CRAB Box Lopholithodes mandtii 900... aequispinus 923 ✓ ✓ King, red Paralithodes camtshaticus 921 ✓ ✓ King, scarlet (deepsea) Lithodes couesi 924...

50 CFR Table 1 to Part 680 - Crab Rationalization (CR) Fisheries

Code of Federal Regulations, 2012 CFR

2012-10-01

... of Scotch Cap Light (164°44′ W. long.) to 53°30′ N. lat., then West to 165° W. long., (2) A western... Pribilof red king and blue king crab (Paralithodes camtshaticus and P. platypus) In waters of the EEZ with..., February 23, 1991) and NOAA Chart No. 514 (6th edition, February 16, 1991). SMB St. Matthew blue king crab...

50 CFR Table 1 to Part 680 - Crab Rationalization (CR) Fisheries

Code of Federal Regulations, 2013 CFR

2013-10-01

... of Scotch Cap Light (164°44′ W. long.) to 53°30′ N. lat., then West to 165° W. long., (2) A western... Pribilof red king and blue king crab (Paralithodes camtshaticus and P. platypus) In waters of the EEZ with..., February 23, 1991) and NOAA Chart No. 514 (6th edition, February 16, 1991). SMB St. Matthew blue king crab...

50 CFR Table 1 to Part 680 - Crab Rationalization (CR) Fisheries

Code of Federal Regulations, 2014 CFR

2014-10-01

... of Scotch Cap Light (164°44′ W. long.) to 53°30′ N. lat., then West to 165° W. long., (2) A western... Pribilof red king and blue king crab (Paralithodes camtshaticus and P. platypus) In waters of the EEZ with..., February 23, 1991) and NOAA Chart No. 514 (6th edition, February 16, 1991). SMB St. Matthew blue king crab...

50 CFR Table 1 to Part 680 - Crab Rationalization (CR) Fisheries

Code of Federal Regulations, 2010 CFR

2010-10-01

... of Scotch Cap Light (164°44′ W. long.) to 53°30′ N. lat., then West to 165° W. long., (2) A western... Pribilof red king and blue king crab (Paralithodes camtshaticus and P. platypus) In waters of the EEZ with..., February 23, 1991) and NOAA Chart No. 514 (6th edition, February 16, 1991). SMB St. Matthew blue king crab...

50 CFR Table 1 to Part 680 - Crab Rationalization (CR) Fisheries

Code of Federal Regulations, 2011 CFR

2011-10-01

... of Scotch Cap Light (164°44′ W. long.) to 53°30′ N. lat., then West to 165° W. long., (2) A western... Pribilof red king and blue king crab (Paralithodes camtshaticus and P. platypus) In waters of the EEZ with..., February 23, 1991) and NOAA Chart No. 514 (6th edition, February 16, 1991). SMB St. Matthew blue king crab...

Apparent changes in body insulation of juvenile king penguins suggest an energetic challenge during their early life at sea.

PubMed

Enstipp, Manfred R; Bost, Charles-André; Le Bohec, Céline; Bost, Caroline; Le Maho, Yvon; Weimerskirch, Henri; Handrich, Yves

2017-07-15

Little is known about the early life at sea of marine top predators, like deep-diving king penguins ( Aptenodytes patagonicus ), although this dispersal phase is probably a critical phase in their life. Apart from finding favourable foraging sites, they have to develop effective prey search patterns as well as physiological capacities that enable them to capture sufficient prey to meet their energetic needs. To investigate the ontogeny of their thermoregulatory responses at sea, we implanted 30 juvenile king penguins and 8 adult breeders with a small data logger that recorded pressure and subcutaneous temperature continuously for up to 2.5 years. We found important changes in the development of peripheral temperature patterns of foraging juvenile king penguins throughout their first year at sea. Peripheral temperature during foraging bouts fell to increasingly lower levels during the first 6 months at sea, after which it stabilized. Most importantly, these changes re-occurred during their second year at sea, after birds had fasted for ∼4 weeks on land during their second moult. Furthermore, similar peripheral temperature patterns were also present in adult birds during foraging trips throughout their breeding cycle. We suggest that rather than being a simple consequence of concurrent changes in dive effort or an indication of a physiological maturation process, these seasonal temperature changes mainly reflect differences in thermal insulation. Heat loss estimates for juveniles at sea were initially high but declined to approximately half after ∼6 months at sea, suggesting that juvenile king penguins face a strong energetic challenge during their early oceanic existence. © 2017. Published by The Company of Biologists Ltd.

Effects of Elevated CO2 and Decreased Dissolved Oxygen on Phototactic Behaviors of Juvenile Dungeness Crab (Cancer magister)

NASA Astrophysics Data System (ADS)

Imm, J.

2015-12-01

Anthropogenic CO2 emissions are increasing the concentration of CO2 in the oceans, and contributing to ocean acidification (OA), while increasing ocean temperatures and eutrophication are causing decreased levels of dissolved oxygen (DO). Due to coastal upwelling and limited water flow, the Puget Sound ecosystem is naturally high in CO2 and seasonally low in DO, making it particularly susceptible to increased acidification and hypoxia. Dungeness crabs (Cancer magister) are both ecologically and economically important to the Puget Sound region. To investigate the threat of low pH and DO to C. magister behavior, megalopae and juveniles were exposed to current and predicted future levels of pH and DO. Juveniles were then placed in a dark container with a single bright light, and movement and phototaxis were studied during three-minute trials. We hypothesized that low pH and low DO conditions would alter phototactic behaviors of juvenile C. magister, through changes in neurotransmission and metabolism. C. magister reared in control (High pH-High DO) conditions spent a greater proportion of their time near the light, and were significantly more likely to touch the light during the three-minute trial, as compared to juveniles in the other treatment conditions. These results suggest that future predicted CO2 and DO conditions in Puget Sound could disrupt the behavioral and cognitive abilities of juvenile crabs, leading to decreased survival and recruitment in the C. magister population. Given the importance of C. magister to the Puget Sound, these population changes could have significant ecological and economic implications for the region.

Effects of Elevated CO2 and Decreased Dissolved Oxygen on Phototactic Behaviors of Juvenile Dungeness Crab (Cancer magister)

NASA Astrophysics Data System (ADS)

Imm, J.

2016-02-01

Anthropogenic CO2 emissions are increasing the concentration of CO2 in the oceans, and contributing to ocean acidification (OA), while increasing ocean temperatures and eutrophication are causing decreased levels of dissolved oxygen (DO). Due to coastal upwelling and limited water flow, the Puget Sound ecosystem is naturally high in CO2 and seasonally low in DO, making it particularly susceptible to increased acidification and hypoxia. Dungeness crabs (Cancer magister) are both ecologically and economically important to the Puget Sound region. To investigate the threat of low pH and DO to C. magister behavior, megalopae and juveniles were exposed to current and predicted future levels of pH and DO. Juveniles were then placed in a dark container with a single bright light, and movement and phototaxis were studied during three-minute trials. We hypothesized that low pH and low DO conditions would alter phototactic behaviors of juvenile C. magister, through changes in neurotransmission and metabolism. C. magister reared in control (High pH-High DO) conditions spent a greater proportion of their time near the light, and were significantly more likely to touch the light during the three-minute trial, as compared to juveniles in the other treatment conditions. These results suggest that future predicted CO2 and DO conditions in Puget Sound could disrupt the behavioral and cognitive abilities of juvenile crabs, leading to decreased survival and recruitment in the C. magister population. Given the importance of C. magister to the Puget Sound, these population changes could have significant ecological and economic implications for the region.

Rearing and growth of the Octopus Robsonella fontaniana (Cephalopoda: Octopodidae) from planktonic hatchlings to benthic juveniles.

PubMed

Uriarte, Iker; Hernández, Jorge; Dörner, Jessica; Paschke, Kurt; Farías, Ana; Crovetto, Enzo; Rosas, Carlos

2010-04-01

Globally, octopus larviculture is one of the challenges faced in the attempt to diversify aquaculture and achieve cephalopod farming. Currently, only juveniles of Octopus vulgaris, Octopus joubini, and Enteroctopus dofleini have been obtained at an experimental level. This is the first study to look at the characteristics of planktonic and benthic Robsonella fontaniana juveniles in an effort to analyze the morphometric changes occurring during their planktonic and benthic phases and to explore the feasibility of obtaining settlement under controlled conditions. The morphometric measurements varied exponentially over time and did not show different tendencies before and after settlement. Mantle growth in relation to total length fit a logarithmic regression, whereas arm length and eye diameter increased linearly with respect to total length throughout the entire paralarval and juvenile periods. This suggests that the size of the mantle decreases with age in proportion to the total octopus length, whereas the organs more directly involved in catching prey tend to increase in direct proportion to the total length. The present study shows that R. fontaniana can be reared from hatching through the final paralarval stage on a diet of Lithodes santolla (king crab) zoeae; after settlement, the juveniles can be reared on a diet of crab such as Petrolisthes.

VARIATION IN GROWTH, LIPID CLASS AND FATTY ACID COMPOSITION OF THE MUD CRAB, RHITHROPANOPEUS HARRISII (GOULD) DURING LARVAL DEVELOPMENT FOLLOWING EXPOSURE TO AN INSECT JUVENILE HORMONE ANALOG (FENOXYCARB)

EPA Science Inventory

This study examines the effects of fenoxycarb?, an insect juvenile hormone analog, on larval growth, and lipid class and fatty acid composition in first crabs of the mud crab Rhithropanopeus harrisii reared through total larval development in nominal water concentrations from 1 ...

VARIATION IN GROWTH, LIPID CLASS AND FATTY ACID COMPOSITION OF THE MUD CRAB, RHITHROPANOPEUS HARRISII (GOULD) DURING LARVAL DEVELOPMENT FOLLOWING EXPOSURE TO AN INSECT JUVENILE HORMONE ANALOG (FENOXYCARB(R))

EPA Science Inventory

This study examines the effects of fenoxycarb?, an insect juvenile hormone (JH) analog, on larval growth, and lipid class and fatty acid composition in first crabs of the mud crab Rhithropanopeus harrisii reared through total larval development in nominal water concentrations fr...

Species Profiles. Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Southwest). Brown Rock Crab, Red Rock Crab, and Yellow Crab

DTIC Science & Technology

1989-12-01

staged by examining the California (Talent 1982). pleopod tips (P. Reilly, pcrs. comm.). The specific hormonal mechanisms that control molting cycles...Coos Bay, Oregon, was correlated California, they sometimes occur near the cooling water with changes in salinity ; because red rock crabs are...discharges of coastal power plants. Adams (1970) osmoconformers, survival was low at salinities below observed both juvenile and adult brown rock crabs in the

A low intensity sampling method for assessing blue crab abundance at Aransas National Wildlife Refuge and preliminary results on the relationship of blue crab abundance to whooping crane winter mortality

USGS Publications Warehouse

Pugesek, Bruce H.; Baldwin, Michael J.; Stehn, Thomas; Folk, Martin J.; Nesbitt, Stephen A.

2008-01-01

We sampled blue crabs (Callinectes sapidus) in marshes on the Aransas National Wildlife Refuge, Texas from 1997 to 2005 to determine whether whooping crane (Grus americana) mortality was related to the availability of this food source. For four years, 1997 - 2001, we sampled monthly from the fall through the spring. From these data, we developed a reduced sampling effort method that adequately characterized crab abundance and reduced the potential for disturbance to the cranes. Four additional years of data were collected with the reduced sampling effort methods. Yearly variation in crab numbers was high, ranging from a low of 0.1 crabs to a high of 3.4 crabs per 100-m transect section. Mortality among adult cranes was inversely related to crab abundance. We found no relationship between crab abundance and mortality among juvenile cranes, possibly as a result of a smaller population size of juveniles compared to adults.

Transcriptomic data analysis and differential gene expression of antioxidant pathways in king penguin juveniles (Aptenodytes patagonicus) before and after acclimatization to marine life.

PubMed

Rey, Benjamin; Dégletagne, Cyril; Duchamp, Claude

2016-12-01

In this article, we present differentially expressed gene profiles in the pectoralis muscle of wild juvenile king penguins that were either naturally acclimated to cold marine environment or experimentally immersed in cold water as compared with penguin juveniles that never experienced cold water immersion. Transcriptomic data were obtained by hybridizing penguins total cDNA on Affymetrix GeneChip Chicken Genome arrays and analyzed using maxRS algorithm , " Transcriptome analysis in non-model species: a new method for the analysis of heterologous hybridization on microarrays " (Dégletagne et al., 2010) [1] . We focused on genes involved in multiple antioxidant pathways. For better clarity, these differentially expressed genes were clustered into six functional groups according to their role in controlling redox homeostasis. The data are related to a comprehensive research study on the ontogeny of antioxidant functions in king penguins, "Hormetic response triggers multifaceted anti-oxidant strategies in immature king penguins (Aptenodytes patagonicus)" (Rey et al., 2016) [2] . The raw microarray dataset supporting the present analyses has been deposited at the Gene Expression Omnibus (GEO) repository under accessions GEO: GSE17725 and GEO: GSE82344.

Ecology and Population Dynamics of Juvenile Dungeness Crab in Grays Harbor Estuary and Adjacent Nearshore Waters of the Southern Washington Coast

DTIC Science & Technology

1989-10-01

77 5.1.2 Models of environmental and density- dependent recruitment ................................................ 80 5.2 Other Population...juvenile Dungeness crabs and flatfish ........................................ 17 Figure 1.6. Seasonal change in bottom temperature and bottom salinity ...to 2+ ............. 120 Figure 6.14. Size dependence of relative size increments per molt (expressed as a fraction of premolt size), as obtained from

Selective upregulation of lipid metabolism in skeletal muscle of foraging juvenile king penguins: an integrative study.

PubMed

Teulier, Loic; Dégletagne, Cyril; Rey, Benjamin; Tornos, Jérémy; Keime, Céline; de Dinechin, Marc; Raccurt, Mireille; Rouanet, Jean-Louis; Roussel, Damien; Duchamp, Claude

2012-06-22

The passage from shore to marine life of juvenile penguins represents a major energetic challenge to fuel intense and prolonged demands for thermoregulation and locomotion. Some functional changes developed at this crucial step were investigated by comparing pre-fledging king penguins with sea-acclimatized (SA) juveniles (Aptenodytes patagonicus). Transcriptomic analysis of pectoralis muscle biopsies revealed that most genes encoding proteins involved in lipid transport or catabolism were upregulated, while genes involved in carbohydrate metabolism were mostly downregulated in SA birds. Determination of muscle enzymatic activities showed no changes in enzymes involved in the glycolytic pathway, but increased 3-hydroxyacyl-CoA dehydrogenase, an enzyme of the β-oxidation pathway. The respiratory rates of isolated muscle mitochondria were much higher with a substrate arising from lipid metabolism (palmitoyl-L-carnitine) in SA juveniles than in terrestrial controls, while no difference emerged with a substrate arising from carbohydrate metabolism (pyruvate). In vivo, perfusion of a lipid emulsion induced a fourfold larger thermogenic effect in SA than in control juveniles. The present integrative study shows that fuel selection towards lipid oxidation characterizes penguin acclimatization to marine life. Such acclimatization may involve thyroid hormones through their nuclear beta receptor and nuclear coactivators.

Chinese mitten crab surveys of San Joaquin River basin and Suisun Marsh, California, 2000

USGS Publications Warehouse

May, Jason T.; Brown, Larry R.

2001-01-01

Juvenile Chinese mitten crabs (Eriocheir sinensis) are known to use both brackish and freshwater habitats as rearing areas. The objectives of this study were to examine the habitat use and potential effects of mitten crabs in the freshwater habitats of the San Joaquin River drainage up-stream of the Sacramento-San Joaquin Delta. After several unsuccessful attempts to catch or observe mitten crabs by trapping, electrofishing, and visual observations, the study was redirected to determine the presence of crabs in the San Joaquin River (in the vicinity of Mossdale) and Suisun Marsh. Monthly surveys using baited traps in the San Joaquin River were done from June through November 2000 and in the Suisun Marsh from August through October 2000. No mitten crabs were caught in the San Joaquin River Basin and only one mitten crab was caught in Suisun Marsh. Surveys were conducted at 92 locations in the San Joaquin River Basin by deploying 352 traps for 10,752 hours of trapping effort; in Suisun Marsh, 34 locations were investigated by deploying 150 traps for 3,600 hours of trapping effort. The baited traps captured a variety of organisms, including catfishes (Ictularidae), yellowfin gobies (Acantho-gobius flavimanus), and crayfish (Decapoda). It is unclear whether the failure to capture mitten crabs in the San Joaquin River Basin and Suisun Marsh was due to ineffective trapping methods, or repre-sents a general downward trend in populations of juvenile mitten crabs in these potential rearing areas or a temporary decline related to year-class strength. Available data (since 1998) on the number of mitten crabs entrained at federal and state fish salvage facilities indicate a downward trend in the number of crabs, which may indicate a declining trend in use of the San Joaquin River Basin by juvenile mitten crabs. Continued monitoring for juvenile Chinese mitten crabs in brackish and freshwater portions of the Sacramento-San Joaquin River Basins is needed to better assess the

Selective upregulation of lipid metabolism in skeletal muscle of foraging juvenile king penguins: an integrative study

PubMed Central

Teulier, Loic; Dégletagne, Cyril; Rey, Benjamin; Tornos, Jérémy; Keime, Céline; de Dinechin, Marc; Raccurt, Mireille; Rouanet, Jean-Louis; Roussel, Damien; Duchamp, Claude

2012-01-01

The passage from shore to marine life of juvenile penguins represents a major energetic challenge to fuel intense and prolonged demands for thermoregulation and locomotion. Some functional changes developed at this crucial step were investigated by comparing pre-fledging king penguins with sea-acclimatized (SA) juveniles (Aptenodytes patagonicus). Transcriptomic analysis of pectoralis muscle biopsies revealed that most genes encoding proteins involved in lipid transport or catabolism were upregulated, while genes involved in carbohydrate metabolism were mostly downregulated in SA birds. Determination of muscle enzymatic activities showed no changes in enzymes involved in the glycolytic pathway, but increased 3-hydroxyacyl-CoA dehydrogenase, an enzyme of the β-oxidation pathway. The respiratory rates of isolated muscle mitochondria were much higher with a substrate arising from lipid metabolism (palmitoyl-l-carnitine) in SA juveniles than in terrestrial controls, while no difference emerged with a substrate arising from carbohydrate metabolism (pyruvate). In vivo, perfusion of a lipid emulsion induced a fourfold larger thermogenic effect in SA than in control juveniles. The present integrative study shows that fuel selection towards lipid oxidation characterizes penguin acclimatization to marine life. Such acclimatization may involve thyroid hormones through their nuclear beta receptor and nuclear coactivators. PMID:22357259

Spatial dynamics of large-scale, multistage crab (Callinectes sapidus) dispersal: Determinants and consequences for recruitment

USGS Publications Warehouse

Etherington, L.L.; Eggleston, D.B.

2003-01-01

We assessed determinants and consequences of multistage dispersal on spatial recruitment of the blue crab, Callinectes sapidus, within the Croatan, Albemarle, Pamlico Estuarine System (CAPES), North Carolina, U.S.A. Large-scale sampling of early juvenile crabs over 4 years indicated that spatial abundance patterns were size-dependent and resulted from primary post-larval dispersal (pre-settlement) and secondary juvenile dispersal (early post-settlement). In general, primary dispersal led to high abundances within more seaward habitats, whereas secondary dispersal (which was relatively consistent) expanded the distribution of juveniles, potentially increasing the estuarine nursery capacity. There were strong relationships between juvenile crab density and specific wind characteristics; however, these patterns were spatially explicit. Various physical processes (e.g., seasonal wind events, timing and magnitude of tropical cyclones) interacted to influence dispersal during multiple stages and determined crab recruitment patterns. Our results suggest that the nursery value of different habitats is highly dependent on the dispersal potential (primary and secondary dispersal) to and from these areas, which is largely determined by the relative position of habitats within the estuarine landscape.

The influence of temperature and salinity on mortality of recently recruited blue crabs, Callinectes sapidus, naturally infected with Hematodinium perezi (Dinoflagellata).

PubMed

Huchin-Mian, Juan Pablo; Small, Hamish J; Shields, Jeffrey D

2018-02-01

The parasitic dinoflagellate Hematodinium perezi is highly prevalent in juvenile blue crabs, Callinectes sapidus, along the eastern seaboard of the USA. Although the parasite is known to kill adult crabs, the mortality rate of naturally infected juvenile crabs remains unknown. We analyzed the influence of temperature and salinity on the mortality of recently recruited blue crabs that were naturally infected with H. perezi. Over 492 juvenile crabs (infected, n = 282; uninfected controls, n = 210) were held individually in six-well plates and held at six temperatures (4, 10, 15, 20, 25, and 30 °C) or three salinities (5, 15, and 30 psu) for a maximum of 90 days. Mortality of infected crabs was 10 times higher at elevated temperatures (25 and 30 °C) and salinity (30 psu) compared to uninfected control treatments. By contrast, infected crabs exposed to mild temperatures (10, 15, and 20 °C) showed a high survival (>80%), no different than uninfected control treatments. Infected crabs at the lowest temperature (4 °C) exhibited a high mortality, but the intensity of infection was lower than in the other temperature treatments. In addition, this study revealed the optimal temperature (25 °C) and salinity (30 psu) for H. perezi to progress in its life cycle leading to sporulation in juvenile crabs; 31.6% (19/60) of crabs held under these conditions released dinospores of H. perezi after 10 days. Crabs held at other temperatures did not release dinospores over the time course of the experiment. Infected crabs were capable of molting and in most cases molted at the same frequency as uninfected crabs serving as controls. The mortality observed in this study indicates that early benthic juveniles will experience significant mortality due to H. perezi with increasing ocean temperatures and that this mortality may be a significant factor in the recruitment of blue crabs to high salinity regions. Copyright © 2018. Published by Elsevier Inc.

Dungeness crab survey for the Southwest Ocean Disposal Site off Grays Harbor, Washington, June 1990

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

Higgins, B.J.; Pearson, W.H.

1991-09-01

As part of the Grays Harbor Navigation Improvement Project, the Seattle District of the US Army Corps of Engineers has begun active use of the Southwest Ocean Disposal Site off Grays Harbor, Washington. This survey was to verify that the location of the area of high crab density observed during site selection surveys has not shifted into the Southeast Ocean Disposal Site. In June 1990, mean densities of juvenile Dungeness crab were 146 crab/ha within the disposal site and 609 crab/ha outside ad north of the disposal site. At nearshore locations outside the disposal site, juvenile crab density was 3275more » crab/ha. Despite the low overall abundance, the spatial distribution of crab was such that the high crab densities in 1990 have remained outside the Southwest Ocean Disposal Site. The survey data have confirmed the appropriateness of the initial selection of the disposal site boundaries and indicated no need to move to the second monitoring tier. 8 refs., 9 figs., 2 tabs.« less

50 CFR Table 36 to Part 679 - Percentage of Crab and Halibut PSC Limit Assigned to Each Amendment 80 Species

Code of Federal Regulations, 2011 CFR

2011-10-01

....47 24.19 31.72 Zone 1 Red king crab 0.14% 0.56% 6.88% 0.48% 61.79% 30.16% C. opilio crab (COBLZ) 0% 0... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Percentage of Crab and Halibut PSC Limit... Crab and Halibut PSC Limit Assigned to Each Amendment 80 Species For the following PSCspecies . . . The...

50 CFR Table 36 to Part 679 - Percentage of Crab and Halibut PSC Limit Assigned to Each Amendment 80 Species

Code of Federal Regulations, 2010 CFR

2010-10-01

....47 24.19 31.72 Zone 1 Red king crab 0.14% 0.56% 6.88% 0.48% 61.79% 30.16% C. opilio crab (COBLZ) 0% 0... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Percentage of Crab and Halibut PSC Limit... Crab and Halibut PSC Limit Assigned to Each Amendment 80 Species For the following PSCspecies . . . The...

Gill area, permeability and Na+ ,K+ -ATPase activity as a function of size and salinity in the blue crab, Callinectes sapidus.

PubMed

Li, Tiandao; Roer, Robert; Vana, Matthew; Pate, Susan; Check, Jennifer

2006-03-01

Juvenile blue crabs, Callinectes sapidus, extensively utilize oligohaline and freshwater regions of the estuary. With a presumptively larger surface-area-to-body weight ratio, juvenile crabs could experience osmo- and ionoregulatory costs well in excess of that of adults. To test this hypothesis, crabs ranging over three orders of magnitude in body weight were acclimated to either sea water (1,000 mOsm) or dilute sea water (150 mOsm), and gill surface area, water and sodium permeabilities (calculated from the passive efflux of 3H2O and 22Na+), gill Na+, K+ -ATPase activity and expression were measured. Juveniles had a relatively larger gill surface area; weight-specific gill surface area decreased with body weight. Weight-specific water and sodium fluxes also decreased with weight, but not to the same extent as gill surface area; thus juveniles were able to decrease gill permeability slightly more than adults upon acclimation to dilute media. Crabs < 5 g in body weight had markedly higher activities of gill Na+ ,K+ -ATPase than crabs > 5 g in both posterior and anterior gills. Acclimation to dilute medium induced increased expression of Na+, K+ -ATPase and enzyme activity, but the increase was not as great in juveniles as in larger crabs. The increased weight-specific surface area for water gain and salt loss for small crabs in dilute media presents a challenge that is incompletely compensated by reduced permeability and increased affinity of gill Na+, K+ -ATPase for Na+. Juveniles maintain osmotic and ionic homeostasis by the expression and utilization of extremely high levels of gill Na+, K+ -ATPase, in posterior, as well as in anterior, gills. Copyright 2006 Wiley-Liss, Inc.

Effects of acidifying ocean conditions on growth and survival of two life stages of the blue crab, Callinectes sapidus.

NASA Astrophysics Data System (ADS)

Giltz, S.; Taylor, C.

2016-02-01

Blue crabs, Callinectes sapidus, begin their larval phase offshore and circulate for approximately 30 days before settling near shore. As crabs transition to the juvenile stage, they move into coastal or estuarine environments characterized by lower salinity. Presently the average pH of the ocean is 8.1, 30% down from the beginning of the industrial revolution and is forecasted to drop to 7.8 by 2100. Decreasing pH causes dissolution of calcium carbonate shells, but the overall effects on crustaceans, such as blue crabs, are unknown. This study investigated the effect of a lower pH environment on the growth, survival, carapace hardness and molt frequency of larval and juvenile blue crabs in the Northern Gulf of Mexico. Larval crabs showed delayed growth under low pH (7.8) conditions compared to crabs in a control (present day) pH (8.1) environment. Population crashes (complete mortality) were experienced in 55% of the low pH aquaria but not in any of the control aquaria, suggesting that acidification poses a mortality risk. Under low pH conditions the intermolt duration decreased in juveniles, but the body length and weight did not differ from crabs raised in the control pH. Larvae (in tanks that did not crash) and juveniles did not experience increased mortality from a lower pH, but there do appear to be sublethal effects on growth and molting that differ between life history stages.

76 FR 68358 - Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands Crab...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-04

.... 0812081573-1645-03] RIN 0648-AX47 Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and.... SUPPLEMENTARY INFORMATION: The king and Tanner crab fisheries in the exclusive economic zone of the Bering Sea... (IFQ), which is a permit providing an exclusive harvesting privilege for a specific amount of raw crab...

78 FR 15677 - Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands Crab...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-12

...-BC25 Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands Crab... Amendment 42 to the Fishery Management Plan for Bering Sea/Aleutian Islands King and Tanner Crabs (FMP) for... economic zone of the Bering Sea and Aleutian Islands (BSAI) are managed under the FMP. The FMP was prepared...

78 FR 17341 - Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands Crab...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-21

.... 120806311-3213-01] RIN 0648-BC25 Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and... Bering Sea/Aleutian Islands King and Tanner Crabs (FMP). If approved, these regulations would revise the... of the CR Program were analyzed in the Bering Sea/Aleutian Islands Crab Fisheries Final EIS. Due to...

The relationship of blue crab abundance to winter mortality of Whooping Cranes

USGS Publications Warehouse

Pugesek, Bruce H.; Baldwin, Michael J.; Stehn, Thomas

2013-01-01

We sampled blue crab (Callinectes sapidus) numbers in marshes on the Aransas National Wildlife Refuge, Texas from 1998-2006, while simultaneously censusing the wintering population of Whooping Cranes (Grus americana) on the refuge and surrounding habitats. This was done to determine whether mortality of wintering Whooping Cranes was related to the availability of this food source. Yearly variation in crab numbers was high, ranging from a low of 0.1 crabs to a high of 3.4 crabs per 100-m transect section. Significant non-linear increases in both juvenile and adult mortality in relation to decreasing crab abundance was observed. Results suggest that some threshold of crab abundance exists in which Whooping Cranes have higher survival on their wintering grounds.

50 CFR Table 35 to Part 679 - Apportionment of Crab PSC and Halibut PSC Between the Amendment 80 and BSAI Trawl Limited Access...

Code of Federal Regulations, 2011 CFR

2011-10-01

... 35 to Part 679—Apportionment of Crab PSC and Halibut PSC Between the Amendment 80 and BSAI Trawl Limited Access Sectors Fishery Year Halibut PSC limit in the BSAI Zone 1 Red king crab PSC limit . . . C... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Apportionment of Crab PSC and Halibut PSC...

50 CFR Table 35 to Part 679 - Apportionment of Crab PSC and Halibut PSC Between the Amendment 80 and BSAI Trawl Limited Access...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 35 to Part 679—Apportionment of Crab PSC and Halibut PSC Between the Amendment 80 and BSAI Trawl Limited Access Sectors Fishery Year Halibut PSC limit in the BSAI Zone 1 Red king crab PSC limit . . . C... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Apportionment of Crab PSC and Halibut PSC...

Habitat shifts and spatial distribution of the intertidal crab Neohelice ( Chasmagnathus ) granulata Dana

NASA Astrophysics Data System (ADS)

Casariego, Agustina Mendez; Alberti, Juan; Luppi, Tomás; Daleo, Pedro; Iribarne, Oscar

2011-08-01

Intertidal zones of estuaries and embayments of the SW Atlantic are dominated by the semiterrestrial burrowing grapsid crab, Neohelice ( Chasmagnathus) granulata, and characterized by extensive mud flats surrounded by salt marshes. In this work we examined spatial patterns of distribution of N. granulata during two years to explain their movement patterns. The results of the population sampling showed segregation by sex and size throughout the intertidal, with seasonal variations in densities and different condition indices for adults and juveniles at the different zones. The comparison of seasonal activity (ambulatory activity outside burrows) between marshes and mudflats shows that short term (e.g. daily) variations in activity were controlled by tides. Crabs were active at high tides but increased their activity on days with higher tidal amplitude. Seasonal activity showed that at both areas, females remain with low activity except for a peak in winter, while males showed the highest activity during summer in the mudflat zone, but not so in the marsh. This pattern can be the response to differences in stress tolerance, suggesting that high temperatures are limiting the performance of adult crabs during summer, especially at the marsh where physical conditions can be more critical. The spatial size segregation can be explained by differential mortality in each zone (estimated with tethered crabs), and by the juvenile movement between these zones (estimated with movement traps). Juvenile mortality is higher at the mudflat, while adult mortality is higher in the marsh. Smaller juveniles moved to the marsh, where the mortality is lower, and the larger juveniles moved towards the mudflat. This mortality is due almost exclusively to cannibalism, so our results suggest that this movement of different size classes between zones is controlled, at least in part, by intraspecific predation.

Abundance of non-native crabs in intertidal habitats of New England with natural and artificial structure.

PubMed

Lovely, Christina M; O'Connor, Nancy J; Judge, Michael L

2015-01-01

Marine habitats containing complex physical structure (e.g., crevices) can provide shelter from predation for benthic invertebrates. To examine effects of natural and artificial structure on the abundance of intertidal juvenile crabs, 2 experiments were conducted in Kingston Bay, Massachusetts, USA, from July to September, 2012. In the first experiment, structure was manipulated in a two-factor design that was placed in the high intertidal for 3 one-week periods to test for both substrate type (sand vs. rock) and the presence or absence of artificial structure (mesh grow-out bags used in aquaculture, ∼0.5 m(2) with 62 mm(2) mesh openings). The Asian shore crab, Hemigrapsus sanguineus, and small individuals of the green crab, Carcinus maenas, were observed only in the treatments of rocks and mesh bag plus rocks. Most green crabs were small (<6 mm in carapace width) whereas H. sanguineus occurred in a wide range of sizes. In the second experiment, 3 levels of oyster-shell treatments were established using grow-out bags placed on a muddy sand substrate in the low intertidal zone: mesh grow-out bags without shells, grow-out bags with oyster shells, and grow-out bags containing live oysters. Replicate bags were deployed weekly for 7 weeks in a randomized complete block design. All crabs collected in the bags were juvenile C. maenas (1-15 mm carapace width), and numbers of crabs differed 6-fold among treatments, with most crabs present in bags with live oysters (29.5 ± 10.6 m(-2) [mean ± S.D.]) and fewest in bags without shells (4.9 ± 3.7 m(-2)). Both C. maenas and H. sanguineus occurred in habitats with natural structure (cobble rocks). The attraction of juvenile C. maenas to artificial structure consisting of plastic mesh bags containing both oyster shells and living oysters could potentially impact oyster aquaculture operations.

Environmentally driven shift between alternative female morphotypes in the mottled shore crab.

PubMed

Capparelli, Mariana V; Flores, Augusto A V

2011-10-01

Precocious maturity is an important life history trait and might be advantageous if the juvenile habitat is risky. Larvae of the mottled shore crab Pachygrapsus transversus settle to the benthic habitat at a very large size, undergo a brief juvenile development and mature within a few months at a size about a fourth of the asymptotic maximum size for this species. This strategy may rely on the capacity of this species to molt to a juvenile-like morphotype (mI) in which reproduction is suppressed. In the laboratory, winter temperature triggered the puberty molt for a large proportion of juveniles, and still allowed high growth rates if combined with long photoperiod. This would result in a large number of juvenile crabs to join the adult reproductive stock in spring, at the beginning of the breeding season. Adult morphs (mII) grow faster under winter conditions, and therefore might be able to direct resources to reproduction during summer. Yet, females held in captivity without any interaction with conspecifics failed to maintain their reproductive status and often reversed to mI stages. In contrast, when a potential mate was presented, all crabs held their mII status, regardless of whether interaction involved visual, visual + chemical, or visual + chemical + tactile cues. Males discriminate female morphs, and physical interactions, including the inspection of mate receptivity and copulation, took longer when they were interacting with mII females. More than a trade-off between growth and reproduction, sustaining a breeding condition in P. transversus females is apparently a bet for successful mating in the presence of a suitable male conspecific. Copyright © 2011 Elsevier GmbH. All rights reserved.

Juvenile King Scallop, Pecten maximus, Is Potentially Tolerant to Low Levels of Ocean Acidification When Food Is Unrestricted

PubMed Central

Sanders, Matthew Burton; Bean, Tim P.; Hutchinson, Thomas H.; Le Quesne, Will J. F.

2013-01-01

The decline in ocean water pH and changes in carbonate saturation states through anthropogenically mediated increases in atmospheric CO2 levels may pose a hazard to marine organisms. This may be particularly acute for those species reliant on calcareous structures like shells and exoskeletons. This is of particular concern in the case of valuable commercially exploited species such as the king scallop, Pecten maximus. In this study we investigated the effects on oxygen consumption, clearance rates and cellular turnover in juvenile P . maximus following 3 months laboratory exposure to four pCO2 treatments (290, 380, 750 and 1140 µatm). None of the exposure levels were found to have significant effect on the clearance rates, respiration rates, condition index or cellular turnover (RNA: DNA) of individuals. While it is clear that some life stages of marine bivalves appear susceptible to future levels of ocean acidification, particularly under food limiting conditions, the results from this study suggest that where food is in abundance, bivalves like juvenile P . maximus may display a tolerance to limited changes in seawater chemistry. PMID:24023928

Juvenile king scallop, Pecten maximus, is potentially tolerant to low levels of ocean acidification when food is unrestricted.

PubMed

Sanders, Matthew Burton; Bean, Tim P; Hutchinson, Thomas H; Le Quesne, Will J F

2013-01-01

The decline in ocean water pH and changes in carbonate saturation states through anthropogenically mediated increases in atmospheric CO2 levels may pose a hazard to marine organisms. This may be particularly acute for those species reliant on calcareous structures like shells and exoskeletons. This is of particular concern in the case of valuable commercially exploited species such as the king scallop, Pecten maximus. In this study we investigated the effects on oxygen consumption, clearance rates and cellular turnover in juvenile P. maximus following 3 months laboratory exposure to four pCO2 treatments (290, 380, 750 and 1140 µatm). None of the exposure levels were found to have significant effect on the clearance rates, respiration rates, condition index or cellular turnover (RNA: DNA) of individuals. While it is clear that some life stages of marine bivalves appear susceptible to future levels of ocean acidification, particularly under food limiting conditions, the results from this study suggest that where food is in abundance, bivalves like juvenile P. maximus may display a tolerance to limited changes in seawater chemistry.

Quantification of the indirect effects of scallop dredge fisheries on a brown crab fishery.

PubMed

Öndes, Fikret; Kaiser, Michel J; Murray, Lee G

2016-08-01

This study aimed to describe the characteristics of the by-catch of Cancer pagurus in king scallop dredges in the Isle of Man, and to determine the damage, immediate mortality and estimated mortality during fishing seasons associated with scallop dredges. Based on dredge surveys, spatial and seasonal variations were observed, with the highest number of crabs found off the west coast of the Isle of Man in the autumn when berried females crabs were most frequently caught. In general, female crabs comprised 84% of the catch. The damage levels of crabs was high with 45% of crabs recorded as crushed or dead or with severe damage, whilst 24% of crabs exhibited missing limbs. Estimates of the potential mortality associated with scallop dredging led to a lower and upper estimate of possible crab by-catch mortality of 15t and 24t respectively which represented 3.0-4.8% of the commercial landings of brown crab for the Isle of Man. Heaviest mortalities of crabs occurred in autumn to the west of the Isle of Man when female berried crabs move offshore into deeper water. The use of a temporary and spatially restricted scallop dredging closure could provide a simple solution to mitigate additional crab mortality in the event that scallop dredging increased beyond current levels in the future. Copyright © 2016 Elsevier Ltd. All rights reserved.

Recruitment patterns, low cannibalism and reduced interspecific predation contribute to high invasion success of two Pacific crabs in northwestern Europe

NASA Astrophysics Data System (ADS)

Geburzi, Jonas C.; Brandis, Dirk; Buschbaum, Christian

2018-01-01

Life-history traits and interactions with native species play an important role for the successful establishment of non-native species in new habitats. We investigated the recent successful invasion of the Pacific crabs Hemigrapsus takanoi and H. sanguineus to the southeastern North Sea coast with respect to their recruitment patterns, as well as interactions of juvenile with sub-adult individuals among the Pacific crabs and with native shore crabs Carcinus maenas. A field survey of juvenile native and introduced crab abundances (carapace width 1.4-10 mm) was conducted in the northern Wadden Sea, spanning 24 months from 2014 to 2016. The survey revealed different seasonal recruitment patterns of native C. maenas and both introduced Hemigrapsus species. Native shore crabs showed a single recruitment peak from June to July, while Hemigrapsus spp. mainly recruited from August to early September, but recruits occurred in low densities throughout the winter until the end of the following spring season. Field experiments on the effects of larger crabs on the recruitment intensity showed that recruitment of H. takanoi was enhanced by the presence of larger congeners, but remained unaffected by larger C. maenas. Recruitment of juvenile C. maenas, by contrast, was reduced by the presence of larger Hemigrapsus spp. Additional laboratory experiments revealed high rates of cannibalism on newly recruited C. maenas by subadult conspecifics as well as strong predation by larger Hemigrapsus spp. In contrast, newly recruited Hemigrapsus spp. had a much lower risk of being preyed on by subadult conspecifics and native shore crabs. Our results suggest that the timing of recruitment in combination with low intraspecific competition and reduced predation pressure by native shore crabs are crucial for the rapid and ongoing establishment of Hemigrapsus spp. in the Wadden Sea.

Abundance of non-native crabs in intertidal habitats of New England with natural and artificial structure

PubMed Central

Lovely, Christina M.; Judge, Michael L.

2015-01-01

Marine habitats containing complex physical structure (e.g., crevices) can provide shelter from predation for benthic invertebrates. To examine effects of natural and artificial structure on the abundance of intertidal juvenile crabs, 2 experiments were conducted in Kingston Bay, Massachusetts, USA, from July to September, 2012. In the first experiment, structure was manipulated in a two-factor design that was placed in the high intertidal for 3 one-week periods to test for both substrate type (sand vs. rock) and the presence or absence of artificial structure (mesh grow-out bags used in aquaculture, ∼0.5 m2 with 62 mm2 mesh openings). The Asian shore crab, Hemigrapsus sanguineus, and small individuals of the green crab, Carcinus maenas, were observed only in the treatments of rocks and mesh bag plus rocks. Most green crabs were small (<6 mm in carapace width) whereas H. sanguineus occurred in a wide range of sizes. In the second experiment, 3 levels of oyster-shell treatments were established using grow-out bags placed on a muddy sand substrate in the low intertidal zone: mesh grow-out bags without shells, grow-out bags with oyster shells, and grow-out bags containing live oysters. Replicate bags were deployed weekly for 7 weeks in a randomized complete block design. All crabs collected in the bags were juvenile C. maenas (1–15 mm carapace width), and numbers of crabs differed 6-fold among treatments, with most crabs present in bags with live oysters (29.5 ± 10.6 m−2 [mean ± S.D.]) and fewest in bags without shells (4.9 ± 3.7 m−2). Both C. maenas and H. sanguineus occurred in habitats with natural structure (cobble rocks). The attraction of juvenile C. maenas to artificial structure consisting of plastic mesh bags containing both oyster shells and living oysters could potentially impact oyster aquaculture operations. PMID:26401456

50 CFR 600.1103 - Bering Sea and Aleutian Islands (BSAI) Crab species program.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Bering Sea and Aleutian Islands (BSAI... PROVISIONS Specific Fishery or Program Fishing Capacity Reduction Regulations § 600.1103 Bering Sea and... Fishery Management Plan for the Bering Sea/Aleutian Islands King and Tanner Crabs pursuant to § 679.2 of...

50 CFR 600.1103 - Bering Sea and Aleutian Islands (BSAI) Crab species program.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Bering Sea and Aleutian Islands (BSAI... PROVISIONS Specific Fishery or Program Fishing Capacity Reduction Regulations § 600.1103 Bering Sea and... Fishery Management Plan for the Bering Sea/Aleutian Islands King and Tanner Crabs pursuant to § 679.2 of...

50 CFR 600.1103 - Bering Sea and Aleutian Islands (BSAI) Crab species program.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Bering Sea and Aleutian Islands (BSAI... PROVISIONS Specific Fishery or Program Fishing Capacity Reduction Regulations § 600.1103 Bering Sea and... Fishery Management Plan for the Bering Sea/Aleutian Islands King and Tanner Crabs pursuant to § 679.2 of...

50 CFR 600.1103 - Bering Sea and Aleutian Islands (BSAI) Crab species program.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Bering Sea and Aleutian Islands (BSAI... PROVISIONS Specific Fishery or Program Fishing Capacity Reduction Regulations § 600.1103 Bering Sea and... Fishery Management Plan for the Bering Sea/Aleutian Islands King and Tanner Crabs pursuant to § 679.2 of...

Salmon Supplementation Studies in Idaho Rivers; Field Activities Conducted on Clear and Pete King Creeks, 2002 Annual Report.

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

Bretz, Justin K.; Olson, Jill M.

2003-03-01

In 2002 the Idaho Fisheries Resource Office continued working as a cooperator on the Salmon Supplementation Studies in Idaho Rivers (ISS) project on Pete King and Clear creeks. Data relating to supplementation treatment releases, juvenile sampling, juvenile PIT tagging, broodstock spawning and rearing, spawning ground surveys, and snorkel surveys were used to evaluate the project data points and augment past data. Supplementation treatments included the release of 51,329 left ventral-clipped smolts into Clear Creek (750 were PIT tagged), and 12,000 unmarked coded-wire tagged parr into Pete King Creek (998 were PIT tagged). Using juvenile collection methods, Idaho Fisheries Resource Officemore » staff PIT tagged and released 579 naturally produced spring chinook juveniles in Clear Creek, and 54 on Pete King Creek, for minimum survival estimates to Lower Granite Dam. For Clear Creek, minimum survival estimates to Lower Granite Dam of hatchery produced supplementation and naturally produced PIT tagged smolts, were 36.0%, and 53.1%, respectively. For Pete King Creek, minimum survival estimates to Lower Granite Dam, of hatchery produced supplementation smolts and naturally produced smolts PIT tagged as parr and presmolts, were 18.8%, and 8.3%, respectively. Adults collected for broodstock in 2002 represented the final adult broodstock group collected for the ISS project. Twenty-six ventral clipped, and 28 natural adult spring chinook were transported above the weir. Monitoring and evaluation of spawning success was continued on Clear and Pete King creeks. A total of 69 redds were counted and 79 carcasses were recovered on Clear Creek. Two redds were observed and no carcasses were collected on Pete King Creek.« less

Clash of the crabs: Interspecific, inter-cohort competition between the native European green crab, Carcinus maenas and the exotic brush clawed crab Hemigrapsus takanoi on artificial oyster reefs

NASA Astrophysics Data System (ADS)

van den Brink, Anneke; Hutting, Samara

2017-10-01

Interaction between cohorts was investigated with juveniles of the native crab Carcinus maenas and adults of the exotic crab Hemigrapsus takanoi on artificial, intertidal oyster reefs. The reefs are occupied by C. maenas seasonally as a nursery habitat and consistently by adult H. takanoi. There was a distinct decrease in abundance of C. maenas of the same carapace width as most adult H. takanoi, suggesting competition at this size was occurring. Laboratory experiments indicated that H. takanoi was a more aggressive competitor for food and, with consistently high abundance on the reefs, may result in some exclusion of C. maenas from their nursery habitat. While total exclusion of C. maenas on the oyster reefs is unlikely, cohabitation may result in reduced population size or increased use of alternative nursery habitats.

Effects of temephos (Abate? 4E) on fiddler crabs (Uca pugnax and Uca minax) on a Delaware salt marsh

USGS Publications Warehouse

Pinkney, A.E.; McGowan, P.C.; Murphy, D.R.; Lowe, T.P.; Sparling, D.W.; Meredith, W.H.

1999-01-01

The non-target effects of temephos (as Abate 4E, 44.6% active ingredient) on fiddler crabs were examined on the salt marsh at Bombay Hook National Wildlife Refuge (NWR), near Dover, DE. Six 170 x 170 m plots were established; 3 were sprayed on 4 occasions at a rate of 1.5 fl oz/acre (0.054 kg active ingredient/ha) and 3 were controls. On each plot, marsh fiddler crab (Uca pugnax) populations were monitored by repeatedly counting the number of burrow holes in 2 counting areas marked out along tidal guts. One half of each counting area was covered with bird netting to evaluate sublethal toxic effects, which, if present, could result in increased susceptibility to bird predation. A statistically significant linear association was established between the number of holes and the number of crabs. No significant differences were found in the numbers of holes (or crabs) in the sprayed vs. control plots and in the covered vs. uncovered sections. However, survival of juvenile crabs in in situ bioassays was significantly reduced (16% lower) by the spraying. Median acetylcholinesterase activity in claw muscle of red-jointed fiddler crabs (U. minax) collected 2 days after an operational spray with Abate 4E was significantly reduced (28% lower) compared to unsprayed crabs. In view of the toxicity to juvenile crabs and the cholinesterase inhibition, we recommend continued monitoring and research for non-target impacts of Abate 4E on fiddler crabs to establish whether the reported level of cholinesterase inhibition results in acute or chronic toxicity.

78 FR 69591 - Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Halibut and Crab Prohibited...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-20

... Area AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration...\\ BSAI trawl limited access fisheries Halibut Red king crab C. bairdi (animals) mortality (mt) (animals... Deputy Director, Office of Sustainable Fisheries, National Marine Fisheries Service. [FR Doc. 2013-27779...

Ontogenetic changes in the olfactory antennules of the shore crab, Hemigrapsus oregonensis, maintain sniffing function during growth

PubMed Central

Waldrop, Lindsay D.; Hann, Miranda; Henry, Amy K.; Kim, Agnes; Punjabi, Ayesha; Koehl, M. A. R.

2015-01-01

Malacostracan crustaceans capture odours using arrays of chemosensory hairs (aesthetascs) on antennules. Lobsters and stomatopods have sparse aesthetascs on long antennules that flick with a rapid downstroke when water flows between the aesthetascs and a slow return stroke when water is trapped within the array (sniffing). Changes in velocity only cause big differences in flow through an array in a critical range of hair size, spacing and speed. Crabs have short antennules bearing dense arrays of flexible aesthetascs that splay apart during downstroke and clump together during return. Can crabs sniff, and when during ontogeny are they big enough to sniff? Antennules of Hemigrapsus oregonensis representing an ontogenetic series from small juveniles to adults were used to design dynamically scaled physical models. Particle image velocimetry quantified fluid flow through each array and showed that even very small crabs capture a new water sample in their arrays during the downstroke and retain that sample during return stroke. Comparison with isometrically scaled antennules suggests that reduction in aesthetasc flexural stiffness during ontogeny, in addition to increase in aesthetasc number and decrease in relative size, maintain sniffing as crabs grow. Sniffing performance of intermediate-sized juveniles was worse than for smaller and larger crabs. PMID:25411408

Ontogenetic changes in the olfactory antennules of the shore crab, Hemigrapsus oregonensis, maintain sniffing function during growth.

PubMed

Waldrop, Lindsay D; Hann, Miranda; Henry, Amy K; Kim, Agnes; Punjabi, Ayesha; Koehl, M A R

2015-01-06

Malacostracan crustaceans capture odours using arrays of chemosensory hairs (aesthetascs) on antennules. Lobsters and stomatopods have sparse aesthetascs on long antennules that flick with a rapid downstroke when water flows between the aesthetascs and a slow return stroke when water is trapped within the array (sniffing). Changes in velocity only cause big differences in flow through an array in a critical range of hair size, spacing and speed. Crabs have short antennules bearing dense arrays of flexible aesthetascs that splay apart during downstroke and clump together during return. Can crabs sniff, and when during ontogeny are they big enough to sniff? Antennules of Hemigrapsus oregonensis representing an ontogenetic series from small juveniles to adults were used to design dynamically scaled physical models. Particle image velocimetry quantified fluid flow through each array and showed that even very small crabs capture a new water sample in their arrays during the downstroke and retain that sample during return stroke. Comparison with isometrically scaled antennules suggests that reduction in aesthetasc flexural stiffness during ontogeny, in addition to increase in aesthetasc number and decrease in relative size, maintain sniffing as crabs grow. Sniffing performance of intermediate-sized juveniles was worse than for smaller and larger crabs. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

First year growth in the lithodids Lithodes santolla and Paralomis granulosa reared at different temperatures

NASA Astrophysics Data System (ADS)

Calcagno, J. A.; Lovrich, G. A.; Thatje, S.; Nettelmann, U.; Anger, K.

2005-10-01

The southern king crab, Lithodes santolla Molina, and stone crab, Paralomis granulosa Jacquinot, inhabit the cold-temperate waters of southernmost South America (southern Chile and Argentina), where stocks of both species are endangered by overfishing. Recent investigations have shown that these crabs show life-cycle adaptations to scarcity of food and low temperatures prevailing in subantarctic regions, including complete lecithotrophy of all larval stages and prolonged periods of brooding and longevity. However, growth and development to maturity are slow under conditions of low temperatures, which may explain the particular vulnerability of subpolar lithodids to fisheries. In the present study, juvenile L. santolla and P. granulosa were individually reared in the laboratory at constant temperatures ranging from 3-15 °C, and rates of survival and development through successive instars were monitored throughout a period of about nine months from hatching. When the experiments were terminated, L. santolla had maximally reached juvenile instar IV (at 6 °C), V (9 °C), or VII (15 °C). In P. granulosa the maximum crab instar reached was II (at 3 °C), V (6 °C), V (9 °C), or VII (15 °C). The intermoult period decreased with increasing temperature, while it increased in successively later instars. In consequence, growth rate showed highly significant differences among temperatures (P<0.001). Growth-at-moult was highest at 9 °C. Rates of survival decreased significantly in juvenile P. granulosa with increasing temperature. Only at 15 °C in L. santolla, was a significantly enhanced mortality found compared with lower temperatures. Our results indicate that juvenile stages of L. santolla and P. granulosa are well adapted to 5-10°C, the range of temperatures typically prevailing in subantarctic marine environments. In spite of causing higher mortality rates, higher rearing temperatures (12-15 °C) should accelerate the rates of growth and maturation, which may be

76 FR 65973 - Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Crab Prohibited Species...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-25

... Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce. ACTION... Sector and Non-Trawl Fisheries Prohibited species and area \\1\\ Red king C. bairdi (animals) BSAI trawl limited access fisheries Halibut mortality crab C. opilio (mt) BSAI (animals) (animals) Zone 1 COBLZ Zone...

50 CFR Table 41 to Part 679 - BSAI Crab PSC Sideboard Limits for AFA Catcher/Processors and AFA Catcher Vessels

Code of Federal Regulations, 2011 CFR

2011-10-01

... CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED... . . . Red king crab Zone 1 0.007 0.299 The PSC amount in number of animals available to trawl vessels in the...

50 CFR Table 41 to Part 679 - BSAI Crab PSC Sideboard Limits for AFA Catcher/Processors and AFA Catcher Vessels

Code of Federal Regulations, 2010 CFR

2010-10-01

... CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED... . . . Red king crab Zone 1 0.007 0.299 The PSC amount in number of animals available to trawl vessels in the...

50 CFR Table 41 to Part 679 - BSAI Crab PSC Sideboard Limits for AFA Catcher/Processors and AFA Catcher Vessels

Code of Federal Regulations, 2012 CFR

2012-10-01

... CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED... . . . Red king crab Zone 1 0.007 0.299 The PSC amount in number of animals available to trawl vessels in the...

50 CFR Table 41 to Part 679 - BSAI Crab PSC Sideboard Limits for AFA Catcher/Processors and AFA Catcher Vessels

Code of Federal Regulations, 2013 CFR

2013-10-01

... CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED... . . . Red king crab Zone 1 0.007 0.299 The PSC amount in number of animals available to trawl vessels in the...

50 CFR Table 41 to Part 679 - BSAI Crab PSC Sideboard Limits for AFA Catcher/Processors and AFA Catcher Vessels

Code of Federal Regulations, 2014 CFR

2014-10-01

... CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED... . . . Red king crab Zone 1 0.007 0.299 The PSC amount in number of animals available to trawl vessels in the...

75 FR 56483 - Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Crab and Halibut Prohibited...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-16

... AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA...\\ BSAI trawl limited access fisheries Red king crab C. opilio C. bairdi (animals) Halibut mortality... Director, Office of Sustainable Fisheries, National Marine Fisheries Service. [FR Doc. 2010-23166 Filed 9...

The sediment and hydrographic characteristics of three horseshoe crab nursery beaches in hong kong

NASA Astrophysics Data System (ADS)

Chiu, Helen M. C.; Morton, Brian

2003-04-01

Horseshoe crab juveniles have been recorded from sand and sandy-mud nursery beaches at Pak Nai (western New Territories), San Tau and Shui Hau (Lantau Island), Hong Kong. In order to provide a better understanding of these beaches and to identify those plausible factors which have made them preferred by spawning horseshoe crabs, environmental parameters, including temperature, salinity, pH and dissolved oxygen content of the water, and particle size distribution and organic matter content of the sediments at the three sites, were determined and compared. The hydrographic, and sediment data obtained for the three study sites have revealed some common environmental features. The three nursery beaches are relatively remote, and far (in Hong Kong terms) from urbanized and densely populated areas. The beaches are generally well sheltered from strong wave action and inundated regularly by estuarine waters. Horseshoe crab adults tend to select these beaches for spawning as their protected features ensures the laid eggs are less likely to be washed out of the sand, and hatched juveniles can feed on the meiofauna and grow. Sediments of the three beaches largely comprise medium-sized sand particles and are moderately sorted, suggesting medium porosity and good water permeability. Such a sand type, with the generally high oxygen levels in incursing waters, may help create a well-oxygenated micro-environment for the normal development of horseshoe crab eggs, larvae and juveniles. Lantau Island beaches at San Tau and Shui Hau are relatively free from organic pollution, as reflected in generally high dissolved oxygen level, and low BOD5 and ammonia nitrogen values. Pak Nai is, however, more polluted.

The relationship of blue crab (Callinectes sapidus) size class and molt stage to disease acquisition and intensity of Hematodinium perezi infections.

PubMed

Lycett, Kristen A; Chung, J Sook; Pitula, Joseph S

2018-01-01

In the blue crab, Callinectes sapidus, early studies suggested a relationship between smaller crabs, which molt more frequently, and higher rates of infection by the dinoflagellate parasite, Hematodinium perezi. In order to better explore the influence of size and molting on infections, blue crabs were collected from the Maryland coastal bays and screened for the presence of H. perezi in hemolymph samples using a quantitative PCR assay. Molt stage was determined by a radioimmunoassay which measured ecdysteroid concentrations in blue crab hemolymph. Differences were seen in infection prevalence between size classes, with the medium size class (crabs 61 to 90 mm carapace width) and juvenile crabs (≤ 30 mm carapace width) having the highest infection prevalence at 47.2% and 46.7%, respectively. All size classes were susceptible to infection, although fall months favored disease acquisition by juveniles, whereas mid-sized animals (31-90 mm carapace width) acquired infection predominantly in summer. Disease intensity was also most pronounced in the summer, with blue crabs > 61 mm being primary sources of proliferation. Molt status appeared to be influenced by infection, with infected crabs having significantly lower concentrations of ecdysteroids than uninfected crabs in the spring and the fall. We hypothesize that infection by H. perezi may increase molt intervals, with a delay in the spring molt cycle as an evolutionary adaptation functioning to coincide with increased host metabolism, providing optimal conditions for H. perezi propagation. Regardless of season, postmolt crabs harbored significantly higher proportions of moderate and heavy infections, suggesting that the process of ecdysis, and the postmolt recovery period, has a positive effect on parasite proliferation.

50 CFR Table 16 to Part 679 - Area Codes and Descriptions for Use With State of Alaska ADF&G Commercial Operator's Annual...

Code of Federal Regulations, 2011 CFR

2011-10-01

... Shrimp Outer Cook Inlet Shrimp Dungeness Crab King Crab Tanner Crab Miscellaneous Shellfish Salmon HH H H...) (K) GroundfishHerring King Crab Salmon Shrimp Dungeness Crab Tanner Crab Miscellaneous Shellfish KK K... 04.100 Prince William Sound (E) GroundfishHerring Shrimp Dungeness Crab King Crab Tanner Crab...

Environmental Stress and Pathogen Dynamics in the Blue Crab Callinectes sapidus

NASA Astrophysics Data System (ADS)

Sullivan, T. J.; Neigel, J.; Gelpi, C. G.

2016-02-01

The blue crab Callinectes sapidus is an ecologically and economically valuable species along the Gulf of Mexico and Atlantic coasts of North America. Throughout its range, the blue crab encounters a diverse array of parasitic and pathogenic microorganisms that have episodic and occasionally severe impacts on population numbers and viability. This makes understanding factors that influence pathogen dynamics, such as host stress, an important priority. To explore the role of environmental stress on the susceptibility of blue crabs to pathogens we screened individuals collected during the summers of 2014 and 2015 for a number of infectious agents. We sampled three life stages (megalopae, juvenile, and adult) from multiple marsh and offshore locations in Louisiana. Duration of stressful environmental conditions at each location was quantified from hourly recordings provided by the Louisiana Coastwide Reference Monitoring System. Pathogenic microorganisms were detected in crabs from multiple locations and multiple years. Some of the variability in prevalence of infection can be explained by exposure to stressful extremes of temperature and salinity during summer months.

A new PCR-based method shows that blue crabs (Callinectes sapidus (Rathbun)) consume winter flounder (Pseudopleuronectes americanus (Walbaum)).

PubMed

Collier, Jackie L; Fitzgerald, Sean P; Hice, Lyndie A; Frisk, Michael G; McElroy, Anne E

2014-01-01

Winter flounder (Pseudopleuronectes americanus) once supported robust commercial and recreational fisheries in the New York (USA) region, but since the 1990s populations have been in decline. Available data show that settlement of young-of-the-year winter flounder has not declined as sharply as adult abundance, suggesting that juveniles are experiencing higher mortality following settlement. The recent increase of blue crab (Callinectes sapidus) abundance in the New York region raises the possibility that new sources of predation may be contributing to juvenile winter flounder mortality. To investigate this possibility we developed and validated a method to specifically detect winter flounder mitochondrial control region DNA sequences in the gut contents of blue crabs. A survey of 55 crabs collected from Shinnecock Bay (along the south shore of Long Island, New York) in July, August, and September of 2011 showed that 12 of 42 blue crabs (28.6%) from which PCR-amplifiable DNA was recovered had consumed winter flounder in the wild, empirically supporting the trophic link between these species that has been widely speculated to exist. This technique overcomes difficulties with visual identification of the often unrecognizable gut contents of decapod crustaceans, and modifications of this approach offer valuable tools to more broadly address their feeding habits on a wide variety of species.

EFFECTS OF FENOXYCARB EXPOSURE ON COMPLETE LARVAL STAGES OF THE XANTHID CRAB, RHITHROPANOPEUS HARRISII

EPA Science Inventory

Pest control agents, such as juvenile hormone analogues (JHA), have been developed to limit effects on non-target organisms that co-inhabit insect pest habitats. Rhithropanopeus harrisii, an estuarine xanthid crab, was used to observe the impacts of the JHA, fenoxycarb, on the pa...

Lack of transmission of Hematodinium sp. in the blue crab Callinectes sapidus through cannibalism.

PubMed

Li, Caiwen; Wheeler, Kersten N; Shields, Jeffrey D

2011-10-06

Hematodinium spp. are parasitic dinoflagellates of marine crustaceans. Outbreaks of Hematodinium sp. have impacted commercial landings of the blue crab Callinectes sapidus in the coastal bays of Virginia and Maryland (USA), with seasonal peaks in prevalence reaching 85%. The life cycle and transmission routes of the parasite in blue crabs are poorly understood. Cannibalism and waterborne transmission may be routes of transmission, although little conclusive evidence has been reported for these modes. We examined cannibalism as a route by a series of experiments wherein we repeatedly fed adult and juvenile crabs the tissues of crabs infected with Hematodinium. In each experiment, feeding was done 3 times over the course of 1 wk. Only 2 of 120 crabs were infected within 7 to 9 d after feeding, and these 2 were likely infected prior to the experimental exposures. Crabs inoculated with hemolymph from infected donors served as positive controls. They developed infections over 11 to 21 d, indicating that the Hematodinium sp. used in the cannibalism trials was infectious at the time of inoculation. Because amphipods also harbor Hematodinium-like infections, we fed tissues of infected crabs to the estuarine amphipod Leptocheirus plumulosus. Hematodinium DNA was detected in amphipods shortly after feeding, but not in animals held for longer periods, nor was it observed in histological preparations. Amphipods did not obtain infections by scavenging infected crab tissues. Our results show that Hematodinium sp. is not effectively transmitted through ingestion of diseased tissues, indicating that cannibalism may not be a major route of transmission for Hematodinium sp. in blue crabs.

75 FR 52511 - North Pacific Fishery Management Council; Notice of Public Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-26

...; review Bristol Bay red king crab CIE report, review and recommend approaches for Tanner crab model, review and recommend approaches for Pribilof Islands blue king crab and red king crab models, receive an... Fishery Management Council's Crab Plan Team (CPT). SUMMARY: The CPT will meet September 13-16, 2010, at...

Camouflage and individual variation in shore crabs (Carcinus maenas) from different habitats.

PubMed

Stevens, Martin; Lown, Alice E; Wood, Louisa E

2014-01-01

Camouflage is widespread throughout the natural world and conceals animals from predators in a vast range of habitats. Because successful camouflage usually involves matching aspects of the background environment, species and populations should evolve appearances tuned to their local habitat, termed phenotype-environment associations. However, although this has been studied in various species, little work has objectively quantified the appearances of camouflaged animals from different habitats, or related this to factors such as ontogeny and individual variation. Here, we tested for phenotype-environment associations in the common shore crab (Carcinus maenas), a species highly variable in appearance and found in a wide range of habitats. We used field surveys and digital image analysis of the colors and patterns of crabs found in four locations around Cornwall in the UK to quantify how individuals vary with habitat (predominantly rockpool, mussel bed, and mudflat). We find that individuals from sites comprising different backgrounds show substantial differences in several aspects of color and pattern, and that this is also dependent on life stage (adult or juvenile). Furthermore, the level of individual variation is dependent on site and life stage, with juvenile crabs often more variable than adults, and individuals from more homogenous habitats less diverse. Ours is the most comprehensive study to date exploring phenotype-environment associations for camouflage and individual variation in a species, and we discuss the implications of our results in terms of the mechanisms and selection pressures that may drive this.

Camouflage and Individual Variation in Shore Crabs (Carcinus maenas) from Different Habitats

PubMed Central

Stevens, Martin; Lown, Alice E.; Wood, Louisa E.

2014-01-01

Camouflage is widespread throughout the natural world and conceals animals from predators in a vast range of habitats. Because successful camouflage usually involves matching aspects of the background environment, species and populations should evolve appearances tuned to their local habitat, termed phenotype-environment associations. However, although this has been studied in various species, little work has objectively quantified the appearances of camouflaged animals from different habitats, or related this to factors such as ontogeny and individual variation. Here, we tested for phenotype-environment associations in the common shore crab (Carcinus maenas), a species highly variable in appearance and found in a wide range of habitats. We used field surveys and digital image analysis of the colors and patterns of crabs found in four locations around Cornwall in the UK to quantify how individuals vary with habitat (predominantly rockpool, mussel bed, and mudflat). We find that individuals from sites comprising different backgrounds show substantial differences in several aspects of color and pattern, and that this is also dependent on life stage (adult or juvenile). Furthermore, the level of individual variation is dependent on site and life stage, with juvenile crabs often more variable than adults, and individuals from more homogenous habitats less diverse. Ours is the most comprehensive study to date exploring phenotype-environment associations for camouflage and individual variation in a species, and we discuss the implications of our results in terms of the mechanisms and selection pressures that may drive this. PMID:25551233

Good Crab, Bad Crab

EPA Science Inventory

Are crabs friends or foes of marsh grass, benefit or detriment to the salt marsh system? We examined Uca pugilator (sand fiddler) and Sesarma reticulatum (purple marsh crab) with Spartina patens (salt marsh hay) at two elevations (10 cm below MHW and 10 cm above MHW) in mesocosms...

Uncoupling protein and ATP/ADP carrier increase mitochondrial proton conductance after cold adaptation of king penguins.

PubMed

Talbot, Darren A; Duchamp, Claude; Rey, Benjamin; Hanuise, Nicolas; Rouanet, Jean Louis; Sibille, Brigitte; Brand, Martin D

2004-07-01

Juvenile king penguins develop adaptive thermogenesis after repeated immersion in cold water. However, the mechanisms of such metabolic adaptation in birds are unknown, as they lack brown adipose tissue and uncoupling protein-1 (UCP1), which mediate adaptive non-shivering thermogenesis in mammals. We used three different groups of juvenile king penguins to investigate the mitochondrial basis of avian adaptive thermogenesis in vitro. Skeletal muscle mitochondria isolated from penguins that had never been immersed in cold water showed no superoxide-stimulated proton conductance, indicating no functional avian UCP. Skeletal muscle mitochondria from penguins that had been either experimentally immersed or naturally adapted to cold water did possess functional avian UCP, demonstrated by a superoxide-stimulated, GDP-inhibitable proton conductance across their inner membrane. This was associated with a markedly greater abundance of avian UCP mRNA. In the presence (but not the absence) of fatty acids, these mitochondria also showed a greater adenine nucleotide translocase-catalysed proton conductance than those from never-immersed penguins. This was due to an increase in the amount of adenine nucleotide translocase. Therefore, adaptive thermogenesis in juvenile king penguins is linked to two separate mechanisms of uncoupling of oxidative phosphorylation in skeletal muscle mitochondria: increased proton transport activity of avian UCP (dependent on superoxide and inhibited by GDP) and increased proton transport activity of the adenine nucleotide translocase (dependent on fatty acids and inhibited by carboxyatractylate).

Ontogenetic scaling of the olfactory antennae and flicking behavior of the shore crab, Hemigrapsus oregonensis.

PubMed

Waldrop, Lindsay D

2013-07-01

Malacostracan crustaceans such as crabs flick antennae with arrays of olfactory sensilla called aesthetascs through the water to sense odors. Flicking by crabs consists of a quick downstroke, in which aesthetascs are deflected laterally (splayed), and a slower, reversed return stroke, in which aesthetascs clump together. This motion causes water to be flushed within and then held in between aesthetascs to deliver odor molecules to olfactory receptors. Although this odor sampling method relies on a narrow range of speeds, sizes, and specific arrangements of aesthetascs, most crabs dramatically change these during ontogeny. In this study, the morphometrics of the aesthetascs, array, and antennae and the flicking kinematics of the Oregon shore crab, Hemigrapsus oregonensis (Decapoda: Brachyura), are examined to determine their scaling relationships during ontogeny. The morphometrics of the array and antennae increase more slowly than would be predicted by isometry. Juvenile crabs' aesthetascs splay relatively further apart than adults, likely due to changing material properties of aesthetasc cuticle during growth. These results suggest that disproportionate growth and altered aesthetasc splay during flicking will mediate the size changes due to growth that would otherwise lead to a loss of function.

Salmon Supplementation Studies in Idaho Rivers; Field Activities Conducted on Clear and Pete King Creeks, 2001 Annual Report.

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

Gass, Carrie; Olson, Jim M.

2004-11-01

In 2001 the Idaho Fisheries Resource Office continued as a cooperator on the Salmon Supplementation Studies in Idaho Rivers (ISS) project on Pete King and Clear creeks. Data relating to supplementation treatment releases, juvenile sampling, juvenile PIT tagging, brood stock spawning and rearing, spawning ground surveys, and snorkel surveys were used to evaluate project data points and augment past data. Due to low adult spring Chinook returns to Kooskia National Fish Hatchery (KNFH) in brood year 1999 there was no smolt supplementation treatment release into Clear Creek in 2001. A 17,014 spring Chinook parr supplementation treatment (containing 1000 PIT tags)more » was released into Pete King Creek on July 24, 2001. On Clear Creek, there were 412 naturally produced spring Chinook parr PIT tagged and released. Using juvenile collection methods, Idaho Fisheries Resource Office staff PIT tagged and released 320 naturally produced spring Chinook pre-smolts on Clear Creek, and 16 natural pre-smolts on Pete King Creek, for minimum survival estimates to Lower Granite Dam. There were no PIT tag detections of brood year 1999 smolts from Clear or Pete King creeks. A total of 2261 adult spring Chinook were collected at KNFH. Forty-three females were used for supplementation brood stock, and 45 supplementation (ventral fin-clip), and 45 natural (unmarked) adults were released upstream of KNFH to spawn naturally. Spatial and temporal distribution of 37 adults released above the KNFH weir was determined through the use of radio telemetry. On Clear Creek, a total of 166 redds (8.2 redds/km) were observed and data was collected from 195 carcasses. Seventeen completed redds (2.1 redds/km) were found, and data was collected data from six carcasses on Pete King Creek.« less

Uncoupling protein and ATP/ADP carrier increase mitochondrial proton conductance after cold adaptation of king penguins

PubMed Central

Talbot, Darren A; Duchamp, Claude; Rey, Benjamin; Hanuise, Nicolas; Rouanet, Jean Louis; Sibille, Brigitte; Brand, Martin D

2004-01-01

Juvenile king penguins develop adaptive thermogenesis after repeated immersion in cold water. However, the mechanisms of such metabolic adaptation in birds are unknown, as they lack brown adipose tissue and uncoupling protein-1 (UCP1), which mediate adaptive non-shivering thermogenesis in mammals. We used three different groups of juvenile king penguins to investigate the mitochondrial basis of avian adaptive thermogenesis in vitro. Skeletal muscle mitochondria isolated from penguins that had never been immersed in cold water showed no superoxide-stimulated proton conductance, indicating no functional avian UCP. Skeletal muscle mitochondria from penguins that had been either experimentally immersed or naturally adapted to cold water did possess functional avian UCP, demonstrated by a superoxide-stimulated, GDP-inhibitable proton conductance across their inner membrane. This was associated with a markedly greater abundance of avian UCP mRNA. In the presence (but not the absence) of fatty acids, these mitochondria also showed a greater adenine nucleotide translocase-catalysed proton conductance than those from never-immersed penguins. This was due to an increase in the amount of adenine nucleotide translocase. Therefore, adaptive thermogenesis in juvenile king penguins is linked to two separate mechanisms of uncoupling of oxidative phosphorylation in skeletal muscle mitochondria: increased proton transport activity of avian UCP (dependent on superoxide and inhibited by GDP) and increased proton transport activity of the adenine nucleotide translocase (dependent on fatty acids and inhibited by carboxyatractylate). PMID:15146050

Flood Tide Transport of Blue Crab Postlarvae: Limitations in a Lagoonal Estuary

NASA Astrophysics Data System (ADS)

Cudaback, C.; Eggleston, D.

2005-05-01

Blue crabs, an important commercial species, spend much of their life in estuaries along the east coast. The larvae spawn at or near the ocean, but the juveniles mature in the lower salinity waters of the estuary. It is generally believed that blue crab postlarvae migrate into near surface waters on flood, possibly cued by increasing salinity, and return to the bottom on ebb. Over several tidal cycles, the postlarvae travel a significant distance up-estuary. This model applies quite well to Chesapeake Bay, which has a strong along-estuary salinity gradient and large tides, but may not apply as well to Pamlico Sound, where circulation and salinity are more wind-driven than tidal. A recently completed study (N. Reyns, PhD), indicates that postlarval blue crabs use flood tides and wind-driven currents to cross Pamlico Sound. This study was based on observations with good spatial coverage, but limited vertical and temporal resolution. We have recently completed a complementary study, sampling crab larvae around the clock at four depths at a single location. Preliminary results from the new study suggest that the crab postlarvae do swim all the way to the surface, on flood only, and that flood currents are strongest slightly below the surface. These observations suggest the utility of flood tide transport in this system. However, near bottom salinity does not seem to be driven by tides; at this point it is unclear what cue might trigger the vertical migration of the postlarvae.

Population ecology of the blue crab Callinectes danae (Crustacea: Portunidae) in a Brazilian tropical estuary.

PubMed

Araújo, Marina S L C; Barreto, Aline V; Negromonte, Aurinete O; Schwamborn, Ralf

2012-03-01

This paper aims at describing the population ecology of the swimming crab Callinectes danae Smith, 1869 in one of the most productive estuaries of Brazil, the Santa Cruz Channel. These crabs were monthly collected from January to December/2009 at four stations along the channel, two in the upper and two in the lower estuary. A total of 2373 specimens of C. danae were collected during the study. Males had a larger average carapace width than non-ovigerous females (60.0 ± 15.6 mm and 52.9 ± 12.4 mm, respectively), an adaptation that gives greater protection for females during the copulation. Overall sex ratio did not differ significantly from 1:1. However, evaluating sex-ratio by sampling area, males and juveniles of both sexes occurred preferentially in the upper estuary (p < 0.05), while adult females, including ovigerous, inhabited the lower estuary, an area of major marine influence (p < 0.05). While juveniles look for estuarine waters due to the benefit from the shelter and abundance of food, ovigerous females migrate to areas of greater depth and higher salinity in order to provide a more favorable environment for embryonic and larval development and to enhance larval dispersal. Recruitment of juveniles was continuous along the year, but intensified from March to June and, with less intensity, from October to December.

Salinity and Temperature Tolerance of the Nemertean Worm Carcinonemertes errans, an Egg Predator of the Dungeness Crab.

PubMed

Dunn, Paul H; Young, Craig M

2015-04-01

Estuaries can be harsh habitats for the marine animals that enter them, but they may also provide these species with sub-saline refuges from their parasites. The nemertean egg predator Carcinonemertes errans is known to occur less frequently and in smaller numbers on its host, the Dungeness crab Metacarcinus magister, when the hosts are found within estuaries. We examined the temperature and salinity tolerances of C. errans to determine if this observed distribution represents a true salinity refuge. We monitored the survival of juvenile and larval worms exposed to ecologically relevant salinities (5-30) and temperatures (8-20 °C) over the course of several days under laboratory conditions. Juvenile worms were unaffected by the experimental temperature levels and exhibited robustness to salinity treatments 25 and 30. However, significant mortality was seen at salinity treatments 20 and below. Larvae were less tolerant than juveniles to lowered salinity and were also somewhat more susceptible to the higher temperatures tested. Given that the Dungeness crab can tolerate forays into mesohaline (salinity 5-18) waters for several days at a time, our findings suggest that salinity gradients play an important role in creating a parasite refuge for this species within the estuaries of the Pacific Northwest. © 2015 Marine Biological Laboratory.

76 FR 5556 - Fisheries of the Exclusive Economic Zone Off Alaska; Allocating Bering Sea and Aleutian Islands...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-01

... quota (IPQ) in the Western Aleutian Islands golden king crab fishery from the West regional delivery requirements. Federal regulations require West-designated golden king crab IFQ to be delivered to a processor... disruption to the Western Aleutian Islands golden king crab fishery, while providing for the sustained...

A Lethal Virus of the Blue Crab Callinectes sapidus May Be Present Throughout its Trans-hemispheric Range

NASA Astrophysics Data System (ADS)

Schott, E. J.; Flowers, E. M.; Vinagre, A.; Brown, S.; Almeida, A.

2016-02-01

Blue crabs, Callinectes sapidus, are key epibenthic predators and support valuable fisheries throughout North and South America. On both continents, they are also used to produce soft shell crabs, a value added product. On the Atlantic coast of the USA, mortality of blue crabs in soft shell production is often 25% or greater. A majority of those crabs have been found to be infected with a reovirus lethal to blue crabs. The CsRV1 virus infects multiple ectodermal and mesodermal tissues and was first described as RLV (reo-like virus) in the late 1970s. However its potential for affecting large numbers of crabs was not fully recognized until 2010 when molecular methods were developed to study its prevalence in aquaculture and the wild. Using a sensitive Rt-qPCR assay for the virus, a multi-year survey of crabs from the mid-Atlantic USA coast and Chesapeake Bay revealed that approximately 20% of adult and juvenile crabs were positive for CsRV1 genomic RNA. If blue crabs in the wild die from CsRV1 infections as rapidly as captive infected crabs, it suggests that significant numbers of wild blue crabs die from CsRV1 infections. Crab fishery managers in the Chesapeake Bay recently recognized that there is a need to better understand the role of diseases in natural mortality. The CsRV1 virus is found in C. sapidus throughout the USA range, and has been discovered in diseased Brazilian C. sapidus from Rio Grande do Sul. Genetic analysis of the virus shows that strains of CsRV1 found in Brazil are distinct from the strains identified in the USA. This pan-hemispheric range suggests that the virus has long been a component of blue crab ecology. Much more study is needed to understand the history and impacts of CsRV1 throughout the USA, Brazil, and the vast coastline in between.

Larval salinity tolerance of the South American salt-marsh crab, Neohelice (Chasmagnathus) granulata: physiological constraints to estuarine retention, export and reimmigration

NASA Astrophysics Data System (ADS)

Anger, Klaus; Spivak, Eduardo; Luppi, Tomás; Bas, Claudia; Ismael, Deborah

2008-06-01

The semiterrestrial crab Neohelice (= Chasmagnathus) granulata (Dana 1851) is a predominant species in brackish salt marshes, mangroves and estuaries. Its larvae are exported towards coastal marine waters. In order to estimate the limits of salinity tolerance constraining larval retention in estuarine habitats, we exposed in laboratory experiments freshly hatched zoeae to six different salinities (5 32‰). At 5‰, the larvae survived for a maximum of 2 weeks, reaching only exceptionally the second zoeal stage, while 38% survived to the megalopa stage at 10‰. Shortest development and negligible mortality occurred at all higher salt concentrations. These observations show that the larvae of N. granulata can tolerate a retention in the mesohaline reaches of estuaries, with a lower limit of ca. 10 15‰. Maximum survival at 25‰ suggests that polyhaline conditions rather than an export to oceanic waters are optimal for successful larval development of this species. In another experiment, we tested the capability of the last zoeal stage (IV) for reimmigration from coastal marine into brackish waters. Stepwise reductions of salinity during this stage allowed for moulting to the megalopa at 4 10‰. Although survival was at these conditions reduced and development delayed, these results suggest that already the zoea-IV stage is able to initiate the reimmigration into estuaries. After further salinity reduction, megalopae survived in this experiment for up to >3 weeks in freshwater, without moulting to juvenile crabs. In a similar experiment starting from the megalopa stage, successful metamorphosis occurred at 4 10‰, and juvenile growth continued in freshwater. Although these juvenile crabs showed significantly enhanced mortality and smaller carapace width compared to a seawater control, our results show that the late larval and early juvenile stages of N. granulata are well adapted for successful recruitment in brackish and even limnetic habitats.

Effects of different dietary lipid sources on growth performance and tissue fatty acid composition of juvenile swimming crab Portunus trituberculatus

NASA Astrophysics Data System (ADS)

Han, Tao; Wang, Jiteng; Hu, Shuixin; Li, Xinyu; Jiang, Yudong; Wang, Chunlin

2015-07-01

This study was conducted to evaluate the effects of dietary lipid sources on the growth performance and fatty acid composition of the swimming crab, Portunus trituberculatus. Four isonitrogenous and isoenergetic experimental diets were formulated to contain four separate lipid sources, including fish, soybean, rapeseed, and linseed oils (FO, SO, RO, and LO, respectively). With three replicates of 18 crabs each for each diet, crabs (initial body weight, 17.00±0.09 g) were fed twice daily for 8 weeks. There were no significant differences among these groups in terms of weight gain, specific growth rate, and hepatosomatic index. However, the RO groups' survival rate was significantly lower than FO groups. The feed conversion and protein efficiency ratios of RO groups were poorer than other groups. The proximate compositions of whole body and hepatopancreas were significantly affected by these dietary treatments. Tissue fatty acid composition mainly reflected dietary fatty acid compositions. Crabs fed FO diets exhibited significantly higher arachidonic, eicosapentaenoic, and docosahexaenoic acid contents in muscle and hepatopancreas compared with VO crabs. Linoleic, oleic, and linolenic acids in muscle and hepatopancreas were the highest in the SO, RO, and LO groups, respectively. The present study suggested that SO and LO could substitute for FO in fishmeal-based diets for swimming crabs, without affecting growth performance and survival.

Postsettlement growth of two estuarine crab species, Chasmagnathus granulata and Cyrtograpsus angulatus (Crustacea, Decapoda, Grapsidae): laboratory and field investigations

NASA Astrophysics Data System (ADS)

Luppi, T. A.; Spivak, E. D.; Anger, K.

2002-02-01

The estuarine grapsid crabs Chasmagnathus granulata and Cyrtograpsus angulatus belong to the most typical and dominant inhabitants of brackish coastal lagoons in southeastern South America. In a combined laboratory and field investigation of juvenile growth, we measured the increase in body size in these species under controlled conditions as well as in field experiments (in Mar Chiquita lagoon, Argentina), seasonal changes in size frequency distribution of a natural population, and growth related changes in selected morphometric traits of male and female juveniles (relations between carapace width, carapace length, propodus height and length of the cheliped, and pleon width). At 24°C, Cy. angulatus grew faster than Ch. granulata; it reached the crab-9 instar (C9; 13 mm carapace width) after 92 days, while Ch. granulata required 107 days to reach the C8 instar (7.4 mm). At 12°C, growth ceased in both species. The pleon begins to show sexual differences in the C5 ( Cy. angulatus) and C8 instar ( Ch. granulata), respectively, while the chelae differentiate earlier in Ch. granulata than in Cy. angulatus (in C4 vs C6). In the field, growth was maximal in summer, and was generally faster than in laboratory cultures. However, there is great individual variability in size (about 25% even in the first crab instar) and in size increments at ecdysis, increasing throughout juvenile growth. Our data indicate that, in the field, small-scale and short-term variations in feeding conditions, temperature, and salinity account for an extremely high degree of variability in the absolute and relative rates of growth as well as in the time to sexual differentiation.

Enhancement of the immune response and protection against Vibrio parahaemolyticus by indigenous probiotic Bacillus strains in mud crab (Scylla paramamosain).

PubMed

Wu, Hui-Juan; Sun, Ling-Bin; Li, Chuan-Biao; Li, Zhong-Zhen; Zhang, Zhao; Wen, Xiao-Bo; Hu, Zhong; Zhang, Yue-Ling; Li, Sheng-Kang

2014-12-01

In a previous study, bacterial communities of the intestine in three populations of crabs (wild crabs, pond-raised healthy crabs and diseased crabs) were probed by culture-independent methods. In this study, we examined the intestinal communities of the crabs by bacterial cultivation with a variety of media. A total of 135 bacterial strains were isolated from three populations of mud crabs. The strains were screened for antagonistic activity against Vibrio parahaemolyticus using an agar spot assay. Antagonistic strains were then identified by 16S rRNA gene sequence analysis. Three strains (Bacillus subtilis DCU, Bacillus pumilus BP, Bacillus cereus HL7) with the strongest antagonistic activity were further evaluated for their probiotic characteristics. The results showed that two (BP and DCU) of them were able to survive low pH and high bile concentrations, showed good adherence characteristics and a broad spectrum of antibiotic resistance. The probiotic effects were then tested by feeding juvenile mud crabs (Scylla paramamosain) with foods supplemented with 10(5) CFU/g of BP or DCU for 30 days before being subjected to an immersion challenge with V. parahaemolyticus for 48 h. The treated crabs showed significantly higher expression levels of immune related genes (CAT, proPO and SOD) and activities of respiratory burst than that in controlled groups. Crabs treated with BP and DCU supplemented diets exhibited survival rates of 76.67% and 78.33%, respectively, whereas survival rate was 54.88% in crabs not treated with the probiotics. The data showed that indigenous mud-associated microbiota, such as DCU and BP, have potential application in controlling pathogenic Vibriosis in mud crab aquaculture. Copyright © 2014 Elsevier Ltd. All rights reserved.

Laboratory investigations of the effects of predator sex and size on prey selection by the Asian crab, Hemigrapsus sanguineus.

PubMed

Brousseau, D J.; Filipowicz, A; Baglivo, J A.

2001-07-30

Laboratory studies have shown that the nonindigenous Asian shore crab, Hemigrapsus sanguineus, readily consumes three species of commercial bivalves: blue mussels, Mytilus edulis, soft-shell clams, Mya arenaria, and oysters, Crassostrea virginica. Although crabs can eat bivalves of a wide size range, they preferred the smaller prey (Crabs preferred M. arenaria over both M. edulis and C. virginica, and M. edulis was strongly preferred over C. virginica in pairwise comparison tests. Experiments to determine feeding rates on mussels showed that H. sanguineus can consume large numbers of mussels daily (12.7+/-11.6 mussels day(-1); sexes pooled; N=59). Mussel consumption rates increased with size of the predator and male crabs consumed more mussels than did similarly sized female crabs. The high densities of Hemigrapsus that occur in the wild, their effectiveness as predators of juvenile bivalves and their large appetites suggest an important role for these predators in restructuring the prey communities in habitats into which they have been introduced.

Laboratory trials reveal that exposure to extreme raining events prior to metamorphosis affect the post-settlement performance of an estuarine crab

NASA Astrophysics Data System (ADS)

Rey, Felisa; Silva Neto, Gina M.; Rosa, Rui; Queiroga, Henrique; Calado, Ricardo

2015-03-01

Meteorological forcing can impact planktonic communities, with extreme raining events promoting salinity decreases and triggering larval mortality in estuarine plankton. The present study evaluated how exposure to low salinities prior to metamorphosis of Carcinus maenas megalopae (last larval stage) may affect its ability to metamorphose and the post-metamorphosis performance of juvenile crabs. An extreme raining event that promoted a generalized decrease in salinity (from 25 to 10) in the whole water column of one of the main channels of a coastal lagoon was mimicked in the laboratory. Wild megalopae of C. maenas were collected and kept individually without any food at salinities of 10 or 25 (S10 or S25) until they either died or metamorphosed to the first crab instar (C1). Specimens metamorphosing in 5 days or less following their collection were labeled as early settlers (ES10 and ES25), while those taking more than 5 days were labeled as late settlers (LS10 and LS25). All newly metamorphosed crabs were kept individually until C5 at a salinity of 25 and fed ad libitum, with their intermolt periods and carapace width (CW) being recorded. Osmotic stress did not affect the survival or ability to metamorphose of C. maenas megalopae, with 89% of all larvae in both salinities being able to metamorphose. This result is supported by the ability of this larval stage to hyper-regulate. Nonetheless, an exposure of late settling megalopae to low salinities prior to metamorphosis promotes the occurrence of juvenile crabs with a smaller CW. The deleterious effects of exposing late settling megalopae to low salinities appears to be magnified during early benthic life, with C5 originating from treatment LS10 displaying a significantly smaller CW (4.87 ± 0.28 mm) and lower wet weight (WW) (28.95 ± 4.62 mg). On the other side, C5 originating from ES25 exhibited a significantly higher CW (5.90 ± 0.33 mm) and WW (50.89 ± 8.14 mg). The nutritional vulnerability experienced by

Making Kings.

PubMed

Ayoup, Colleen; Podmore, Julie

2002-01-01

Due to a general lack of representation of female masculinities within the North American media, most urban drag king cultures have evolved in isolation from each other. As a result, drag kings tend to develop locally specific codes of dress, performance styles and forms of masculinity. This chapter describes the case of a group of Montreal drag king performers, The Mambo Drag Kings (MDKs). It is based on interviews that were conducted for Colleen Ayoup's film Kings (2001), a short documentary that explores kinging by examining the development of this specific group of performers. We present excerpts from our discussions regarding the relationships between everyday gender identities, lesbian sexuality, and performing as a king in a society that is fundamentally based on an asymmetrical sex-gender system. While the chapter does highlight these theoretical concerns, the focus is on how the participants of the group interpret and experience kinging and its impact on their own gendered and sexual identities.

The Horseshoe Crab of the Genus Limulus: Living Fossil or Stabilomorph?

PubMed Central

Błażejowski, Błażej

2014-01-01

A new horseshoe crab species, Limulus darwini, is described from the uppermost Jurassic (ca. 148 Ma) near-shore sediments of the Kcynia Formation, central Poland. The only extant species Limulus polyphemus (Linnaeus) inhabits brackish-marine, shallow water environments of the east coast of the United States. Here it is shown that there are no important morphological differences between the Kcynia Formation specimens and extant juvenile representatives of the genus Limulus. The palaeoecological setting inhabited by the new species and the trophic relationships of extant horseshoe crabs are discussed in an attempt to determine the potential range of food items ingested by these Mesozoic xiphosurans. In this paper we propose the adoption of a new term stabilomorphism, this being: an effect of a specific formula of adaptative strategy among organisms whose taxonomic status does not exceed genus-level. A high effectiveness of adaptation significantly reduces the need for differentiated phenotypic variants in response to environmental changes and provides for long-term evolutionary success. PMID:25275563

Characterization and Molecular Epidemiology of a Fungal Infection of Edible Crabs (Cancer pagurus) and Interaction of the Fungus with the Dinoflagellate Parasite Hematodinium

PubMed Central

Smith, Amanda L.; Hamilton, Kristina M.; Hirschle, Lucy; Wootton, Emma C.; Vogan, Claire L.; Pope, Edward C.; Eastwood, Daniel C.

2013-01-01

This study reports on an emerging fungal disease of the edible crab, Cancer pagurus. Juvenile (prerecruit) crabs were found to be subject to this disease condition during the months of May to September at two intertidal sites in South Wales, United Kingdom. Histopathology revealed that the fungi overwhelm the host response in the tissues, leading to progressive septicemia. The causative agent of this infection was isolated and grown in pure culture and was identified as a member of the Ophiocordyceps clade by sequencing of the small subunit of the fungal ribosomal DNA (rDNA). Of the crabs naturally infected with the fungus, 94% had a coinfection with the parasitic dinoflagellate Hematodinium species. To determine if there was any interaction between the two disease-causing agents, apparently fungus-free crabs, both with and without natural Hematodinium infections, were challenged with the fungal isolate. The presence of Hematodinium caused a significant reduction in fungal multiplication in the hemocoel of the crabs in comparison to that in Hematodinium-free individuals. Histopathology of coinfected crabs showed a systemic multiplication of Hematodinium within host tissues, leading to a rapid death, while Hematodinium-free crabs experimentally infected with the fungal isolate died due to fungal sepsis (septicemia) with the same characteristic pathology as seen in natural infections. PMID:23160130

Age-specific survival estimates of King Eiders derived from satellite telemetry

USGS Publications Warehouse

Oppel, Steffen; Powell, Abby N.

2010-01-01

Age- and sex-specific survival and dispersal are important components in the dynamics and genetic structure of bird populations. For many avian taxa survival rates at the adult and juvenile life stages differ, but in long-lived species juveniles' survival is logistically challenging to study. We present the first estimates of hatch-year annual survival rates for a sea duck, the King Eider (Somateria spectabilis), estimated from satellite telemetry. From 2006 to 2008 we equipped pre-fiedging King Eiders with satellite transmitters on breeding grounds in Alaska and estimated annual survival rates during their first 2 years of life with known-fate models. We compared those estimates to survival rates of adults marked in the same area from 2002 to 2008. Hatch-year survival varied by season during the first year of life, and model-averaged annual survival rate was 0.67 (95% CI: 0.48–0.80). We did not record any mortality during the second year and were therefore unable to estimate second-year survival rate. Adults' survival rate was constant through the year (0.94, 95% CI: 0.86–0.97). No birds appeared to breed during their second summer. While 88% of females with an active transmitter (n = 9) returned to their natal area at the age of 2 years, none of the 2-year old males (n = 3) did. This pattern indicates that females' natal philopatry is high and suggests that males' higher rates of dispersal may account for sex-specific differences in apparent survival rates of juvenile sea ducks when estimated with mark—recapture methods.

Microhabitat selection, demography, and correlates of home range size for the King Rail (Rallus elegans)

USGS Publications Warehouse

Pickens, Bradley A.; King, Sammy L.

2013-01-01

Animal movements and habitat selection within the home range, or microhabitat selection, can provide insights into habitat requirements, such as foraging and area requirements. The King Rail (Rallus elegans) is a wetland bird of high conservation concern in the United States, but little is known about its movements, habitats, or demography. King Rails (n = 34) were captured during the 2010–2011 breeding seasons in the coastal marshes of southwest Louisiana and southeast Texas. Radio telemetry and direct habitat surveys of King Rail locations were conducted to estimate home ranges and microhabitat selection. Within home ranges, King Rails selected for greater plant species richness and comparatively greater coverage of Phragmites australis, Typha spp., and Schoenoplectus robustus. King Rails were found closer to open water compared to random locations placed 50 m from King Rail locations. Home ranges (n = 22) varied from 0.8–32.8 ha and differed greatly among sites. Home range size did not vary by year or sex; however, increased open water, with a maximum of 29% observed in the study, was correlated with smaller home ranges. Breeding season cumulative survivorship was 89% ± 22% in 2010 and 61% ± 43% in 2011, which coincided with a drought. With an equal search effort, King Rail chicks and juveniles observed in May-June decreased from 110 in 2010 to only 16 in the drier year of 2011. The findings show King Rail used marsh with ≤ 29% open water and had smaller home ranges when open water was more abundant.

Isolation, gene cloning and expression profile of a pathogen recognition protein: a serine proteinase homolog (Sp-SPH) involved in the antibacterial response in the crab Scylla paramamosain.

PubMed

Liu, Hai-peng; Chen, Rong-yuan; Zhang, Min; Wang, Ke-jian

2010-07-01

To identify the frontline defense molecules against microbial infection in the crab Scylla paramamosain, a live crab pathogenic microbe, Vibrio parahaemolyticus, was recruited as an affinity matrix to isolate innate immune factors from crab hemocytes lysate. Interestingly, a serine proteinase homolog (Sp-SPH) was obtained together with an antimicrobial peptide-antilipopolysaccharide factor (Sp-ALF). We then determined the full-length cDNA sequence of Sp-SPH, which contained 1298bp with an open reading frame of 1107bp encoding 369 amino acid residues. Multiple alignment analysis showed that the deduced amino acid sequences of Sp-SPH shared overall identity (83.8%) with those of SPH-containing proteins from other crab species. Tissue distribution analysis indicated that the Sp-SPH transcripts were present in various tissues including eye stalk, subcuticular epidermis, gill, hemocyte, stomach, thorax ganglion, brain and muscle of S. paramamosain. The Sp-SPH was highly expressed in selected different development stages including embryo (I, II, III and V), zoea (I), megalopa, and juvenile. Importantly, the prophenoloxidase was also present in the embryos, zoea, juvenile and adult crabs, but relatively lower in megalopa compared to those of other stages. Furthermore, the Sp-SPH mRNA expression showed a statistically significant increase (P<0.05) in both hemocyte and subcuticular epidermis at 24h, and in gill at 96h after challenge of V. parahaemolyticus determined by quantitative real-time PCR. Taken together, the live-bacterial-binding activity and the acute-phase response against bacterial infection of Sp-SPH suggested that it might function as an innate immune recognition molecule and play a key role in host defense against microbe invasion in the crab S. paramamosain. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Entrainment of Dungeness Crab in the Desdemona Shoals Reach of the Lower Columbia River Navigation Channel

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

Pearson, Walter H.; Kohn, Nancy P.; Skalski, J. R.

2006-09-30

Proposed dredging of the Columbia River has raised concerns about related impacts on Dungeness crab in the Columbia River Estuary (CRE). This study follows two major efforts, sponsored by the Portland District of the U. S. Army Corps of Engineers (USACE) to quantify the number of crabs entrained by a hopper dredge working in the CRE. From June 2002 through September 2002, Pacific Northwest National Laboratory (PNNL) conducted direct measurements of crab entrainment in the CRE from the mouth of the Columbia River (MCR, river mile -3 to +3) upriver as far as Miller Sands (river mile 21 to 24).more » These studies constituted a major step in quantifying crab entrainment in the CRE, and allowed statistically bounded projections of adult equivalent loss (AEL) for Dungeness crab populations under a range of future construction dredging and maintenance dredging scenarios (Pearson et al. 2002, 2003). In 2004, PNNL performed additional measurements to improve estimates of crab entrainment at Desdemona Shoals and at Flavel Bar, a reach near Astoria that had not been adequately sampled in 2002 (Figure 1). The 2004 data were used to update the crab loss projections for channel construction to 43 ft MLLW. In addition, a correlation between bottom salinity and adult (age 2+ and 3+, >100 mm carapace width) crab entrainment was developed using 2002 data, and elaborated upon with the 2004 data. This crab salinity model was applied to forecasting seasonal (monthly) entrainment rates and AEL using seasonal variations in salinity (Pearson et al. 2005). In the previous studies, entrainment rates in Desdemona Shoals were more variable than in any of the other reaches. Pearson et al. (2005) concluded that ?the dynamics behind the variable entrainment rates at Desdemona Shoals are not fully understood,? as well as finding that juvenile crab entrainment was not significantly correlated with salinity as it was for older crab. The present study was undertaken to address the question of

Larval development of the subantarctic king crabs Lithodes santolla and Paralomis granulosa reared in the laboratory

NASA Astrophysics Data System (ADS)

Calcagno, J. A.; Anger, K.; Lovrich, G. A.; Thatje, S.; Kaffenberger, A.

2004-02-01

The larval development and survival in the two subantarctic lithodid crabs Lithodes santolla (Jaquinot) and Paralomis granulosa (Molina) from the Argentine Beagle Channel were studied in laboratory cultures. In L. santolla, larval development lasted about 70 days, passing through three zoeal stages and the megalopa stage, with a duration of approximately 4, 7, 11 and 48 days, respectively. The larval development in P. granulosa is more abbreviated, comprising only two zoeal stages and the megalopa stage, with 6, 11 and 43 days' duration, respectively. In both species, we tested for effects of presence versus absence of food (Artemia nauplii) on larval development duration and survival rate. In P. granulosa, we also studied effects of different rearing conditions, such as individual versus mass cultures, as well as aerated versus unaerated cultures. No differences in larval development duration and survival were observed between animals subjected to those different rearing conditions. The lack of response to the presence or absence of potential food confirms, in both species, a complete lecithotrophic mode of larval development. Since lithodid crabs are of high economic importance in the artisanal fishery in the southernmost parts of South America, the knowledge of optimal rearing conditions for lithodid larvae is essential for future attempts at repopulating the collapsing natural stocks off Tierra del Fuego.

Positive feedback fishery: Population consequences of `crab-tiling' on the green crab Carcinus maenas

NASA Astrophysics Data System (ADS)

Sheehan, E. V.; Thompson, R. C.; Coleman, R. A.; Attrill, M. J.

2008-11-01

Collection of marine invertebrates for use as fishing bait is a substantial activity in many parts of the world, often with unknown ecological consequences. As new fisheries develop, it is critical for environmental managers to have high quality ecological information regarding the potential impacts, in order to develop sound management strategies. Crab-tiling is a largely unregulated and un-researched fishery, which operates commercially in the south-west UK. The target species is the green crab Carcinus maenas. Those crabs which are pre-ecdysis and have a carapace width greater than 40 mm are collected to be sold to recreational anglers as bait. Collection involves laying artificial structures on intertidal sandflats and mudflats in estuaries. Crabs use these structures as refugia and are collected during low tide. However, the effect that this fishery has on populations of C. maenas is not known. The impact of crab-tiling on C. maenas population structure was determined by sampling crabs from tiled estuaries and non-tiled estuaries using baited drop-nets. A spatially and temporarily replicated, balanced design was used to compare crab abundance, sizes and sex ratios between estuaries. Typically, fisheries are associated with a reduction in the abundance of the target species. Crab-tiling, however, significantly increased C. maenas abundance. This was thought to be a result of the extra habitat in tiled estuaries, which probably provides protection from natural predators, such as birds and fish. Although crabs were more abundant in tiled estuaries than non-tiled estuaries, the overall percentage of reproductively active crabs in non-tiled estuaries was greater than in tiled estuaries. As with most exploited fisheries stocks, crabs in exploited (tiled) estuaries tended to be smaller, with a modal carapace width of 20-29 mm rather than 30-39 mm in non-tiled estuaries. The sex ratio of crabs however; was not significantly different between tiled and non

American Horshoe Crab (Limulus polyphemus) : Population Ecology within the Northern Gulf of Mexico

NASA Astrophysics Data System (ADS)

Carter, S. C.; Carmichael, R. H.; Estes, M. G., Jr.; McBarnes, M.

2016-02-01

To better understand the occurrence and population structure of horseshoe crabs in the northern Gulf of Mexico, we sampled animals on Petit Bois Island, Dauphin Island, and Fort Morgan. To determine if major life history events such as spawning, molting, or mortality occurred more frequently at certain locations and times, we counted molts, live animals (noted whether animals were alone or amplexed for spawning), and carcasses. We also tested the hypothesis that demographics of molts or carcasses found on local beaches represent nearby live animal populations by tracking the redistribution of tagged molts placed at variable distances from shore (2, 50, 100 m). Overall, our data suggested a greater occurrence of spawning adults and actively molting juveniles on Petit Bois Island compared to other sites. The number of specimens found at Dauphin Island and Fort Morgan declined since 2012, possibly due to a regional-scale change in environmental conditions. Size frequency distributions of molts and carcasses collected during 2015 were similar to values from previous studies, but showed a higher number of subadult horseshoe crab carcasses in 2015 compared to other years. Tagged molts were recovered at a rate of 2.5%, suggesting that few molts deposited in nearby waters make it to local beaches. Tagged molts were recovered at 1 - 22 days following field placement, with the majority of recovered molts found after 1 day. Because smaller crabs (<40 mm size) stay close to natal beaches when molting, their molts are most likely to wash ashore. Data provided by this study will help inform future research on horseshoe crab ecology and assess how natural and anthropogenic perturbaRons may affect horseshoe crab populaRons in the northern Gulf of Mexico.

Territoriality and Conflict Avoidance Explain Asociality (Solitariness) of the Endosymbiotic Pea Crab Tunicotheres moseri

PubMed Central

Ambrosio, Louis J.; Baeza, J. Antonio

2016-01-01

Host monopolization theory predicts symbiotic organisms inhabiting morphologically simple, relatively small and scarce hosts to live solitarily as a result of territorial behaviors. We tested this prediction with Tunicotheres moseri, an endosymbiotic crab dwelling in the atrial chamber of the morphologically simple, small, and relatively scarce ascidian Styela plicata. As predicted, natural populations of T. moseri inhabit ascidian hosts solitarily with greater frequency than expected by chance alone. Furthermore, laboratory experiments demonstrated that intruder crabs take significantly longer to colonize previously infected compared to uninfected hosts, indicating as expected, that resident crabs exhibit monopolization behaviors. While territoriality does occur, agonistic behaviors employed by T. moseri do not mirror the overt behaviors commonly reported for other territorial crustaceans. Documented double and triple cohabitations in the field coupled with laboratory observations demonstrating the almost invariable success of intruder crabs colonizing occupied hosts, suggest that territoriality is ineffective in completely explaining the solitary social habit of this species. Additional experiments showed that T. moseri juveniles and adults, when searching for ascidians use chemical cues to avoid hosts occupied by conspecifics. This conspecific avoidance behavior reported herein is a novel strategy most likely employed to preemptively resolve costly territorial conflicts. In general, this study supports predictions central to host monopolization theory, but also implies that alternative behavioral strategies (i.e., conflict avoidance) may be more important than originally thought in explaining the host use pattern of symbiotic organisms. PMID:26910474

Territoriality and Conflict Avoidance Explain Asociality (Solitariness) of the Endosymbiotic Pea Crab Tunicotheres moseri.

PubMed

Ambrosio, Louis J; Baeza, J Antonio

2016-01-01

Host monopolization theory predicts symbiotic organisms inhabiting morphologically simple, relatively small and scarce hosts to live solitarily as a result of territorial behaviors. We tested this prediction with Tunicotheres moseri, an endosymbiotic crab dwelling in the atrial chamber of the morphologically simple, small, and relatively scarce ascidian Styela plicata. As predicted, natural populations of T. moseri inhabit ascidian hosts solitarily with greater frequency than expected by chance alone. Furthermore, laboratory experiments demonstrated that intruder crabs take significantly longer to colonize previously infected compared to uninfected hosts, indicating as expected, that resident crabs exhibit monopolization behaviors. While territoriality does occur, agonistic behaviors employed by T. moseri do not mirror the overt behaviors commonly reported for other territorial crustaceans. Documented double and triple cohabitations in the field coupled with laboratory observations demonstrating the almost invariable success of intruder crabs colonizing occupied hosts, suggest that territoriality is ineffective in completely explaining the solitary social habit of this species. Additional experiments showed that T. moseri juveniles and adults, when searching for ascidians use chemical cues to avoid hosts occupied by conspecifics. This conspecific avoidance behavior reported herein is a novel strategy most likely employed to preemptively resolve costly territorial conflicts. In general, this study supports predictions central to host monopolization theory, but also implies that alternative behavioral strategies (i.e., conflict avoidance) may be more important than originally thought in explaining the host use pattern of symbiotic organisms.

What regulates crab predation on mangrove propagules?

NASA Astrophysics Data System (ADS)

Van Nedervelde, Fleur; Cannicci, Stefano; Koedam, Nico; Bosire, Jared; Dahdouh-Guebas, Farid

2015-02-01

Crabs play a major role in some ecosystems. To increase our knowledge about the factors that influence crab predation on propagules in mangrove forests, we performed experiments in Gazi Bay, Kenya in July 2009. We tested whether: (1) crab density influences propagule predation rate; (2) crab size influences food competition and predation rate; (3) crabs depredate at different rates according to propagule and canopy cover species; (4) vegetation density is correlated with crab density; (5) food preferences of herbivorous crabs are determined by size, shape and nutritional value. We found that (1) propagule predation rate was positively correlated to crab density. (2) Crab competitive abilities were unrelated to their size. (3) Avicennia marina propagules were consumed more quickly than Ceriops tagal except under C. tagal canopies. (4) Crab density was negatively correlated with the density of A. marina trees and pneumatophores. (5) Crabs prefer small items with a lower C:N ratio. Vegetation density influences crab density, and crab density affects propagule availability and hence vegetation recruitment rate. Consequently, the mutual relationships between vegetation and crab populations could be important for forest restoration success and management.

Post-Fledging Dispersal of King Penguins (Aptenodytes patagonicus) from Two Breeding Sites in the South Atlantic

PubMed Central

Pütz, Klemens; Trathan, Phil N.; Pedrana, Julieta; Collins, Martin A.; Poncet, Sally; Lüthi, Benno

2014-01-01

Most studies concerning the foraging ecology of marine vertebrates are limited to breeding adults, although other life history stages might comprise half the total population. For penguins, little is known about juvenile dispersal, a period when individuals may be susceptible to increased mortality given their naïve foraging behaviour. Therefore, we used satellite telemetry to study king penguin fledglings (n = 18) from two sites in the Southwest Atlantic in December 2007. The two sites differed with respect to climate and proximity to the Antarctic Polar Front (APF), a key oceanographic feature generally thought to be important for king penguin foraging success. Accordingly, birds from both sites foraged predominantly in the vicinity of the APF. Eight king penguins were tracked for periods greater than 120 days; seven of these (three from the Falkland Islands and four from South Georgia) migrated into the Pacific. Only one bird from the Falkland Islands moved into the Indian Ocean, visiting the northern limit of the winter pack-ice. Three others from the Falkland Islands migrated to the eastern coast of Tierra del Fuego before travelling south. Derived tracking parameters describing their migratory behaviour showed no significant differences between sites. Nevertheless, generalized linear habitat modelling revealed that juveniles from the Falkland Islands spent more time in comparatively shallow waters with low sea surface temperature, sea surface height and chlorophyll variability. Birds from South Georgia spent more time in deeper waters with low sea surface temperature and sea surface height, but high concentrations of chlorophyll. Our results indicate that inexperienced king penguins, irrespective of the location of their natal site in relation to the position of the APF, develop their foraging skills progressively over time, including specific adaptations to the environment around their prospective breeding site. PMID:24828545

Post-fledging dispersal of king penguins (Aptenodytes patagonicus) from two breeding sites in the South Atlantic.

PubMed

Pütz, Klemens; Trathan, Phil N; Pedrana, Julieta; Collins, Martin A; Poncet, Sally; Lüthi, Benno

2014-01-01

Most studies concerning the foraging ecology of marine vertebrates are limited to breeding adults, although other life history stages might comprise half the total population. For penguins, little is known about juvenile dispersal, a period when individuals may be susceptible to increased mortality given their naïve foraging behaviour. Therefore, we used satellite telemetry to study king penguin fledglings (n = 18) from two sites in the Southwest Atlantic in December 2007. The two sites differed with respect to climate and proximity to the Antarctic Polar Front (APF), a key oceanographic feature generally thought to be important for king penguin foraging success. Accordingly, birds from both sites foraged predominantly in the vicinity of the APF. Eight king penguins were tracked for periods greater than 120 days; seven of these (three from the Falkland Islands and four from South Georgia) migrated into the Pacific. Only one bird from the Falkland Islands moved into the Indian Ocean, visiting the northern limit of the winter pack-ice. Three others from the Falkland Islands migrated to the eastern coast of Tierra del Fuego before travelling south. Derived tracking parameters describing their migratory behaviour showed no significant differences between sites. Nevertheless, generalized linear habitat modelling revealed that juveniles from the Falkland Islands spent more time in comparatively shallow waters with low sea surface temperature, sea surface height and chlorophyll variability. Birds from South Georgia spent more time in deeper waters with low sea surface temperature and sea surface height, but high concentrations of chlorophyll. Our results indicate that inexperienced king penguins, irrespective of the location of their natal site in relation to the position of the APF, develop their foraging skills progressively over time, including specific adaptations to the environment around their prospective breeding site.

Convolutional neural network guided blue crab knuckle detection for autonomous crab meat picking machine

NASA Astrophysics Data System (ADS)

Wang, Dongyi; Vinson, Robert; Holmes, Maxwell; Seibel, Gary; Tao, Yang

2018-04-01

The Atlantic blue crab is among the highest-valued seafood found in the American Eastern Seaboard. Currently, the crab processing industry is highly dependent on manual labor. However, there is great potential for vision-guided intelligent machines to automate the meat picking process. Studies show that the back-fin knuckles are robust features containing information about a crab's size, orientation, and the position of the crab's meat compartments. Our studies also make it clear that detecting the knuckles reliably in images is challenging due to the knuckle's small size, anomalous shape, and similarity to joints in the legs and claws. An accurate and reliable computer vision algorithm was proposed to detect the crab's back-fin knuckles in digital images. Convolutional neural networks (CNNs) can localize rough knuckle positions with 97.67% accuracy, transforming a global detection problem into a local detection problem. Compared to the rough localization based on human experience or other machine learning classification methods, the CNN shows the best localization results. In the rough knuckle position, a k-means clustering method is able to further extract the exact knuckle positions based on the back-fin knuckle color features. The exact knuckle position can help us to generate a crab cutline in XY plane using a template matching method. This is a pioneering research project in crab image analysis and offers advanced machine intelligence for automated crab processing.

36 CFR 242.28 - Subsistence taking of shellfish.

Code of Federal Regulations, 2012 CFR

2012-07-01

... management jurisdiction, except the marine waters occurring in the vicinity of Makhnati Island as described... of king crab: (A) The annual limit is three crabs per household; only male king crab with shell width..., Gibson Cove, and an area defined by a line 1/2 mile on either side of the mouth of the Karluk River, and...

36 CFR 242.28 - Subsistence taking of shellfish.

Code of Federal Regulations, 2011 CFR

2011-07-01

... management jurisdiction, except the marine waters occurring in the vicinity of Makhnati Island as described... of king crab: (A) The annual limit is three crabs per household; only male king crab with shell width..., Gibson Cove, and an area defined by a line 1/2 mile on either side of the mouth of the Karluk River, and...

36 CFR 242.28 - Subsistence taking of shellfish.

Code of Federal Regulations, 2014 CFR

2014-07-01

... management jurisdiction, except the marine waters occurring in the vicinity of Makhnati Island as described... of king crab: (A) The annual limit is three crabs per household; only male king crab with shell width..., Gibson Cove, and an area defined by a line 1/2 mile on either side of the mouth of the Karluk River, and...

36 CFR 242.28 - Subsistence taking of shellfish.

Code of Federal Regulations, 2013 CFR

2013-07-01

... management jurisdiction, except the marine waters occurring in the vicinity of Makhnati Island as described... of king crab: (A) The annual limit is three crabs per household; only male king crab with shell width..., Gibson Cove, and an area defined by a line 1/2 mile on either side of the mouth of the Karluk River, and...

78 FR 8110 - North Pacific Fishery Management Council; Public Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-05

... will be held at the Hilton Hotel, Birch/Willow room, 500 West 3rd Avenue, Anchorage, AK. Council... assessment models for Aleutian Islands golden king crab and Norton Sound red king crab. The Agenda is subject...

Infestation of an introduced host, the European green crab, Carcinus maenas, by a symbiotic nemertean egg predator, Carcinonemertes epialti.

PubMed

Torchin, M E; Lafferty, K D; Kuris, A M

1996-06-01

The recent introduction of the European green crab, Carcinus maenas, to the west coast of the U.S. has provided an opportunity for host transfer of the symbiotic nemertean egg predator, Carcinonemertes epialti, from its native shore crab host, Hemigrapsus oregonensis to the exotic C. maenas. Two surveys of C. maenas in Bodega Harbor, California, revealed that, in March 1995 prevalence of C. epialti on C. maenas was significantly lower than on H. oregonensis (11% versus 74%), but in November 1995 there was no significant difference between the 2 species (79% versus 98%). Only juvenile C. epialti were recovered from C. maenas in March 1995. However, in November 1995, ovigerous C. maenas were harboring actively feeding adult worms. Prevalence in both crab species significantly differed from March to November. Laboratory studies revealed that C. epialti fed and reproduced on eggs of C. maenas. The feeding rate of C. epialti on C. maenas eggs (2.5 eggs/trial) was not significantly different from that on H. oregonensis eggs (3.6 eggs/trial). Our findings suggest that this nemertean may have less host specificity than was previously thought. If C. epialti causes brood mortality of C. maenas in nature, it could potentially impact populations of this exotic crab.

50 CFR 253.30 - Crab IFQ loans.

Code of Federal Regulations, 2012 CFR

2012-10-01

...: (1) Crab means those crab species managed under the Fishery Management Plan for Bering Sea/Aleutian... eligibility requirements to fish for crab or hold Crab QS contained in the Crab FMP implementing regulations... of any person determined by RAM to be unable to receive such certification will be declined...

50 CFR 253.30 - Crab IFQ loans.

Code of Federal Regulations, 2011 CFR

2011-10-01

...: (1) Crab means those crab species managed under the Fishery Management Plan for Bering Sea/Aleutian... eligibility requirements to fish for crab or hold Crab QS contained in the Crab FMP implementing regulations... of any person determined by RAM to be unable to receive such certification will be declined...

50 CFR 253.30 - Crab IFQ loans.

Code of Federal Regulations, 2013 CFR

2013-10-01

...: (1) Crab means those crab species managed under the Fishery Management Plan for Bering Sea/Aleutian... eligibility requirements to fish for crab or hold Crab QS contained in the Crab FMP implementing regulations... of any person determined by RAM to be unable to receive such certification will be declined...

50 CFR 253.30 - Crab IFQ loans.

Code of Federal Regulations, 2014 CFR

2014-10-01

...: (1) Crab means those crab species managed under the Fishery Management Plan for Bering Sea/Aleutian... eligibility requirements to fish for crab or hold Crab QS contained in the Crab FMP implementing regulations... of any person determined by RAM to be unable to receive such certification will be declined...

Intrusion of Subarctic Currents into a Perpetual Sub-zero Cold Pool Allows Recruitment and Export of Snow Crabs in the Northern Bering Sea

NASA Astrophysics Data System (ADS)

Kolts, J. M.; Lovvorn, J. R.; North, C. A.; Janout, M. A.

2016-02-01

Snow crabs (Chionoecetes opilio) are quite productive at suitable temperatures, but can also be abundant in water cold enough to depress settlement of larvae, growth, and reproduction. In much of the northern Bering Sea, bottom water temperatures are <-1°C for most or all of the year. Crab pelagic larvae prefer to settle at temperatures >0°C, so we found high densities of juveniles only where intruding warm currents deposited larvae in localized areas. After settlement, maturing crabs appeared to exhibit ontogenetic migration toward deeper, warmer water. Cold temperatures excluded key predators, but decreased fecundity by restricting females to small body size (with associated small clutches) and to breeding every 2 years. Migration to warmer water may allow females to breed annually, and to encounter more adult males needed to fertilize subsequent clutches. Because older males also emigrate, remaining adolescent males probably inseminate newly maturing females. Without localized intrusion of warmer currents, snow crabs might not persist at high densities in such cold waters. However, they are currently very abundant there, and export many pelagic larvae and adults. In this region of Arctic temperatures, the combination of localized intrusion of warm, Subarctic currents and ontogenetic migration toward warmer Subarctic waters allows this area to contribute importantly to adult crab populations in adjacent areas.

Transcriptome analysis of mud crab (Scylla paramamosain) gills in response to Mud crab reovirus (MCRV).

PubMed

Liu, Shanshan; Chen, Guanxing; Xu, Haidong; Zou, Weibin; Yan, Wenrui; Wang, Qianqian; Deng, Hengwei; Zhang, Heqian; Yu, Guojiao; He, Jianguo; Weng, Shaoping

2017-01-01

Mud crab (Scylla paramamosain) is an economically important marine cultured species in China's coastal area. Mud crab reovirus (MCRV) is the most important pathogen of mud crab, resulting in large economic losses in crab farming. In this paper, next-generation sequencing technology and bioinformatics analysis are used to study transcriptome differences between MCRV-infected mud crab and normal control. A total of 104.3 million clean reads were obtained, including 52.7 million and 51.6 million clean reads from MCRV-infected (CA) and controlled (HA) mud crabs respectively. 81,901, 70,059 and 67,279 unigenes were gained respectively from HA reads, CA reads and HA&CA reads. A total of 32,547 unigenes from HA&CA reads called All-Unigenes were matched to at least one database among Nr, Nt, Swiss-prot, COG, GO and KEGG databases. Among these, 13,039, 20,260 and 11,866 unigenes belonged to the 3, 258 and 25 categories of GO, KEGG pathway, and COG databases, respectively. Solexa/Illumina's DGE platform was also used, and about 13,856 differentially expressed genes (DEGs), including 4444 significantly upregulated and 9412 downregulated DEGs were detected in diseased crabs compared with the control. KEGG pathway analysis revealed that DEGs were obviously enriched in the pathways related to different diseases or infections. This transcriptome analysis provided valuable information on gene functions associated with the response to MCRV in mud crab, as well as detail information for identifying novel genes in the absence of the mud crab genome database. Copyright © 2016. Published by Elsevier Ltd.

Plasma thyroid hormone pattern in king penguin chicks: a semi-altricial bird with an extended posthatching developmental period.

PubMed

Cherel, Yves; Durant, Joël M; Lacroix, André

2004-05-01

Plasma concentrations of thyroid hormones (TH) were investigated during the extended posthatching developmental period (approximately 11 months) of a semi-altricial bird species, the king penguin (Aptenodytes patagonicus). The first period of growth in summer was marked by a progressive rise in plasma T4 concentration that paralleled rapid increases in body mass and in structural and down growth. By contrast, plasma T3 concentration had already reached adult levels in newly hatched chicks and did not change thereafter. Circulating TH of king penguin chicks thus follow an original pattern when comparing to altricial and precocial species. During the austral winter, the long period of undernutrition of king penguin chicks was characterized by a decrease in circulating TH that can be related to a seasonal stop in growth and energy saving mechanisms. Plasma TH concentrations increased again during the second growth phase in spring, and they reached their highest levels at the end of the fledging period, slightly before juveniles initiated their first foraging trip at sea. As expected, plasma T4 levels were elevated when chicks moulted, developing a true-adult type waterproof plumage. The data also suggest that T4 plays a major role in skeletal development and pectoral muscle maturation in anticipation of marine life. Plasma T3 was at its highest during the period when juveniles improved resistance to cold waters by going back and forth to the sea, suggesting a role for circulating T3 in cold acclimatization occurring at that time.

Prevalence, characterization and sources of Listeria monocytogenes in blue crab (Callinectus sapidus) meat and blue crab processing plants.

PubMed

Pagadala, Sivaranjani; Parveen, Salina; Rippen, Thomas; Luchansky, John B; Call, Jeffrey E; Tamplin, Mark L; Porto-Fett, Anna C S

2012-09-01

Seven blue crab processing plants were sampled to determine the prevalence and sources of Listeria spp. and Listeria monocytogenes for two years (2006-2007). A total of 488 raw crabs, 624 cooked crab meat (crab meat) and 624 environmental samples were tested by standard methods. Presumptive Listeria spp. were isolated from 19.5% of raw crabs, 10.8% of crab meat, and 69.5% of environmental samples. L. monocytogenes was isolated from 4.5% of raw crabs, 0.2% of crab meat, and 2.1% of environmental samples. Ninety-seven percent of the isolates were resistant to at least one of the ten antibiotics tested. Eight different serotypes were found among 76 L. monocytogenes isolates tested with the most common being 4b, 1/2b and 1/2a. Automated EcoRI ribotyping differentiated 11 ribotypes among the 106 L. monocytogenes isolates. Based on ribotyping analysis, the distribution of the ribotypes in each processing plant had a unique contamination pattern. A total of 92 ApaI and 88 AscI pulsotypes among the 106 L. monocytogenes isolates were found and distinct pulsotypes were observed in raw crab, crab meat and environmental samples. Ribotypes and serotypes recovered from crab processing plants included subtypes that have been associated with listeriosis cases in other food outbreaks. Our findings suggest that molecular methods may provide critical information about sources of L. monocytogenes in crab processing plants and will augment efforts to improve food safety control strategies such as targeting specific sources of contamination and use of aggressive detergents prior to sanitizing. Copyright © 2012 Elsevier Ltd. All rights reserved.

LIFE CYCLE, DISTRIBUTION AND ABUNDANCE OF CARCINONEMERTES EPIALTI, A NEMERTEAN EGG PREDATOR OF THE SHORE CRAB, HEMIGRAPSUS OREGONENSIS, IN RELATION TO HOST SIZE, REPRODUCTION AND MOLT CYCLE.

PubMed

Kuris, Armand M

1978-02-01

1. The geographic range of Carcinonemertes epialti has been greatly extended. The worms are found from Bahia San Quintin, Baja California, Mexico, to Page's Lagoon, Vancouver Island, British Columbia, Canada. 2. New host records for C. epialti include H. oregonensis, and H. nudus. It is rare on its type host Pugettia producta. Specimens of Carcinonemertes of uncertain affinities are also found on Cancer antennarius, C. anthonyi and C. productus. 3. Carcinonemertes epialti adults are egg predators on ovigerous hosts. Growth, demography and abundance are described in relation to the embryogenic stage of the host brood at Bodega Harbor, California. 4. Nonfeeding juveniles are ensheathed on individuals of both host sexes over 8.0 mm carapace width. 5. Transmission experiments show that contact transfer of juvenile nemerteans from males to other hosts may occur. 6. The percentage of infestation and mean density peak in autumn on H. oregonensis at Bodega Harbor. 7. Ovigerous female hosts are more frequently infested with C. epialti, particularly at small host sizes, than are male or nonovigerous female hosts at Bodega Harbor. However, average worm density on ovigerous females is low. 8. Mean density of C. epialti rises through late postmolt, declines during intermolt and rebuilds to a high level in late premolt H. oregonensisfrom Bodega Harbor. 9. Large crabs have a higher percentage of infestations and mean densities per infection than do small crabs. Nemerteans are more frequently found in the sternal-abdominal furrow and less frequently in the limb axillae on large crabs. 10. A model of C. epialti transmission and site occupancy is proposed, incorporating the influence of host size, sex, reproductive state, embryogenesis, molt cycle stage and molt cycle duration of H. oregonensis at Bodega Harbor. Site availability increases with host size. At higher densities the juvenile nemerteans increasingly occupy less preferred sites. Transferral of juvenile nemerteans occurs

Comparative analysis of the proximate and elemental composition of the blue crab Callinectes sapidus, the warty crab Eriphia verrucosa, and the edible crab Cancer pagurus.

PubMed

Zotti, Maurizio; Coco, Laura Del; Pascali, Sandra Angelica De; Migoni, Danilo; Vizzini, Salvatrice; Mancinelli, Giorgio; Fanizzi, Francesco Paolo

2016-02-01

The proximate composition and element contents of claw muscle tissue of Atlantic blue crabs (Callinectes sapidus) were compared with the native warty crab (Eriphia verrucosa) and the commercially edible crab (Cancer pagurus). The scope of the analysis was to profile the chemical characteristics and nutritive value of the three crab species. Elemental fingerprints showed significant inter-specific differences, whereas non-significant variations in the moisture and ash contents were observed. In the blue crab, protein content was significantly lower than in the other two species, while its carbon content resulted lower than that characterizing only the warty crab. Among micro-elements, Ba, Cr, Cu, Li, Mn, Ni, and Pb showed extremely low concentrations and negligible among-species differences. Significant inter-specific differences were observed for Na, Sr, V, Ba, Cd and Zn; in particular, cadmium and zinc were characterized in the blue crab by concentrations significantly lower than in the other two species. The analysis of the available literature on the three species indicated a general lack of comparable information on their elemental composition. The need to implement extended elemental fingerprinting techniques for shellfish quality assessment is discussed, in view of other complementary profiling methods such as NMR-based metabolomics.

Perceptions of environmental changes and lethargic crab disease among crab harvesters in a Brazilian coastal community.

PubMed

Firmo, Angélica M S; Tognella, Mônica M P; Có, Walter L O; Barboza, Raynner R D; Alves, Rômulo R N

2011-11-16

Lethargic Crab Disease (LCD) has caused significant mortalities in the population of Ucides cordatus crabs in the Mucuri estuary in Bahia State, Brazil, and has brought social and economic problems to many crab-harvesting communities that depend on this natural resource. The present work examined the perceptions of members of a Brazilian crab harvesting community concerning environmental changes and the Lethargic Crab Disease. Field work was undertaken during the period between January and April/2009, with weekly or biweekly field excursions during which open and semi-structured interviews were held with local residents in the municipality of Mucuri, Bahia State, Brazil. A total of 23 individuals were interviewed, all of whom had at least 20 years of crab-collecting experience in the study region. Key-informants (more experienced crab harvesters) were selected among the interviewees using the "native specialist" criterion. According to the collectors, LCD reached the Mucuri mangroves between 2004 and 2005, decimating almost all crab population in the area, and in 2007, 2008 and 2009 high mortalities of U. cordatus were again observed as a result of recurrences of this disease in the region. In addition to LCD, crabs were also suffering great stock reductions due to habitat degradation caused by deforestation, landfills, sewage effluents, domestic and industrial wastes and the introduction of exotic fish in the Mucuri River estuary. The harvesting community was found to have significant ecological knowledge about the functioning of mangrove swamp ecology, the biology of crabs, and the mass mortality that directly affected the economy of this community, and this information was largely in accordance with scientific knowledge. The study of traditional knowledge makes it possible to better understand human interactions with the environment and aids in the elaboration of appropriate strategies for natural resource conservation.

Perceptions of environmental changes and Lethargic crab disease among crab harvesters in a Brazilian coastal community

PubMed Central

2011-01-01

Background Lethargic Crab Disease (LCD) has caused significant mortalities in the population of Ucides cordatus crabs in the Mucuri estuary in Bahia State, Brazil, and has brought social and economic problems to many crab-harvesting communities that depend on this natural resource. The present work examined the perceptions of members of a Brazilian crab harvesting community concerning environmental changes and the Lethargic Crab Disease. Methods Field work was undertaken during the period between January and April/2009, with weekly or biweekly field excursions during which open and semi-structured interviews were held with local residents in the municipality of Mucuri, Bahia State, Brazil. A total of 23 individuals were interviewed, all of whom had at least 20 years of crab-collecting experience in the study region. Key-informants (more experienced crab harvesters) were selected among the interviewees using the "native specialist" criterion. Results According to the collectors, LCD reached the Mucuri mangroves between 2004 and 2005, decimating almost all crab population in the area, and in 2007, 2008 and 2009 high mortalities of U. cordatus were again observed as a result of recurrences of this disease in the region. In addition to LCD, crabs were also suffering great stock reductions due to habitat degradation caused by deforestation, landfills, sewage effluents, domestic and industrial wastes and the introduction of exotic fish in the Mucuri River estuary. The harvesting community was found to have significant ecological knowledge about the functioning of mangrove swamp ecology, the biology of crabs, and the mass mortality that directly affected the economy of this community, and this information was largely in accordance with scientific knowledge. Conclusions The study of traditional knowledge makes it possible to better understand human interactions with the environment and aids in the elaboration of appropriate strategies for natural resource conservation

Dietary nano-selenium relieves hypoxia stress and, improves immunity and disease resistance in the Chinese mitten crab (Eriocheir sinensis).

PubMed

Qin, Fenju; Shi, Miaomiao; Yuan, Hongxia; Yuan, Linxi; Lu, Wenhao; Zhang, Jie; Tong, Jian; Song, Xuehong

2016-07-01

Hypoxia is a relevant physiological challenge for crab culture, and the hemolymph plays a crucial role in response to the hypoxia. In a 60 d feeding trial, Chinese mitten crabs (Eriocheir sinensis) fed a diet containing 0.2 mg/kg nano-selenium (nanoSe) showed a significantly increased weight gain rate (WGR) and a reduced feed coefficient (FC) compared to those fed diets with 0, 0.1, 0.4, 0.8, and 1.6 mg/kg nanoSe. Another 90 d feeding trial was conducted to determine the influence of dietary nanoSe on the immune response in juvenile Chinese mitten crabs kept under the condition of hypoxia. The results showed that hypoxia stress resulted in significantly increased hemocyte counts (THC, LGC, SGC, and HC), expression levels of the hemocyanin gene and protein, lactic acid level, and antioxidant capacity (T-AOC activities, SOD activities, GSH-Px and GSH content) in hemolymph supernatant. When these crabs were infected with Aeromonas hydrophila bacteria, hypoxia exposure increased mortality, but it was alleviated by a diet supplemented with 0.2 mg/kg nanoSe. The up-regulative effects of nanoSe (0.2 mg/kg) on antioxidant capacity, hemocyte counts, and hemocyanin expression under hypoxia exposure were further strengthened throughout, whereas lactic acid levels induced by hypoxia stress were restored. Thus, the observations in this study indicate that the level of dietary nanoSe is important in regulating immunity and disease resistance in crabs kept under hypoxia stress. Copyright © 2016 Elsevier Ltd. All rights reserved.

Molecular and immunological approaches in quantifying the air-borne food allergen tropomyosin in crab processing facilities.

PubMed

Kamath, Sandip D; Thomassen, Marte R; Saptarshi, Shruti R; Nguyen, Hong M X; Aasmoe, Lisbeth; Bang, Berit E; Lopata, Andreas L

2014-09-01

Tropomyosin is a cross-reactive allergenic protein present in ingested shellfish species. Exposure and sensitization to this protein via inhalation is particularly important in the crustacean processing industry where workers are continuously exposed to the aerosolized form of this allergen. The aim of this study was to develop an antibody-based immunoassay to enable the specific and sensitive quantification of aerosolized tropomyosin present in the environment of two crab processing facilities. Anti-tropomyosin antibody was generated in rabbits against tropomyosins from four different crustacean species. These antibodies were purified using recombinant tropomyosin using an immuno-affinity column. The recombinant tropomyosin was also used as an allergen standard for the sandwich ELISA. In order to quantify aerosolized tropomyosin, air collection was performed in the personal breathing zone of 80 workers during two crab processing activities, edible crab (Cancer pagurus) and king crab (Paralithodes camtschaticus) using polytetrafluoroethylene filters. The purified antibody was able to detect tropomyosin selectively from different crustaceans but not from vertebrate sources. The limit of detection (LOD) for the developed sandwich ELISA was 60 picogram/m(3) and limit of quantitation (LOQ) 100 picogram/m(3). Immunoassay validation was based on linearity (R(2) 0.999), matrix interference test (78.8±6.5%), intra-assay CV (9.8%) and inter-assay CV (11%). The novel immunoassay was able to successfully identify working activities, which generated low, medium or high concentrations of the aerosolized food allergen. We describe an IgG antibody-based immunoassay for quantification of the major food allergen tropomyosin, with high sensitivity and specificity. This modified immunological approach can be adapted for the detection of other aerosolized food allergens, assisting in the identification of high-risk allergen exposure areas in the food industry. Copyright © 2014

Identification of the major allergens of Charybdis feriatus (red crab) and its cross-reactivity with Portunus pelagicus (blue crab).

PubMed

Misnan, Rosmilah; Murad, Shahnaz; Yadzir, Zailatul Hani Mohd; Abdullah, Noormalin

2012-12-01

Tropomyosin and arginine kinase have been identified as the major allergens in multiple species of crab. Charybdis feriatus is an important commercial crab in this country. To characterize the major allergens of C. feriatus using a proteomics approach and subsequently to identify the allergens involved in cross-reactivity with Portunus pelagicus. Raw and boiled extracts of the crabs were prepared from crab meat. The protein profile of the extracts was determined by SDS-PAGE and two-dimensional electrophoresis (2-DE). Major allergens were identified by the immunoblotting test using sera from 50 patients with crab allergy. The major allergens were further identified by 2-DE immunoblotting. The major allergenic spots were then excised, digested by trypsin and identified by mass spectrometry analysis. The immunoblotting inhibition test was performed to study the crossreactivity between red crab and blue crab allergens using sera from 20 patients with allergy to both red and blue crabs. At least 20 protein bands between 13 to 250 kDa were detected in the SDS-PAGE gel of raw extract, while boiled extract procuced fewer protein bands. Proteins of 36 kDa and 41 kDa were recognized as the major allergens of the crab. The major allergenic spot sequences of the 36 and 41 kDa proteins were identified as crab tropomyosin and arginine kinase, respectively. All IgE-binding proteins, including both major allergens, were found to be cross-creative with P. pelagicus allergens. In addition to tropomyosin, arginine kinase was also identified as the major allergen of C. feriatus among our local crab-allergic patients. Cross-reactivity of this crab with P. pelagicus was demonstrated in this study.

Bdellovibrios in Callinectus sapidus, the Blue Crab

PubMed Central

Kelley, Jacqueline I.; Williams, Henry N.

1992-01-01

Bdellovibrios were recovered from the gill tissue of all of 31 crabs sampled and from all samples of epibiota obtained from the ventral shell surface of 15 crabs. The results suggest that the blue crab is a reservoir for bdellovibrios. The association with crabs may be an important factor in the ecology of the bdellovibrios. PMID:16348706

Species-specific crab predation on the hydrozoan clinging jellyfish Gonionemus sp. (Cnidaria, Hydrozoa), subsequent crab mortality, and possible ecological consequences.

PubMed

Carman, Mary R; Grunden, David W; Govindarajan, Annette F

2017-01-01

Here we report a unique trophic interaction between the cryptogenic and sometimes highly toxic hydrozoan clinging jellyfish Gonionemus sp. and the spider crab Libinia dubia . We assessed species-specific predation on the Gonionemus medusae by crabs found in eelgrass meadows in Massachusetts, USA. The native spider crab species L. dubia consumed Gonionemus medusae, often enthusiastically, but the invasive green crab Carcinus maenus avoided consumption in all trials. One out of two blue crabs ( Callinectes sapidus ) also consumed Gonionemus , but this species was too rare in our study system to evaluate further. Libinia crabs could consume up to 30 jellyfish, which was the maximum jellyfish density treatment in our experiments, over a 24-hour period. Gonionemus consumption was associated with Libinia mortality. Spider crab mortality increased with Gonionemus consumption, and 100% of spider crabs tested died within 24 h of consuming jellyfish in our maximum jellyfish density containers. As the numbers of Gonionemus medusae used in our experiments likely underestimate the number of medusae that could be encountered by spider crabs over a 24-hour period in the field, we expect that Gonionemus may be having a negative effect on natural Libinia populations. Furthermore, given that Libinia overlaps in habitat and resource use with Carcinus , which avoids Gonionemus consumption, Carcinus populations could be indirectly benefiting from this unusual crab-jellyfish trophic relationship.

Effects of dietary peppermint (Mentha piperita) essential oil on survival, growth, cannibalism and hepatopancreatic histopathology of Portunus pelagicus juveniles.

PubMed

Roslan, Syahirah; Taher, Sofea; Ehteshamei, Fariborz; Arshad, Aziz; Romano, Nicholas

2016-07-01

A two-part experiment was performed to determine whether dietary peppermint oil could improve the growth and/or decrease aggression among blue swimmer crab, Portunus pelagicus early juveniles. A total of five isonitrogenous diets were made that contained increasing peppermint oil levels of 0.00, 0.05, 0.10, 0.50 or 1.00%.? These diets were fed to 45 replicate crabs in each treatment (total of 225 crabs) for 12 days, the final sizes and weights were measured, and then placed in 3 replicate containers (30 in total/treatment) to allow the opportunity for cannibalism over 10 days.? After 10 days, the remaining crabs were examined for any histopathological changes in gills or hepatopancreas.? Results showed dietary peppermint oil, at the tested levels, had no effect on the growth or cannibalism, in either experiments (p > 0.05).? However, there were substantial changes in the hepatopancreatic histopathology that included thinner tubules and significantly less B- and R-cells from 0.10% dietary peppermint oil and above.? The unaffected growth or cannibalism indicate that the levels of dietary peppermint oil used were insufficient and further investigations are required, particularly on the implications to the hepatopancreatic changes. ?

[The dementia of King Ferdinand VI and the year with no king].

PubMed

Fernandez-Menendez, S; Gonzalez-Gonzalez, J M; Alvarez-Antuna, V; Bobes, J

2016-06-01

Ferdinand VI was king of Spain from 1746 until 1759. His last year of reign is known as the year without a king. Over this year the king suffered a rapidly progressive deterioration of his mental health status. The clinical condition has been always attributed to a pure psychiatric disorder, generally a bipolar disorder. We review the sources of information in the Spanish archives and libraries, in order to find clinical information about the illness suffered by the king. We made a clinical evaluation and discussion about the disease of the king according to the information that has been obtained and the different diseases that could have caused the illness. Last year clinical deterioration of Ferdinand VI started with the death of his lovely wife. At first, the symptoms were similar to the symptoms of a mayor depressive disorder. Although the king had a rapidly progressive deterioration with severe changes in behavior and conduct, long stay in bed, loss of sphincters control and seizures. During the last months of his life, the king fell into a state of prostration with a marked cognitive impairment. Although it is possible that Ferdinand VI could have had a previous psychiatric disorder, there is enough information to think about a rapidly progressive dementia as the main cause of his clinical worsening and dead.

Antarctic Crabs: Invasion or Endurance?

PubMed Central

Griffiths, Huw J.; Whittle, Rowan J.; Roberts, Stephen J.; Belchier, Mark; Linse, Katrin

2013-01-01

Recent scientific interest following the “discovery” of lithodid crabs around Antarctica has centred on a hypothesis that these crabs might be poised to invade the Antarctic shelf if the recent warming trend continues, potentially decimating its native fauna. This “invasion hypothesis” suggests that decapod crabs were driven out of Antarctica 40–15 million years ago and are only now returning as “warm” enough habitats become available. The hypothesis is based on a geographically and spatially poor fossil record of a different group of crabs (Brachyura), and examination of relatively few Recent lithodid samples from the Antarctic slope. In this paper, we examine the existing lithodid fossil record and present the distribution and biogeographic patterns derived from over 16,000 records of Recent Southern Hemisphere crabs and lobsters. Globally, the lithodid fossil record consists of only two known specimens, neither of which comes from the Antarctic. Recent records show that 22 species of crabs and lobsters have been reported from the Southern Ocean, with 12 species found south of 60°S. All are restricted to waters warmer than 0°C, with their Antarctic distribution limited to the areas of seafloor dominated by Circumpolar Deep Water (CDW). Currently, CDW extends further and shallower onto the West Antarctic shelf than the known distribution ranges of most lithodid species examined. Geological evidence suggests that West Antarctic shelf could have been available for colonisation during the last 9,000 years. Distribution patterns, species richness, and levels of endemism all suggest that, rather than becoming extinct and recently re-invading from outside Antarctica, the lithodid crabs have likely persisted, and even radiated, on or near to Antarctic slope. We conclude there is no evidence for a modern-day “crab invasion”. We recommend a repeated targeted lithodid sampling program along the West Antarctic shelf to fully test the validity of the �

Preliminary Assessment of Potential Impacts to Dungeness Crabs from Disposal of Dredged Materials from the Columbia River

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

Pearson, Walter H.; Miller, Martin C.; Williams, Greg D.

2006-02-01

), short-duration disposal scenarios, the shear force and surge currents estimated from the modeling and observed previously in the field at Palos Verdes, California appear to be sufficiently high to mobilize and transport the bottom sediment and at least juvenile crab. Behavioral response to surge currents probably occurs and may reduce the occurrence and extent of movement and any associated impacts. There evidence that burial by dredged materials can effect crab survival, but confounding factors in previous experiments preclude conclusions about thresholds and extent of effects. We recommend that future studies focus on burial effects during shallow water, short duration disposal events and take into account the potential for behavioral responses to mitigate any effects.« less

Species–specific crab predation on the hydrozoan clinging jellyfish Gonionemus sp. (Cnidaria, Hydrozoa), subsequent crab mortality, and possible ecological consequences

PubMed Central

Carman, Mary R.; Grunden, David W.

2017-01-01

Here we report a unique trophic interaction between the cryptogenic and sometimes highly toxic hydrozoan clinging jellyfish Gonionemus sp. and the spider crab Libinia dubia. We assessed species–specific predation on the Gonionemus medusae by crabs found in eelgrass meadows in Massachusetts, USA. The native spider crab species L. dubia consumed Gonionemus medusae, often enthusiastically, but the invasive green crab Carcinus maenus avoided consumption in all trials. One out of two blue crabs (Callinectes sapidus) also consumed Gonionemus, but this species was too rare in our study system to evaluate further. Libinia crabs could consume up to 30 jellyfish, which was the maximum jellyfish density treatment in our experiments, over a 24-hour period. Gonionemus consumption was associated with Libinia mortality. Spider crab mortality increased with Gonionemus consumption, and 100% of spider crabs tested died within 24 h of consuming jellyfish in our maximum jellyfish density containers. As the numbers of Gonionemus medusae used in our experiments likely underestimate the number of medusae that could be encountered by spider crabs over a 24-hour period in the field, we expect that Gonionemus may be having a negative effect on natural Libinia populations. Furthermore, given that Libinia overlaps in habitat and resource use with Carcinus, which avoids Gonionemus consumption, Carcinus populations could be indirectly benefiting from this unusual crab–jellyfish trophic relationship. PMID:29085761

Dispersal, movements and site fidelity of post-fledging King Eiders Somateria spectabilis and their attendant females

USGS Publications Warehouse

Bentzen, Rebecca L.; Powell, Abby N.

2015-01-01

Post-fledging dispersal and site fidelity are poorly understood, particularly for sea ducks that spend the majority of their annual cycle at sea. This is the first description of movements and their timing for first-year (juvenile) and second-year (subadult) King Eiders Somateria spectabilis in relation to their attendant females. We fitted satellite transmitters that operated for 2 years to 63 hatch-year birds and 17 attendant females at breeding areas in northern Alaska in 2006–2009. Our goals were to describe the spatio-temporal distribution of pre-breeding individuals and adult females that had been successful breeders. We also examined fidelity to wing moulting and wintering areas as well as natal philopatry. Juveniles did not appear to follow attendant adults, although they did winter in the same three general wintering areas, suggesting that genetic inheritance and social factors may have roles in the initial migration from the breeding area. Additionally, juveniles were more variable in the timing and duration of migration, moved longer distances during the winter, and were less faithful to moulting and wintering areas than adults, indicating that individual exploration and acquired navigational memory played a role in subsequent migrations. Most (75%) subadult females returned to natal areas, probably prospecting for future nesting sites, whereas subadult males were widely dispersed at sea. Timing and duration of moult migration and wing moult of adult females that were presumed to be successful breeders differed from those of unsuccessful breeders due to the extended time that the former spent on the breeding grounds. Temporal and spatial segregation of post-fledging King Eiders from adults has direct management implications in terms of resource development and population dynamics.

50 CFR 680.21 - Crab harvesting cooperatives.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Minimum number of members. Each crab harvesting cooperative must include at least four unique QS holding... IFQ permit issued to the crab harvesting cooperative for the current fishing season. (2) Transfer of... voluntary. A crab harvesting cooperative is not required to add or remove members during the fishing season...

50 CFR 680.21 - Crab harvesting cooperatives.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Minimum number of members. Each crab harvesting cooperative must include at least four unique QS holding... IFQ permit issued to the crab harvesting cooperative for the current fishing season. (2) Transfer of... voluntary. A crab harvesting cooperative is not required to add or remove members during the fishing season...

EFFECTS OF THE INSECT JUVENILE HORMONE AGONIST, METHOPRENE, ON FEMALE GROWTH AND REPRODUCTION IN THE GULF SAND FIDDLER CRAB.

EPA Science Inventory

Adult Uca panacea were collected from the shores of West Bay Point near Panama City, Florida, in late April of 2000. These crabs (250 females, 100 males per pond) were distributed randomly into six specially constructed estuarine ponds to determine the effects of field applicatio...

75 FR 55744 - North Pacific Fishery Management Council; Public Meetings

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-14

... priorities. 9. BSAI Crab Issues: Initial review Pribilof Bristol Bay Red King Crab rebuilding plan; review... Aleutian Island (BSAI Crab Stock Assessment Fishery Evaluation (SAFE) report and Overfishing Limits (OFLs): Review and approve SAFE and annual catch specifications. 4. BSAI Crab Annual Catch Limits (ACLs)/snow...

50 CFR 679.31 - CDQ and PSQ reserves.

Code of Federal Regulations, 2010 CFR

2010-10-01

... point where the boundary of the IPHC regulatory area intersects land. (3) Crab CDQ reserves. Crab CDQ reserves for crab species governed by the Crab Rationalization Program are specified at § 680.40 (a)(1). For Norton Sound red king crab, 7.5 percent of the guideline harvest level specified by the State of...

50 CFR 679.31 - CDQ and PSQ reserves.

Code of Federal Regulations, 2011 CFR

2011-10-01

... point where the boundary of the IPHC regulatory area intersects land. (3) Crab CDQ reserves. Crab CDQ reserves for crab species governed by the Crab Rationalization Program are specified at § 680.40 (a)(1). For Norton Sound red king crab, 7.5 percent of the guideline harvest level specified by the State of...

Monitoring the Crab Nebula with LOFT

NASA Technical Reports Server (NTRS)

Wilson-Hodge, Colleen A.

2012-01-01

From 2008-2010, the Crab Nebula was found to decline by 7% in the 15-50 keV band, consistently in Fermi GBM, INTEGRAL IBIS, SPI, and JEMX, RXTE PCA, and Swift BAT. From 2001-2010, the 15-50 keV flux from the Crab Nebula typically varied by about 3.5% per year. Analysis of RXTE PCA data suggests possible spectral variations correlated with the flux variations. I will present estimates of the LOFT sensitivity to these variations. Prior to 2001 and since 2010, the observed flux variations have been much smaller. Monitoring the Crab with the LOFT WFM and LAD will provide precise measurements of flux variations in the Crab Nebula if it undergoes a similarly active episode.

Mitigating by-catch of diamondback terrapins in crab pots

USGS Publications Warehouse

Hart, Kristen M.; Crowder, Larry B.

2011-01-01

Chronic by-catch of diamondback terrapins (Malaclemys terrapin) in blue crab (Callinectes sapidus) pots is a concern for terrapin conservation along the United States Atlantic and Gulf of Mexico coasts. Despite the availability of by-catch reduction devices (BRDs) for crab pots, adoption of BRDs has not been mandated and by-catch of terrapins continues. We conducted experimental fishing studies in North Carolina's year-round blue crab fishery from 2000 to 2004 to evaluate the ability of various BRDs to reduce terrapin by-catch without a concomitant reduction in the catch of blue crabs. In 4,822 crab pot days fished, we recorded only 21 terrapin captures. Estimated capture rates were 0.003 terrapins/pot per day in hard crab experimental fishing and 0.008 terrapins/pot per day in peeler experimental fishing. All terrapin captures occurred from April to mid-May within 321.4 m of the shoreline. Longer soak times produced more dead terrapins, with 4 live and 4 dead during hard crab experimental fishing and 11 live and 2 dead during peeler experimental fishing. The 4.0-cm BRDs in fall and 4.5-cm and 5.0-cm BRDs in spring reduced the catch of legal-sized male hard crabs by 26.6%, 21.2%, and 5.7%, respectively. Only the 5.0-cm BRDs did not significantly affect the catch of legal-sized hard male crabs. However, BRDs had no measurable effect on catch of target crabs in the peeler crab fishery. Our results identify 3 complementary and economically feasible tools for blue crab fishery managers to exclude terrapins from commercially fished crab pots in North Carolina: 1) gear modifications (e.g., BRDs); 2) distance-to-shore restrictions; and 3) time-of-year regulations. These measures combined could provide a reduction in terrapin by-catch of up to 95% without a significant reduction in target crab catch.

50 CFR 648.263 - Red crab possession and landing restrictions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 10 2011-10-01 2011-10-01 false Red crab possession and landing... Management Measures for the Atlantic Deep-Sea Red Crab Fishery § 648.263 Red crab possession and landing restrictions. (a) Vessels issued limited access red crab permits. (1) [Reserved] (2) Conversion to whole crab...

Ecophysiological adaptations to variable salinity environments in the crab Hemigrapsus crenulatus from the Southeastern Pacific coast: Sodium regulation, respiration and excretion.

PubMed

Urzúa, Ángel; Urbina, Mauricio A

2017-08-01

The estuarine crab Hemigrapsus crenulatus is a key benthic species of estuarine and intertidal ecosystems of the South Pacific, habitats that experience wide fluctuations in salinity. The physiological strategies that allow this crab to thrive under variable salinities, and how they change during the benthic stages of their life cycle, were evaluated under laboratory conditions. Oxygen consumption, ammonia excretion and the regulatory capacity of Na + through the normal range of environmental salinities (i.e. 5, 10, 15, 20, 25, 30) were evaluated in three size classes, ranging from juveniles to adults. In all sizes, the oxygen consumption, ammonia excretion and regulatory capacity of Na + decreased as salinity increased, with the highest values at 5 and the lowest values at 30 salinity. Bigger crabs showed a higher capacity to regulate Na + , as well as higher respiration and excretion rates compared to smaller crabs, suggesting that they are better equipped to exploit areas of the estuary with low salinity. Regardless of its size, H. crenulatus is a strong hyper regulator in diluted media (i.e. 5-20) while a conformer at salinities higher than 20. The regulatory capacity of Na + was positively related with oxygen consumption and ammonia excretion rates. These relationships between sodium regulation, respiration and excretion are interpreted as adaptive physiological mechanisms that allow H. crenulatus to maintain the osmotic and bioenergetic balance over a wide range of environmental salinities. Copyright © 2017 Elsevier Inc. All rights reserved.

The Porcelain Crab Transcriptome and PCAD, the Porcelain Crab Microarray and Sequence Database

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

Tagmount, Abderrahmane; Wang, Mei; Lindquist, Erika

2010-01-27

Background: With the emergence of a completed genome sequence of the freshwater crustacean Daphnia pulex, construction of genomic-scale sequence databases for additional crustacean sequences are important for comparative genomics and annotation. Porcelain crabs, genus Petrolisthes, have been powerful crustacean models for environmental and evolutionary physiology with respect to thermal adaptation and understanding responses of marine organisms to climate change. Here, we present a large-scale EST sequencing and cDNA microarray database project for the porcelain crab Petrolisthes cinctipes. Methodology/Principal Findings: A set of ~;;30K unique sequences (UniSeqs) representing ~;;19K clusters were generated from ~;;98K high quality ESTs from a set ofmore » tissue specific non-normalized and mixed-tissue normalized cDNA libraries from the porcelain crab Petrolisthes cinctipes. Homology for each UniSeq was assessed using BLAST, InterProScan, GO and KEGG database searches. Approximately 66percent of the UniSeqs had homology in at least one of the databases. All EST and UniSeq sequences along with annotation results and coordinated cDNA microarray datasets have been made publicly accessible at the Porcelain Crab Array Database (PCAD), a feature-enriched version of the Stanford and Longhorn Array Databases.Conclusions/Significance: The EST project presented here represents the third largest sequencing effort for any crustacean, and the largest effort for any crab species. Our assembly and clustering results suggest that our porcelain crab EST data set is equally diverse to the much larger EST set generated in the Daphnia pulex genome sequencing project, and thus will be an important resource to the Daphnia research community. Our homology results support the pancrustacea hypothesis and suggest that Malacostraca may be ancestral to Branchiopoda and Hexapoda. Our results also suggest that our cDNA microarrays cover as much of the transcriptome as can reasonably be

Pubic "Crab" Lice Prevention and Control

MedlinePlus

... and General Public. Contact Us Parasites Home Prevention & Control Recommend on Facebook Tweet Share Compartir Pubic ("crab") ... that can be taken to help prevent and control the spread of pubic ("crab") lice: All sexual ...

Uncoupling effect of palmitate is exacerbated in skeletal muscle mitochondria of sea-acclimatized king penguins (Aptenodytes patagonicus).

PubMed

Rey, Benjamin; Duchamp, Claude; Roussel, Damien

2017-09-01

In king penguin juveniles, the environmental transition from a terrestrial to a marine habitat, occurring at fledging, drastically stimulates lipid catabolism and the remodelling of muscle mitochondria to sustain extensive swimming activity and thermoregulation in the cold circumpolar oceans. However, the exact nature of these mechanisms remains only partially resolved. Here we investigated, in vitro, the uncoupling effect of increasing doses of fatty acids in pectoralis muscle intermyofibrillar mitochondria isolated, either from terrestrial never-immersed or experimentally cold water immersed pre-fledging king penguins or from sea-acclimatized fledged penguins. Mitochondria exhibited much greater palmitate-induced uncoupling respiration and higher maximal oxidative capacity after acclimatization to marine life. Such effects were not reproduced experimentally after repeated immersions in cold water, suggesting that the plasticity of mitochondrial characteristics may not be primarily driven by cold exposure per se but by other aspects of sea acclimatization. Copyright © 2017. Published by Elsevier Inc.

Species profiles: Life history and environmental requirements of coastal fishes and invertebrates (South Florida): King mackerel and Spanish mackerel. [Scomberomorus cavalla; Scomberomorus maculatus

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

Godcharles, M.F.; Murphy, M.D.

1986-06-01

This Species Profile on king and Spanish mackerel summarizes the taxonomy, morphology, distribution, life history, fishery descriptions, ecological role, and environmental requirements of these coastal pelagic fish to assist environmental impact assessment. King and Spanish mackerel support major commercial and sport fisheries in south Florida. In 1974 to 1983, Gulf of Mexico and Atlantic commercial landings of king mackerel declined from 10.4 to 4.3 million lb.; Spanish mackerel have fluctuated between 4.9 to 17.4 million lb. Both inhabit coastal waters, but Spanish mackerel are generally found closer to beaches and in outer estuarine waters. Both species feed principally on estuarine-dependentmore » species. They are highly migratory, exhibiting seasonal migrations to winter feeding grounds off south Florida and summer spawning/feeding grounds in the northern Gulf of Mexico and off the Atlantic coast of the Southeastern US. Spawning occurs from March/April through September/October between the middle and Outer Continental Shelf (35 to 183 mi) for king mackerel and the inner shelf (12 to 34 mi) for Spanish mackerel. King mackerel reach sexual maturity in their 3rd and 4th years and Spanish, between their 2nd and 3rd. Female king mackerel live longer and grow larger and faster than males. Spanish mackerel live to 8 years; females also grow faster than males. King and Spanish mackerel feed principally on schooling fishes. Larvae and juveniles of both species are prey to little tunny and dolphin; adults are prey for sharks and bottlenose dolphin. Temperature and salinity are important factors regulating mackerel distribution.« less

Hermit crabs, humans and crowded house markets.

PubMed

Barnes, David K A

2002-12-01

There is a complex and dynamic interrelationhip between hermit crabs, humans and the coastal environment. Hermit crab homes (shells) are often hard to come by, but humans are helping out by piling middens of shells and rubbish on beachers. Hermit crabs are useful to humans as fishing bait, pets and living wasted disposal systems, and so useful to other animals that they may even be hijacked.

Acute toxicity of sodium metabisulphite in larvae and post-larvae of the land crab, Cardisoma guanhumi.

PubMed

Galli, Orlando B S; Fujimoto, Rodrigo Y; Abrunhosa, Fernando A

2012-08-01

Sodium metabisulphite (SMB) is used in marine shrimp aquaculture to prevent the occurrence of black spot. The release SMB into the estuarine environment from shrimp farm pond effluents has been reported. This study evaluated the susceptibility of larvae and post-larvae of land crab, Cardisoma guanhumi to this salt. A decrease in dissolved oxygen and pH occurred with increasing concentration of SMB and exposure time. LC(50) values after 48 h of exposure were 34 ± 1.1 mg/L, 31.1 ± 1.9 mg/L, and 30.6 ± 0.5 mg/L for I zoea larvae, megalopa larvae and stage I juveniles, respectively.

Dr. King's Dream. [Lesson Plan].

ERIC Educational Resources Information Center

National Endowment for the Humanities (NFAH), Washington, DC.

This lesson plan teaches students about the life and work of Martin Luther King, Jr. Students listen to a brief biography, view photographs of the March on Washington, hear a portion of King's "I Have a Dream" speech, and discuss what King's words mean to them. Finally, they will create picture books about their own dreams of freedom for…

The True Lion King of Africa: The Epic History of Sundiata, King of Old Mali.

ERIC Educational Resources Information Center

Paterno, Domenica R.

David Wisniewski's 1992 picture book version of the African epic of "Sundiata, Lion King of Mali" and the actual historical account of the 13th century Lion King, Sundiata, are both badly served by Disney's "The Lion King." Disney has been praised for using African animals as story characters; for using the African landscape as…

77 FR 29593 - North Pacific Fishery Management Council; Public Meetings

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-18

... Particular Concern (HAPC) skate egg sites. 4. BSAI Crab Rebuilding Crab Plan Team report on Set catch Specifications for 4 stocks; Final action on Pribilof Bristol Bay Red King Crab rebuilding plan. 5. Freezer... and tasking. 8. Other Business The SSC agenda will include the following issues: 1. EFH 2. BSAI Crab...

The population biology and genetics of the deep-sea spider crab, Encephaloides armstrongi Wood-Mason 1891 (Decapoda: Majidae)

PubMed Central

Creasey, S.; Rogers, A. D.; Tyler, P.; Young, C.; Gage, J.

1997-01-01

Numerous specimens of the majid spider crab, Encephaloides armstrongi, were sampled from six stations (populations) between 150 and 650 m depth, on the continental slope off the coast of Oman. This extended the known geographic and bathymetric range of E. armstrongi, which is now known to occur along the continental margins of the northern Indian Ocean from the western coast of Burma to the coast of Oman. This band-like distribution is contiguous to the oxygen minimum zone in this region. The biology and genetics of populations of Encephaloides armstrongi separated by depth were studied. The overall sex ratio of the E. armstrongi sampled was male-biased (p less than 0.01; 3.3 males: 1 female; So = 0.538). However, sex ratio varied both between populations (p less than 0.01) and between size classes of crabs. Size frequency analysis indicated that the male and female crabs consisted of at least two instars, one between 6 and 16mm carapace length and one between 16 and 29 mm carapace length, which probably represented the terminal (pubertal) moult for most individuals. Accumulation of female crabs in the terminal instar probably caused the variation of sex ratio with size classes. Some male crabs grew to a larger size (up to 38 mm carapace length), possibly as a result of maturity at later instars. Length frequency distribution was significantly different between sexes (one-way ANOVA p less than 0.001). Within sexes, length frequency distributions varied between different populations. In both male and female Encephaloides armstrongi the individuals from a single population located at 150 m depth were significantly smaller than individuals at all other stations and were considered to represent a juvenile cohort. For female crabs no other significant differences were detected in length frequency between populations from 300 m to 650 m depth. Significant differences in length frequency were detected between male crabs from populations between 300 and 650 m depth

Potential Impact of Submarine Power Cables on Crab Harvest

NASA Astrophysics Data System (ADS)

Bull, A. S.; Nishimoto, M.

2016-02-01

Offshore renewable energy installations convert wave or wind energy to electricity and transfer the power to shore through transmission cables laid on or buried beneath the seafloor. West coast commercial fishermen, who harvest the highly prized Dungeness crab (Metacarcinus magister) and the rock crab (Cancer spp.), are concerned that the interface of crabs and electromagnetic fields (EMF) from these cables will present an electrified fence on the seafloor that their target resource will not cross. Combined with the assistance of professional fishermen, submarine transmission cables that electrify island communities and offshore oil platforms in the eastern Pacific provide an opportunity to test the harvest of crab species across power transmission cables. In situ field techniques give commercial crab species a choice to decide if they will cross fully energized, EMF emitting, power transmission cables, in response to baited traps. Each independent trial is either one of two possible responses: the crab crosses the cable to enter a trap (1) or the crab does not cross the cable to enter a trap (0). Conditions vary among sample units by the following categorical, fixed factors (i.e., covariates) of cable structure (buried or unburied); direction of cable from crab position (west or east, north or south); time and season. A generalized linear model is fit to the data to determine whether any of these factors affect the probability of crabs crossing an energized cable to enter baited traps. Additionally, the experimental design, aside from the number of runs (set of sample trials) and the dates of the runs, is the same in the Santa Barbara Channel for rock crab and Puget Sound for Dungeness crab, and allows us to compare the capture rates of the two species in the two areas. We present preliminary results from field testing in 2015.

Effect of Mudflat Trampling on Activity of Intertidal Crabs

NASA Astrophysics Data System (ADS)

Kim, Tae Won; Kim, Sanha; Lee, Jung-Ah

2018-03-01

Many people visit intertidal mudflats to collect bait and seafood, or for eco-tourism and recreation, and as a consequence trample on the mudflats frequently. Trampling would not be life threatening to most animals in the intertidal flats as they have evolved hiding behavior to escape predation. However, what is the effect of trampling on the behavior of intertidal animals? In this study, the effect of mudflat trampling on the activity of crabs (e.g. fiddler crabs, sentinel crabs) living on the mudflat was explored. The number of crabs active on the mudflat surface in experimental plots (1.5 × 1.5 m2) before and after (10 min. and 30 min.) trampling of three different intensities (Heavy trampling = 60 steps; Moderate trampling = 20 steps; and No trampling) was compared in two different mudflat systems. After trampling, the number of crabs active on the surface decreased and was significantly lower than that of control plots. The more intensively trampled the mudflat was, the fewer crabs were active on the mudflat surface. Surprisingly, the number of active crabs did not recover even 30 min. after trampling. The results clearly support the hypothesis that trampling can severely interfere with the behavior of crabs living on intertidal mudflats.

Metabolic Response of Dungeness Crab Larvae Exposed to Elevated CO2 and Hypoxia

NASA Astrophysics Data System (ADS)

Nichols, Z.; Busch, S.; McElhany, P.

2015-12-01

Ocean acidification (OA) and deoxygenation, both resulting from rising atmospheric CO2 levels, are lowering the pH and oxygen levels of global oceans. Assessing the impacts of OA and deoxygenation on harvested species is crucial for guiding resource management with the aim of maintaining healthy and sustainable populations. The Dungeness crab, Cancer magister, is an important species ecologically and economically for the US West Coast. Crabs transition through four main stages: zoea, megalopa, juvenile, and adult. Each stage results in a different morphology and behavior, and as a result, is exposed to various environmental parameters, such as pH and dissolved oxygen (DO). The first two stages exhibit diel vertical migration while the final stages are benthic. Our study focused on the megalopae stage and their metabolic response to OA and hypoxia. We exposed wild-caught megalopae to a pH x DO cross, producing treatment waters with combinations of low or high pH and O2, all maintained at 12˚C. Closed-chamber respirometry was used to compare standard metabolic rates in a common garden setting with high pH/high DO conditions. We predict that the megalopae exposed to the low pH/high DO treatment will have a higher metabolic rate than those exposed to the high pH/high DO treatment. This may be a result of homeostatic processes increasing to return the megalopae's internal pH back to equilibrium. We predict that the high pH/low DO treatment will cause a decrease in metabolism when compared to the high pH/high DO treatment due to the megalopae conserving oxygen in a limiting environment. If results support our hypothesis, they would suggest that OA and hypoxia affects Dungeness crabs in sublethal ways.

The Crab Boat Engineering Design Challenge

ERIC Educational Resources Information Center

Love, Tyler S.; Ryan, Larry

2017-01-01

Crab cakes and football, that's what Maryland does!" (Abrams, Levy, Panay, & Dobkin, 2005). Although the Old Line State is notorious for harvesting delectable blue crabs, the movie "Wedding Crashers" failed to highlight something else Maryland does well: engineering design competitions. This article discusses how a multistate…

Ocean acidification impairs crab foraging behaviour

PubMed Central

Dodd, Luke F.; Grabowski, Jonathan H.; Piehler, Michael F.; Westfield, Isaac; Ries, Justin B.

2015-01-01

Anthropogenic elevation of atmospheric CO2 is driving global-scale ocean acidification, which consequently influences calcification rates of many marine invertebrates and potentially alters their susceptibility to predation. Ocean acidification may also impair an organism's ability to process environmental and biological cues. These counteracting impacts make it challenging to predict how acidification will alter species interactions and community structure. To examine effects of acidification on consumptive and behavioural interactions between mud crabs (Panopeus herbstii) and oysters (Crassostrea virginica), oysters were reared with and without caged crabs for 71 days at three pCO2 levels. During subsequent predation trials, acidification reduced prey consumption, handling time and duration of unsuccessful predation attempt. These negative effects of ocean acidification on crab foraging behaviour more than offset any benefit to crabs resulting from a reduction in the net rate of oyster calcification. These findings reveal that efforts to evaluate how acidification will alter marine food webs should include quantifying impacts on both calcification rates and animal behaviour. PMID:26108629

Are vent crab behavioral preferences adaptations for habitat choice?

PubMed

Dahms, Hans-Uwe; Tseng, Li-Chun; Hwang, Jiang-Shiou

2017-01-01

Hydrothermal vent organisms are adapted to their extreme and patchily distributed habitats. They are expected to have evolved mechanisms that keep them in their specific habitation. Since little is known about the recruitment or habitat selection of HV organisms such as brachyurans, we examined the properties of several hydrothermal vent-associated cues on the behavior of the hydrothermal vent (HV) crab Xenograpsus testudinatus in the laboratory that were contrasted by the offering of non-vent cues. This crab species is endemic and dominates the vent fauna of Turtle Island off the NE coast of Taiwan. HV crabs were separately and in combination offered the following vent-specific cues: (1) sulfuric sediment, (3) air-bubbling, (4) elevated temperature, (5) dead settled zooplankton, (7) other crabs, and (8) shade. The non-vent-specific cues were: (2) quarz sediment, (6) dead fish, (8) light. These cues were provided on either side of a two-choice chamber. The movement of individual crabs was monitored: as initial and final choices, and as the proportion of time the crabs spent in each compartment (resident time). Cues were offered alone and no such cue as a control in the same set-up. Sulfuric sediments and dead fish were significantly more attractive to females, and other crabs irrespective of gender were significantly more attractive to males. When compared to expected distributions, crabs, irrespective of gender, significantly avoided light and tended to select other crabs, air-bubbling, sulfuric sediment, elevated temperature, dead fish, dead zooplankton, and quarz sediments in the order of decreasing importance. Data do not support the hypothesis that dead settled zooplankton was particularly attractive nor that the other gender was selected. A combination of several vent-associated cues (sulfuric sediment, elevated temperature, air-bubbling) facilitated the strongest attraction to the crabs as reflected by all response variables. The 'first choice' responses

Changing trends in the incidence of juvenile nasopharyngeal angiofibroma: seven decades of experience at King George's Medical University, Lucknow, India.

PubMed

Mishra, A; Mishra, S C

2016-04-01

The occurrence of juvenile nasopharyngeal angiofibroma is reportedly higher in India than in some other parts of the world, and our centre has seen a four-fold increase in its occurrence across seven decades. This paper reports a retrospective archival analysis of 701 juvenile nasopharyngeal angiofibroma cases from 1958 to 2013, and considers probable environmental factors in an Indian context that may affect its biology and the global distribution, as reported in the literature. A continuously progressive increase in occurrence was evident, but the rapid rise observed in the current decade was alarming. The world map of juvenile nasopharyngeal angiofibroma incidence does not reflect true global distribution given the paucity of reporting. Our centre has dealt with approximately 400 cases in the last 24 years. With the alarming increase in juvenile nasopharyngeal angiofibroma incidence, there is a need for a registry to define its epidemiology. The world literature needs to reflect the status of juvenile nasopharyngeal angiofibroma incidence in the third world as well. Environmental factors known for hormone disruptive actions may influence its occurrence. Such aspects need to be considered to plan specific prevention policies.

Shell damage and shell repair in the Antarctic limpet Nacella concinna from King George Island

NASA Astrophysics Data System (ADS)

Cadée, Gerhard C.

1999-03-01

Nacella concinna is the most conspicuous macroinvertebrate in the intertidal of King George Island. An important predator, the Kelp gull Larus dominicanus, feeds on Nacella during spring low tides. The gulls deposit empty Nacella shells as regurgitates mainly on roosts on coastal rocks. The regurgitates were found to consist of 40% shell fragments by weight and 60% intact shells. Faeces of Kelp gulls contained much smaller fragments than the regurgitates. Some of the Nacella, particularly those too large to ingest, are handled in the intertidal. The middens are, therefore, inadequate to study size selection by Kelp gulls: the largest Nacella are underrepresented. Seventy-five per cent of the intact Nacella shells from the Larus middens showed one or more shell repairs. Such repairs may be due to unsuccessful attacks by gulls, but more probably they indicate damage caused by rolling ice blocks and stones in the intertidal and shallow subtidal. A number of living Nacella were found stranded on the beach, detached from the rocks. They showed damage along the shell margin and even one Nacella was collected without any shell left. The observed repair frequency of 75% in Nacella was much higher than in other (smaller) intertidal gastropods at Potter Peninsula (3-11%, av. 8%). Comparably high frequencies are observed for instance in tropical intertidal gastropods, where repair is due to heavy unsuccessful crab predation; however, shell-crushing crabs are absent on King George Island. This indicates that palaeontologists should be cautious in ascribing all shell repairs in fossil shells (particularly from tidal environments) to predators. Shell repair in the related Nacella deaurata, collected in a less exposed site at Port Stanley (Falkland Islands), occurred only in 13% of the specimens. Another conspicuous form of shell damage was due to grazing by Nacella on the boring algae living in other Nacella shells. Epigrowth of crustose calcareous algae inhibited such grazing

Capital Drag: kinging in Washington, DC.

PubMed

Patterson, Jennifer Lyn

2002-01-01

Through individual interviews with three DC drag kings and detailed, first-person accounts of their performances, I examine the role the kings play within the lesbian community at Club Chaos in Dupont Circle. My interviews address how and why the kings started performing, how their drag characters relate to their everyday personalities and experiences as lesbian women, why performing in drag is important to them, why drag performances are important to the women who attend their shows, and how gay men and drag queens have responded to their performances. My descriptions of the kings' performances, the audience response, and the atmosphere they create at the club reflect my viewpoint as a lesbian audience participant who has much appreciation for drag queens and much curiosity about the burgeoning drag king scene. I conclude that drag kings provide a valuable service to lesbian communities by creating a safe, supportive environment in which lesbian performers and audience members can celebrate and explore their relationships to female masculinities and queer sexualities.

Geographic Variation in Camouflage Specialization by a Decorator Crab.

PubMed

Stachowicz, John J; Hay, Mark E

2000-07-01

In North Carolina, the decorator crab Libinia dubia camouflages almost exclusively with the chemically noxious alga Dictyota menstrualis. By placing this alga on its carapace, the crab behaviorally sequesters the defensive chemicals of the plant and gains protection from omnivorous consumers. However, Dictyota is absent north of North Carolina, whereas Libinia occurs as far north as New England. Crabs from three northern locations where Dictyota is absent (Rhode Island, Connecticut, and New Jersey) camouflaged to match their environment, rather than selectively accumulating any one species. When D. menstrualis was offered to crabs from northern sites, they did not distinguish between it and other seaweeds for camouflage, whereas crabs from Alabama and two locations in North Carolina used D. menstrualis almost exclusively. In addition, in winter and spring, when Dictyota was seasonally absent in North Carolina, Libinia selectively camouflaged with the sun sponge Hymeniacidon heliophila, which was chemically unpalatable to local fishes. Thus, southern crabs were consistent specialists on chemically defended species for camouflage, while northern crabs were more generalized. The geographic shift in crab behavior away from specialization coincides with a reported decrease in both total predation pressure and the frequency of omnivorous consumers. These shifts in the nature and intensity of predation pressure may favor different camouflage strategies (generalist vs. specialist), contributing to the observed geographic differences in camouflage behavior.

(1)H NMR metabolomic profiling of the blue crab (Callinectes sapidus) from the Adriatic Sea (SE Italy): A comparison with warty crab (Eriphia verrucosa), and edible crab (Cancer pagurus).

PubMed

Zotti, Maurizio; De Pascali, Sandra Angelica; Del Coco, Laura; Migoni, Danilo; Carrozzo, Leonardo; Mancinelli, Giorgio; Fanizzi, Francesco Paolo

2016-04-01

The metabolomic profile of blue crab (Callinectes sapidus) captured in the Acquatina lagoon (SE Italy) was compared to an autochthonous (Eriphia verrucosa) and to a commercial crab species (Cancer pagurus). Both lipid and aqueous extracts of raw claw muscle were analyzed by (1)H NMR spectroscopy and MVA (multivariate data analysis). Aqueous extracts were characterized by a higher inter-specific discriminating power compared to lipid fractions. Specifically, higher levels of glutamate, alanine and glycine characterized the aqueous extract of C. sapidus, while homarine, lactate, betaine and taurine characterized E. verrucosa and C. pagurus. On the other hand, only the signals of monounsaturated fatty acids distinguished the lipid profiles of the three crab species. These results support the commercial exploitation and the integration of the blue crab in human diet of European countries as an healthy and valuable seafood. Copyright © 2015 Elsevier Ltd. All rights reserved.

Critical habitat for ovigerous Dungeness crabs

USGS Publications Warehouse

Scheding, Karen; Shirley, Thomas C.; O'Clair, Charles E.; Taggart, S. James; Kruse, Gordon H.; Bez, Nicolas; Booth, Anthony; Dorn, Martin W.; Hills, Susan; Lipcius, Romuald N.; Pelletier, Dominique; Roy, Claude; Smith, Stephen J.; Witherell, David B.

2001-01-01

The Dungeness crab, Cancer magister, supports an important fishery in the northeastern Pacific Ocean, yet there is limited knowledge of ovigerous female brooding locations and brooding behavior. Our earlier research suggests that ovigerous crabs aggregate at the same brooding locations for many years. Within these locations, ovigerous females occur in high densities, with the majority of the aggregation buried within the sediment. These locations often have similar water depths and sediment types and appear to be critical for this life history stage. Our study was designed to examine the bathymetric distribution of Dungeness crabs in bays with and without sea otters at eight locations within the Glacier Bay area by conducting transects with a video-equipped manned submersible. Two of the bays investigated contained large aggregations of ovigerous females. At both sites the substrate was composed primarily of sand. However, only a small percentage of the 33 km of transects were classified as sand. These data suggest that sand substrate may be a limiting resource. Since crab brooding aggregations represent a large portion of the crab population within a small area, and because they are a critical component of Dungeness life history, areas with these characteristics need to be investigated, mapped, and protected from development or exploitation. The areas requiring protection from the impact of anthropogenic wastes, fishing, and logging activities could be quite small, thus limiting conflict with alternative users.

NASA Administrator Speaks at Martin Luther King, Jr. Commemorati

NASA Image and Video Library

2012-01-16

NASA Administrator Charles Bolden, right, joins in a group portrait with the niece of Martin Luther King, Jr., Alveda King, far left, Father Frank Pavone, wife of Martin Luther King, Jr's brother, Mrs. Naomi Barber King, Dr. Cameron Alexander, Dr. Frederick D. Haynes III, daughter of Martin Luther King, Jr., Dr. Bernice A. King, Kasim Reed, Mayor of Atlanta, Dr. Christine King Farris, Martin Luther King, Jr's sister, and Ms. Raj Razdan shortly after the 44th annual Martin Luther King, Jr. Commemorative Service on Monday, Jan. 16, 2012 at Ebenezer Baptist Church in Atlanta. Photo Credit: (NASA/Bill Ingalls)

Most Detailed Image of the Crab Nebula

NASA Image and Video Library

2005-12-01

The Crab Nebula is one of the most intricately structured and highly dynamical objects ever observed. The new Hubble image of the Crab was assembled from 24 individual exposures taken with the NASA/ESA Hubble Space Telescope

Nectonema zealandica n. sp. (Nematomorpha: Nectonematoidea) parasitising the purple rock crab Hemigrapsus edwardsi (Brachyura: Decapoda) in New Zealand, with notes on the prevalence of infection and host defence reactions.

PubMed

Poinar, G; Brockerhoff, A M

2001-10-01

A new species of marine hairworm, Nectonema zealandica (Nematomorpha: Nectonematoidea), is described from the purple rock crab Hemigrapsus edwardsi Hilgendorf from the South Island, New Zealand. This is the first record of Nectonema in the South Pacific Ocean and the southernmost locality for the genus. The description is based on juveniles and pre-adults taken from crabs. The new species is characterised by its stomal structure, presence of four cephalic papillae, mesenchyme arranged in eight lobes in pre-adults, insertion of muscle layer increasing body diameter at the septum and translucent anterior chamber. Data on the prevalence of infection over a three-year period, rates of parasitism in relation to host sex and size, and host defence reactions are presented. A list of all reported hosts of nectonematids is included.

50 CFR 680.6 - Crab economic data report (EDR).

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Crab economic data report (EDR). 680.6... ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) SHELLFISH FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA General § 680.6 Crab economic data report (EDR). Persons participating in the CR crab fisheries are...

50 CFR 680.6 - Crab economic data report (EDR).

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Crab economic data report (EDR). 680.6... ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) SHELLFISH FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA General § 680.6 Crab economic data report (EDR). Persons participating in the CR crab fisheries are...

50 CFR 680.6 - Crab economic data report (EDR).

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 13 2012-10-01 2012-10-01 false Crab economic data report (EDR). 680.6... ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) SHELLFISH FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA General § 680.6 Crab economic data report (EDR). Persons participating in the CR crab fisheries are...

Ocean acidification impairs crab foraging behaviour.

PubMed

Dodd, Luke F; Grabowski, Jonathan H; Piehler, Michael F; Westfield, Isaac; Ries, Justin B

2015-07-07

Anthropogenic elevation of atmospheric CO2 is driving global-scale ocean acidification, which consequently influences calcification rates of many marine invertebrates and potentially alters their susceptibility to predation. Ocean acidification may also impair an organism's ability to process environmental and biological cues. These counteracting impacts make it challenging to predict how acidification will alter species interactions and community structure. To examine effects of acidification on consumptive and behavioural interactions between mud crabs (Panopeus herbstii) and oysters (Crassostrea virginica), oysters were reared with and without caged crabs for 71 days at three pCO2 levels. During subsequent predation trials, acidification reduced prey consumption, handling time and duration of unsuccessful predation attempt. These negative effects of ocean acidification on crab foraging behaviour more than offset any benefit to crabs resulting from a reduction in the net rate of oyster calcification. These findings reveal that efforts to evaluate how acidification will alter marine food webs should include quantifying impacts on both calcification rates and animal behaviour. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Coupled beam motion in a storage ring with crab cavities

DOE PAGES

Huang, Xiaobiao

2016-02-16

We studied the coupled beam motion in a storage ring between the transverse and longitudinal directions introduced by crab cavities. Analytic form of the linear decoupling transformation is derived. Also, the equilibrium bunch distribution in an electron storage ring with a crab cavity is given, including contribution to the eigen-emittance induced by the crab cavity. Furthermore, application to the short pulse generation scheme using crab cavities [1] is considered.

The King and I

ERIC Educational Resources Information Center

Gallagher, Mary Grace

2009-01-01

This year marks the 40th anniversary of the first Coretta Scott King Book Award, which encourages "the artistic expression of the black experience via literature and the graphic arts." The award, which began honoring illustrators in 1974, added the John Steptoe Award for New Talent in 1995. No doubt, past King award winners like Sharon Flake,…

Fiddler crabs (Uca spp.) as model hosts for laboratory infections of Hematodinium perezi.

PubMed

O'Leary, Patricia A; Shields, Jeffrey D

2017-02-01

The parasitic dinoflagellate, Hematodinium perezi, negatively impacts the commercially important blue crab, Callinectes sapidus. The parasite is a host generalist, but it has not been reported from littoral fiddler crabs living within a few meters of habitat known to harbor infected blue crabs. In the first study, populations of three species of fiddler crab were screened for natural infections. The infection status of field-collected and lab-inoculated crabs was determined by screening fresh hemolymph with a 0.3% neutral red solution. Fiddler crabs were collected by hand in an area adjacent to where infected blue crabs were commonly collected. None of the 431 fiddlers had natural infections. In two separate studies, three species of fiddler crabs, Uca minax, U. pugnax, and U. pugilator, were evaluated for their susceptibility to H. perezi via inoculation of trophic stages. Uca minax inoculated with 10,000 cells of H. perezi were monitored for progression of the parasite. During hemolymph screenings of disease progression, filamentous trophonts, ameboid trophonts, and clump colonies were observed, indicative of active infections. In the second study, the minimum infective dose in U. minax was investigated. Fiddler crabs were inoculated with 0, 100, 1000, or 10,000 cells per crab. The minimum dose was determined to be approximately 1000 ameboid trophonts per crab. All three species of fiddler crab were susceptible to H. perezi via inoculation. The parasite was serially transferred from fiddler crabs to blue crabs without loss of infectivity. Survival studies indicated similar progression patterns to those observed in blue crabs. Based on our results fiddler crabs can serve as a laboratory model for investigating H. perezi infections and may be useful for comparative studies with blue crabs. Copyright © 2016 Elsevier Inc. All rights reserved.

Preliminary survey of a nemertean crab egg predator, Carcinonemertes, on its host crab, Callinectes arcuatus (Decapoda, Portunidae) from Golfo de Nicoya, Pacific Costa Rica

PubMed Central

Okazaki, Robert K.; Wehrtmann, Ingo S.

2014-01-01

Abstract The possible presence of egg predators in brood masses of portunid crabs from Pacific Central America has not been studied yet. This survey reports the finding of a nemertean crab egg predator on the portunid crab, Callinectes arcuatus, from the Golfo de Nicoya, Pacific Costa Rica. Nemerteans were found in the egg masses of 26 out of the 74 crabs for a prevalence of 35%. The intensity (mean number of worms/ infected crab) was estimated to be 18 with a variance of 1–123 worms/infected crab. No nemerteans were observed either in the 19 Callinectes arcuatus from Golfo Dulce (southern Pacific coast) and the 10 Portunus asper from Herradura-Jaco (central Pacific coast). This nemertean is a member of the genus Carcinonemertes, which has been reported from the Caribbean coast of Panama. However, the encountered Carcinonemertes sp. is the first published finding and report from Costa Rica and Pacific Central America. PMID:25561848

A large bubble around the Crab Nebula

NASA Technical Reports Server (NTRS)

Romani, Roger W.; Reach, William T.; Koo, Bon Chul; Heiles, Carl

1990-01-01

IRAS and 21 cm observations of the interstellar medium around the Crab nebula show evidence of a large bubble surrounded by a partial shell. If located at the canonical 2 kpc distance of the Crab pulsar, the shell is estimated to have a radius of about 90 pc and to contain about 50,000 solar masses of swept-up gas. The way in which interior conditions of this bubble can have important implications for observations of the Crab are described, and the fashion in which presupernova evolution of the pulsar progenitor has affected its local environment is described.

Melatonin Promotes Cheliped Regeneration, Digestive Enzyme Function, and Immunity Following Autotomy in the Chinese Mitten Crab, Eriocheir sinensis

PubMed Central

Zhang, Cong; Yang, Xiao-zhen; Xu, Min-jie; Huang, Gen-yong; Zhang, Qian; Cheng, Yong-xu; He, Long; Ren, Hong-yu

2018-01-01

In the pond culture of juvenile Eriocheir sinensis, a high limb-impairment rate seriously affects the culture success. Therefore, it is particularly important to artificially promote limb regeneration. This study evaluated the effects of melatonin on cheliped regeneration, digestive ability, and immunity, as well as its relationship with the eyestalk. It was found that the injection of melatonin significantly increased the limb regeneration rate compared with the saline group (P < 0.05). The qRT-PCR results of growth-related genes showed that the level of EcR-mRNA (ecdysteroid receptor) and Chi-mRNA (chitinase) expression was significantly increased following the melatonin injection, while the expression of MIH-mRNA (molt-inhibiting hormone) was significantly decreased (P < 0.05). Melatonin significantly increased lipase activity (P < 0.05). We observed that the survival rates of limb-impaired and unilateral eyestalk-ablated crabs were substantially improved following melatonin treatment, whereas the survival of the unilateral eyestalk-ablated crabs was significantly decreased compared with the control group (P < 0.05). Furthermore, the results of serum immune and antioxidant capacity revealed that melatonin significantly increased the total hemocyte counts (THC), hemocyanin content, total antioxidant capacity (T-AOC), acid phosphatase (ACP), and glutathione peroxidase activity (GSH-Px), whereas the immune-related parameters were significantly decreased in eyestalk-ablated crabs (P < 0.05). Therefore, these findings indicate that melatonin exerts a protective effect on organism injury, which could promote limb regeneration by up-regulating the expression of growth-related genes, improve digestive enzyme activity, and strengthen the immune response, particularly antioxidant capacity. PMID:29623051

Mud crab ecology encourages site-specific approaches to fishery management

NASA Astrophysics Data System (ADS)

Dumas, P.; Léopold, M.; Frotté, L.; Peignon, C.

2012-01-01

Little is known about the effects of mud crabs population patterns on their exploitation. We used complementary approaches (experimental, fisher-based) to investigate how small-scale variations in density, size and sex-ratio related to the ecology of S. serrata may impact fishing practices in New Caledonia. Crabs were measured/sexed across 9 stations in contrasted mangrove systems between 2007 and 2009. Stations were described and classified in different kinds of mangrove forests (coastal, riverine, and estuarine); vegetation cover was qualitatively described at station scale. Annual catch was used as an indicator of fishing pressure. Middle-scale environmental factors (oceanic influence, vegetation cover) had significant contributions to crab density (GLM, 84.8% of variance), crab size and sex-ratio (< 30%). While small-scale natural factors contributed significantly to population structure, current fishing levels had no impacts on mud crabs. The observed, ecologically-driven heterogeneity of crab resource has strong social implications in the Pacific area, where land tenure system and traditional access rights prevent most fishers from freely selecting their harvest zones. This offers a great opportunity to encourage site-specific management of mud crab fisheries.

76 FR 30921 - South Atlantic Fishery Management Council; Public Meetings

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-27

... Committee; King and Spanish Mackerel Committee; Golden Crab Committee; Snapper Grouper Committee; Scientific... on ecosystem activities. 8. King and Spanish Mackerel Committee: June 13, 2011, 1:30 p.m. Until 3 p.m... a.m., the Council will receive a report from the King and Spanish Mackerel Committee, consider...

Identification of mud crab reovirus VP12 and its interaction with the voltage-dependent anion-selective channel protein of mud crab Scylla paramamosain.

PubMed

Xu, Hai-Dong; Su, Hong-Jun; Zou, Wei-Bin; Liu, Shan-Shan; Yan, Wen-Rui; Wang, Qian-Qian; Yuan, Li-Li; Chan, Siuming Francis; Yu, Xiao-Qiang; He, Jian-Guo; Weng, Shao-Ping

2015-05-01

Mud crab reovirus (MCRV) is the causative agent of a severe disease in cultured mud crab (Scylla paramamosain), which has caused huge economic losses in China. MCRV is a double-stranded RNA virus with 12 genomic segments. In this paper, SDS-PAGE, mass spectrometry and Western blot analyses revealed that the VP12 protein encoded by S12 gene is a structural protein of MCRV. Immune electron microscopy assay indicated that MCRV VP12 is a component of MCRV outer shell capsid. Yeast two hybrid cDNA library of mud crab was constructed and mud crab voltage-dependent anion-selective channel (mcVDAC) was obtained by MCRV VP12 screening. The full length of mcVDAC was 1180 bp with an open reading frame (ORF) of 849 bp encoding a 282 amino acid protein. The mcVDAC had a constitutive expression pattern in different tissues of mud crab. The interaction between MCRV VP12 and mcVDAC was determined by co-immunoprecipitation assay. The results of this study have provided an insight on the mechanisms of MCRV infection and the interactions between the virus and mud crab. Copyright © 2015 Elsevier Ltd. All rights reserved.

Martin Luther King, Jr. Teacher's Resource Manual.

ERIC Educational Resources Information Center

Connecticut State Dept. of Education, Hartford.

This Connecticut teachers' manual on Martin Luther King, Jr. includes: (1) teacher background information; (2) five excerpts from King's speeches; (3) four themes for lesson plans; and (4) sample lesson plans. The teacher's background information provides biographical sketches of King and his precursors. The five speeches reproduced here are…

Selective thoracic surgery in the Lenke type 1A: King III and King IV type curves.

PubMed

Parisini, P; Di Silvestre, M; Lolli, F; Bakaloudis, G

2009-06-01

Pedicle screw fixation enables enhanced three-dimensional correction of spinal deformities and effectively shortens the distal fusion level. However, the choice of distal fusion level is still controversial in single thoracic idiopathic scoliosis with the lumbar compensatory curve not crossing the middle line (Lenke type 1 with modifier A or King type III and IV curves).The authors retrospectively analyzed 31 patients treated by segmental pedicular instrumentation alone, affected by a single thoracic adolescent idiopathic scoliosis with a compensatory lumbar curve not crossing the midline (Lenke 1A), with an average age of 16.3 years (range 10-22 years). The patients with regard to the King classification were also assessed. A statistical analysis was performed to determine whether the two groups (King III, King IV) presented differences concerning the level of the stable vertebra (SV), end vertebra (EV), and neutral vertebra (NV) and were also analyzed the results at follow-up regarding the relationships between the SV, EV, and lowest instrumented vertebra (LIV). The statistical analysis showed a significant difference between the two curve types. In the King III type curve the SV, EV, and NV appeared to be more proximal than those of the King IV type curve and the segments between the SV, EV, and NV appeared to be reduced in King III curves compared with King IV curves. At a follow-up of 3.2 years (range 2.2-5) the thoracic curve showed a correction of 58.4% (from 62.3 degrees to 26.6 degrees ) and compensatory lumbar curve an average spontaneous correction of 52.4% (from 38.1 degrees to 18.1 degrees ).The position of the LIV was shorter than the position of the SV in 30 patients (97%) with an average "salvage" of 2.1 (from 1 to 4) distal fusion levels. Four cases (13%), all affected by a King IV type curve, presented at follow-up an unsatisfactory results due to an "adding on" phenomenon. The statistical analysis confirmed that this phenomenon was correlated

The surprising Crab pulsar and its nebula: a review.

PubMed

Bühler, R; Blandford, R

2014-06-01

The Crab nebula and its pulsar (referred to together as 'the Crab') have historically played a central role in astrophysics. True to this legacy, several unique discoveries have been made recently. The Crab was found to emit gamma-ray pulsations up to energies of 400 GeV, beyond what was previously expected from pulsars. Strong gamma-ray flares, of durations of a few days, were discovered from within the nebula, while the source was previously expected to be stable in flux on these time scales. Here we review these intriguing and suggestive developments. In this context we give an overview of the observational properties of the Crab and our current understanding of pulsars and their nebulae.

Particle beam and crabbing and deflecting structure

DOEpatents

Delayen, Jean [Yorktown, VA

2011-02-08

A new type of structure for the deflection and crabbing of particle bunches in particle accelerators comprising a number of parallel transverse electromagnetic (TEM)-resonant) lines operating in opposite phase from each other. Such a structure is significantly more compact than conventional crabbing cavities operating the transverse magnetic TM mode, thus allowing low frequency designs.

CHANGES IN THE CRAB PULSAR

NASA Technical Reports Server (NTRS)

2002-01-01

Scientists are learning more about how pulsars work by studying a series of Hubble Space Telescope images of the heart of the Crab Nebula. The images, taken over a period of several months, show that the Crab is a far more dynamic object than previously understood. At the center of the nebula lies the Crab Pulsar. The pulsar is a tiny object by astronomical standards -- only about six miles across -- but has a mass greater than that of the Sun and rotates at a rate of 30 times a second. As the pulsar spins its intense magnetic field whips around, acting like a sling shot, accelerating subatomic particles and sending them hurtling them into space at close to the speed of light. The tiny pulsar and its wind are the powerhouse for the entire Crab Nebula, which is 10 light-years across -- a feat comparable to an object the size of a hydrogen atom illuminating a volume of space a kilometer across. The three pictures shown here, taken from the series of Hubble images, show dramatic changes in the appearance of the central regions of the nebula. These include wisp-like structures that move outward away from the pulsar at half the speed of light, as well as a mysterious 'halo' which remains stationary, but grows brighter then fainter over time. Also seen are the effects of two polar jets that move out along the rotation axis of the pulsar. The most dynamic feature seen -- a small knot that 'dances around' so much that astronomers have been calling it a 'sprite' -- is actually a shock front (where fast-moving material runs into slower-moving material)in one of these polar jets. The telescope captured the images with the Wide Field and Planetary Camera 2 using a filter that passes light of wavelength around 550 nanometers, near the middle of the visible part of the spectrum. The Crab Nebula is located 7,000 light-years away in the constellation Taurus. Credit: Jeff Hester and Paul Scowen (Arizona State University), and NASA

The mangrove tree crab Aratus pisonii in a tropical estuarine coastal lagoon

NASA Astrophysics Data System (ADS)

Conde, Jesús Eloy; Díaz, Humberto

1989-06-01

The population dynamics and life history of the grapsid crab Aratus pisonii were studied during a 2 year span in mangroves of the Laguna de Tacarigua National Park, a Venezuelan estuarine coastal lagoon. Abundances of adult A. pisonii estimated by means of a catch-effort sampling scheme, were found similar for the three study sites, but varied through time apparently in relation to salinity. Females were significantly more abundant than males in a ratio of 1·61 to 1·00. Ovigerous females were continuously present during the study, fluctuating from 23·2% to 82·7% of the monthly capture. The percentage of ovigerous females was significantly higher during the fourth trimesters. The number of eggs per female increased as a linear function of carapace width, with a mean of 16 379 and extremes of 7 952 and 34 057. Juvenile crabs were present through the period of study, although their abundance was very low. Males grow bigger than females, which concentrate in intermediate size classes, possibly as a consequence of energy diversion towards reproduction. Carapace width (CW) and length (CL) showed an isometric relation for both sexes, with a high correlation ( r = 0·9914 for females, r = 0·9957 for males). Size (CW) frequency distribution was found to be more symmetrical for females than for males, and thus is appeared strongly skewed to the left. The estuarine population dynamics of A. pisonii is mainly determined by the rainy season, which brings about an increment of nutrients and productivity in the lagoon.

Kinging in Hungarian lesbian culture.

PubMed

Balogh, Andrea P

2011-01-01

This article looks at the position of the drag king in Hungarian lesbian culture. It focuses on Bandage, Socks and Facial Hair (2006), a documentary about a drag king workshop. The film documents the historical moment when the Hungarian workshop participants encounter the drag king as a lesbian tool for parodying and repoliticizing mainstream masculinity. I examine the ways in which the participants interpret their performances of masculinity and the film negotiates heteronormativity. I argue that the political merits of the film can be spelled out by reading the participants' (trans)gender politics from the perspective of the cultural specificities of post-socialist Hungary.

Land crabs as key drivers in tropical coastal forest recruitment

USGS Publications Warehouse

Lindquist, E.S.; Krauss, K.W.; Green, P.T.; O'Dowd, D. J.; Sherman, P.M.; Smith, T. J.

2009-01-01

Plant populations are regulated by a diverse assortment of abiotic and biotic factors that influence seed dispersal and viability, and seedling establishment and growth at the microsite. Rarely does one animal guild exert as significant an influence on different plant assemblages as land crabs. We review three tropical coastal ecosystems-mangroves, island maritime forests, and mainland coastal terrestrial forests-where land crabs directly influence forest composition by limiting tree establishment and recruitment. Land crabs differentially prey on seeds, propagules and seedlings along nutrient, chemical and physical environmental gradients. In all of these ecosystems, but especially mangroves, abiotic gradients are well studied, strong and influence plant species distributions. However, we suggest that crab predation has primacy over many of these environmental factors by acting as the first limiting factor of tropical tree recruitment to drive the potential structural and compositional organisation of coastal forests. We show that the influence of crabs varies relative to tidal gradient, shoreline distance, canopy position, time, season, tree species and fruiting periodicity. Crabs also facilitate forest growth and development through such activities as excavation of burrows, creation of soil mounds, aeration of soils, removal of leaf litter into burrows and creation of carbon-rich soil microhabitats. For all three systems, land crabs influence the distribution, density and size-class structure of tree populations. Indeed, crabs are among the major drivers of tree recruitment in tropical coastal forest ecosystems, and their conservation should be included in management plans of these forests. ?? 2009 Cambridge Philosophical Society.

The philosophical core of King's conceptual system.

PubMed

Whelton, B J

1999-04-01

Aristotelian understanding of being human is presented as the philosophical core of King's conceptual system. A summary of King's thought is organized according to contemporary influences. The article then turns to what Aristotle teaches about the composition of the world and what it means to be a human being. Wallace's life-powers model of the soul brings these insights into contemporary thought. Aristotelian philosophy completes King's account of the personal system by providing insight into what it is to be human. Parallels in the reasoning of transaction and Aristotelian deliberation are further evidence of classical influences within King's work.

Effects of coral bleaching on the obligate coral-dwelling crab Trapezia cymodoce

NASA Astrophysics Data System (ADS)

Stella, J. S.; Munday, P. L.; Jones, G. P.

2011-09-01

Corals are an essential and threatened habitat for a diverse range of reef-associated animals. Episodes of coral bleaching are predicted to increase in frequency and intensity over coming decades, yet the effects of coral-host bleaching on the associated animal communities remain poorly understood. The present study investigated the effects of host-colony bleaching on the obligate coral-dwelling crab, Trapezia cymodoce, during a natural bleaching event in the lagoon of Lizard Island, Australia. Branching corals, which harbour the highest diversity of coral associates, comprised 13% of live coral cover at the study site, with 83% affected by bleaching. Crabs on healthy and bleached colonies of Pocillopora damicornis were monitored over a 5-week period to determine whether coral bleaching affected crab density and movement patterns. All coral colonies initially contained one breeding pair of crabs. There was a significant decline in crab density on bleached corals after 5 weeks, with many corals losing one or both crabs, yet all healthy colonies retained a mating pair. Fecundity of crabs collected from bleached and healthy colonies of P. damicornis was also compared. The size of egg clutches of crabs collected from bleached hosts was 40% smaller than those from healthy hosts, indicating a significant reduction in fecundity. A laboratory experiment on movement patterns found that host-colony bleaching also prompted crabs to emigrate in search of more suitable colonies. Emigrant crabs engaged in aggressive interactions with occupants of healthy hosts, with larger crabs always usurping occupants of a smaller size. Decreased densities and clutch sizes, along with increased competitive interactions, could potentially result in a population decline of these important coral associates with cascading effects on coral health.

Profilicollis novaezelandensis n. sp. (Polymorphidae) and two other acanthocephalan parasites from shore birds (Haematopodidae and Scolopacidae) in New Zealand, with records of two species in intertidal crabs (Decapoda: Grapsidae and Ocypodidae).

PubMed

Brockerhoff, A M; Smales, L R

2002-05-01

Profilicollis novaezelandensis n. sp. (Acanthocephala: Polymorphidae) is described from the South Island pied oystercatcher Haematopus ostralegus finschi Martens (Haematopodidae) and the intertidal crab Hemigrapsus crenulatus (Milne Edwards) (Brachyura: Grapsidae) from the South Island of New Zealand. The new species can be distinguished from all the other species of the genus by a combination of the following characters: long neck (13% of total body length for adults) and a subspherical proboscis with 14-16 longitudinal rows of 7-8 hooks. The mud crabs Helice crassa Dana (Grapsidae) and Macrophthalmus hirtipes (Heller) (Ocypodidae) were also harbouring cystacanths and the bar-tailed godwit Limosa lapponica (Linnaeus) (Scolopacidae) juveniles of P. novaezelandensis. This is the first record of brachyuran decapods as intermediate hosts of Acanthocephala from New Zealand. P. antarcticus is recorded from three crab species (Helice crassa, Hemigraspus crenulatus and Macrophthalmus hirtipes) and two bird species (Haematopus o. finschi and Limosa lapponica) in New Zealand. An unidentified species of Plagiorhynchus was also found in two bird species (H. o. finschi and H. unicolor Forster). P. antarcticus and P. novaezelandensis are the first records of Profilicollis from New Zealand.

NREL Wins Martin Luther King Award

Science.gov Websites

the Martin Luther King, Jr. Business Social Responsibility Award for its support of minority and women Luther King, Jr. Business Social Responsibility Award will be presented during ceremonies at 11:45 a.m

Efficient monitoring of CRAB jobs at CMS

NASA Astrophysics Data System (ADS)

Silva, J. M. D.; Balcas, J.; Belforte, S.; Ciangottini, D.; Mascheroni, M.; Rupeika, E. A.; Ivanov, T. T.; Hernandez, J. M.; Vaandering, E.

2017-10-01

CRAB is a tool used for distributed analysis of CMS data. Users can submit sets of jobs with similar requirements (tasks) with a single request. CRAB uses a client-server architecture, where a lightweight client, a server, and ancillary services work together and are maintained by CMS operators at CERN. As with most complex software, good monitoring tools are crucial for efficient use and longterm maintainability. This work gives an overview of the monitoring tools developed to ensure the CRAB server and infrastructure are functional, help operators debug user problems, and minimize overhead and operating cost. This work also illustrates the design choices and gives a report on our experience with the tools we developed and the external ones we used.

Efficient Monitoring of CRAB Jobs at CMS

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

Silva, J. M.D.; Balcas, J.; Belforte, S.

CRAB is a tool used for distributed analysis of CMS data. Users can submit sets of jobs with similar requirements (tasks) with a single request. CRAB uses a client-server architecture, where a lightweight client, a server, and ancillary services work together and are maintained by CMS operators at CERN. As with most complex software, good monitoring tools are crucial for efficient use and longterm maintainability. This work gives an overview of the monitoring tools developed to ensure the CRAB server and infrastructure are functional, help operators debug user problems, and minimize overhead and operating cost. This work also illustrates themore » design choices and gives a report on our experience with the tools we developed and the external ones we used.« less

Resources Management Strategy For Mud Crabs (Scylla spp.) In Pemalang Regency

NASA Astrophysics Data System (ADS)

Purnama Fitri, Aristi Dian; Boesono, Herry; Sabdono, Agus; Adlina, Nadia

2017-02-01

The aim of this research is to develop resources management strategies of mud crab (Scylla spp.) in Pemalang Regency. The method used is descriptive survey in a case study. This research used primary data and secondary data. Primary data were collected through field observations and in-depth interviews with key stakeholders. Secondary data were collected from related publications and documents issued by the competent institutions. SWOT Analysis was used to inventory the strengths, weaknesses, opportunities and threats. TOWS matrix was used to develop an alternative of resources management strategies. SWOT analysis was obtained by 6 alternative strategies that can be applied for optimization of fisheries development in Pemalang Regency. The strategies is the control of mud crab fishing gear, restricted size allowable in mud crab, control of mud crab fishing season, catch monitoring of mud crab, needs a management institutions which ensure the implementation of the regulation, and implementation for mud crab aquaculture. Each alternative strategy can be synergized to optimize the resources development in Pemalang Regency.

The use of artificial crabs for testing predatory behavior and health in the octopus.

PubMed

Amodio, Piero; Andrews, Paul; Salemme, Marinella; Ponte, Giovanna; Fiorito, Graziano

2014-01-01

The willingness of the cephalopod mollusc Octopus vulgaris to attack a live crab is traditionally used as a method to assess the overall health and welfare of octopuses in the laboratory. This method requires placing a crab in the home tank of an animal, measuring the time (latency) taken for the octopus to initiate an attack and withdrawing the crab immediately prior to capture. The same crab is commonly used to assess multiple octopuses as part of daily welfare assessment. Growing concern for the welfare of crustaceans and a review of all laboratory practices for the care and welfare of cephalopods following the inclusion of this taxon in 2010/63/EU prompted a study of the utility of an artificial crab to replace a live crab in the assessment of octopus health. On consecutive days O. vulgaris (N=21) were presented with a live, a dead or an artificial crab, and the latency to attack measured. Despite differences in the predatory performance towards the three different crab alternatives, octopuses readily attacked the artificial (and the dead) crab, showing that they can generalize and respond appropriately towards artificial prey. Researchers should consider using an artificial crab to replace the use of a live crab as part of the routine health assessment of O. vulgaris.

Science support for evaluating natural recovery of polychlorinated biphenyl concentrations in fish from Crab Orchard Lake, Crab Orchard National Wildlife Refuge, Illinois

USGS Publications Warehouse

Kunz, Bethany K.; Hinck, Jo E.; Calfee, Robin D.; Linder, Greg L.; Little, Edward E.

2018-05-11

IntroductionCrab Orchard Lake in southern Illinois is one of the largest and most popular recreational lakes in the state. Construction of the nearly 7,000-acre reservoir in the late 1930s created employment opportunities through the Works Progress Administration, and the lake itself was intended to supply water, control flooding, and provide recreational opportunities for local communities (Stall, 1954). In 1942, the Department of War appropriated or purchased more than 20,000 acres of land around Crab Orchard Lake and constructed the Illinois Ordnance Plant, which manufactured bombs and anti-tank mines during World War II. After the war, an Act of Congress transferred the property to the U.S. Department of the Interior. Crab Orchard National Wildlife Refuge was established on August 5, 1947, for the joint purposes of wildlife conservation, agriculture, recreation, and industry. Production of explosives continued, but new industries also moved onsite. More than 200 tenants have held leases with Crab Orchard National Wildlife Refuge and have operated a variety of manufacturing plants (electrical components, plated metal parts, ink, machined parts, painted products, and boats) on-site. Soils, water, and sediments in several areas of the refuge were contaminated with hazardous substances from handling and disposal methods that are no longer acceptable environmental practice (for example, direct discharge to surface water, use of unlined landfills).Polychlorinated biphenyl (PCB) contamination at the refuge was identified in the 1970s, and a PCB-based fish-consumption advisory has been in effect since 1988 for Crab Orchard Lake. The present advisory covers common carp (Cyprinus carpio) and channel catfish (Ictalurus punctatus); see Illinois Department of Public Health (2017). Some of the most contaminated areas of the refuge were actively remediated, and natural ecosystem recovery processes are expected to further reduce residual PCB concentrations in the lake. The U

Comparative brain architecture of the European shore crab Carcinus maenas (Brachyura) and the common hermit crab Pagurus bernhardus (Anomura) with notes on other marine hermit crabs.

PubMed

Krieger, Jakob; Sombke, Andy; Seefluth, Florian; Kenning, Matthes; Hansson, Bill S; Harzsch, Steffen

2012-04-01

The European shore crab Carcinus maenas and the common hermit crab Pagurus bernhardus are members of the sister taxa Brachyura and Anomura (together forming the taxon Meiura) respectively. Both species share similar coastal marine habitats and thus are confronted with similar environmental conditions. This study sets out to explore variations of general brain architecture of species that live in seemingly similar habitats but belong to different major malacostracan taxa and to understand possible differences of sensory systems and related brain compartments. We examined the brains of Carcinus maenas, Pagurus bernhardus, and three other hermit crab species with immunohistochemistry against tyrosinated tubulin, f-actin, synaptic proteins, RF-amides and allatostatin. Our comparison showed that their optic neuropils within the eyestalks display strong resemblance in gross morphology as well as in detailed organization, suggesting a rather similar potential of processing visual input. Besides the well-developed visual system, the olfactory neuropils are distinct components in the brain of both C. maenas and P. bernhardus as well as the other hermit crabs, suggesting that close integration of olfactory and visual information may be useful in turbid marine environments with low visibility, as is typical for many habitats such as, e.g., the Baltic and the North Sea. Comparing the shape of the olfactory glomeruli in the anomurans showed some variations, ranging from a wedge shape to an elongate morphology. Furthermore, the tritocerebrum and the organization of the second antennae associated with the tritocerebrum seem to differ markedly in C. maenas and P. bernhardus, indicating better mechanosensory abilities in the latter close to those of other Decapoda with long second antennae, such as Astacida, Homarida, or Achelata. This aspect may also represent an adaptation to the "hermit lifestyle" in which competition for shells is a major aspect of their life history. The shore

Comparison of automated BAX polymerase chain reaction and standard culture methods for detection of Listeria monocyogenes in blue crab meat (Callinectus sapidus) and blue crab processing plants

USDA-ARS?s Scientific Manuscript database

This study compared the BAX Polymerase Chain Reaction method (BAX PCR) with the Standard Culture Method (SCM) for detection of L. monocytogenes in blue crab meat and crab processing plants. The aim of this study was to address this data gap. Raw crabs, finished products and environmental sponge samp...

50 CFR 648.262 - Effort-control program for red crab limited access vessels.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Effort-control program for red crab... UNITED STATES Management Measures for the Atlantic Deep-Sea Red Crab Fishery § 648.262 Effort-control program for red crab limited access vessels. (a) General. A vessel issued a limited access red crab permit...

78 FR 40696 - Proposed Information Collection; Comment Request; Alaska Crab Cost Recovery

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-08

... Collection; Comment Request; Alaska Crab Cost Recovery AGENCY: National Oceanic and Atmospheric..., a limited access system that allocates BSAI Crab resources among harvesters, processors, and coastal communities. The intent of the Alaska Crab Cost Recovery is to [[Page 40697

Drag king magic: performing/becoming the other.

PubMed

Rosenfeld, Kathryn

2002-01-01

This chapter seeks to theorize drag king practice through the lenses of alterity, liminality, and performance theory, while attempting to complicate and reinvigorate discussions of identity raised by drag. I examine the ways in which drag king performance plumbs the concept of "the Other," and forces confrontation with a complex field of desire. Contemporary "queergirl" existence negotiates a range of desirable and desiring Others, from the polarities (i.e., butch-femme) unique to queer structures of desire, to the desire of those on the cultural margins for the power of those at the center, and vice versa. I employ anthropological theories of performance, mimesis, and liminality to establish a framework through which drag kings may be viewed as crucibles of this desire and agents of this power exchange. By performing maleness, drag kings expand and redraw the definitional boundaries of the male, interfere with the cultural power of mainstream maleness, and simultaneously transfer some of this power to themselves as queer women. At the same time, drag king existence forces a renegotiation of queergirl desire to encompass a range of masculinities. By performing/becoming the Other, drag kings engage in a practice of magic which transforms both margin and center.

Epizootiology of the parasitic dinoflagellate Hematodinium sp. in the American blue crab Callinectes sapidus.

PubMed

Messick, G A; Shields, J D

2000-11-14

Hematodinium sp. is a parasitic dinoflagellate that infects and kills blue crabs Callinectes sapidus. Periodic outbreaks of dinoflagellate infections with subsequent high host mortalities prompted a study of the epizootiology and distribution of the crab pathogen. Hemolymph samples from over 13000 crabs were assessed for infections over 8 yr. Moderate to high prevalences were found at several locations along the Atlantic and Gulf coasts of the United States. In the coastal bays of Maryland and Virginia, prevalence followed a seasonal pattern, with a sharp peak in late autumn. Infections were significantly more prevalent in crabs measuring less than 30 mm carapace width; host sex did not influence prevalence. Prevalences were highest in crabs collected from salinities of 26 to 30%o; no infected crabs were found in salinities below 11%o. Intensity of infection did not vary among crab sizes, molt stages, or sexes. Naturally and experimentally infected crabs died over 35 and 55 d in captivity, with a mean time to death of approximately 13 and 42 d, respectively. Several other crustaceans, including gammaridean amphipods, xanthid (mud) crabs, and the green crab Carcinus maenus, were found with Hematodinium-like infections. Considering its widespread distribution and high pathogenicity, we suggest that Hematodinium sp. represents a significant threat to blue crab populations in high salinity estuaries along the Atlantic and Gulf coasts of the USA.

Feeding behaviour: hydrothermal vent crabs feast on sea 'snow'.

PubMed

Jeng, M-S; Ng, N K; Ng, P K L

2004-12-23

The crab Xenograpsus testudinatus lives at enormously high densities around the sulphur-rich hydrothermal vents found in shallow waters off Taiwan, even though this acidic environment is low in nutrients. Here we show that these crabs swarm out of their crevices at slack water and feed on the vast numbers of zooplankton that are killed by the vents' sulphurous plumes, and that rain down like marine 'snow'. This opportunistic feeding behaviour explains how the crabs are able to survive in the adverse toxic environment of these shallow hydrothermal vents.

Characterization of the complete mitochondrial genome of the king pigeon (Columba livia breed king).

PubMed

Zhang, Rui-Hua; He, Wen-Xiao; Xu, Tong

2015-06-01

The king pigeon is a breed of pigeon developed over many years of selective breeding primarily as a utility breed. In the present work, we report the complete mitochondrial genome sequence of king pigeon for the first time. The total length of the mitogenome was 17,221 bp with the base composition of 30.14% for A, 24.05% for T, 31.82% for C, and 13.99% for G and an A-T (54.22 %)-rich feature was detected. It harbored 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and one non-coding control region (D-loop region). The arrangement of all genes was identical to the typical mitochondrial genomes of pigeon. The complete mitochondrial genome sequence of king pigeon would serve as an important data set of the germplasm resources for further study.

Gender and snow crab occupational asthma in Newfoundland and Labrador, Canada.

PubMed

Howse, Dana; Gautrin, Denyse; Neis, Barbara; Cartier, André; Horth-Susin, Lise; Jong, Michael; Swanson, Mark C

2006-06-01

Fish and shellfish processing employs many thousands of people globally, with shellfish processing becoming more important in recent years. Shellfish processing is associated with multiple occupational health and safety (OHS) risks. Snow crab occupational asthma (OA) is work-related asthma associated with processing snow crab. We present a gender analysis of findings from a 3-year multifaceted study of snow crab OA in Newfoundland and Labrador, Canada. The study was carried out in four snow crab processing communities between 2001 and 2004. An anonymous survey questionnaire on knowledge, beliefs, and concerns related to processing snow crab administered to 158 workers attending community meetings at the start of the research found that women were significantly more likely than men to associate certain health problems, especially chest tightness, difficulty breathing, and cough, with crab processing (P<0.001). Worker health assessments carried out with 215 processing workers (187 current/28 former; 120 female/95 male) found that female participants were more likely to be diagnosed as almost certain/highly probable snow crab OA and allergy (P=0.001) and to be sensitized to snow crab (P=0.01) than male participants. Work histories from the health assessments were used to classify processing jobs as male or female. Allergen sampling (211 allergen samples: 115 area, 96 personal breathing zone) indicated that the plant areas where these male jobs were concentrated were associated with lower levels of aerosolized crab allergens (the agents responsible for OA to snow crab) than areas associated with female jobs. This difference was statistically significant in the two plants with poor ventilation (p<0.001 and P=0.017 for these plants). A gender analysis of work history data showed that female health assessment participants were likely to have worked longer processing snow crab than males (5 years versus 3.5 years, respectively). Cross-referencing of work history results

Evolutionary history of true crabs (Crustacea: Decapoda: Brachyura) and the origin of freshwater crabs.

PubMed

Tsang, Ling Ming; Schubart, Christoph D; Ahyong, Shane T; Lai, Joelle C Y; Au, Eugene Y C; Chan, Tin-Yam; Ng, Peter K L; Chu, Ka Hou

2014-05-01

Crabs of the infra-order Brachyura are one of the most diverse groups of crustaceans with approximately 7,000 described species in 98 families, occurring in marine, freshwater, and terrestrial habitats. The relationships among the brachyuran families are poorly understood due to the high morphological complexity of the group. Here, we reconstruct the most comprehensive phylogeny of Brachyura to date using sequence data of six nuclear protein-coding genes and two mitochondrial rRNA genes from more than 140 species belonging to 58 families. The gene tree confirms that the "Podotremata," are paraphyletic. Within the monophyletic Eubrachyura, the reciprocal monophyly of the two subsections, Heterotremata and Thoracotremata, is supported. Monophyly of many superfamilies, however, is not recovered, indicating the prevalence of morphological convergence and the need for further taxonomic studies. Freshwater crabs were derived early in the evolution of Eubrachyura and are shown to have at least two independent origins. Bayesian relaxed molecular methods estimate that freshwater crabs separated from their closest marine sister taxa ~135 Ma, that is, after the break up of Pangaea (∼200 Ma) and that a Gondwanan origin of these freshwater representatives is untenable. Most extant families and superfamilies arose during the late Cretaceous and early Tertiary.

Heavy metals in red crabs, Chaceon quinquedens, from the Gulf of Mexico.

PubMed

Perry, Harriet; Isphording, Wayne; Trigg, Christine; Riedel, Ralf

2015-12-30

The red crab, Chaceon quinquedens, is distributed in deep waters of the Gulf of Mexico (GOM) and is most abundant in an area associated with sediment deposition from the Mississippi River. Sediment geochemistry and biological and ecological traits of red crabs favor accumulation of contaminants. Red crabs, sediment, and bottom water samples were taken from three distinct geographic locations representing areas with differing exposure to contaminant laden effluents from the Mississippi River. Inductively coupled plasma spectrophotometry and atomic absorption spectrophotometry were employed to determine levels of heavy metals in red crab muscle tissue. Ion site partitioning was used to determine metal speciation in sediments. Red crabs showed evidence of heavy metal bioaccumulation in all sample areas with high variability in contaminant levels in individual crabs for some metals. Bioavailability of metals in sediment did not always result in accumulation in muscle tissue. Copyright © 2015 Elsevier Ltd. All rights reserved.

Population and reproductive biology of the fiddler crab Uca thayeri Rathbun, 1900 (Crustacea: Ocypodidae) in a tropical mangrove from Northeast Brazil

NASA Astrophysics Data System (ADS)

Arruda Bezerra, Luis Ernesto; Matthews-Cascon, Helena

2007-05-01

Population and reproductive biology of Uca thayeri Rathbun, 1900 were studied for the first time in a tropical mangrove. Absolute density, sex ratio, population structure, handedness, breeding season and fecundity were investigated. Seven transects were delimited in a mangrove area of the Pacoti River, Northeast of Brazil (3° 43' 02″ S/38° 32' 35″ W). On each transect, ten 0.25 m 2 squares were sampled on a monthly basis during low tide periods from September 2003 to August 2004. A total of 483 crabs were obtained, of which 250 were males, 219 non-ovigerous females, and 14 ovigerous females. The U. thayeri population presented bi-modal size frequency distribution, with males and non-ovigerous females not differing significantly size-wise. Ovigerous females were larger than males and non-ovigerous females. The overall sex ratio (1:1.07) did not differ significantly from the expected 1:1 proportion. The major cheliped was the right one in 50% of the males. The observed density was of 8.5 individuals/m 2, with the specimens being found mostly in shaded areas. Ovigerous females were found in 5 months of the year, coinciding with the rainy season, suggesting that the population of U. thayeri presents seasonal reproductive events. Juvenile crabs were more abundant during the dry period, while larger crabs were found mainly during the rainy period. The fecundity of the studied population was much smaller than that of subtropical populations of this species. The regression analysis shows that the number of eggs increases linearly with the increase of carapace width.

The effects of fipronil and the photodegradation product fipronil desulfinyl on growth and gene expression in juvenile blue crabs, Callinectes sapidus, at different salinities

USGS Publications Warehouse

Goff, Andrew D.; Saranjampour, Parichehr; Ryan, Lauren M.; Hladik, Michelle; Covi, Joseph A.; Armbrust, Kevin L.; Brander, Susanne M.

2017-01-01

Endocrine disrupting compounds (EDCs) are now widely established to be present in the environment at concentrations capable of affecting wild organisms. Although many studies have been conducted in fish, less is known about effects in invertebrates such as decapod crustaceans. Decapods are exposed to low concentrations of EDCs that may cause infertility, decreased growth, and developmental abnormalities. The objective herein was to evaluate effects of fipronil and its photodegradation product fipronil desulfinyl. Fipronil desulfinyl was detected in the eggs of the decapod Callinectes sapidus sampled off the coast of South Carolina. As such, to examine specific effects on C. sapidus exposed in early life, we exposed laboratory-reared juveniles to fipronil and fipronil desulfinyl for 96 hours at three nominal concentrations (0.01, 0.1, 0.5 μg/L) and two different salinities (10, 30 ppt). The size of individual crabs (weight, carapace width) and the expression of several genes critical to growth and reproduction were evaluated. Exposure to fipronil and fipronil desulfinyl resulted in significant size increases in all treatments compared to controls. Levels of expression for vitellogenin (Vtg), an egg yolk precursor, and the ecdysone receptor (EcR), which binds to ecdysteroids that control molting, were inversely correlated with increasing fipronil and fipronil desulfinyl concentrations. Effects on overall growth and on the expression of EcR and Vtg differ depending on the exposure salinity. The solubility of fipronil is demonstrated to decrease considerably at higher salinities. This suggests that fipronil and its photodegradation products may be more bioavailable to benthic organisms as salinity increases, as more chemical would partition to tissues. Our findings suggest that endocrine disruption is occurring through alterations to gene expression in C. sapidus populations exposed to environmental levels of fipronil, and that effects may be dependent upon the

Effects of Freshwater Discharge in Sandy Beach Populations: The Mole Crab Emerita brasiliensis in Uruguay

NASA Astrophysics Data System (ADS)

Lercari, D.; Defeo, O.

1999-10-01

Sandy beaches are ecosystems which are heavily affected by human activities. An example of this is freshwater discharges, which are known to change salinity, temperature and nutrient regimes and degrade nearshore environments. However, the effects of this kind of disturbance on sandy beach fauna have been little studied. This paper reports the spatial effects of a man-made freshwater canal discharge on the population structure, abundance and reproductive characteristics of the sandy beach mole crab Emerita brasiliensis. Along the 22 km of sandy beach sampled, the mole crab showed a marked longshore variability in population structure and abundance. Abundance of different population components (juveniles, males, females and ovigerous females) significantly decreased towards the canal. Population structure by sex and size, individual weight, fecundity and female maturity patterns at size also displayed a non-linear response to the distance from the freshwater discharge. Only the size structure of males did not follow this pattern. For males, spatial heterogeneity enhanced the detection of density-dependence at less disturbed sites. The authors conclude that artificial freshwater discharges could significantly influence the distribution, abundance and life-history traits of the biota of sandy beaches, and that further study of these ecosystems should include human activities as important factors affecting spatial and temporal trends. The need to consider different spatial and temporal scales in order to detect the effect of anthropogenically-driven impacts in sandy beach populations is stressed.

Sulfur and Oxygen Isotopic Composition of Sulfate in the Fresh Water, King Sejong Station, King George Island, Antarctica

NASA Astrophysics Data System (ADS)

Kim, M.; Lee, I.; Lee, J.; Park, B.; Mayer, B.; Kaufman, A. J.; Park, S.; Kim, G.; Lee, K.

2008-12-01

Isotopic compositions of sulfur (δ34S) and oxygen (δ18O) were measured for the sulfate of the fresh water near the King Sejong Station, King George Island, Antarctica. Sejong station is located in the Barton peninsular of the King George Island. The geology around King Sejong station mainly composed of basalt-andesite, quart monzodiorite, and granodiorite. Lapilli tuff, conglomerate, sandstone, and siltstone occur along the southern and eastern shore of the Barton peninsula. Lapilli tuff also occurs on the highland located on southeastern part of the Barton peninsula. The δ34S values of sulfate extracted from fresh water samples at King Sejong Station range from 13.7 to 16.3 per mil excluding 1 sample. These sulfur values are very narrow in their range compared with those from anthropogenic sources. These sulfur values are 5 to 7 per mil lower than those of typical present seawater. Considering the rocks occurring near the King Sejong station, these sulfur isotopic values do not seem to be related to any evaporites of certain age. In Antarctic region the natural source of sulfate dissolved in water could be originated from marine biogenic source (DMS), sea-salt, volcanic source, or other continental sources. Most of the δ34S values of sulfate at King Sejong station seems to indicate the dominance of marine biogenic origin for the source of sulfur. The δ18O values of sulfate extracted from fresh water samples at King Sejong Station range from 1.9 to 6.4 per mil excluding 1 sample. These oxygen isotope values are lower than those of the sulfate in the present seawater by 6 per mil. However, both sulfur and oxygen isotope values strongly represent the influence of the seawater sulfate. One sample have 2.6 and -1.1 per mil in its δ34S and δ18O values, respectively, that are quite different from the isotopic values of other samples. This sample was collected in the highland far from the King Sejong station. Therefore this sample might reflect the composition of

Beyond the CRAB symptoms: a study of presenting clinical manifestations of multiple myeloma.

PubMed

Talamo, Giampaolo; Farooq, Umar; Zangari, Maurizio; Liao, Jason; Dolloff, Nathan G; Loughran, Thomas P; Epner, Elliot

2010-12-01

Although the typical clinical manifestations of multiple myeloma (MM) are summarized by the CRAB symptoms (hypercalcemia, renal insufficiency, anemia, and bone lesions), a significant proportion of patients with MM present with a variety of other clinical manifestations. We conducted a study evaluating the presenting symptoms that led to the diagnosis of MM. We conducted a retrospective review of 170 consecutive patients with MM seen at the Penn State Hershey Cancer Institute. Among patients with symptomatic MM, 74% presented with CRAB symptoms, 20% presented with non-CRAB manifestations, and 6% had both clinical features. Ten categories of non-CRAB manifestations were found, in order of decreasing frequency: neuropathy (because of spinal cord compression, nerve root compression, or peripheral neuropathy), extramedullary involvement, hyperviscosity syndrome, concomitant amyloidosis (eg, nephrotic syndrome or cardiopathy), hemorrhage/coagulopathy, systemic symptoms (eg, fever or weight loss), primary plasma cell leukemia, infections, cryoglobulinemia, and secondary gout. Kaplan-Meier estimates of survival in patients with non-CRAB manifestations did not show a significant difference from the survival of patients presenting with CRAB symptoms. Presenting symptoms of MM may be grouped in a total of 14 categories, 4 for the CRAB and 10 for the less common non-CRAB features. Grouped together, non-CRAB manifestations do not appear to confer a negative effect on the prognosis of patients with MM.

50 CFR 648.263 - Red crab possession and landing restrictions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE FISHERIES OF THE NORTHEASTERN UNITED STATES Management Measures for the Atlantic Deep-Sea Red Crab Fishery § 648.263 Red crab possession and landing...

Nearshore distribution and abundance of Dungeness crabs in Glacier Bay National Park, Alaska

USGS Publications Warehouse

O'Clair, Charles E.; Freese, J. Lincoln; Stone, Robert P.; Shirley, Thomas C.; Leder, Erica H.; Taggart, S. James; Kruse, Gordon H.; Engstrom, Daniel R.

1995-01-01

As part of an ongoing, multi-agency study to determine the effects of closure of the commercial fishery for Dungeness crabs, Cancer magister, on crab population structure we examined patterns of distribution and abundance of crabs in nearshore habitats at five locations in and near Glacier Bay National Park. Sampling was conducted in April and September 1992 and April 1993 prior to the anticipated closure of the fishery in the park. Divers censused crabs by sex and reproductive state (ovigerous/nonovigerous females) along belt transects (2m x 100m) laid perpendicular to shore in the depth range 0 m (mean lower low water) to 18 m.Preliminary results from the first three sampling periods revealed that the average densities of Dungeness crabs at the five locations ranged from 78 to 2012 crabs/ha. Crab densities differed between populations depending on sex, reproductive state of females and sampling period. Male crabs showed reduced densities at Gustavus Flats in April 1992 (P<0.01) and 1993 (P<0.001). Ovigerous females had greater density at Bartlett Cove in April 1993 (P<0.001). Sex ratios were frequently skewed toward females. At Bartlett Cove and Gustavus Flats females outnumbered males in April 1992 and 1993 (P<0.001). Most of the females at Bartlett Cove and Gustavus Flats in April 1992 and 1993 were ovigerous (P-0.001). Males tended to occupy greater depths than females in April 1992 (P<0.05) but not April 1993 (P-005). The mean depth of males shifted from deeper to shallower water between April and September 1992 (P<0.001). The depth distribution of ovigerous crabs did not differ from that of nonovigerous female crabs. Future research prior to the anticipated closure of the commercial Dungeness crab fishery in Glacier Bay will include a tagging study to determine the extent of crab movement and further study of the temporal as well as the spatial variability observed in the structure of these populations.

Impacts to Dungeness Crab from the Southwest Washington Littoral Drift Restoration Project

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

Williams, Greg D.; Kohn, Nancy P.; Pearson, Walter H.

2005-11-09

The Benson Beach littoral drift restoration project is a demonstration project that will replenish sand on Benson Beach, the public beach north of the North Jetty at the mouth of the Columbia River (MCR), using material dredged from the river during normal maintenance dredging of the navigational channel. A U.S. Army Corps of Engineers (Corps) proposal involves pumping the material from a sump area on the south side of the jetty to Benson Beach using a cutter suction dredge, also known as a pipeline dredge. If this one-time demonstration project proves feasible and successful, up to a million cubic yardsmore » of sediment could be used to replenish the outer coast littoral drift system in successive years by the same process. The primary goal of this study was to assess the potential risk of impacts to Dungeness crab from the proposed Benson Beach littoral drift restoration process of using the cutter suction dredge to move sediment from the proposed sump area on one side of the North Jetty to the beach on the other side of the jetty. Because there are no direct measurements of crab entrainment by pipeline dredge operating outside of the lower Columbia River navigation channel, dredge impacts for the proposed demonstration project were estimated using a modification of the dredge impact model (DIM) of Armstrong et al. (1987). The model estimates adult equivalent loss (AEL) of crabs using crab population density from trawl surveys, dredge project information (gear type, season, location, volume), and an entrainment function relating crab population density to entrainment by the dredge. The input used in applying the DIM to the Benson Beach littoral drift restoration included the specific dredging scenario provided by the Corps, existing data on crab density in previously proposed sump areas, and a series of entrainment functions. A total of fourteen scenarios were modeled and the outcomes compared with six reference scenarios intended to represent realistic to

Proximate and mineral composition of crab meat consumed in Bahrain.

PubMed

Musaiger, Abdulrahman O; Al-Rumaidh, Mohammed J

2005-06-01

The proximate, mineral and heavy metals of raw and cooked crab meat, Portunus pelagicus, consumed in Bahrain were studied. The crab meat contains a good level of protein (17.5-18.8%), with very low proportion of fat (0.6-1.4%). The levels of sodium, potassium, calcium and phosphorus were found to be higher than other minerals. Traces of heavy metals (lead, mercury, cadmium) were also reported. Traditional cooking had a considerable effect on proximate and mineral contents of crab meat.

Invasive ants compete with and modify the trophic ecology of hermit crabs on tropical islands.

PubMed

McNatty, Alice; Abbott, Kirsti L; Lester, Philip J

2009-05-01

Invasive species can dramatically alter trophic interactions. Predation is the predominant trophic interaction generally considered to be responsible for ecological change after invasion. In contrast, how frequently competition from invasive species contributes to the decline of native species remains controversial. Here, we demonstrate how the trophic ecology of the remote atoll nation of Tokelau is changing due to competition between invasive ants (Anoplolepis gracilipes) and native terrestrial hermit crabs (Coenobita spp.) for carrion. A significant negative correlation was observed between A. gracilipes and hermit crab abundance. On islands with A. gracilipes, crabs were generally restricted to the periphery of invaded islands. Very few hermit crabs were found in central areas of these islands where A. gracilipes abundances were highest. Ant exclusion experiments demonstrated that changes in the abundance and distribution of hermit crabs on Tokelau are a result of competition. The ants did not kill the hermit crabs. Rather, when highly abundant, A. gracilipes attacked crabs by spraying acid and drove crabs away from carrion resources. Analysis of naturally occurring N and C isotopes suggests that the ants are effectively lowering the trophic level of crabs. According to delta(15) N values, hermit crabs have a relatively high trophic level on islands where A. gracilipes have not invaded. In contrast, where these ants have invaded we observed a significant decrease in delta(15) N for all crab species. This result concurs with our experiment in suggesting long-term exclusion from carrion resources, driving co-occurring crabs towards a more herbivorous diet. Changes in hermit crab abundance or distribution may have major ramifications for the stability of plant communities. Because A. gracilipes have invaded many tropical islands where the predominant scavengers are hermit crabs, we consider that their competitive effects are likely to be more prominent in

Conservation status of the American horseshoe crab, (Limulus polyphemus): A regional assessment

USGS Publications Warehouse

Smith, David R.; Brockmann, H. Jane; Beekey, Mark A.; King, Timothy L.; Millard, Michael J.; Zaldívar-Rae, Jaime

2017-01-01

Horseshoe crabs have persisted for more than 200 million years, and fossil forms date to 450 million years ago. The American horseshoe crab (Limulus polyphemus), one of four extant horseshoe crab species, is found along the Atlantic coastline of North America ranging from Alabama to Maine, USA with another distinct population on the coasts of Campeche, Yucatán and Quintana Roo in the Yucatán Peninsula, México. Although the American horseshoe crab tolerates broad environmental conditions, exploitation and habitat loss threaten the species. We assessed the conservation status of the American horseshoe crab by comprehensively reviewing available scientific information on its range, life history, genetic structure, population trends and analyses, major threats, and conservation. We structured the status assessment by six genetically-informed regions and accounted for sub-regional differences in environmental conditions, threats, and management. The transnational regions are Gulf of Maine (USA), Mid-Atlantic (USA), Southeast (USA), Florida Atlantic (USA), Northeast Gulf of México (USA), and Yucatán Peninsula (México). Our conclusion is that the American horseshoe crab species is vulnerable to local extirpation and that the degree and extent of risk vary among and within the regions. The risk is elevated in the Gulf of Maine region due to limited and fragmented habitat. The populations of horseshoe crabs in the Mid-Atlantic region are stable in the Delaware Bay area, and regulatory controls are in place, but the risk is elevated in the New England area as evidenced by continuing declines understood to be caused by over-harvest. The populations of horseshoe crabs in the Southeast region are stable or increasing. The populations of horseshoe crabs in the Florida Atlantic region show mixed trends among areas, and continuing population reductions at the embayment level have poorly understood causes. Within the Northeast Gulf of Mexico, causes of population trends are

Assessing potential impacts of energized submarine power cables on crab harvests

NASA Astrophysics Data System (ADS)

Love, Milton S.; Nishimoto, Mary M.; Clark, Scott; McCrea, Merit; Bull, Ann Scarborough

2017-12-01

Offshore renewable energy facilities transmit electricity to shore through submarine power cables. Electromagnetic field emissions (EMFs) are generated from the transmission of electricity through these cables, such as the AC inter-array (between unit) and AC export (to shore) cables often used in offshore energy production. The EMF has both an electric component and a magnetic component. While sheathing can block the direct electric field, the magnetic field is not blocked. A concern raised by fishermen on the Pacific Coast of North America is that commercially important Dungeness crab (Metacarcinus magister Dana, 1852)) might not cross over an energized submarine power cable to enter a baited crab trap, thus potentially reducing their catch. The presence of operating energized cables off southern California and in Puget Sound (cables that are comparable to those within the arrays of existing offshore wind energy devices) allowed us to conduct experiments on how energized power cables might affect the harvesting of both M. magister and another commercially important crab species, Cancer productus Randall, 1839. In this study we tested the questions: 1) Is the catchability of crabs reduced if these animals must traverse an energized power cable to enter a trap and 2) if crabs preferentially do not cross an energized cable, is it the cable structure or the EMF emitted from that cable that deters crabs from crossing? In field experiments off southern California and in Puget Sound, crabs were given a choice of walking over an energized power cable to a baited trap or walking directly away from that cable to a second baited trap. Based on our research we found no evidence that the EMF emitted by energized submarine power cables influenced the catchability of these two species of commercially important crabs. In addition, there was no difference in the crabs' responses to lightly buried versus unburied cables. We did observe that, regardless of the position of the cable

50 CFR 648.262 - Accountability measures for red crab limited access vessels.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 10 2011-10-01 2011-10-01 false Accountability measures for red crab... UNITED STATES Management Measures for the Atlantic Deep-Sea Red Crab Fishery § 648.262 Accountability measures for red crab limited access vessels. (a) Closure authority. NMFS shall close the EEZ to fishing...

Crabs Mediate Interactions between Native and Invasive Salt Marsh Plants: A Mesocosm Study

PubMed Central

Zhang, Xiao-dong; Jia, Xin; Chen, Yang-yun; Shao, Jun-jiong; Wu, Xin-ru; Shang, Lei; Li, Bo

2013-01-01

Soil disturbance has been widely recognized as an important factor influencing the structure and dynamics of plant communities. Although soil reworkers were shown to increase habitat complexity and raise the risk of plant invasion, their role in regulating the interactions between native and invasive species remains unclear. We proposed that crab activities, via improving soil nitrogen availability, may indirectly affect the interactions between invasive Spartina alterniflora and native Phragmites australis and Scirpus mariqueter in salt marsh ecosystems. We conducted a two-year mesocosm experiment consisting of five species combinations, i.e., monocultures of three species and pair-wise mixtures of invasive and native species, with crabs being either present or absent for each combination. We found that crabs could mitigate soil nitrogen depletion in the mesocosm over the two years. Plant performance of all species, at both the ramet-level (height and biomass per ramet) and plot-level (density, total above- and belowground biomass), were promoted by crab activities. These plants responded to crab disturbance primarily by clonal propagation, as plot-level performance was more sensitive to crabs than ramet-level. Moreover, crab activities altered the competition between Spartina and native plants in favor of the former, since Spartina was more promoted than native plants by crab activities. Our results suggested that crab activities may increase the competition ability of Spartina over native Phragmites and Scirpus through alleviating soil nitrogen limitation. PMID:24023926

Resistance of nerves from certain toxic crabs to paralytic shellfish poison and tetrodotoxin.

PubMed

Daigo, K; Noguchi, T; Miwa, A; Kawai, N; Hashimoto, K

1988-01-01

The inhibitory effect of paralytic shellfish poison and tetrodotoxin on nerves from toxic and nontoxic crabs was examined. The toxins at concentrations of 10(-3) - 10(-4) M partially or completely inhibited the action potential of nerves isolated from the legs of toxic crab species (Zosimus aeneus, Atergatis floridus and Platypodia granulosa), but had no effect at 10(-6) M, the concentration at which the action potential of nerves from a nontoxic crab (Plagusia dentipes) was inhibited completely. A xanthid crab Daira perlata was intermediate in respect to the resistance to toxins. These results agree with the previous results obtained by i.p. administration of both toxins into those crabs.

Hard X-ray Variations in the Crab Nebula

NASA Technical Reports Server (NTRS)

Wilson-Hodge, Colleen A.; Cherry, M. L.; Case, G. L.; Baumgartner, W. H.; Beklen, E.; Bhat, P. N.; Briggs, M. S.; Camero-Arranz, A.; Chaplin, V.; Connaughton, V.;

Hard X-ray Variations in the Crab Nebula

NASA Technical Reports Server (NTRS)

Wilson-Hodge, Colleen A.; Cherry, M. L.; Case, G. L.; Baumgarter, W. H.; Beklen, E.; Bhat, P. N.; Briggs, M. S.; Camero-Arranz, A.; Chaplin, V.; Connaughton, V.;

Hard X-ray Variations in the Crab Nebula

NASA Technical Reports Server (NTRS)

Wilson-Hodge, Colleen A.; Cherry, M. L.; Case, G. L.; Baumgartner, W. H.; Beklen, E.; Bhat, P. N.; Briggs, M. S.; Camero-Arranz, A.; Connaughton, V.; Finger, M. H.;

NASA KingAir #801 during takeoff

NASA Technical Reports Server (NTRS)

1999-01-01

NASA KingAir N801NA during takeoff. The Beechcraft Beech 200 Super KingAir aircraft N7NA, known as NASA 7, has been a support aircraft for many years, flying 'shuttle' missions to Ames Research Center. It once flew from the Jet Propulsion Laboratory and back each day but now (2001) flies between the Dryden Flight Research Center and Ames. Dryden assumed the mission and aircraft in September 1996. A second Beechcraft Beech 200 Super King Air, N701NA, redesignated N801NA, transferred to Dryden on 3 Oct. 1997 and is used for research missions but substitutes for NASA 7 on shuttle missions when NASA 7 is not available.

Goldie Brangman Remembers the Operation to Save Dr King.

PubMed

Koch, Evan; Brangman, Goldie

2015-12-01

In September 1958 the Rev Dr Martin Luther King Jr was stabbed and nearly assassinated. Surgeons at Harlem Hospital in New York City removed a 17.8-cm (7-in)-long letter opener from Dr King's chest. Certified Registered Nurse Anesthetist Goldie Brangman remembers this event because she participated in Dr King's anesthetic. This article correlates Brangman's memories with published accounts of the event. It also places the event within the context of the modern civil rights movement that Dr King led.

A Hyperspectral View of the Crab Nebula

NASA Astrophysics Data System (ADS)

Charlebois, M.; Drissen, L.; Bernier, A.-P.; Grandmont, F.; Binette, L.

2010-05-01

We have obtained spatially resolved spectra of the Crab nebula in the spectral ranges 450-520 nm and 650-680 nm, encompassing the Hβ, [O III] λ4959, λ5007, Hα, [N II] λ6548, λ6584, and [S II] λ6717, λ6731 emission lines, with the imaging Fourier transform spectrometer SpIOMM at the Observatoire du Mont-Mégantic's 1.6 m telescope. We first compare our data with published observations obtained either from a Fabry-Perot interferometer or from a long-slit spectrograph. Using a spectral deconvolution technique similar to the one developed by Čadež et al., we identify and resolve multiple emission lines separated by large Doppler shifts and contained within the rapidly expanding filamentary structure of the Crab. This allows us to measure important line ratios, such as [N II]/Hα, [S II]/Hα, and [S II] λ6717 /[S II] λ6731 of individual filaments, providing a new insight on the SE-NW asymmetry in the Crab. From our analysis of the spatial distribution of the electronic density and of the respective shocked versus photoionized gas components, we deduce that the skin-less NW region must have evolved faster than the rest of the nebula. Assuming a very simple expansion model for the ejecta material, our data provide us with a complete tridimensional view of the Crab.

Loss of eelgrass in Casco Bay, Maine, linked to Green Crab disturbance

USGS Publications Warehouse

Neckles, Hilary A.

2015-01-01

Over half of the Zostera marina (Eelgrass) cover disappeared from Casco Bay, ME, largely between 2012 and 2013. Eelgrass decline coincided with a population explosion of the invasive crab Carcinus maenas (European Green Crab). Green Crabs have been found to damage Eelgrass in Atlantic Canada through foraging activity, but destruction of established beds had not been documented in Maine. My objective was to determine whether loss of Eelgrass from Casco Bay was related to Green Crab disturbance. In September 2013, I transplanted Eelgrass shoots inside and outside of replicate Green Crab exclosures in a formerly vegetated area of upper Casco Bay. Following 26 d, mean survival of Eelgrass inside the exclosures was 82% and outside the exclosures was 24%. The mean plastochrone interval (time between formation of 2 successive leaves) of undamaged shoots was the same inside and outside the exclosures, and was comparable to published values from healthy Eelgrass beds in New England. Results implicate Green Crab bioturbation as a leading cause of Eelgrass loss from this system.

78 FR 4391 - North Pacific Fishery Management Council; Public Meetings

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-22

...); Initial review of AFA Vessel Replacement GOA Sideboards. 4. GOA Trawl Issues: Discussion paper on Central Gulf of Alaska (CGOA) Trawl Economic Data Collection; Discussion paper on CGOA Trawl Catch Shares... paper on Bristol Bay red king crab. 3. Groundfish Issues: Discussion paper on crab bycatch limits in...

50 CFR 680.6 - Crab economic data report (EDR).

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 13 2013-10-01 2013-10-01 false Crab economic data report (EDR). 680.6... ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) SHELLFISH FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA General § 680.6 Crab economic data report (EDR). (a) Requirements. (1) Any owner or leaseholder of a...

50 CFR 680.6 - Crab economic data report (EDR).

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false Crab economic data report (EDR). 680.6... ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) SHELLFISH FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA General § 680.6 Crab economic data report (EDR). (a) Requirements. (1) Any owner or leaseholder of a...

40 CFR 408.20 - Applicability; description of the conventional blue crab processing subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... conventional blue crab processing subcategory. 408.20 Section 408.20 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Conventional Blue Crab Processing Subcategory § 408.20 Applicability; description of the conventional blue crab processing subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 408.20 - Applicability; description of the conventional blue crab processing subcategory.

Code of Federal Regulations, 2012 CFR

2012-07-01

... conventional blue crab processing subcategory. 408.20 Section 408.20 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Conventional Blue Crab Processing Subcategory § 408.20 Applicability; description of the conventional blue crab processing subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 408.30 - Applicability; description of the mechanized blue crab processing subcategory.

Code of Federal Regulations, 2012 CFR

2012-07-01

... mechanized blue crab processing subcategory. 408.30 Section 408.30 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Mechanized Blue Crab Processing Subcategory § 408.30 Applicability; description of the mechanized blue crab processing subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 408.30 - Applicability; description of the mechanized blue crab processing subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... mechanized blue crab processing subcategory. 408.30 Section 408.30 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Mechanized Blue Crab Processing Subcategory § 408.30 Applicability; description of the mechanized blue crab processing subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 408.30 - Applicability; description of the mechanized blue crab processing subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... mechanized blue crab processing subcategory. 408.30 Section 408.30 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Mechanized Blue Crab Processing Subcategory § 408.30 Applicability; description of the mechanized blue crab processing subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 408.30 - Applicability; description of the mechanized blue crab processing subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... mechanized blue crab processing subcategory. 408.30 Section 408.30 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Mechanized Blue Crab Processing Subcategory § 408.30 Applicability; description of the mechanized blue crab processing subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 408.20 - Applicability; description of the conventional blue crab processing subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... conventional blue crab processing subcategory. 408.20 Section 408.20 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Conventional Blue Crab Processing Subcategory § 408.20 Applicability; description of the conventional blue crab processing subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 408.20 - Applicability; description of the conventional blue crab processing subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... conventional blue crab processing subcategory. 408.20 Section 408.20 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Conventional Blue Crab Processing Subcategory § 408.20 Applicability; description of the conventional blue crab processing subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 408.20 - Applicability; description of the conventional blue crab processing subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... conventional blue crab processing subcategory. 408.20 Section 408.20 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Conventional Blue Crab Processing Subcategory § 408.20 Applicability; description of the conventional blue crab processing subcategory. The provisions of this subpart are applicable to discharges...

40 CFR 408.30 - Applicability; description of the mechanized blue crab processing subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... mechanized blue crab processing subcategory. 408.30 Section 408.30 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Mechanized Blue Crab Processing Subcategory § 408.30 Applicability; description of the mechanized blue crab processing subcategory. The provisions of this subpart are applicable to discharges...

Habits and customs of crab catchers in southern Bahia, Brazil.

PubMed

Firmo, Angélica M S; Tognella, Mônica M P; Tenório, Gabrielle D; Barboza, Raynner R D; Alves, Rômulo R N

2017-08-23

Brazilian mangrove forests are widely distributed along the coast and exploited by groups of people with customs and habits as diverse as the biology of the mangrove ecosystems. This study identifies different methods of extracting crabs that inhabit the mangrove belts; some of these activities, such as catching individual crabs by hand, are aimed at maintaining natural stocks of this species in Mucuri (south Bahia), Brazil. In the studied community, illegal hunting activities that violate Brazilian legislation limiting the use of tangle-netting in mangrove ecosystem were observed. According to our observations, fishermen, to catch individual crabs, use the tangle-netting technique seeking to increase income and are from families that have no tradition of extraction. This analysis leads us to conclude that catchers from economically marginalised social groups enter mangroves for purposes of survival rather than for purposes of subsistence, because the catching by tangle-netting is a predatory technique. Tangle-netting  technique increase caught but also increases their mortality rate. We emphasise that traditional catching methods are unique to Brazil and that manual capturing of crab should be preserved through public policies aimed at maintaining the crab population.

Domoic acid excretion in dungeness crabs, razor clams and mussels.

PubMed

Schultz, Irvin R; Skillman, Ann; Woodruff, Dana

2008-07-01

Domoic acid (DA) is a neurotoxic amino acid produced by several marine algal species of the Pseudo-nitzschia (PN) genus. We studied the elimination of DA from hemolymph after intravascular (IV) injection in razor clams (Siliqua patula), mussels (Mytilus edulis) and Dungeness crabs (Cancer magister). Crabs were also injected with two other organic acids, dichloroacetic acid (DCAA) and kainic acid (KA). For IV dosing, hemolymph was repetitively sampled and DA concentrations measured by HPLC-UV. Toxicokinetic analysis of DA in crabs suggested most of the injected dose remained within hemolymph compartment with little extravascular distribution. This observation is in sharp contrast to results obtained from clams and mussels which exhibited similarly large apparent volumes of distribution despite large differences in overall clearance. These findings suggest fundamentally different storage and elimination processes are occurring for DA between bivalves and crabs.

TeV radiation from the Crab nebula and other matters

NASA Technical Reports Server (NTRS)

Lamb, R. C.

1990-01-01

The detection of the Crab Nebula via the Cherenkov imaging technique places TeV astronomy on a secure observational footing. The motivation for TeV observations, a discussion of the atmospheric Cherenkov technique, the experimental details of the Crab Nebula detection, and its scientific implications are presented. The present dilemma of VHE/UHE astronomy is that the Crab appears to be the only source whose showers match theoretical expectations. The situation will be clarified as improved ground-based detectors come on-line with sensitivities matching those of the GRO (Gamma Ray Observatory) instruments.

Boxer crabs induce asexual reproduction of their associated sea anemones by splitting and intraspecific theft.

PubMed

Schnytzer, Yisrael; Giman, Yaniv; Karplus, Ilan; Achituv, Yair

2017-01-01

Crabs of the genus Lybia have the remarkable habit of holding a sea anemone in each of their claws. This partnership appears to be obligate, at least on the part of the crab. The present study focuses on Lybia leptochelis from the Red Sea holding anemones of the genus Alicia (family Aliciidae). These anemones have not been found free living, only in association with L. leptochelis . In an attempt to understand how the crabs acquire them, we conducted a series of behavioral experiments and molecular analyses. Laboratory observations showed that the removal of one anemone from a crab induces a "splitting" behavior, whereby the crab tears the remaining anemone into two similar parts, resulting in a complete anemone in each claw after regeneration. Furthermore, when two crabs, one holding anemones and one lacking them, are confronted, the crabs fight, almost always leading to the "theft" of a complete anemone or anemone fragment by the crab without them. Following this, crabs "split" their lone anemone into two. Individuals of Alicia sp. removed from freshly collected L. leptochelis were used for DNA analysis. By employing AFLP (Fluorescence Amplified Fragments Length Polymorphism) it was shown that each pair of anemones from a given crab is genetically identical. Furthermore, there is genetic identity between most pairs of anemone held by different crabs, with the others showing slight genetic differences. This is a unique case in which one animal induces asexual reproduction of another, consequently also affecting its genetic diversity.

Chandra Observations of the Crab: A Progress Report

NASA Technical Reports Server (NTRS)

Weisskopf, Martin C.

2012-01-01

Recently there have been two important findings concerning the Crab both of which are highlighted in this workshop. One finding was the discovery, using the AGILE and Fermi satellites, of gamma-ray flares from the direction of the Crab Nebula. The other finding was the variability, up to 7%, with time scales of the order of a year of the integrated hard X-ray emission. We have been using the Chandra X-Ray observatory to monitor the Crab on a monthly cadence since just after the 2010 September gamma-ray flare. We were also fortunate to trigger series of preplanned target of opportunity observations during the 2011 April flare. Our monitoring observations are on-going and will extend, at a minimum until the fall of 2012. We present an update and overview of these observations.

A glitch in the Crab pulsar (PSR B0531+21)

NASA Astrophysics Data System (ADS)

Shaw, Benjamin; Lyne, Andrew; Bassa, Cees; Breton, Rene; Jordan, Christine; Keith, Michael; Mickaliger, Mitchell B.; Stappers, Benjamin; Weltevrede, Patrick

2018-05-01

We have detected a glitch in the Crab pulsar, B0531+21, on 2018-04-29. The Crab pulsar is regularly monitored with the 42-ft and Lovell telescopes at the Jodrell Bank Observatory as part of the pulsar timing programme.

Acanthocephala Parasite (Profilicollis spp.) Loads in Correlation to Pacific Mole Crab (Emerita analoga) Size

NASA Astrophysics Data System (ADS)

Cheng, T.; Huang, S.; Galathe, M.; Jenkins, M.; Ramirez, A.; Crosby, L.; Barrera, J.; FitzHoward, S.

2013-12-01

Since 2002, San Francisco Bay students have been conducting marine ecosystem monitoring through a joint project with the Long-term Monitoring Program and Experiential Training for Students (LiMPETS), in conjunction with the Gulf of Farallones National Marine Sanctuary. Each year students collect population and demographic data on Pacific mole crabs (Emerita analoga), an indicator species that lives in the sandy beach habitat in temperate regions along the Pacific Ocean. Pacific mole crabs are filter feeding crustaceans that inhabit the intertidal swash zone and are known to be an intermediate host for parasitic ';spiny-headed' worms in the phylum Acanthocephala (Profilicollis spp.). Sampling takes place during their reproductive period, which occurs from spring to fall, and includes measuring total body length of the Pacific mole crabs and dissecting them to determine presence of Acanthocephalan parasites. We hypothesize that due to larger body mass, larger Pacific mole crabs will have a greater number of Acanthocephala parasites.We conducted several analyses using the LiMPETS long-term data. Specifically, we compared body length, crab gender, and parasite abundance from Pacific mole crabs sampled from four beaches located in the county and city of San Francisco. Our results indicated that larger Pacific mole crabs do not necessarily have more parasites, but are more likely to have at least one parasite, while female Pacific mole crabs carrying eggs, have more parasites than males or females without eggs. We also found that parasite loads per mole crab was highest in the spring. Further analysis will be conducted to determine factors affecting Pacific mole crab parasite loads. Studying Pacific mole crabs help evaluate the health of California's intertidal systems and how human activities, geologic changes, and climate changes all make huge impacts to the intertidal ecosystems.

Reproductive biology of the female Jonah crab from the Maryland-Virginia Coastal Zone

NASA Astrophysics Data System (ADS)

Dunn, H.; Stevens, B. G.

2016-02-01

Jonah crabs, Cancer borealis, have long been considered a bycatch of the lobster industry. Jonah crab harvest is not regulated, there are no fishing size limits, nor restrictions to protect females. The study sampled Jonah crabs from one area in the Maryland-Virginia coastal zone from a local fishing vessel in June and July of 2015. This study is based on examination of the gross anatomy of 49 crabs and on histological preparations from 29 crabs. Ovary development stages were created and ordered based on area of oocytes, color and size of ovary, and the presence of sperm plugs. Four stages were observed but five are identifiable. Size at 50% sexual maturity (SM50), for females, as indicated by vulvar condition and oocyte area, was estimated to be 49.46 mm carapace length (CL). No prior information or study has been published concerning female Jonah crabs. This fishery-independent data is vital to ensure long-term sustainability, and develop appropriate management for this species.

Comparative biology of the crab Goniopsis cruentata: geographic variation of body size, sexual maturity, and allometric growth

NASA Astrophysics Data System (ADS)

de Lira, José Jonathas Pereira Rodrigues; Calado, Tereza Cristina dos Santos; Rezende, Carla Ferreira; Silva, José Roberto Feitosa

2015-12-01

Geographic variation of phenotypic traits is common across species and is often associated with variation in environmental conditions. Here, we found larger bodies and larger size at maturity in a northward, lower latitude population of the crab Goniopsis cruentata, which inhabits a hotter, drier environment in comparison with a southward, higher latitude population. Furthermore, the juvenile male gonopods grow more relative to body size in the population characterized by maturation at a smaller size. In contrast, the female abdomen widens at a higher rate among the late maturing population. These results provide further evidence that local environmental conditions play a role in phenotypic variation between populations inhabiting different latitudes. Moreover, they also show that variation in size at maturity and body size can lead to divergent allometric patterns of sexual characteristics that can have a sex-specific response.

50 CFR 680.3 - Relation to other laws.

Code of Federal Regulations, 2013 CFR

2013-10-01

....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... governing the conservation and management of king crab and Tanner crab in the BSAI area are contained in 50... requirements using the ADF&G “Intent to Operate” registration form and “Fish Tickets.” (b) Sport, personal use...

50 CFR 680.3 - Relation to other laws.

Code of Federal Regulations, 2011 CFR

2011-10-01

....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... governing the conservation and management of king crab and Tanner crab in the BSAI area are contained in 50... requirements using the ADF&G “Intent to Operate” registration form and “Fish Tickets.” (b) Sport, personal use...

50 CFR 680.3 - Relation to other laws.

Code of Federal Regulations, 2014 CFR

2014-10-01

....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... governing the conservation and management of king crab and Tanner crab in the BSAI area are contained in 50... requirements using the ADF&G “Intent to Operate” registration form and “Fish Tickets.” (b) Sport, personal use...

50 CFR 680.3 - Relation to other laws.

Code of Federal Regulations, 2010 CFR

2010-10-01

....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... governing the conservation and management of king crab and Tanner crab in the BSAI area are contained in 50... requirements using the ADF&G “Intent to Operate” registration form and “Fish Tickets.” (b) Sport, personal use...

50 CFR 680.3 - Relation to other laws.

Code of Federal Regulations, 2012 CFR

2012-10-01

....3 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... governing the conservation and management of king crab and Tanner crab in the BSAI area are contained in 50... requirements using the ADF&G “Intent to Operate” registration form and “Fish Tickets.” (b) Sport, personal use...

Crab cavities: Past, present, and future of a challenging device

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

Wu, Q.

2015-05-03

In two-ring facilities operating with a crossing-angle collision scheme, luminosity can be limited due to an incomplete overlapping of the colliding bunches. Crab cavities then are introduced to restore head-on collisions by providing the destined opposite deflection to the head and tail of the bunch. An increase in luminosity was demonstrated at KEKB with global crab-crossing, while the Large Hardron Collider (LHC) at CERN currently is designing local crab crossing for the Hi-Lumi upgrade. Future colliders may investigate both approaches. In this paper, we review the challenges in the technology, and the implementation of crab cavities, while discussing experience inmore » earlier colliders, ongoing R&D, and proposed implementations for future facilities, such as HiLumi-LHC, CERN’s compact linear collider (CLIC), the international linear collider (ILC), and the electron-ion collider under design at BNL (eRHIC).« less

Boxer crabs induce asexual reproduction of their associated sea anemones by splitting and intraspecific theft

PubMed Central

Karplus, Ilan; Achituv, Yair

2017-01-01

Crabs of the genus Lybia have the remarkable habit of holding a sea anemone in each of their claws. This partnership appears to be obligate, at least on the part of the crab. The present study focuses on Lybia leptochelis from the Red Sea holding anemones of the genus Alicia (family Aliciidae). These anemones have not been found free living, only in association with L. leptochelis. In an attempt to understand how the crabs acquire them, we conducted a series of behavioral experiments and molecular analyses. Laboratory observations showed that the removal of one anemone from a crab induces a “splitting” behavior, whereby the crab tears the remaining anemone into two similar parts, resulting in a complete anemone in each claw after regeneration. Furthermore, when two crabs, one holding anemones and one lacking them, are confronted, the crabs fight, almost always leading to the “theft” of a complete anemone or anemone fragment by the crab without them. Following this, crabs “split” their lone anemone into two. Individuals of Alicia sp. removed from freshly collected L. leptochelis were used for DNA analysis. By employing AFLP (Fluorescence Amplified Fragments Length Polymorphism) it was shown that each pair of anemones from a given crab is genetically identical. Furthermore, there is genetic identity between most pairs of anemone held by different crabs, with the others showing slight genetic differences. This is a unique case in which one animal induces asexual reproduction of another, consequently also affecting its genetic diversity. PMID:28168117

Trophic behaviour of juvenile reef fishes inhabiting interlinked mangrove-seagrass habitats in offshore mangrove islets.

PubMed

Vaslet, A; Phillips, D L; France, C A M; Feller, I C; Baldwin, C C

2015-08-01

Stable isotope (δ(13)C and δ(15)N) and gut content analyses were used to investigate size-related feeding habits of four reef fishes (the beaugregory Stegastes leucostictus, the french grunt Haemulon flavolineatum, the schoolmaster snapper Lutjanus apodus and the yellowtail snapper Ocyurus chrysurus) inhabiting an offshore (non-estuarine) mangrove islet off Belize, Central America. Comparisons of isotopic niche space and Schoener diet similarity index suggested a low to moderate degree of niche overlap between fish size groups. The δ(13)C gradient between mangrove and seagrass prey as well as results of Bayesian mixing models revealed that sampled fishes relied mostly on seagrass prey items. Only small and large juveniles of the carnivorous species L. apodus derived a part of their diet from mangroves by targeting mangrove-associated Grapsidae crabs and fish prey, respectively. Isotopic niche shifts were particularly obvious for carnivorous fishes that ingested larger prey items (Xanthidae crabs and fishes) during their ontogeny. The utilization of mangrove food resources is less than expected and depends on the ecology and life history of the fish species considered. This research highlights that mangrove-derived carbon contributed relatively little to the diets of four fish taxa from an offshore mangrove islet. © 2015 The Fisheries Society of the British Isles.

The largest glitch observed in the Crab pulsar

NASA Astrophysics Data System (ADS)

Shaw, B.; Lyne, A. G.; Stappers, B. W.; Weltevrede, P.; Bassa, C. G.; Lien, A. Y.; Mickaliger, M. B.; Breton, R. P.; Jordan, C. A.; Keith, M. J.; Krimm, H. A.

2018-05-01

We have observed a large glitch in the Crab pulsar (PSR B0531+21). The glitch occurred around MJD 58064 (2017 November 8) when the pulsar underwent an increase in the rotation rate of Δν = 1.530 × 10-5 Hz, corresponding to a fractional increase of Δν/ν = 0.516 × 10-6 making this event the largest glitch ever observed in this source. Due to our high-cadence and long-dwell time observations of the Crab pulsar we are able to partially resolve a fraction of the total spin-up of the star. This delayed spin-up occurred over a timescale of ˜1.7 days and is similar to the behaviour seen in the 1989 and 1996 large Crab pulsar glitches. The spin-down rate also increased at the glitch epoch by Δ \\dot{ν } / \\dot{ν } = 7 × 10^{-3}. In addition to being the largest such event observed in the Crab, the glitch occurred after the longest period of glitch inactivity since at least 1984 and we discuss a possible relationship between glitch size and waiting time. No changes to the shape of the pulse profile were observed near the glitch epoch at 610 MHz or 1520 MHz, nor did we identify any changes in the X-ray flux from the pulsar. The long-term recovery from the glitch continues to progress as \\dot{ν } slowly rises towards pre-glitch values. In line with other large Crab glitches, we expect there to be a persistent change to \\dot{ν }. We continue to monitor the long-term recovery with frequent, high quality observations.

50 CFR 654.24 - Shrimp/stone crab separation zones.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Shrimp/stone crab separation zones. 654.24... Measures § 654.24 Shrimp/stone crab separation zones. Five zones are established in the management area and... trapping. The zones are as shown in Appendix A, Figure 3, of this part. Although Zone II is entirely within...

50 CFR 654.24 - Shrimp/stone crab separation zones.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 10 2011-10-01 2011-10-01 false Shrimp/stone crab separation zones. 654... Measures § 654.24 Shrimp/stone crab separation zones. Five zones are established in the management area and... trapping. The zones are as shown in Appendix A, Figure 3, of this part. Although Zone II is entirely within...

Hermit crabs in the diet of Pigeon Guillemots at Kachemak Bay, Alaska

USGS Publications Warehouse

Litzow, Michael A.; Piatt, John F.; Figurski, Jared D.

1998-01-01

Guillemots (Cepphus spp.) feed their chicks a diet that is almost exclusively fish. We observed Pigeon Guillemots (C. columba) at two colonies in Alaska where hermit crabs (Crustacea: Anomura) were a major part of the diet for some nestlings. Hermit crabs were delivered to three of five observed nests at one colony, comprised between 2% and 22% of the items delivered at those nests, and were the second most common food type at one nest. Hermit crabs may be an attractive prey item when lipid-rich forage fish are scarce, and crabs living in gastropod shells that have been softened by encrustations of Suberites sponges may be vulnerable to guillemot predation.

Associations between dioxins/furans and dioxin-like PCBs in estuarine sediment and blue crab

USGS Publications Warehouse

Liebens, J.; Mohrherr, C.J.; Karouna-Renier, N. K.; Snyder, R.A.; Rao, K.R.

2011-01-01

The objective of the present study was to evaluate the relationships between the quantity, toxicity, and compositional profile of dioxin/furan compounds (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in estuarine sediment and in the blue crab (Callinectes sapidus). Sediment and blue crab samples were collected in three small urban estuaries that are in relatively close proximity to each other. Results show that differences between PCDD/F and DL-PCB mass concentrations and total toxic equivalents (TEQ) toxicity in sediments of the three estuaries are reflected in those of the blue crab. TEQs are higher in the hepatopancreas of the crabs than in the sediment, but the concentration factor is inversely proportional to the TEQ in the sediments. Congener profiles in the crabs are systematically different from those in the sediments, and the difference is more pronounced for PCDD/Fs than for DL-PCBs, possibly due to differences in metabolization rates. Compared with sediment profiles, more lesser-chlorinated PCDD/Fs that have higher TEFs accumulate in crab hepatopancreas. This selective bioaccumulation of PCDD/Fs results in a TEQ augmentation in crab hepatopancreas compared with sediments. The bioaccumulation in the blue crab is also selective for PCDD/Fs over DL-PCBs. ?? 2011 Springer Science+Business Media B.V.

Utilization of waste crab shell (Scylla serrata) as a catalyst in palm olein transesterification.

PubMed

Boey, Peng-Lim; Maniam, Gaanty Pragas; Hamid, Shafida Abd

2009-01-01

Aquaculture activity has increased the population of crab, hence increasing the generation of related wastes, particularly the shell. In addition, the number of molting process in crabs compounds further the amount of waste shell generated. As such, in the present work, the application of the waste crab shell as a source of CaO in transesterification of palm olein to biodiesel (methyl ester) was investigated. Preliminary XRD results revealed that thermally activated crab shell contains mainly CaO. Parametric study has been investigated and optimal conditions were found to be methanol/oil mass ratio, 0.5:1; catalyst amount, 4 wt. %; and reaction temperature, 338 K. As compared to laboratory CaO, the catalyst from waste crab shell performs well, thus creating another low-cost catalyst source for producing biodiesel as well as adding value to the waste crab shell. Reusability of crab shell CaO has also been studied and the outcome confirmed that the catalyst is capable to be reutilized up to 11 times, without any major deterioration.

Symbiosis of sea anemones and hermit crabs: different resource utilization patterns in the Aegean Sea

NASA Astrophysics Data System (ADS)

Vafeiadou, Anna-Maria; Antoniadou, Chryssanthi; Chintiroglou, Chariton

2012-09-01

The small-scale distribution and resource utilization patterns of hermit crabs living in symbiosis with sea anemones were investigated in the Aegean Sea. Four hermit crab species, occupying shells of nine gastropod species, were found in symbiosis with the sea anemone Calliactis parasitica. Shell resource utilization patterns varied among hermit crabs, with Dardanus species utilizing a wide variety of shells. The size structure of hermit crab populations also affected shell resource utilization, with small-sized individuals inhabiting a larger variety of shells. Sea anemone utilization patterns varied both among hermit crab species and among residence shells, with larger crabs and shells hosting an increased abundance and biomass of C. parasitica. The examined biometric relationships suggested that small-sized crabs carry, proportionally to their weight, heavier shells and increased anemone biomass than larger ones. Exceptions to the above patterns are related either to local resource availability or to other environmental factors.

Inactivation of Paragonimus westermani metacercariae in soy sauce-marinated and frozen freshwater crabs.

PubMed

Kim, Tae Im; Oh, Se-Ra; Dai, Fuhong; Yang, Hyun-Jong; Ha, Sang-Do; Hong, Sung-Jong

2017-03-01

Soy sauce-marinated freshwater crabs (Eriocheir japonicus) are a source of human paragonimiasis. The viability of Paragonimus westermani metacercariae (PwMc) in marinated crabs was investigated in an experimental setting. The PwMc collected from freshwater crayfish were inoculated into freshwater crabs, which were then frozen or marinated in soy sauce. All PwMc in the freshwater crabs were inactivated after freezing for 48 h at -20 °C and after freezing for 12 h at -40 °C. After marinating for 32 days, the survival rate of PwMc in 5% NaCl soy sauce was 50%, in 7.5% NaCl soy sauce it was 33.3%, and in 10.0% NaCl soy sauce it was 31.3%. When marinated for 64 days, all PwMc were inactivated in all experimental groups. These results revealed that freezing and soy sauce marination were detrimental to the survival of PwMc in freshwater crabs. Specifically, freezing crabs for more than 48 h or soaking them in soy sauce containing at least 5.0% NaCl for 64 days can inactivate PwMc. These results can inform the production of the traditional Korean soy sauce-marinated freshwater crabs known as gejang.

CRABS IN CRISIS:BIOGEOGRAPHIC DISTRIBUTIONS, ABUNDANCES, AND VULNERABILITIES TO CLIMATE CHANGE OF BRACHYURAN AND LITHODID CRABS FROM THE GULF OF CALIFORNIA TO THE BEAUFORT SEA

EPA Science Inventory

To predict the relative vulnerability of near-coastal species to climate change we analyzed the biogeographic and abundance patterns of the brachyuran or ‘True’ crabs (n=368) and lithodid or ‘King’ crabs (n=20) that are found in the twelve MEOW (“Mar...

EVOLUTION OF THE CRAB NEBULA IN A LOW ENERGY SUPERNOVA

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

Yang, Haifeng; Chevalier, Roger A., E-mail: hy4px@virginia.edu, E-mail: rac5x@virginia.edu

The nature of the supernova leading to the Crab Nebula has long been controversial because of the low energy that is present in the observed nebula. One possibility is that there is significant energy in extended fast material around the Crab but searches for such material have not led to detections. An electron capture supernova model can plausibly account for the low energy and the observed abundances in the Crab. Here, we examine the evolution of the Crab pulsar wind nebula inside a freely expanding supernova and find that the observed properties are most consistent with a low energy event.more » Both the velocity and radius of the shell material, and the amount of gas swept up by the pulsar wind point to a low explosion energy (∼10{sup 50} erg). We do not favor a model in which circumstellar interaction powers the supernova luminosity near maximum light because the required mass would limit the freely expanding ejecta.« less

Current status and clinical association of beta-catenin with juvenile nasopharyngeal angiofibroma.

PubMed

Mishra, A; Singh, V; Verma, V; Pandey, S; Trivedi, R; Singh, H P; Kumar, S; Dwivedi, R C; Mishra, S C

2016-10-01

A possible role of the APC/beta-catenin pathway in the pathogenesis of sporadic juvenile nasopharyngeal angiofibroma has been suggested. This paper presents its current status and clinical association in our patients. A prospective observational study was conducted at King George Medical University and Central Drug Research Institute, in Lucknow, India. Western blot analysis was undertaken in 16 cases to examine beta-catenin expression. The clinical details were recorded along with follow up observations, to determine associations. Up-regulation of beta-catenin expression was seen in 69 per cent of cases. The clinical variables did not reveal significant differences between patients with extremes of expression (extreme under- vs over-expression). However, absent expression was shown exclusively in young adults aged over 18 years, while enhanced expression was associated with an altered facial profile. Although a beta-catenin association was seen in a subset of our sporadic juvenile nasopharyngeal angiofibroma cases, its expression was not homogeneous. This is in contrast to the Western literature that suggests a universal (homogenous) enhanced expression in the majority. Hence, further research is required to better define its molecular cascade.

Effects of tributyltin exposure in hermit crabs: Clibanarius vittatus as a model.

PubMed

Sant'Anna, Bruno Sampaio; Santos, Dayana Moscardi Dos; Marchi, Mary Rosa Rodrigues de; Zara, Fernando José; Turra, Alexander

2012-03-01

Tributyltin (TBT) contamination affects the reproductive system of many species of invertebrates worldwide. The present study was designed to evaluate the effects of exposure to TBT pollution on the reproduction of the hermit crab Clibanarius vittatus. An orthogonal experiment was designed with two treatments: contamination (with or without TBT in the food) and crab sex (males and females). The animals were reared in the laboratory for nine months, and macroscopic and histological analyses of reproductive organs were carried out after the end of the experiment. Tributyltin was recorded in exposed crabs, but no morphological alterations were detected in the gonads of males, regardless of whether they were exposed to TBT. In contrast, females exposed to TBT displayed disorganization and atrophy of their ovaries, thus directly affecting reproduction in this hermit crab species. This effect observed in female hermit crabs may harm populations located in harbor regions, where TBT concentration is high, even after the worldwide TBT ban. Copyright © 2011 SETAC.

Behavioral thermoregulation in Hemigrapsus nudus, the amphibious purple shore crab.

PubMed

McGaw, I J

2003-02-01

The thermoregulatory behavior of Hemigrapsus nudus, the amphibious purple shore crab, was examined in both aquatic and aerial environments. Crabs warmed and cooled more rapidly in water than in air. Acclimation in water of 16 degrees C (summer temperatures) raised the critical thermal maximum temperature (CTMax); acclimation in water of 10 degrees C (winter temperatures) lowered the critical thermal minimum temperature (CTMin). The changes occurred in both water and air. However, these survival regimes did not reflect the thermal preferences of the animals. In water, the thermal preference of crabs acclimated to 16 degrees C was 14.6 degrees C, and they avoided water warmer than 25.5 degrees C. These values were significantly lower than those of the crabs acclimated to 10 degrees C; these animals demonstrated temperature preferences for water that was 17 degrees C, and they avoided water that was warmer than 26.9 degrees C. This temperature preference was also exhibited in air, where 10 degrees C acclimated crabs exited from under rocks at a temperature that was 3.2 degrees C higher than that at which the 16 degrees C acclimated animals responded. This behavioral pattern was possibly due to a decreased thermal tolerance of 16 degrees C acclimated crabs, related with the molting process. H. nudus was better able to survive prolonged exposure to cold temperatures than to warm temperatures, and there was a trend towards lower exit temperatures with the lower acclimation (10 degrees C) temperature. Using a complex series of behaviors, the crabs were able to precisely control body temperature independent of the medium, by shuttling between air and water. The time spent in either air or water was influenced more strongly by the temperature than by the medium. In the field, this species may experience ranges in temperatures of up to 20 degrees C; however, it is able to utilize thermal microhabitats underneath rocks to maintain its body temperature within fairly narrow

NASA Beechcraft KingAir #801 in flight

NASA Technical Reports Server (NTRS)

1998-01-01

NASA 801 Beechcraft Beech Super KingAir in flight. The Beechcraft Beech 200 Super KingAir aircraft N7NA, known as NASA 7, has been a support aircraft for many years, flying 'shuttle' missions to Ames Research Center. It once flew from the Jet Propulsion Laboratory and back each day but now (2001) flies between the Dryden Flight Research Center and Ames. A second Beechcraft Beech 200 Super King Air, N701NA, redesignated N801NA, transferred to Dryden on 3 Oct. 1997 and is used for research missions but substitutes for NASA 7 on shuttle missions when NASA 7 is not available.

Dragon-Kings, Black-Swans and Prediction (Invited)

NASA Astrophysics Data System (ADS)

Sornette, D.

2010-12-01

Extreme fluctuations or events are often associated with power law statistics. Indeed, it is a popular belief that "wild randomness'' is deeply associated with distributions with power law tails characterized by small exponents. In other words, power law tails are often seen as the epitome of extreme events (the "Black Swan'' story). Here, we document in very different systems that there is life beyond power law tails: power laws can be superseded by "dragon-kings'', monster events that occur beyond (or changing) the power law tail. Dragon-kings reveal hidden mechanisms that are only transiently active and that amplify the normal fluctuations (often described by the power laws of the normal regime). The goal of this lecture is to catalyze the interest of the community of geophysicists across all fields of geosciences so that the "invisible gorilla" fallacy may be avoided. Our own research illustrates that new statistics or representation of data are often necessary to identify dragon-kings, with strategies guided by the underlying mechanisms. Paradoxically, the monsters may be ignored or hidden by the use of inappropriate analysis or statistical tools that amount to cut a mamooth in small pieces, so as to lead to the incorrect belief that only mice exist. In order to stimulate further research, we will document and discuss the dragon-king phenomenon on the statistics of financial losses, economic geography, hydrodynamic turbulence, mechanical ruptures, avalanches in complex heterogeneous media, earthquakes, and epileptic seizures. The special status of dragon-kings open a new research program on their predictability, based on the fact that they belong to a different class of their own and express specific mechanisms amplifying the normal dynamics via positive feedbacks. We will present evidence of these claims for the predictions of material rupture, financial crashes and epileptic seizures. As a bonus, a few remarks will be offered at the end on how the dragon-king

Space Movie Reveals Shocking Secrets Of The Crab Pulsa

NASA Astrophysics Data System (ADS)

2002-09-01

Just when it seemed like the summer movie season had ended, two of NASA's Great Observatories have produced their own action movie. Multiple observations made over several months with NASA's Chandra X-ray Observatory and the Hubble Space Telescope captured the spectacle of matter and antimatter propelled to near the speed of light by the Crab pulsar, a rapidly rotating neutron star the size of Manhattan. "Through this movie, the Crab Nebula has come to life," said Jeff Hester of Arizona State University in Tempe, lead author of a paper in the September 20th issue of The Astrophysical Journal Letters. "We can see how this awesome cosmic generator actually works." The Crab was first observed by Chinese astronomers in 1054 A.D. and has since become one of the most studied objects in the sky. By combining the power of both Chandra and Hubble, the movie reveals features never seen in still images. By understanding the Crab, astronomers hope to unlock the secrets of how similar objects across the universe are powered. Crab Nebula Composite Image Crab Nebula Composite Image Bright wisps can be seen moving outward at half the speed of light to form an expanding ring that is visible in both X-ray and optical images. These wisps appear to originate from a shock wave that shows up as an inner X-ray ring. This ring consists of about two dozen knots that form, brighten and fade, jitter around, and occasionally undergo outbursts that give rise to expanding clouds of particles, but remain in roughly the same location. "These data leave little doubt that the inner X-ray ring is the location of the shock wave that turns the high-speed wind from the pulsar into extremely energetic particles," said Koji Mori of Penn State University in University Park, a coauthor of the paper. Another dramatic feature of the movie is a turbulent jet that lies perpendicular to the inner and outer rings. Violent internal motions are obvious, as is a slow motion outward into the surrounding nebula of

40 CFR 408.50 - Applicability; description of the remote Alaskan crab meat processing subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... remote Alaskan crab meat processing subcategory. 408.50 Section 408.50 Protection of Environment... PROCESSING POINT SOURCE CATEGORY Remote Alaskan Crab Meat Processing Subcategory § 408.50 Applicability; description of the remote Alaskan crab meat processing subcategory. The provisions of this subpart are...

40 CFR 408.50 - Applicability; description of the remote Alaskan crab meat processing subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... remote Alaskan crab meat processing subcategory. 408.50 Section 408.50 Protection of Environment... PROCESSING POINT SOURCE CATEGORY Remote Alaskan Crab Meat Processing Subcategory § 408.50 Applicability; description of the remote Alaskan crab meat processing subcategory. The provisions of this subpart are...

Design and prototyping of HL-LHC double quarter wave crab cavities for SPS test

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

Verdu-Andres, S.; Skaritka, J.; Wu, Q.

2015-05-03

The LHC high luminosity project envisages the use of the crabbing technique for increasing and levelling the LHC luminosity. Double Quarter Wave (DQW) resonators are compact cavities especially designed to meet the technical and performance requirements for LHC beam crabbing. Two DQW crab cavities are under fabrication and will be tested with beam in the Super Proton Synchrotron (SPS) at CERN by 2017. This paper describes the design and prototyping of the DQW crab cavities for the SPS test.

Folk classification of the crabs and swimming crabs (Crustacea – Brachyura) of the Mamanguape river estuary, Northeastern – Brazil

PubMed Central

Ferreira, Emmanoela N; da S Mourão, José; Rocha, Pollyana D; Nascimento, Douglas M; da S Q Bezerra, Dandara Monalisa Mariz

2009-01-01

Background Folk taxonomy is a sub-area of ethnobiology that study the way of how traditional communities classify, identify and name their natural resources. The work present was undertaken in two traditional communities (Barra de Mamanguape and Tramataia). The objective of this study was investigate the ethnobiological classification of the local crabs and swimming crabs used by the crustaceous gatherers of the Mamanguape River Estuary (MRE), Paraíba State, Brazil. Methods The methodology used here involved a combination of qualitative methods (open interviews, semi-structured interviews, direct observations, guided tours, surveys, and interviews in synchronic and diachronic situations that crossed-checked and repeated identifications) and quantitative methods (Venn diagram). A total of 32 men and women were interviewed in the two communities. Specimens of the local crustaceans were collected and identified by the harvesters themselves, subsequently fixed in formalin, conserved in 70% ethyl alcohol, identified using appropriate specialized literature, and then deposited in the laboratory of the Zoology Department of the University State of Paraiba. Results The crustaceous gatherers we studied were observed to group crustaceans according to their similarities and differences, producing a hierarchical classification system containing four levels of decreasing taxonomic order: unique beginner, life-form, generic, and specific. A sequential and/or semantic system classification system that is used to classify the ontogeny of the female swimming crab was also identified. Of the nine folk generics identified, 44.5% were monotypic. 55.5% were polytypic and were subdivided into 15 folk specifics. An identification key was elaborated with the data obtained about the folk polytypics generics. Conclusion The detailed knowledge concerning the crabs and swimming crabs revealed by the MRE crustaceous gatherers demonstrates that these people detain a vast knowledge concerning

Ontogeny of decapod crustacean hemocyanin: effects of temperature and nutrition.

PubMed

Terwilliger, N; Dumler, K

2001-03-01

Hemocyanin is present throughout the decapod crustacean's life, usually as one-hexamer and two-hexamer oligomers. Hemocyanins of some decapod crustaceans undergo changes in subunit composition and oxygen affinity during development. Maternal hemocyanin is taken up from the hemolymph via endocytosis by the oocyte. Embryo hemocyanin differs in subunit composition from hemocyanin of oocyte and adult crab and may represent the onset of hemocyanin synthesis. Complex changes in expression of hemocyanin subunits occur through megalopa and early juvenile stages of the crab Cancer magister, culminating in the pattern of adult hemocyanin. The influences of food availability and temperature on development, growth and hemocyanin ontogeny in early juvenile C. magister have been studied. Crabs were raised in warm or cold sea water and fed high or low levels of food for 6 months. While intermolt period was shorter in crabs fed high food levels, especially those raised in warm water, crabs reared in cold water with high food levels attained the largest sizes. Thus increased food availability affects growth more than increased temperature. Adult hemocyanin appeared at about the same number of weeks after the start of the experiment for crabs in the warm water/high food, warm water/low food and cold water/high food groups, even though warm water/low food crabs had molted fewer times. Crabs in the cold water/low food group expressed adult hemocyanin much later than the other groups. Molt stage and maturation from juvenile to adult are not absolutely coupled, and food availability has a greater influence than temperature on hemocyanin ontogeny.

Sexual selection and the physiological consequences of habitat choice by a fiddler crab.

PubMed

Allen, Bengt J; Levinton, Jeffrey S

2014-09-01

In mid-Atlantic salt marshes, reproductively active male sand fiddler crabs, Uca pugilator, use a single greatly enlarged major claw as both a weapon to defend specialized breeding burrows from other males and an ornament to attract females for mating. During the summer breeding season, females strongly prefer to mate with males controlling burrows in open areas high on the shore. Food availability decreases while temperature and desiccation stress increase with increasing shore height, suggesting that the timing and location of fiddler crab mating activity may result in a potential trade-off between reproductive success and physiological condition for male crabs. We compared thermal preferences in laboratory choice experiments to body temperatures of models and living crabs in the field and found that from the perspective of a fiddler crab, the thermal environment of the mating area is quite harsh relative to other marsh microhabitats. High temperatures significantly constrained fiddler crab activity on the marsh surface, a disadvantage heightened by strongly reduced food availability in the breeding area. Nevertheless, when the chance of successfully acquiring a mate was high, males accepted a higher body temperature (and concomitantly higher metabolic and water loss rates) than when the chances of mating were low. Likewise, experimentally lowering costs by adding food and reducing thermal stress in situ increased fiddler crab waving display levels significantly. Our data suggest that fiddler crabs can mitigate potential life history trade-offs by tuning their behavior in response to the magnitude of both energetic and non-energetic costs and benefits.

CMS distributed data analysis with CRAB3

NASA Astrophysics Data System (ADS)

Mascheroni, M.; Balcas, J.; Belforte, S.; Bockelman, B. P.; Hernandez, J. M.; Ciangottini, D.; Konstantinov, P. B.; Silva, J. M. D.; Ali, M. A. B. M.; Melo, A. M.; Riahi, H.; Tanasijczuk, A. J.; Yusli, M. N. B.; Wolf, M.; Woodard, A. E.; Vaandering, E.

2015-12-01

The CMS Remote Analysis Builder (CRAB) is a distributed workflow management tool which facilitates analysis tasks by isolating users from the technical details of the Grid infrastructure. Throughout LHC Run 1, CRAB has been successfully employed by an average of 350 distinct users each week executing about 200,000 jobs per day. CRAB has been significantly upgraded in order to face the new challenges posed by LHC Run 2. Components of the new system include 1) a lightweight client, 2) a central primary server which communicates with the clients through a REST interface, 3) secondary servers which manage user analysis tasks and submit jobs to the CMS resource provisioning system, and 4) a central service to asynchronously move user data from temporary storage in the execution site to the desired storage location. The new system improves the robustness, scalability and sustainability of the service. Here we provide an overview of the new system, operation, and user support, report on its current status, and identify lessons learned from the commissioning phase and production roll-out.

CMS distributed data analysis with CRAB3

DOE PAGES

Mascheroni, M.; Balcas, J.; Belforte, S.; ...

2015-12-23

The CMS Remote Analysis Builder (CRAB) is a distributed workflow management tool which facilitates analysis tasks by isolating users from the technical details of the Grid infrastructure. Throughout LHC Run 1, CRAB has been successfully employed by an average of 350 distinct users each week executing about 200,000 jobs per day.CRAB has been significantly upgraded in order to face the new challenges posed by LHC Run 2. Components of the new system include 1) a lightweight client, 2) a central primary server which communicates with the clients through a REST interface, 3) secondary servers which manage user analysis tasks andmore » submit jobs to the CMS resource provisioning system, and 4) a central service to asynchronously move user data from temporary storage in the execution site to the desired storage location. Furthermore, the new system improves the robustness, scalability and sustainability of the service.Here we provide an overview of the new system, operation, and user support, report on its current status, and identify lessons learned from the commissioning phase and production roll-out.« less

Growth, reproduction & population structure of the freshwater crab Sinopotamon yangtsekiense bott, 1967, from Zhejiang, China

NASA Astrophysics Data System (ADS)

Chen, Tao; Lai, Wei; Du, Nan-Shan

1994-03-01

Monthly investigations were mae on the population of Chinese freshwater crab, Sinopotamon yangtsekiense Bott, 1967 from April, 1984 to March, 1985. The data on 4413 specimens show that the growth was affected mainly by temperature. During the April to November growth period, the crabs' major development occurred from June through October. One year was required for a fine white oocyte to develop into a mature egg. The reproduction period was June October. Females bearing eggs were taken from June August, and crabs with young were found from July October. The females reproduced once a year but could for more than one year. The number of eggs carried by a female varied greatly according to the size of the crab, ranging from 30 to 100 eggs. New-born crabs become mature after 1 2 years. The sex ratio was approximately 1∶1 in the overall population. However, the larger crabs are predominantly male. The age distribution of S. yangtsekinese was estimated from size frequency histograms. There were more adult crabs (over 70%) from June to October and more immature crabs (over 50%) from November to May.

Ocean Acidification Affects Hemocyte Physiology in the Tanner Crab (Chionoecetes bairdi)

PubMed Central

Meseck, Shannon L.; Alix, Jennifer H.; Swiney, Katherine M.; Long, W. Christopher; Wikfors, Gary H.; Foy, Robert J.

2016-01-01

We used flow cytometry to determine if there would be a difference in hematology, selected immune functions, and hemocyte pH (pHi), under two different, future ocean acidification scenarios (pH = 7.50, 7.80) compared to current conditions (pH = 8.09) for Chionoecetes bairdi, Tanner crab. Hemocytes were analyzed after adult Tanner crabs were held for two years under continuous exposure to acidified ocean water. Total counts of hemocytes did not vary among control and experimental treatments; however, there were significantly greater number of dead, circulating hemocytes in crabs held at the lowest pH treatment. Phagocytosis of fluorescent microbeads by hemocytes was greatest at the lowest pH treatment. These results suggest that hemocytes were dying, likely by apoptosis, at a rate faster than upregulated phagocytosis was able to remove moribund cells from circulation at the lowest pH. Crab hemolymph pH (pHe) averaged 8.09 and did not vary among pH treatments. There was no significant difference in internal pH (pHi) within hyalinocytes among pH treatments and the mean pHi (7.26) was lower than the mean pHe. In contrast, there were significant differences among treatments in pHi of the semi-granular+granular cells. Control crabs had the highest mean semi-granular+granular pHi compared to the lowest pH treatment. As physiological hemocyte functions changed from ambient conditions, interactions with the number of eggs in the second clutch, percentage of viable eggs, and calcium concentration in the adult crab shell was observed. This suggested that the energetic costs of responding to ocean acidification and maintaining defense mechanisms in Tanner crab may divert energy from other physiological processes, such as reproduction. PMID:26859148

Colorectal carcinoma that afflicted King Jehoram.

PubMed

Liubov Louba, Ben-Noun

2004-12-01

This research uses the tools of modern medical science to examine the ancient descriptions of the symptoms suffered by King Jehoram who was affected by some disease. The Biblical texts were examined, and passages relating to the disease that afflicted King Jehoram, who ruled in Jerusalem 843-851 B.C., were closely studied. We have not included any commentaries, but referred only to the words of the Bible exactly as written. The Passages ''...the Lord smote him in his bowels with an incurable disease in the process of time, after the end of two years, his bowels fell out by reason of his sickness: so he died of sore diseases'' indicate that the King suffered from some kind of disease which affected his bowels. Among the various diseases which may be associated with prolapse of the bowel, colorectal carcinoma is the most acceptable. It seems that the colorectal carcinoma was poorly differentiated, invaded perirectal adipose tissue, blood vessels, and/or lymphatic vessels, and/or perineural areas, was lymph node positive and reached the 4th stage with the spread of metastases to the distal organs. Viewed by a modern physician, the story of King Jehoram unfolds as possibly the earliest description of a patient afflicted by colorectal carcinoma.

Lesbian drag kings and the feminine embodiment of the masculine.

PubMed

Schacht, Steven P

2002-01-01

Part of an ongoing ethnography of an imperial sovereign court I am undertaking, this chapter explores the world of the lesbian drag king and the gendered performance she undertakes in this realm. Taking a relational, situational approach to understanding gender, the lesbian drag queen of the court is also examined in terms of how "her" image and actions give gendered meaning and confer import to the lesbian drag king. Note is also made of lesbian court members' often contradictory gendered relationships with the gay men in this setting: gay drag kings and gay drag kings. Although embodying a masculine persona in image and action has enabled some lesbian drag kings to successfully challenge the often sexist actions and reign of the gay men of the court, it has also resulted in some lesbian drag queens being subordinated in the process. Thus, as much as lesbian drag kings subvert existing gender hierarchies they also sometimes recreate them in the pursuit of situational power.

Juvenile angiofibroma

MedlinePlus

Nasal tumor; Angiofibroma - juvenile; Benign nasal tumor; Juvenile nasal angiofibroma; JNA ... Juvenile angiofibroma is not very common. It is most often found in adolescent boys. The tumor contains many blood ...

50 CFR 679.54 - Release of observer data to the public.

Code of Federal Regulations, 2013 CFR

2013-10-01

... round weight of incidentally caught halibut or Pacific herring to the total round weight of groundfish in sampled catch. (4) The ratio of number of king crab or C. bairdi Tanner crab to the total round... of Chinook salmon to the total round weight of groundfish. (vii) The ratio of the number of other...

50 CFR 679.54 - Release of observer data to the public.

Code of Federal Regulations, 2014 CFR

2014-10-01

... round weight of incidentally caught halibut or Pacific herring to the total round weight of groundfish in sampled catch. (4) The ratio of number of king crab or C. bairdi Tanner crab to the total round... of Chinook salmon to the total round weight of groundfish. (vii) The ratio of the number of other...

Sidewalk data in King County's urban growth boundary.

DOT National Transportation Integrated Search

2013-06-01

This report describes the development of geospatial sidewalk data for the King County Urban : Growth Area. Prior to the development of this data set, sidewalk data in King County were limited to : select jurisdictions and existed in multiple, sometim...

Filtering out parasites: sand crabs (Lepidopa benedicti) are infected by more parasites than sympatric mole crabs (Emerita benedicti)

PubMed Central

2017-01-01

Two digging decapod crustaceans, the sand crab species Lepidopa benedicti and the mole crab species Emerita benedicti, both live in the swash zone of fine sand beaches. They were examined for two parasites that infect decapod crustaceans in the region, an unidentified nematode previously shown to infect L. benedicti, and cestode tapeworm larvae, Polypocephalus sp., previously shown to infect shrimp (Litopenaeus setiferus). Lepidopa benedicti were almost always infected with both parasite species, while E. benedicti were rarely infected with either parasite species. This difference in infection pattern suggests that tapeworms are ingested during sediment feeding in L. benedicti, which E. benedicti avoid by filter feeding. Larger L. benedicti had more Polypocephalus sp. larvae. The thoracic ganglia, which make up the largest proportion of neural tissue, contained the largest numbers of Polypocephalus sp. larvae. Intensity of Polypocephalus sp. infection was not correlated with how long L. benedicti remained above sand in behavioural tests, suggesting that Polypocephalus sp. do not manipulate the sand crabs in a way that facilitates trophic transmission of the parasite. Litopenaeus setiferus may be a primary host for Polypocephalus sp., and L. benedict may be a secondary, auxiliary host. PMID:28951818

Juveniles in court.

PubMed

Soulier, Matthew F; Scott, Charles L

2010-01-01

Nineteenth-century American reformers were concerned about the influence of immaturity and development in juvenile offenses. They responded to their delinquent youths through the creation of juvenile courts. This early American juvenile justice system sought to treat children as different from adults and to rehabilitate wayward youths through the state's assumption of a parental role. Although these rehabilitative goals were never fully realized, the field of American child psychiatry was spawned from these efforts on behalf of delinquent youths. Early child psychiatrists began by caring for juvenile offenders. The function of a child psychiatrist with juvenile delinquents expanded beyond strictly rehabilitation, however, as juvenile courts evolved to resemble criminal adult courts-due to landmark Supreme Court decisions and also juvenile legislation between 1966 and 1975. In response to dramatically increased juvenile violence and delinquency rates in the 1980s, juvenile justice became more retributional, and society was forced to confront issues such as capital punishment for juveniles, their transfer to adult courts, and their competency to stand trial. In the modern juvenile court, child psychiatrists are often asked to participate in the consideration of such issues because of their expertise in development. In that context we review the role of psychiatrists in assisting juvenile courts.

Mitochondrial gene rearrangements confirm the parallel evolution of the crab-like form.

PubMed Central

Morrison, C L; Harvey, A W; Lavery, S; Tieu, K; Huang, Y; Cunningham, C W

2002-01-01

The repeated appearance of strikingly similar crab-like forms in independent decapod crustacean lineages represents a remarkable case of parallel evolution. Uncertainty surrounding the phylogenetic relationships among crab-like lineages has hampered evolutionary studies. As is often the case, aligned DNA sequences by themselves were unable to fully resolve these relationships. Four nested mitochondrial gene rearrangements--including one of the few reported movements of an arthropod protein-coding gene--are congruent with the DNA phylogeny and help to resolve a crucial node. A phylogenetic analysis of DNA sequences, and gene rearrangements, supported five independent origins of the crab-like form, and suggests that the evolution of the crab-like form may be irreversible. This result supports the utility of mitochondrial gene rearrangements in phylogenetic reconstruction. PMID:11886621

The Influence of Diet Composition on Fitness of the Blue Crab, Callinectes sapidus.

PubMed

Belgrad, Benjamin A; Griffen, Blaine D

2016-01-01

The physiological condition and fecundity of an organism is frequently controlled by diet. As changes in environmental conditions often cause organisms to alter their foraging behavior, a comprehensive understanding of how diet influences the fitness of an individual is central to predicting the effect of environmental change on population dynamics. We experimentally manipulated the diet of the economically and ecologically important blue crab, Callinectes sapidus, to approximate the effects of a dietary shift from primarily animal to plant tissue, a phenomenon commonly documented in crabs. Crabs whose diet consisted exclusively of animal tissue had markedly lower mortality and consumed substantially more food than crabs whose diet consisted exclusively of seaweed. The quantity of food consumed had a significant positive influence on reproductive effort and long-term energy stores. Additionally, seaweed diets produced a three-fold decrease in hepatopancreas lipid content and a simultaneous two-fold increase in crab aggression when compared to an animal diet. Our results reveal that the consumption of animal tissue substantially enhanced C. sapidus fitness, and suggest that a dietary shift to plant tissue may reduce crab population growth by decreasing fecundity as well as increasing mortality. This study has implications for C. sapidus fisheries.

Infestation of parasitic rhizocephalan barnacles Sacculina beauforti (Cirripedia, Rhizocephala) in edible mud crab, Scylla olivacea

PubMed Central

2017-01-01

Screening of mud crab genus Scylla was conducted in four locations (Marudu Bay, Lundu, Taiping, Setiu) representing Malaysia. Scylla olivacea with abnormal primary and secondary sexual characters were prevalent (approximately 42.27% of the local screened S. olivacea population) in Marudu Bay, Sabah. A total of six different types of abnormalities were described. Crabs with type 1 and type 3 were immature males, type 2 and type 4 were mature males, type 5 were immature females and type 6 were mature females. The abdomen of all crabs with abnormalities were dented on both sides along the abdomen’s middle line. Abnormal crabs showed significant variation in their size, weight, abdomen width and/or gonopod or pleopod length compared to normal individuals. The mean body weight of abnormal crabs (type 1–5) were higher than normal crabs with smaller body size, while females with type 6 abnormality were always heavier than the normal counterparts at any given size. Sacculinid’s externa were observed in the abdomen of crabs with type 4 and type 6 abnormalities. The presence of embryos within the externa and subsequent molecular analysis of partial mitochondrial COI region confirmed the rhizocephalan parasite as Sacculina beauforti. Future in-depth descriptions of the life cycle and characteristics of S. beauforti are recommended as it involves a commercially important edible crab species and the effect on human health from the consumption of crabs is of crucial concern. PMID:28674645

Gout: A Disease of Kings.

PubMed

Tang, Sydney C W

2018-01-01

As a disease of kings, and the king of diseases, gout is one of the oldest joint diseases known to humans. First described as far back as 2640 B.C., gout is still the most common form of inflammatory arthritis haunting humans in the 21st century. The disease is caused by the chronic elevation of serum uric acid levels above the saturation point for monosodium urate crystal formation. Its incidence is progressively rising even today, but there are also regional and ethnic variations. Finally, the role of genetics is only beginning to be unraveled. © 2018 S. Karger AG, Basel.

The Newest Monument: The Martin Luther King, Jr. National Memorial

ERIC Educational Resources Information Center

Social Studies and the Young Learner, 2011

2011-01-01

This article features the newest monument, the Martin Luther King, Jr. National Memorial. The memorial on the National Mall in Washington, D.C., honoring Dr. Martin Luther King, Jr. will be an engaging landscape experience to convey four fundamental and recurring themes throughout Dr. King's life--democracy, justice, hope, and love. Natural…

Gastrointestinal helminths of Gentoo penguins (Pygoscelis papua) from Stranger Point, 25 de Mayo/King George Island, Antarctica.

PubMed

Diaz, Julia Inés; Fusaro, Bruno; Longarzo, Lucrecia; Coria, Néstor Rubén; Vidal, Virginia; Jerez, Silvia; Ortiz, Juana; Barbosa, Andrés

2013-05-01

The aim of this work is to contribute to the knowledge of gastrointestinal parasites of the Gentoo penguin (Pygoscelis papua) from 25 de Mayo/King George Island (South Shetlands, Antarctica). Gastrointestinal tracts of 37 fresh dead individuals (21 chicks, 10 juveniles, and 6 adults) were collected from December 2006 to February 2012 and examined for macroparasites. Four adult parasite species were found: one Cestoda species (Parorchites zederi), two Nematoda species (Stegophorus macronectes and Tetrameres wetzeli), and one Acanthocephalan (Corynosoma shackletoni). Two species of immature acanthocephalans, Corynosoma hamanni and Corynosoma bullosum, were found in a single host. This is the first record of Tetrameres wetzeli in Gentoo penguins. The low parasite richness observed could be related to the stenophagic and pelagic diet of this host species which feeds almost exclusively on krill.

Rare Death Via Histamine Poisoning Following Crab Consumption: A Case Report.

PubMed

Yu, Yang; Wang, Ping; Bian, Ligong; Hong, Shijun

2018-05-01

Histamine poisoning (scombroid food poisoning) is a toxicity syndrome that results from eating spoiled fish. To date, however, few poisoning (or mortality) cases have been reported in relation to crab consumption. Here, we describe a very uncommon case in which a 37-year-old woman and her 14-year-old son ate cooked crabs (Scylla serrata), resulting in the death of the female. Samples of vomitus, food residue, liver tissue, gastric content, intestinal content, and cardiac blood were analyzed by high-performance liquid chromatography. Toxicological analysis revealed that histamine concentrations were very high in the cooked crab (47.08 mg/100 g) and intestinal content (22.54 mg/100 g). Comparing our toxicological results, police investigations, and family member statements, it can be assumed that the decedent ingested spoiled crabs, and by excluding other causes of death, lethal intoxication with histamine poisoning was confirmed. © 2017 American Academy of Forensic Sciences.

Mode of action of dopamine in inducing hyperglycemia in the fresh water edible crab, Oziothelphusa senex senex.

PubMed

Swetha, Ch; Sainath, S B; Reddy, P Sreenivasula

2014-11-01

The objective of this study was to investigate the mode of action of dopamine in regulating hemolymph sugar level in the fresh water edible crab, Oziothelphusa senex senex. Injection of dopamine produced hyperglycemia in a dose-dependent manner in intact crabs but not in eyestalkless crabs. Administration of dopamine resulted in a significant decrease in total carbohydrates and glycogen levels with a significant increase in glycogen phosphorylase activity levels in hepatopancreas and muscle of intact crabs, indicating dopamine-induced glycogenolysis resulting in hyperglycemia. Bilateral eyestalk ablation resulted in significant increase in the total carbohydrates and glycogen levels with a significant decrease in the activity levels of phosphorylase in the hepatopancreas and muscle of the crabs. Eyestalk ablation resulted in significant decrease in hemolymph hyperglycemic hormone levels. The levels of hyperglycemic hormone in the hemolymph of dopamine injected crabs were significantly higher than in control crabs. However, no significant changes in the levels of hemolymph hyperglycemic hormone and sugar and tissue carbohydrate and phosphorylase activity were observed in dopamine injected eyestalk ablated crabs when compared with eyestalk ablated crabs. These results support an earlier hypothesis in crustaceans that dopamine acts as a neurotransmitter and induces hyperglycemia by triggering the release of hyperglycemic hormone in the crab, O. senex senex. © 2014 Wiley Periodicals, Inc.

Movement patterns and trajectories of ovigerous blue crabs Callinectes sapidus during the spawning migration

NASA Astrophysics Data System (ADS)

Carr, Sarah D.; Tankersley, Richard A.; Hench, James L.; Forward, Richard B.; Luettich, Richard A.

2004-08-01

Female blue crabs ( Callinectes sapidus Rathbun) migrate from low salinity estuarine regions to high salinity regions near the ocean to release larvae. During this migration, ovigerous females use ebb-tide transport, a vertical migratory behavior in which they ascend into the water column during ebb tides, to move seaward to larval release areas. In order to determine the relationship of ebb-tide vertical migrations to local currents and the influence of these vertical migrations on the horizontal transport of blue crabs in the estuary, ovigerous females with mature embryos (˜1-3 days from hatching) were tracked near Beaufort Inlet, North Carolina (USA), in July and August 2001 and 2002. Crabs were tagged and tracked using ultrasonic telemetry, and currents near the crabs were measured simultaneously with a shipboard acoustic Doppler current profiler. During the two seasons, eight crabs were successfully tracked for periods ranging from 3.9-37.0 h and for distances ranging from 1.9-10.6 km. All crabs migrated seaward during the tracking periods. Crabs moved episodically during all tidal phases with periods of movement on the order of minutes to an hour. They moved with local currents in terms of both speed and direction during ebb tides, consistent with ebb-tide transport, and moved down-estuary (seaward) in opposition to local currents during flood tides. The percentage of time that crabs were active was higher during night ebb tides than during day ebb tides or flood tides and increased with increasing ebb-tide current speed. Mean migratory speeds were 0.11, 0.04, 0.08 and 0.02 m s -1 during night ebb, night flood, day ebb and day flood tides, respectively, and net migratory speeds were on the order of 5 km day -1. Due to the episodic nature of the crabs' movements, the total distances that crabs traveled during ebb tides ranged from 10-40% of the distances that passive particles could have traveled under the same conditions.

50 CFR Table 5 to Part 680 - Crab Size Codes

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 13 2012-10-01 2012-10-01 false Crab Size Codes 5 Table 5 to Part 680 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) SHELLFISH FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 680, Table 5 Table 5 to Part 680—Crab Size...

50 CFR Table 5 to Part 680 - Crab Size Codes

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Crab Size Codes 5 Table 5 to Part 680 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) SHELLFISH FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 680, Table 5 Table 5 to Part 680—Crab Size...

50 CFR Table 5 to Part 680 - Crab Size Codes

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 11 2011-10-01 2011-10-01 false Crab Size Codes 5 Table 5 to Part 680 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) SHELLFISH FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 680, Table 5 Table 5 to Part 680—Crab Size...

Detection of Paragonimus mexicanus (Trematoda) metacercariae in crabs from Oaxaca, Mexico.

PubMed

Vargas-Arzola, Jaime; Segura-Salvador, Aristeo; Reyes-Velasco, Leobardo; Díaz-Chiguer, Dylan L; Márquez-Navarro, Adrián; León-Avila, Gloria; Ibañez-Cervantes, Gabriela; Camacho, Alejandro D; Sánchez-Manzano, Rosa Ma; Nogueda-Torres, Benjamín

2014-09-01

Metacercariae of Paragonimus mexicanus were collected in crabs Tehuana guerreroensis (Rathbun, 1933) in the municipality of Putla, Oaxaca, Mexico. Metacercariae were found in 20.8% of the crabs collected, with an average of 1.9 metacercarie per crab. Stained metacercariae showed the specific characteristics of P. mexicanus by morphology and sequencing a fragment of the 28S ribosomal gene obtained by PCR. These findings reveal that T. guerreroensis is an intermediate host for P. mexicanus; this new report is relevant considering the potential risk of transmission in the states of Oaxaca and Guerrero, Mexico. Copyright © 2014 Elsevier B.V. All rights reserved.

76 FR 3819 - Martin Luther King, Jr., Federal Holiday, 2011

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-20

... changed the course of history. The Reverend Dr. Martin Luther King, Jr. devoted his life to the struggle for justice and equality, sowing seeds of hope for a day when all people might claim ``the riches of... celebrate the life and legacy of Dr. King. Dr. King guided us toward a mountaintop on which all Americans...

Juvenile Idiopathic Arthritis

MedlinePlus

... Is Juvenile Idiopathic Arthritis the same as Juvenile Rheumatoid Arthritis? Yes, Juvenile Idiopathic Arthritis (JIA) is a new ... of chronic inflammatory diseases that affect children. Juvenile Rheumatoid Arthritis (JRA) is the older term that was used ...

Crabbing system for an electron-ion collider

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

Castilla, Alejandro

2017-05-01

As high energy and nuclear physicists continue to push further the boundaries of knowledge using colliders, there is an imperative need, not only to increase the colliding beams' energies, but also to improve the accuracy of the experiments, and to collect a large quantity of events with good statistical sensitivity. To achieve the latter, it is necessary to collect more data by increasing the rate at which these processes are being produced and detected in the machine. This rate of events depends directly on the machine's luminosity. The luminosity itself is proportional to the frequency at which the beams aremore » being delivered, the number of particles in each beam, and inversely proportional to the cross-sectional size of the colliding beams. There are several approaches that can be considered to increase the events statistics in a collider other than increasing the luminosity, such as running the experiments for a longer time. However, this also elevates the operation expenses, while increasing the frequency at which the beams are delivered implies strong physical changes along the accelerator and the detectors. Therefore, it is preferred to increase the beam intensities and reduce the beams cross-sectional areas to achieve these higher luminosities. In the case where the goal is to push the limits, sometimes even beyond the machines design parameters, one must develop a detailed High Luminosity Scheme. Any high luminosity scheme on a modern collider considers|in one of their versions|the use of crab cavities to correct the geometrical reduction of the luminosity due to the beams crossing angle. In this dissertation, we present the design and testing of a proof-of-principle compact superconducting crab cavity, at 750 MHz, for the future electron-ion collider, currently under design at Jefferson Lab. In addition to the design and validation of the cavity prototype, we present the analysis of the first order beam dynamics and the integration of the crabbing

Crabbing System for an Electron-Ion Collider

NASA Astrophysics Data System (ADS)

Castilla, Alejandro

As high energy and nuclear physicists continue to push further the boundaries of knowledge using colliders, there is an imperative need, not only to increase the colliding beams' energies, but also to improve the accuracy of the experiments, and to collect a large quantity of events with good statistical sensitivity. To achieve the latter, it is necessary to collect more data by increasing the rate at which these pro- cesses are being produced and detected in the machine. This rate of events depends directly on the machine's luminosity. The luminosity itself is proportional to the frequency at which the beams are being delivered, the number of particles in each beam, and inversely proportional to the cross-sectional size of the colliding beams. There are several approaches that can be considered to increase the events statistics in a collider other than increasing the luminosity, such as running the experiments for a longer time. However, this also elevates the operation expenses, while increas- ing the frequency at which the beams are delivered implies strong physical changes along the accelerator and the detectors. Therefore, it is preferred to increase the beam intensities and reduce the beams cross-sectional areas to achieve these higher luminosities. In the case where the goal is to push the limits, sometimes even beyond the machines design parameters, one must develop a detailed High Luminosity Scheme. Any high luminosity scheme on a modern collider considers--in one of their versions--the use of crab cavities to correct the geometrical reduction of the luminosity due to the beams crossing angle. In this dissertation, we present the design and testing of a proof-of-principle compact superconducting crab cavity, at 750 MHz, for the future electron-ion collider, currently under design at Jefferson Lab. In addition to the design and validation of the cavity prototype, we present the analysis of the first order beam dynamics and the integration of the crabbing

Carbon and nitrogen balance of leaf-eating sesarmid crabs ( Neoepisesarma versicolor) offered different food sources

NASA Astrophysics Data System (ADS)

Thongtham, Nalinee; Kristensen, Erik

2005-10-01

Carbon and nitrogen budgets for the leaf-eating crab, Neoepisesarma versicolor, were established for individuals living on pure leaf diets. Crabs were fed fresh (green), senescent (yellow) and partly degraded (brown) leaves of the mangrove tree Rhizophora apiculata. Ingestion, egestion and metabolic loss of carbon and nitrogen were determined from laboratory experiments. In addition, bacterial abundance in various compartments of the crabs' digestive tract was enumerated after dissection of live individuals. Ingestion and egestion rates (in terms of dry weight) were highest, while the assimilation efficiency was poorest for crabs fed on brown leaves. The low assimilation efficiency was more than counteracted by the high ingestion rate providing more carbon for growth than for crabs fed green and yellow leaves. In any case, the results show that all types of leaves can provide adequate carbon while nitrogen was insufficient to support both maintenance (yellow leaves) and growth (green, yellow and brown leaves). Leaf-eating crabs must therefore obtain supplementary nitrogen by other means in order to meet their nitrogen requirement. Three hypotheses were evaluated: (1) crabs supplement their diet with bacteria and benthic microalgae by ingesting own faeces and/or selective grazing at the sediment surface; (2) assimilation of symbiotic nitrogen-fixing bacteria in the crabs' own intestinal system; and (3) nitrogen storage following occasional feeding on animal tissues (e.g. meiofauna and carcasses). It appears that hypothesis 1 is of limited importance for N. versicolor since faeces and sediment can only supply a minor fraction of the missing nitrogen due to physical constraints on the amount of material the crabs can consume. Hypothesis 2 can be ruled out because tests showed no nitrogen fixation activity in the intestinal system of N. versicolor. It is therefore likely that leaf-eating crabs provide most of their nitrogen requirement from intracellular deposits

Evidence of marine debris usage by the ghost crab Ocypode quadrata (Fabricius, 1787).

PubMed

Costa, Leonardo Lopes; Rangel, Danilo Freitas; Zalmon, Ilana Rosental

2018-03-01

Sandy beaches are sites of marine debris stranding, but the interaction of beach biota with waste is poorly studied. The objective of this study was to investigate whether the ghost crab Ocypode quadrata selects marine debris by types using a non-destructive method on sandy beaches of Southeastern Brazil. We found marine debris in 7% of 1696 surveyed burrows, and the ghost crabs selectivity was mainly by soft plastic (30%), straw (11%), rope (6%) and foam (4%). Burrows with marine debris showed higher occupation rate (~68%) compared to burrows without debris (~28%), indicating that these materials may increase the capacity of ghost crabs to memorize their burrows placement (homing). The percentage of marine debris was not always related to their amount in the drift line, but ghost crabs used more debris near urbanized areas. Future studies should test whether ghost crabs are using marine debris for feeding, homing or other mechanisms. Copyright © 2018 Elsevier Ltd. All rights reserved.

Neutrino Analysis of the 2010 September Crab Nebula Flare and Time-integrated Constraints on Neutrino Emission from the Crab Using IceCube

NASA Astrophysics Data System (ADS)

Abbasi, R.; Abdou, Y.; Abu-Zayyad, T.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Altmann, D.; Andeen, K.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S. W.; Bay, R.; Bazo Alba, J. L.; Beattie, K.; Beatty, J. J.; Bechet, S.; Becker, J. K.; Becker, K.-H.; Benabderrahmane, M. L.; BenZvi, S.; Berdermann, J.; Berghaus, P.; Berley, D.; Bernardini, E.; Bertrand, D.; Besson, D. Z.; Bindig, D.; Bissok, M.; Blaufuss, E.; Blumenthal, J.; Boersma, D. J.; Bohm, C.; Bose, D.; Böser, S.; Botner, O.; Brown, A. M.; Buitink, S.; Caballero-Mora, K. S.; Carson, M.; Chirkin, D.; Christy, B.; Clem, J.; Clevermann, F.; Cohen, S.; Colnard, C.; Cowen, D. F.; D'Agostino, M. V.; Danninger, M.; Daughhetee, J.; Davis, J. C.; De Clercq, C.; Demirörs, L.; Denger, T.; Depaepe, O.; Descamps, F.; Desiati, P.; de Vries-Uiterweerd, G.; DeYoung, T.; Díaz-Vélez, J. C.; Dierckxsens, M.; Dreyer, J.; Dumm, J. P.; Ehrlich, R.; Eisch, J.; Ellsworth, R. W.; Engdegård, O.; Euler, S.; Evenson, P. A.; Fadiran, O.; Fazely, A. R.; Fedynitch, A.; Feintzeig, J.; Feusels, T.; Filimonov, K.; Finley, C.; Fischer-Wasels, T.; Foerster, M. M.; Fox, B. D.; Franckowiak, A.; Franke, R.; Gaisser, T. K.; Gallagher, J.; Gerhardt, L.; Gladstone, L.; Glüsenkamp, T.; Goldschmidt, A.; Goodman, J. A.; Gora, D.; Grant, D.; Griesel, T.; Groß, A.; Grullon, S.; Gurtner, M.; Ha, C.; Hajismail, A.; Hallgren, A.; Halzen, F.; Han, K.; Hanson, K.; Heinen, D.; Helbing, K.; Herquet, P.; Hickford, S.; Hill, G. C.; Hoffman, K. D.; Homeier, A.; Hoshina, K.; Hubert, D.; Huelsnitz, W.; Hülß, J.-P.; Hulth, P. O.; Hultqvist, K.; Hussain, S.; Ishihara, A.; Jacobsen, J.; Japaridze, G. S.; Johansson, H.; Joseph, J. M.; Kampert, K.-H.; Kappes, A.; Karg, T.; Karle, A.; Kenny, P.; Kiryluk, J.; Kislat, F.; Klein, S. R.; Köhne, J.-H.; Kohnen, G.; Kolanoski, H.; Köpke, L.; Kopper, S.; Koskinen, D. J.; Kowalski, M.; Kowarik, T.; Krasberg, M.; Krings, T.; Kroll, G.; Kurahashi, N.; Kuwabara, T.; Labare, M.; Lafebre, S.; Laihem, K.; Landsman, H.; Larson, M. J.; Lauer, R.; Lünemann, J.; Madsen, J.; Majumdar, P.; Marotta, A.; Maruyama, R.; Mase, K.; Matis, H. S.; Meagher, K.; Merck, M.; Mészáros, P.; Meures, T.; Middell, E.; Milke, N.; Miller, J.; Montaruli, T.; Morse, R.; Movit, S. M.; Nahnhauer, R.; Nam, J. W.; Naumann, U.; Nießen, P.; Nygren, D. R.; Odrowski, S.; Olivas, A.; Olivo, M.; O'Murchadha, A.; Ono, M.; Panknin, S.; Paul, L.; Pérez de los Heros, C.; Petrovic, J.; Piegsa, A.; Pieloth, D.; Porrata, R.; Posselt, J.; Price, P. B.; Przybylski, G. T.; Rawlins, K.; Redl, P.; Resconi, E.; Rhode, W.; Ribordy, M.; Rizzo, A.; Rodrigues, J. P.; Roth, P.; Rothmaier, F.; Rott, C.; Ruhe, T.; Rutledge, D.; Ruzybayev, B.; Ryckbosch, D.; Sander, H.-G.; Santander, M.; Sarkar, S.; Schatto, K.; Schmidt, T.; Schönwald, A.; Schukraft, A.; Schultes, A.; Schulz, O.; Schunck, M.; Seckel, D.; Semburg, B.; Seo, S. H.; Sestayo, Y.; Seunarine, S.; Silvestri, A.; Slipak, A.; Spiczak, G. M.; Spiering, C.; Stamatikos, M.; Stanev, T.; Stephens, G.; Stezelberger, T.; Stokstad, R. G.; Stössl, A.; Stoyanov, S.; Strahler, E. A.; Straszheim, T.; Stür, M.; Sullivan, G. W.; Swillens, Q.; Taavola, H.; Taboada, I.; Tamburro, A.; Tepe, A.; Ter-Antonyan, S.; Tilav, S.; Toale, P. A.; Toscano, S.; Tosi, D.; Turčan, D.; van Eijndhoven, N.; Vandenbroucke, J.; Van Overloop, A.; van Santen, J.; Vehring, M.; Voge, M.; Walck, C.; Waldenmaier, T.; Wallraff, M.; Walter, M.; Weaver, Ch.; Wendt, C.; Westerhoff, S.; Whitehorn, N.; Wiebe, K.; Wiebusch, C. H.; Williams, D. R.; Wischnewski, R.; Wissing, H.; Wolf, M.; Wood, T. R.; Woschnagg, K.; Xu, C.; Xu, X. W.; Yodh, G.; Yoshida, S.; Zarzhitsky, P.; Zoll, M.

2012-01-01

We present the results of a search for high-energy muon neutrinos with the IceCube detector in coincidence with the Crab Nebula flare reported on 2010 September by various experiments. Due to the unusual flaring state of the otherwise steady source we performed a prompt analysis of the 79-string configuration data to search for neutrinos that might be emitted along with the observed γ-rays. We performed two different and complementary data selections of neutrino events in the time window of 10 days around the flare. One event selection is optimized for discovery of E -2 ν neutrino spectrum typical of first-order Fermi acceleration. A similar event selection has also been applied to the 40-string data to derive the time-integrated limits to the neutrino emission from the Crab. The other event selection was optimized for discovery of neutrino spectra with softer spectral index and TeV energy cutoffs as observed for various Galactic sources in γ-rays. The 90% confidence level (CL) best upper limits on the Crab flux during the 10 day flare are 4.73 × 10-11 cm-2 s-1 TeV-1 for an E -2 ν neutrino spectrum and 2.50 × 10-10 cm-2 s-1 TeV-1 for a softer neutrino spectra of E -2.7 ν, as indicated by Fermi measurements during the flare. In this paper, we also illustrate the impact of the time-integrated limit on the Crab neutrino steady emission. The limit obtained using 375.5 days of the 40-string configuration is compared to existing models of neutrino production from the Crab and its impact on astrophysical parameters is discussed. The most optimistic predictions of some models are already rejected by the IceCube neutrino telescope with more than 90% CL.

Oxygen and carbon dioxide sensitivity of ventilation in amphibious crabs, Cardisoma guanhumi, breathing air and water.

PubMed

Gannon, Andrew T; Henry, Raymond P

2004-05-01

Amphibious crabs, Cardisoma guanhumi, were acclimated to breathing either air or water and exposed to altered levels of oxygen and/or carbon dioxide in the medium. Hypercapnia (22, 36 and 73 torr CO(2)) stimulated a significant hypercapnic ventilatory response (HCVR) in both groups of crabs, with a much greater effect on scaphognathite frequency (Deltaf(SC)=+700%) in air-breathing crabs than water-breathing crabs (Deltaf(SC)=+100%). In contrast, hyperoxia induced significant hypoventilation in both sets of crabs. However, simultaneous hyperoxia and hypercapnia triggered a greater than 10-fold increase in f(SC) in air-breathing crabs but no change in water-breathing crabs. For water-breathing crabs hypoxia simultaneous with hypercapnia triggered the same response as hypoxia alone-bradycardia (-50%), and a significant increase in f(SC) at moderate exposures but not at the more extreme levels. The response of air-breathing crabs to hypoxia concurrent with hypercapnia was proportionally closer to the response to hypercapnia alone than to hypoxia. Thus, C. guanhumi were more sensitive to ambient CO(2) than O(2) when breathing air, characteristic of fully terrestrial species, and more sensitive to ambient O(2) when breathing water, characteristic of fully aquatic species. C. guanhumi possesses both an O(2)- and a CO(2)-based ventilatory drive whether breathing air or water, but the relative importance switches when the respiratory medium is altered.

40 CFR 408.40 - Applicability; description of the non-remote Alaskan crab meat processing subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

...-remote Alaskan crab meat processing subcategory. 408.40 Section 408.40 Protection of Environment... PROCESSING POINT SOURCE CATEGORY Non-Remote Alaskan Crab Meat Processing Subcategory § 408.40 Applicability; description of the non-remote Alaskan crab meat processing subcategory. The provisions of this subpart are...

40 CFR 408.40 - Applicability; description of the non-remote Alaskan crab meat processing subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

...-remote Alaskan crab meat processing subcategory. 408.40 Section 408.40 Protection of Environment... PROCESSING POINT SOURCE CATEGORY Non-Remote Alaskan Crab Meat Processing Subcategory § 408.40 Applicability; description of the non-remote Alaskan crab meat processing subcategory. The provisions of this subpart are...

DNA barcoding detected improper labelling and supersession of crab food served by restaurants in India.

PubMed

Vartak, Vivek Rohidas; Narasimmalu, Rajendran; Annam, Pavan Kumar; Singh, Dhirendra P; Lakra, Wazir S

2015-01-01

Detection of improper labelling of raw and processed seafood is of global importance for reducing commercial fraud and enhancing food safety. Crabs are crustaceans with intricate morphological as well as genetic divergence among species and are popular as seafood in restaurants. Owing to the high number of crab species available, it can be difficult to identify those included in particular food dishes, thus increasing the chance of supersession. DNA barcoding is an advanced technology for detecting improper food labelling and has been used successfully to authenticate seafood. This study identified 11 edible crab species from India by classical taxonomy and developed molecular barcodes with the cytochrome c oxidase I (COI) gene. These barcodes were used as reference barcodes for detecting any improper labelling of 50 restaurant crab samples. Neighbour-joining tree analysis with COI barcodes showed distinct clusters of restaurant samples with respective reference species. The study demonstrated 100% improper labelling of restaurant samples to cover up acts of inferior crab supersession. DNA barcoding successfully identified 11 edible crabs in accordance with classical taxonomy and discerned improper crab food labelling in restaurants of India. © 2014 Society of Chemical Industry.

Living on the edge: Distribution of Dungeness crab Cancer magister in a recently deglaciated fjord

USGS Publications Warehouse

Taggart, S. James; Hooge, P.N.; Mondragon, Jennifer; Hooge, Elizabeth Ross; Andrews, A.G.

2003-01-01

Glacier Bay, Alaska, has supported a productive Dungeness crab fishery, although the area where the fishery occurred was small relative to the remainder of the Bay. We hypothesized that 1 or more abiotic limiting factors prevented crabs from surviving in the upper Bay. We tested this hypothesis by systematically sampling for relative abundance of Dungeness crabs from the mouth to the head of the Bay. We measured salinity, temperature and turbidity at each of the sampling sites and at permanent stations to characterize the habitat within and among years. We expected to find a completely truncated spatial distribution. Instead, we found that adult Dungeness crabs can survive in habitats heavily influenced by tidewater glaciers. There were significantly fewer crabs in the upper Bay and a sharp decrease in abundance around 40 km from the mouth of the Bay. The region of the Bay beyond 40 km from the mouth had a very low density of predominately adult male crabs. The narrow size frequency distribution and the lack of small crabs is consistent with poor survival in one of the pre-adult life stages in the upper Bay.

Shell use and partitioning of two sympatric species of hermit crabs on a tropical mudflat

NASA Astrophysics Data System (ADS)

Teoh, Hong Wooi; Chong, Ving Ching

2014-02-01

Shell use and partitioning of two sympatric hermit crab species (Diogenes moosai and Diogenes lopochir), as determined by shell shape, size and availability, were examined from August 2009 to March 2011 in a tropical mudflat (Malaysia). Shells of 14 gastropod species were used but > 85% comprised shells of Cerithidea cingulata, Nassarius cf. olivaceus, Nassarius jacksonianus, and Thais malayensis. Shell partitioning between hermit crab species, sexes, and developmental stages was evident from occupied shells of different species, shapes, and sizes. Extreme bias in shell use pattern by male and female of both species of hermit crabs suggests that shell shape, which depends on shell species, is the major determinant of shell use. The hermit crab must however fit well into the shell so that compatibility between crab size and shell size becomes crucial. Although shell availability possibly influenced shell use and hermit crab distribution, this is not critical in a tropical setting of high gastropod diversity and abundance.

Responses of the crab Heterozius rotundifrons to heterospecific chemical alarm cues: phylogeny vs. ecological overlap.

PubMed

Hazlett, Brian A; McLay, Colin

2005-03-01

The big-handed brachyuran crab Heterozius rotundifrons extends the time spent in its anti-predator posture, limb extended posture, if exposed to chemical cues from crushed conspecifics. In this study, we tested whether crabs also respond to chemical cues from crushed heterospecific crabs, and if so, whether phylogenetic relations or ecological overlap is more important in influencing the duration of the anti-predator posture. Chemical cues from two other brachyuran crabs (Cyclograpsus lavauxi and Hemigrapsus sexdentatus), which do not overlap directly in ecological distribution with H. rotundifrons, elicited a duration of the anti-predator posture that was indistinguishable from that produced by conspecific chemical cues. In contrast, chemical cues from two anomuran crabs (Petrolisthes elongatus and Pagurus novizealandiae) that overlap in ecological distribution with H. rotundifrons, elicited durations of the antipredator posture that were significantly shorter than those of either conspecifics or more closely related crab species. Thus, phylogenetic relationship seems to be more important than ecological overlap in influencing anti-predator behavior in H. rotundifrons.

Electroless nickel – phosphorus coating on crab shell particles and its characterization

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

Arulvel, S., E-mail: gs.arulvel.research@gmail.com; Elayaperumal, A.; Jagatheeshwaran, M.S.

Being hydrophilic material, crab shell particles have only a limited number of applications. It is, therefore, necessary to modify the surface of the crab shell particles. To make them useful ever for the applications, the main theme we proposed in this article is to utilize crab shell particles (CSP) with the core coated with nickel phosphorus (NiP) as a shell using the electroless coating process. For dealing with serious environmental problems, utilization of waste bio-shells is always an important factor to be considered. Chelating ability of crab shell particles eliminates the surface activation in this work proceeding to the coatingmore » process. The functional group, phase structure, microstructure, chemical composition and thermal analysis of CSP and NiP/CSP were characterized using Fourier transform infra-red spectroscopy (FTIR), x-ray diffraction analyzer (XRD), scanning electron microscope (SEM), energy-dispersive x-ray spectroscopy (EDS), and thermogravimetric analysis (TGA). The combination of an amorphous and crystalline structure was exhibited by CSP and NiP/CSP. NiP/CSP has shown a better thermal stability when compared to uncoated CSP. Stability test, adsorption test, and conductivity test were conducted for the study of adsorption behavior and conductivity of the particles. CSP presented a hydrophilic property in contrast to hydrophobic NiP/CSP. NiP/CSP presented a conductivity of about 44% greater compared to the CSP without any fluctuations. - Highlights: • Utilization of crab shell waste is focused on. • NiP coating on crab shell particle is fabricated using electroless process. • Thermal analysis, stability test, adsorption test and conductivity test were done. • Organic matrix of crab shell particle favors the coating process. • Results demonstrate the characterization of CSP core – NiP shell structure.« less

Fiddler crabs facilitate Spartina alterniflora growth, mitigating periwinkle overgrazing of marsh habitat.

PubMed

Gittman, Rachel K; Keller, Danielle A

2013-12-01

Ecologists have long been interested in identifying and testing factors that drive top-down or bottom-up regulation of communities. Most studies have focused on factors that directly exert top-down (e.g., grazing) or bottom-up (e.g., nutrient availability) control on primary production. For example, recent studies in salt marshes have demonstrated that fronts of Littoraria irrorata periwinkles can overgraze Spartina alterniflora and convert marsh to mudflat. The importance of indirect, bottom-up effects, particularly facilitation, in enhancing primary production has also recently been explored. Previous field studies separately revealed that fiddler crabs, which burrow to depths of more than 30 cm, can oxygenate marsh sediments and redistribute nutrients, thereby relieving the stress of anoxia and enhancing S. alterniflora growth. However, to our knowledge, no studies to date have explored how nontrophic facilitators can mediate top-down effects (i.e., grazing) on primary-producer biomass. We conducted a field study testing whether fiddler crabs can facilitate S. alterniflora growth sufficiently to mitigate overgrazing by periwinkles and thus sustain S. alterniflora marsh. As inferred from contrasts to experimental plots lacking periwinkles and fiddler crabs, periwinkles alone exerted top-down control of total aboveground biomass and net growth of S. alterniflora. When fiddler crabs were included, they counteracted the effects of periwinkles on net S. alterniflora growth. Sediment oxygen levels were greater and S. alterniflora belowground biomass was lower where fiddler crabs were present, implying that fiddler crab burrowing enhanced S. alterniflora growth. Consequently, in the stressful interior S. alterniflora marsh, where subsurface soil anoxia is widespread, fiddler crab facilitation can mitigate top-down control by periwinkles and can limit and possibly prevent loss of biogenically structured marsh habitat and its ecosystem services.

Lead burdens and behavioral impairments of the lined shore crab Pachygrapsus crassipes

USGS Publications Warehouse

Hui, C.A.

2002-01-01

Sublethal burdens of lead impair behaviors critical to survival in a variety of animals. In a test arena, I measured refuge-seeking behaviors of adult, male, lined shore crabs from lead-free and lead-contaminated sites. The body sizes of the test groups did not differ although the mean total body lead burdens differed by over 2,300%. A lead-contaminated environment does not appear to affect growth. Each of the 31 crabs had at least six trials in the arena. The fraction of trials with more than one pause, number of pauses per trial, mean time per pause, and the fraction of time a crab spent in pauses did not differ between groups. The absence of behavioral effects of the lead burdens may be because a large portion of the lead burden was sequestered in the carapace. The neurological and other soft tissues would then have lower levels of lead. Predators that ingest primarily soft tissues would have little exposure to the lead burden of these crabs. Those that also ingest the carapace may benefit from its high calcium content that inhibits lead uptake from the gut, regardless of the location of lead in the crab body.

Analysis of repeated signals during shell fights in the hermit crab Pagurus bernhardus

PubMed Central

Briffa, M.; Elwood, R. W.; Dick, J. T. A.

1998-01-01

Shell exchanges between hermit crabs may occur after a period of shell rapping, when the initiating or attacking crab brings its shell rapidly and repeatedly into contact with the shell of the non-initiator or defender, in a series of bouts. There are two opposing models of hermit crab shell exchange and the function of shell rapping. The negotiation model views shell exchange as a mutualistic activity, in which the initiator supplies information about the quality of its shell via the fundamental frequency of the rapping sound. The aggression model views shell rapping as either detrimental to the defending crab, or as providing it with information about the initiator's ability or motivation to continue, or both. The negotiation model makes no predictions about the temporal pattern of rapping, but under the aggression model it would be expected that crabs that rapped more vigorously would be more likely to effect an exchange. Repeating the signal could be expected under either model. Crabs that achieve an exchange rap more vigorously, rapping is more persistent when a clear gain in shell quality may be achieved, and the vigour is greater when the relative resource-holding potential (or 'fighting ability') is high. These findings support the aggression model rather than the negotiation model. Contrary to the predictions of game theory, crabs that do not effect an exchange appear to signal that they are about to give up. The data suggest that rapping is performed repeatedly because the accumulation of all of the performances acts as a signal of stamina.

Hypolobocera guayaquilensis (Decapoda: Pseudothelphusidae): A New Crab Intermediate Host of Paragonimus mexicanus in Manabí Province, Ecuador

PubMed Central

Calvopina, Manuel; Romero-Alvarez, Daniel; Rendon, Melina; Takagi, Hidekazu; Sugiyama, Hiromu

2018-01-01

To determine that Paragonimus sp. is actively transmitted in a tropical area of the Pacific region of Ecuador where human cases of pulmonary paragonimiasis have recently been documented, a total of 75 freshwater crabs were collected from 2 different streams in the Pedernales area of Manabí Province, Ecuador. All collected crabs were identified as Hypolobocera guayaquilensis based on morphological characteristics of the male gonopods. The hepatopancreas of each crab was examined by compressing it between 2 glass plates followed by observation under a stereomicroscope. Excysted Paragonimus metacercariae were detected in 39 (52.0%) crabs and their densities varied from 1 to 32 per infected crab. There was a positive relationship between crab size and metacercarial density. Sequences of the second internal transcribed spacer region of the ribosomal RNA gene of the Paragonimus metacercariae obtained in this study were identical to those of Paragonimus mexicanus deposited in the DDBJ/EMBL/GenBank database. Thus, the present study is the first to confirm that the crab species H. guayaquilensis is the second intermediate host of P. mexicanus in Manabí Province, Ecuador. Because this crab might be the possible source of human infections in this area, residents should pay attention to improper crab-eating habits related with a neglected parasitic disease, i.e., paragonimiasis. PMID:29742874

Fecampia erythrocephala rediscovered: prevalence and distribution of a parasitoid of the European shore crab, Carcinus maenas

USGS Publications Warehouse

Kuris, Armand M.; Torchin, Mark E.; Lafferty, Kevin D.

2002-01-01

An ecological assessment of Fecampia erythrocephala, reporting its habitat distribution, abundance, host specificity, size-specific prevalence, frequency distribution among hosts, effect on host growth, and its site specificity within these hosts is presented. At the Isle of Man and near Plymouth, Fecampia erythrocephala cocoons were generally abundant on the undersides of rocks in the Ascophyllum and Fucus serratus zones. Infected crabs were also most common in these habitats. Both Carcinus maenas and Cancer pagurus were parasitized at similar prevalences, although the former species was relatively much more common in the habitats where the worm cocoons were abundant. Fecampia erythrocephala did not infect crabs larger than 11 mm carapace width, and prevalence decreased significantly with crab size. Prevalences reached 11% in areas where cocoons were abundant. Together with the large size of these worms relative to the size of the host crabs and the observations on worm emergence, these life history features indicate that F. erythrocephala is a parasitoid of young shore crabs. Fecampia erythrocephala cocoon abundance is often high in localized areas and size-prevalence information suggests that worms mature rapidly in these crabs. This suggests that F. erythrocephala is an important contributor to crab mortality and to the ecology of shore crabs at these sites.

Range-wide wetland associations of the King Rail: A multi-scale approach

USGS Publications Warehouse

Glisson, Wesley J.; Conway, Courtney J.; Nadeau, Christopher P.; Borgmann, Kathi L.; Laxson, Thomas A.

2015-01-01

King Rail populations have declined and identifying wetland features that influence King Rail occupancy can help prevent further population declines. We integrated continent-wide marsh bird survey data with spatial wetland data from the National Wetland Inventory (NWI) to examine wetland features that influenced King Rail occupancy throughout the species’ range. We analyzed wetland data at 7 spatial scales to examine the scale(s) at which 68 wetland features were most strongly related to King Rail occupancy. Occupancy was most strongly associated with estuarine features and brackish and tidal saltwater regimes. King Rail occupancy was positively associated with emergent and scrub-shrub wetlands and negatively associated with forested wetlands. The best spatial scale for assessing King Rail occupancy differed among wetland features; we could not identify one spatial scale (among all wetland features) that best explained variation in occupancy. Future research on King Rail habitat that includes multiple spatial scales is more likely to identify the suite of features that influence occupancy. Our results indicate that NWI data may be useful for predicting occupancy based on broad habitat features across the King Rail’s range, which may help inform management decisions for this and other wetland-dependent birds.

76 FR 25545 - Safety Zone; Blue Crab Festival Fireworks Display, Little River, Little River, SC

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-05

...-AA00 Safety Zone; Blue Crab Festival Fireworks Display, Little River, Little River, SC AGENCY: Coast... zone on the waters of Little River in Little River, South Carolina during the Blue Crab Festival... this rule because the Coast Guard did not receive notice of the Blue Crab Festival Fireworks Display...

Giant robber crabs monitored from space: GPS-based telemetric studies on Christmas Island (Indian Ocean).

PubMed

Krieger, Jakob; Grandy, Ronald; Drew, Michelle M; Erland, Susanne; Stensmyr, Marcus C; Harzsch, Steffen; Hansson, Bill S

2012-01-01

We investigated the navigational capabilities of the world's largest land-living arthropod, the giant robber crab Birgus latro (Anomura, Coenobitidae); this crab reaches 4 kg in weight and can reach an age of up to 60 years. Populations are distributed over small Indo-Pacific islands of the tropics, including Christmas Island (Indian Ocean). Although this species has served as a crustacean model to explore anatomical, physiological, and ecological aspects of terrestrial adaptations, few behavioral analyses of it exist. We used a GPS-based telemetric system to analyze movements of freely roaming robber crabs, the first large-scale study of any arthropod using GPS technology to monitor behavior. Although female robber crabs are known to migrate to the coast for breeding, no such observations have been recorded for male animals. In total, we equipped 55 male robber crabs with GPS tags, successfully recording more than 1,500 crab days of activity, and followed some individual animals for as long as three months. Besides site fidelity with short-distance excursions, our data reveal long-distance movements (several kilometers) between the coast and the inland rainforest. These movements are likely related to mating, saltwater drinking and foraging. The tracking patterns indicate that crabs form route memories. Furthermore, translocation experiments show that robber crabs are capable of homing over large distances. We discuss if the search behavior induced in these experiments suggests path integration as another important navigation strategy.

Giant Robber Crabs Monitored from Space: GPS-Based Telemetric Studies on Christmas Island (Indian Ocean)

PubMed Central

Krieger, Jakob; Grandy, Ronald; Drew, Michelle M.; Erland, Susanne; Stensmyr, Marcus C.; Harzsch, Steffen; Hansson, Bill S.

2012-01-01

We investigated the navigational capabilities of the world's largest land-living arthropod, the giant robber crab Birgus latro (Anomura, Coenobitidae); this crab reaches 4 kg in weight and can reach an age of up to 60 years. Populations are distributed over small Indo-Pacific islands of the tropics, including Christmas Island (Indian Ocean). Although this species has served as a crustacean model to explore anatomical, physiological, and ecological aspects of terrestrial adaptations, few behavioral analyses of it exist. We used a GPS-based telemetric system to analyze movements of freely roaming robber crabs, the first large-scale study of any arthropod using GPS technology to monitor behavior. Although female robber crabs are known to migrate to the coast for breeding, no such observations have been recorded for male animals. In total, we equipped 55 male robber crabs with GPS tags, successfully recording more than 1,500 crab days of activity, and followed some individual animals for as long as three months. Besides site fidelity with short-distance excursions, our data reveal long-distance movements (several kilometers) between the coast and the inland rainforest. These movements are likely related to mating, saltwater drinking and foraging. The tracking patterns indicate that crabs form route memories. Furthermore, translocation experiments show that robber crabs are capable of homing over large distances. We discuss if the search behavior induced in these experiments suggests path integration as another important navigation strategy. PMID:23166774

A potential vector of domoic acid: the swimming crab Polybius henslowii Leach (Decapoda-brachyura).

PubMed

Costa, Pedro R; Rodrigues, Susana M; Botelho, Maria J; Sampayo, Maria Antónia de M

2003-08-01

The swimming crab Polybius henslowii may play an important role in the movement of the amnesic shellfish toxin, domoic acid (DA), through the marine food chain. High DA concentrations have been determined in crab samples harvested along the Portuguese coast during the summer of 2002, reaching a level of 323.1 microg DA/g crab tissue. Toxin distribution in the different crab organs showed levels as high as 571.6 microg DA/g in the visceral tissues. Levels of toxin 4-12 times lower were detected in the remaining tissues. This crab might be a prominent vector of the toxin to higher trophic levels, including fishes, sea birds and even humans. In Portugal P. henslowii is commercialised during the summer in some local markets. DA concentrations were found close to the legal limit of 20 microg/g in samples purchased at Figueira da Foz market. The crabs are boiled prior to reaching the consumers. The cooking process was evaluated. Determination of toxin losses during the cooking process showed a toxin reduction higher than 50%. DA was determined by HPLC-UV and confirmed by spectra acquired with diode-array detector.

50 CFR 100.28 - Subsistence taking of shellfish.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Makhnati Island as described in § __.3(b)(5) of these regulations. (2) Prince William Sound Area. No marine...) In the subsistence taking of king crab: (A) The annual limit is three crabs per household; only male... boundaries of Womens Bay, Gibson Cove, and an area defined by a line 1/2 mile on either side of the mouth of...

50 CFR 100.28 - Subsistence taking of shellfish.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Makhnati Island as described in § __.3(b)(5) of these regulations. (2) Prince William Sound Area. No marine...) In the subsistence taking of king crab: (A) The annual limit is three crabs per household; only male... boundaries of Womens Bay, Gibson Cove, and an area defined by a line 1/2 mile on either side of the mouth of...

50 CFR 100.28 - Subsistence taking of shellfish.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Makhnati Island as described in § __.3(b)(5) of these regulations. (2) Prince William Sound Area. No marine...) In the subsistence taking of king crab: (A) The annual limit is three crabs per household; only male... boundaries of Womens Bay, Gibson Cove, and an area defined by a line 1/2 mile on either side of the mouth of...

50 CFR 100.28 - Subsistence taking of shellfish.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Makhnati Island as described in § __.3(b)(5) of these regulations. (2) Prince William Sound Area. No marine...) In the subsistence taking of king crab: (A) The annual limit is three crabs per household; only male... boundaries of Womens Bay, Gibson Cove, and an area defined by a line 1/2 mile on either side of the mouth of...

[A study of treatise on medicine by King Sejo].

PubMed

Hwang, Im-kyung; Hwang, Sang-lk

2003-12-01

This paper explores historical backgrounds and contents of Treatise on Medicine written by King Sejo (r. 1455-1468) including his views on traditional medicine and pharmacy in the early Chosen period. The Treatise declared by King Sejo in 1463 has been considered as an important and unique manual of medicine because it was the exclusive example written by the king of Chosen. It was the King Sejo' s era when the medical milieu in both social and medical aspects was highly encouraged thanks to the previous achievements by King Sejong the Great (r.1418-1450). King Sejo, in particular, who was much interested in practical learning called 'Miscellaneous Studies', emphasized on court medicine. His writing can be understood in such historical frame. Another reason why he wrote the Treatise can be said that he felt necessary for establishing the medical ethic codes for inefficient court medicine-officials. In personal background, he tried to find available remedies since he had been suffered from some chronic diseases. The contents of the Treatise can be broadly fallen to the clinical and ethical aspects. In the former one, the Treatise focuses on treatment without hesitation through the sharp and exact diagnosis by medical doctors. In the latter one, eight categories of medical doctors are discussed according to their moral degrees: sim'eui, sik'eui, yak'eui, hon'eui, kwang eui, mang'eui, sa'eui, and sal'eui. Finally, musim' ji-eui was supplemented. Among them, sal'eui, medicine-official lacking both medical ability and ethical attitude, was classified as the lowest degree; sim'eui, medicine-official sincerely making his all efforts for patients, was thought to be a paragon of medical morality. In conclusion, the Treatise on Medicine by King Sejo played an important role as a manual for the principle of medical practice and for the instruction to enhance ethical attitude among medicine-officials.

Robotic crabs reveal that female fiddler crabs are sensitive to changes in male display rate.

PubMed

Mowles, Sophie L; Jennions, Michael D; Backwell, Patricia R Y

2018-01-01

Males often produce dynamic, repetitive courtship displays that can be demanding to perform and might advertise male quality to females. A key feature of demanding displays is that they can change in intensity: escalating as a male increases his signalling effort, but de-escalating as a signaller becomes fatigued. Here, we investigated whether female fiddler crabs, Uca mjoebergi , are sensitive to changes in male courtship wave rate. We performed playback experiments using robotic male crabs that had the same mean wave rate, but either escalated, de-escalated or remained constant. Females demonstrated a strong preference for escalating robots, but showed mixed responses to robots that de-escalated ('fast' to 'slow') compared to those that waved at a constant 'medium' rate. These findings demonstrate that females can discern changes in male display rate, and prefer males that escalate, but that females are also sensitive to past display rates indicative of prior vigour. © 2018 The Authors.

Intraguild predation by shore crabs affects mortality, behavior, growth, and densities of California horn snails

USGS Publications Warehouse

Lorda, J.; Hechinger, R.F.; Cooper, S. D.; Kuris, A. M.; Lafferty, Kevin D.

2016-01-01

The California horn snail, Cerithideopsis californica, and the shore crabs, Pachygrapsus crassipesand Hemigrapsus oregonensis, compete for epibenthic microalgae, but the crabs also eat snails. Such intraguild predation is common in nature, despite models predicting instability. Using a series of manipulations and field surveys, we examined intraguild predation from several angles, including the effects of stage-dependent predation along with direct consumptive and nonconsumptive predator effects on intraguild prey. In the laboratory, we found that crabs fed on macroalgae, snail eggs, and snails, and the size of consumed snails increased with predator crab size. In field experiments, snails grew less in the presence of crabs partially because snails behaved differently and were buried in the sediment (nonconsumptive effects). Consistent with these results, crab and snail abundances were negatively correlated in three field surveys conducted at three different spatial scales in estuaries of California, Baja California, and Baja California Sur: (1) among 61 sites spanning multiple habitat types in three estuaries, (2) among the habitats of 13 estuaries, and (3) among 34 tidal creek sites in one estuary. These results indicate that shore crabs are intraguild predators on California horn snails that affect snail populations via predation and by influencing snail behavior and performance.

Biomaterial compounds and bioactivity of horseshoe crab Carsinoscorpius rotundicauda biomass harvested from the Madura Strait

NASA Astrophysics Data System (ADS)

Asih, Eka Nurrahema Ning; Kawaroe, Mujizat; Bengen, Dietriech G.

2018-03-01

Carsinoscorpius rotundicauda or horseshoe crab biomass has great potential in pharmaceutical aspects, one of them as an antibacterial substance. Information related to the benefits of Carsinoscorpius rotundicauda biomass such as meat and blood is essential because in fact, this species is considered a pest by fishermen, a low market value and has no legal protection in Indonesia. The purpose of this study was to determine the content of biomaterial compounds of meat and bioactivity of Carsinoscorpius rotundicauda plasma on bacterial inhibition from three different stations harvested from the waters in Madura Strait. The observation of the utilization of the potential from horseshoe crab biomass ie meat and plasma was performed by measuring the content of biomaterial compound in horseshoe crab meat by HPLC method and zone of inhibition test for gram-positive and gram-negative bacteria in horseshoe crab plasma. Analysis of the relationship between the two parameters used the Principal Component Analysis. The highest content of biomaterial compounds of monoterpenoid and zoosterol is found in horseshoe crab from Bangkalan waters, namely monoterpenoid (18.33 ppm) and zoosterol (22.67 ppm), while the smallest compound content obtained in horseshoe crab from Probolinggo waters, namely monoterpenoid (13.67) ppm and zoosterol (17.33 ppm). The bioactivity of Dark Blue Plasma (BDP) and Light Blue Plasma (LBP) samples of horseshoe crab obtained around the Madura Strait has the ability to inhibit gram-positive bacteria higher than gram-negative bacteria. The total average of DBP plasma inhibitory power on Staphylococcus aureus was 10.00 mm and 10.07 mm on Bacillus, while that in LBP sample, Staphylococcus aureus was 9.11 mm and Bacillus was 9.67 mm. The high biomaterial compound content of horseshoe crab is in line with the ability of horseshoe crab plasma to inhibit Bacillus and Staphylococcus aureus.

Physical characteristics of dungeness crab and halibut habitats in Glacier Bay

USGS Publications Warehouse

Cochrane, Guy R.; Carlson, Paul R.; Denny, Jane F.; Boyle, Michael E.; Taggart, S. James; Hooge, Philip N.

1998-01-01

In Glacier Bay National Park, Alaska there are ongoing studies of Dungeness Crab (Cancer magister) and Pacific Halibut (Hippoglosus stenolepis). Scientists of the United States Geological Survey (USGS) are attempting to ascertain life history, distribution, and abundance, and to determine the effects of commercial fishing in the park (Carlson et al., 1998). Statistical sampling studies suggest that seafloor characteristics and bathymetry affect the distribution, abundance and behavior of benthic species. Examples include the distribution of Dungeness crab which varies from 78 to 2012 crabs/ha in nearshore areas to depths of 18 m (O'Clair et al., 1995), and changes in halibut foraging behavior according to bottom type (Chilton et al., 1995). This report discusses geophysical data collected in six areas within the park in 1998. The geophysical surveying done in this and previous studies will be combined with existing population and sonic-tracking data sets as well as future sediment sampling, scuba, submersible, and bottom video camera observations to better understand Dungeness crab and Pacific halibut habitat relationships.

Ultraviolet Imaging Telescope observations of the Crab Nebula

NASA Technical Reports Server (NTRS)

Hennessy, Gregory S.; O'Connell, Robert W.; Cheng, Kwang P.; Bohlin, Ralph C.; Collins, Nicholas R.; Gull, Theodore P.; Hintzen, Paul; Isensee, Joan E.; Landsman, Wayne B.; Roberts, Morton S.

1992-01-01

We obtained ultraviolet images of the Crab Nebula with the Ultraviolet Imaging Telescope during the Astro-1 Space Shuttle mission in 1990 December. The UV continuum morphology of the Crab is generally similar to that in the optical region, but the wispy structures are less conspicuous in the UV and X-ray. UV line emission from the thermal filaments is not strong. UV spectral index maps with a resolution of 10 arcsecs show a significant gradient across the nebula, with the outer parts being redder, as expected from synchrotron losses. The location of the bluest synchrotron continuum does not coincide with the pulsar.

Did the Crab Pulsar Undergo a Small Glitch in 2006 Late March/Early April?

NASA Astrophysics Data System (ADS)

Vivekanand, M.

2016-08-01

On 2006 August 23 the Crab Pulsar underwent a glitch, which was reported by the Jodrell Bank and the Xinjiang radio observatories. Neither data are available to the public. However, the Jodrell group publishes monthly arrival times of the Crab Pulsar pulse (their actual observations are done daily), and using these, it is shown that about 5 months earlier the Crab Pulsar probably underwent a small glitch, which has not been reported before. Neither observatory discusses the detailed analysis of data from 2006 March to August; either they may not have detected this small glitch, or they may have attributed it to timing noise in the Crab Pulsar. The above result is verified using X-ray data from RXTE. If this is indeed true, this is probably the smallest glitch observed in the Crab Pulsar so far, whose implications are discussed. This work addresses the confusion possible between small-magnitude glitches and timing noise in pulsars.

DID THE CRAB PULSAR UNDERGO A SMALL GLITCH IN 2006 LATE MARCH/EARLY APRIL?

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

Vivekanand, M., E-mail: viv.maddali@gmail.com

2016-08-01

On 2006 August 23 the Crab Pulsar underwent a glitch, which was reported by the Jodrell Bank and the Xinjiang radio observatories. Neither data are available to the public. However, the Jodrell group publishes monthly arrival times of the Crab Pulsar pulse (their actual observations are done daily), and using these, it is shown that about 5 months earlier the Crab Pulsar probably underwent a small glitch, which has not been reported before. Neither observatory discusses the detailed analysis of data from 2006 March to August; either they may not have detected this small glitch, or they may have attributedmore » it to timing noise in the Crab Pulsar. The above result is verified using X-ray data from RXTE . If this is indeed true, this is probably the smallest glitch observed in the Crab Pulsar so far, whose implications are discussed. This work addresses the confusion possible between small-magnitude glitches and timing noise in pulsars.« less

When a Standard Candle Flickers: Crab Nebula Variations in Hard X-rays

NASA Technical Reports Server (NTRS)

Wilson-Hodge, Collen A.; Cherry, M. L.; Case, G. L.; Baumgartner, W. H.; Beklen, E.; Bhat, P. N.; Briggs, M. S.; Camero-Arranz, A.; Chaplin, V.; Connaughton, V.;

The bioeconomic impact of different management regulations on the Chesapeake Bay blue crab fishery

USGS Publications Warehouse

Bunnell, David B.; Lipton, Douglas W.; Miller, Thomas J.

2010-01-01

The harvest of blue crabs Callinectes sapidus in Chesapeake Bay declined 46% between 1993 and 2001 and remained low through 2008. Because the total market value of this fishery has declined by an average of US $ 3.3 million per year since 1993, the commercial fishery has been challenged to maintain profitability. We developed a bioeconomic simulation model of the Chesapeake Bay blue crab fishery to aid managers in determining which regulations will maximize revenues while ensuring a sustainable harvest. We compared 15 different management scenarios, including those implemented by Maryland and Virginia between 2007 and 2009, that sought to reduce female crab harvest and nine others that used seasonal closures, different size regulations, or the elimination of fishing for specific market categories. Six scenarios produced the highest revenues: the 2008 and 2009 Maryland regulations, spring and fall closures for female blue crabs, and 152- and 165-mm maximum size limits for females. Our most important finding was that for each state the 2008 and 2009 scenarios that implemented early closures of the female crab fishery produced higher revenues than the 2007 scenario, in which no early female closures were implemented. We conclude that the use of maximum size limits for female crabs would not be feasible despite their potentially high revenue, given the likelihood that the soft-shell and peeler fisheries cannot be expanded beyond their current capacity and the potentially high mortality rate for culled individuals that are the incorrect size. Our model results support the current use of seasonal closures for females, which permit relatively high exploitation of males and soft-shell and peeler blue crabs (which have high prices) while keeping the female crab harvest sustainable. Further, our bioeconomic model allows for the inclusion of an economic viewpoint along with biological data when target reference points are set by managers.

Overview of environmental and hydrogeologic conditions at King Salmon, Alaska

USGS Publications Warehouse

Waythomas, C.F.

1994-01-01

The Federal Aviation Administration is conducting preliminary environmental assessments at most of its present or former facilities in Alaska. Information about environmental conditions at King Salmon, Alaska are presented in this report. This report gives an overview of the geology, hydro- logy, and climate of the King Salmon area and describes general geohydrologic conditions. A thick alluvial aquifer underlies King Salmon and both ground water and surface water are plentiful in the area.

Neutrino Analysis of the September 2010 Crab Nebula Flare and Time-Integrated Constraints on Neutrino Emission from the Crab Using IceCube

NASA Technical Reports Server (NTRS)

Abbasi, R.; Abdou, Y.; Abu-Zayyad, T.; Adams, J.; Aguilar, A.; Ahlers, M.; Altmann; Andeen, K.; Auffenberg, J; Bai, X.;

Neutrino Analysis of the September 2010 Crab Nebula Flare and Time-integrated Constraints on Neutrino Emission From the Crab Using IceCube

NASA Technical Reports Server (NTRS)

Stamatikos, M.; Abbasi, R.; Abdou, Y.; Abu-Zayyad, T.; Adams, J.; Aguliar, J. A.; Ahlers, M.; Altmann, D.; Andeen, K.; Auffenberg, J.;

Physical characteristics of dungeness crab and halibut habitats in Whidbey Passage, Alaska

USGS Publications Warehouse

Cochrane, Guy R.; Carlson, Paul R.; Boyle, Michael E.; Gabel, Gregory L.; Hooge, Philip N.

2000-01-01

In Glacier Bay National Park, Alaska there are ongoing studies of Dungeness Crab (Cancer magister) and Pacific Halibut (Hippoglosus stenolepis). Scientists of the United States Geological Survey (USGS) are attempting to ascertain life history, distribution, and abundance, and to determine the effects of commercial fishing in the park (Carlson et al., 1998). Statistical sampling studies suggest that seafloor characteristics and bathymetry affect the distribution, abundance and behavior of benthic species. Examples include the distribution of Dungeness crab which varies from 78 to 2012 crabs/ha in nearshore areas to depths of 18 m (O'Clair et al., 1995), and changes in halibut foraging behavior according to bottom type (Chilton et al., 1995). This report discusses geophysical data collected within the park in 1998. The geophysical surveying done in this and previous studies will be combined with existing population and sonic-tracking data sets as well as future sediment sampling, scuba, submersible, and bottom video camera observations to better understand Dungeness crab and Pacific halibut habitat relationships.

Widespread and evolutionary analysis of a MITE family Monkey King in Brassicaceae.

PubMed

Dai, Shutao; Hou, Jinna; Long, Yan; Wang, Jing; Li, Cong; Xiao, Qinqin; Jiang, Xiaoxue; Zou, Xiaoxiao; Zou, Jun; Meng, Jinling

2015-06-19

Miniature inverted repeat transposable elements (MITEs) are important components of eukaryotic genomes, with hundreds of families and many copies, which may play important roles in gene regulation and genome evolution. However, few studies have investigated the molecular mechanisms involved. In our previous study, a Tourist-like MITE, Monkey King, was identified from the promoter region of a flowering time gene, BnFLC.A10, in Brassica napus. Based on this MITE, the characteristics and potential roles on gene regulation of the MITE family were analyzed in Brassicaceae. The characteristics of the Tourist-like MITE family Monkey King in Brassicaceae, including its distribution, copies and insertion sites in the genomes of major Brassicaceae species were analyzed in this study. Monkey King was actively amplified in Brassica after divergence from Arabidopsis, which was indicated by the prompt increase in copy number and by phylogenetic analysis. The genomic variations caused by Monkey King insertions, both intra- and inter-species in Brassica, were traced by PCR amplification. Genomic sequence analysis showed that most complete Monkey King elements are located in gene-rich regions, less than 3kb from genes, in both the B. rapa and A. thaliana genomes. Sixty-seven Brassica expressed sequence tags carrying Monkey King fragments were also identified from the NCBI database. Bisulfite sequencing identified specific DNA methylation of cytosine residues in the Monkey King sequence. A fragment containing putative TATA-box motifs in the MITE sequence could bind with nuclear protein(s) extracted from leaves of B. napus plants. A Monkey King-related microRNA, bna-miR6031, was identified in the microRNA database. In transgenic A. thaliana, when the Monkey King element was inserted upstream of 35S promoter, the promoter activity was weakened. Monkey King, a Brassicaceae Tourist-like MITE family, has amplified relatively recently and has induced intra- and inter-species genomic

Juvenile Arrests, 2000. Juvenile Justice Bulletin.

ERIC Educational Resources Information Center

Snyder, Howard N.

This bulletin examines the national and state juvenile arrest rate in 2000 using data reported annually by local law enforcement agencies nationwide to the FBI's Uniform Crime Reporting program. Results indicate that the murder rate in 2000 was the lowest since 1965; juvenile arrests for violence in 2000 were the lowest since 1988; few juveniles…

27. VIEW OF THE OFFICE CREATED FOR MARTIN LUTHER KING ...

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

27. VIEW OF THE OFFICE CREATED FOR MARTIN LUTHER KING JR, LOOKING TOWARDS MAIN DOOR INTO SECRETARY'S OFFICE. - Dexter Avenue King Memorial Baptist Church, 454 Dexter Avenue, Montgomery, Montgomery County, AL

Juvenile Justice in Milwaukee

ERIC Educational Resources Information Center

Williams, Gary L.; Greer, Lanetta

2010-01-01

Historically, there have been several attempts made to address issues surrounding juvenile delinquency. The Wisconsin Legislature outlines the objectives of the juvenile justice system in the Juvenile Justice Code in s. 939.01, ?to promote a juvenile justice system capable of dealing with the problem of juvenile delinquency, a system which will…

Climate Change Effects on Respiration Rates of Blue Crab (Callinectes sapidus) from the Patuxent River, Chesapeake Bay

NASA Astrophysics Data System (ADS)

Nyffeler, A.

2016-02-01

A rise in atmospheric CO2 induces a greenhouse effect that also causes ocean temperatures and CO2 levels to rise. These environmental changes may represent an additional energetic cost for blue crabs because they rely on the concentration of CO2 in the water to deposit calcium carbonate in their shells. We conducted a respiration experiment to measure the effect of climate change on crab metabolism. Crabs were collected from the Chesapeake Bay and exposed to different heated and acidified conditions. After crabs had been exposed to the environmental conditions in the chambers for two molts, they were placed in respiration chambers to measure rates of oxygen consumption. Results indicated different trends in respiration rates between the treatments, although the patterns were not statistically significant. Crabs exposed to higher temperatures showed elevated respiration rates, while crabs exposed to high CO2 demonstrated decreased respiration rates. The two factors of climate change (high temperature and high CO2) did not demonstrate the highest respiration rate, but rather the crabs exposed to high temperatures and ambient CO2 showed the highest mean respiration rate. These data suggest that crab metabolism may not change as much as expected due to climate changes.

Impacts of Habitat Complexity on Physiology: Purple Shore Crabs Tolerate Osmotic Stress for Shelter

NASA Astrophysics Data System (ADS)

McGaw, I. J.

2001-12-01

Purple shore crabs, Hemigrapsus nudus (Crustacea: Decapoda), can survive indefinitely in salinities of 8 (25% SW), but also tolerate short-term exposure to salinities as low as 2. In the laboratory their salinity preference range, determined from choice chamber experiments, is 22-32 and they can discriminate between pairs of salinities separated by a difference of 2. These crabs show a strong positive thigmotaxis and a weak negative phototaxis and tend to choose environments with available shelter. The presence of shelter significantly alters the behaviour of this species. When shelter is available the salinity preference range is 10-32. Even in salinities below this preference range, the presence of shelter prolongs the time spent in the lower test salinities. This change in behaviour has implications on the crab's physiology: the haemolymph osmolality falls to lower levels when crabs remain in low salinity under shelters. In the field, H. nudus is found in creeks with salinities close to freshwater and they may remain in this salinity for up to 11 h, if there are rocks under which to shelter. An increase in habitat complexity increases the number of crabs that are found within the creek. These crabs in the low salinity environment have a lower haemolymph osmolality than crabs on the nearby open shore. In H. nudus the behavioural selection of a shelter appears to outweigh the physiological costs associated with osmotic regulation of the body fluids. Therefore, the distribution of H. nudus in estuaries may depend more on the availability of suitable habitats rather than the salinity tolerance of this species.

The ecophysiology of air-breathing in crabs with special reference to Gecarcoidea natalis.

PubMed

Morris, Steve

2002-04-01

To succeed on land rather than in water, crabs require a suite of physiological and morphological changes, and ultimately the ability to reproduce without access open water. Some species have modified gills to assist in gas exchange but accessory gas exchange organs, usually lungs, occur in many species. In accomplished air-breathers the lung becomes larger and more vascularised with pulmonary vessels directing oxygenated haemolymph to the heart. The relative abundance of O(2) in air promotes relative hypoventilation and thus an internal hypercapnia to drive CO(2) excretion. Land crabs have a dual circulation via either lungs or gills and shunting between the two may depend on respiratory media or exercise state. During their breeding migration on Christmas Island Gecarcoidea natalis maintained arterial Po(2) by branchial O(2) uptake, while pulmonary O(2) pressure was reduced; partly because exercise doubled relative haemolymph flow through the gills. Related species rely on elevated haemocyanin concentration and affinity for O(2) to assist uptake but this compromises unloading at the tissues and thus the aerobic scope of tissues. Aquatic crabs exchange salt and ammonia with water via the gills but in land crabs this is not possible. Birgus latro has adopted uricotelism but other species excrete ammonia in either the urine or as gas. Land crabs minimise urinary salt loss using a filtration-reabsorption system analogous to the kidney. Urine is redirected across the gills where salt reabsorption occurs in systems under hormonal control, although in G. natalis this is stimulatory and in B. latro inhibitory. While crabs occupy a range of habitats from aquatic to terrestrial, these species do not comprise a physiological continuum but across the crab taxa individual species possess appropriate and specific physiological features to survive in their individual habitat.

The Muskrat. The Not-So-Common Oyster. The Horseshoe Crab. The Blue Crab. Learning Experiences for Coastal and Oceanic Awareness Studies, Nos. 108, 109, 111, 201. [Project COAST].

ERIC Educational Resources Information Center

Delaware Univ., Newark. Coll. of Education.

Included are four units related to coastal and oceanic awareness. The units are: (1) The Muskrat; (2) The Not-So-Common Oyster; (3) The Horseshoe Crab; and (4) The Blue Crab. All four units are designed for elementary school students. Each unit contains teacher background materials, student activity materials, evaluation materials, transparency…

Use of Hyperspectral Imagery to Assess Cryptic Color Matching in Sargassum Associated Crabs.

PubMed

Russell, Brandon J; Dierssen, Heidi M

2015-01-01

Mats of the pelagic macroalgae Sargassum represent a complex environment for the study of marine camouflage at the air-sea interface. Endemic organisms have convergently evolved similar colors and patterns, but quantitative assessments of camouflage strategies are lacking. Here, spectral camouflage of two crab species (Portunus sayi and Planes minutus) was assessed using hyperspectral imagery (HSI). Crabs matched Sargassum reflectance across blue and green wavelengths (400-550 nm) and diverged at longer wavelengths. Maximum discrepancy was observed in the far-red (i.e., 675 nm) where Chlorophyll a absorption occurred in Sargassum and not the crabs. In a quantum catch color model, both crabs showed effective color matching against blue/green sensitive dichromat fish, but were still discernible to tetrachromat bird predators that have visual sensitivity to far red wavelengths. The two species showed opposing trends in background matching with relation to body size. Variation in model parameters revealed that discrimination of crab and background was impacted by distance from the predator, and the ratio of cone cell types for bird predators. This is one of the first studies to detail background color matching in this unique, challenging ecosystem at the air-sea interface.

Use of Hyperspectral Imagery to Assess Cryptic Color Matching in Sargassum Associated Crabs

PubMed Central

2015-01-01

Mats of the pelagic macroalgae Sargassum represent a complex environment for the study of marine camouflage at the air-sea interface. Endemic organisms have convergently evolved similar colors and patterns, but quantitative assessments of camouflage strategies are lacking. Here, spectral camouflage of two crab species (Portunus sayi and Planes minutus) was assessed using hyperspectral imagery (HSI). Crabs matched Sargassum reflectance across blue and green wavelengths (400–550 nm) and diverged at longer wavelengths. Maximum discrepancy was observed in the far-red (i.e., 675 nm) where Chlorophyll a absorption occurred in Sargassum and not the crabs. In a quantum catch color model, both crabs showed effective color matching against blue/green sensitive dichromat fish, but were still discernible to tetrachromat bird predators that have visual sensitivity to far red wavelengths. The two species showed opposing trends in background matching with relation to body size. Variation in model parameters revealed that discrimination of crab and background was impacted by distance from the predator, and the ratio of cone cell types for bird predators. This is one of the first studies to detail background color matching in this unique, challenging ecosystem at the air-sea interface. PMID:26352667

Crab and shellfish occurrences in the newly-grown mangrove habitats in southern Thailand

NASA Astrophysics Data System (ADS)

Yeesin, P.; Bautip, S.; Chesoh, S.

2018-04-01

Mangrove crabs and shellfish populating in Prince of Songkla University’s new grown mangrove forest were investigated from January 2011 to December 2011 and then repeated annually. A total of 12 species under 6 families of crab and 11 species under 5 families of shellfish were recorded. The most abundant family of crab was Sesarmidae (64.18 %), followed by Ocypodidae, Varunidae, Macrophthalmidae, Portunidae and Dotillidae. Episesarma mederi ( H. Milne Edwards, 1853) showed highest dominant species. In addition, the most dominant family of shellfish was Potamididae (13.79 %), followed by Melampidae, Assimineidae, Onchidiidae and Littorinidae. Sea snail (Cerithidae quadrata; Sowerby, 1866) presented the most dominant coastal mollusc species. Abundance and diversification crabs and mollusks show important component of food web of this type ecosystem. However, only trapped hold samples during low tide were collected but this preliminary finding enables reasonable specified regulation measures.

Toxicokinetics, disposition and metabolism of fluoxetine in crabs.

PubMed

Robert, Alexandrine; Schultz, Irvin R; Hucher, Nicolas; Monsinjon, Tiphaine; Knigge, Thomas

2017-11-01

The disposition and metabolism of fluoxetine in the European shore crab and the Dungeness crab were assessed. Crabs received intracardiac doses of either 0.13 μg/kg or 0.5 mg/kg fluoxetine, respectively. In addition, fluoxetine was administered to Metacarcinus cancer by oral gavage at 7.8 mg/kg. The distribution of fluoxetine was quantified in haemolymph and digestive gland for both crabs, as well as brain, muscle, and testis of Carcinus maenas, over 12 days. The metabolite norfluoxetine, was also measured in C. maenas. Fluoxetine was mainly found in lipid rich tissues. Distribution coefficients increased for digestive gland until three days after fluoxetine administration and then decreased until the end of the observations. The highest distribution coefficients were obtained for brain. Norfluoxetine displayed continuously high levels in digestive gland and brain. The strong decrease in fluoxetine and the concomitant increase in norfluoxetine demonstrates that decapod crustaceans metabolise fluoxetine into the more biologically active norfluoxetine. Fluoxetine levels in the haemolymph of M. cancer declined within 20 h, but showed a second peak 25 h later, suggesting remobilisation from tissues sequestering the compound. The steady state volume distribution and the total body clearance of fluoxetine were high, consistent with high diffusion of fluoxetine into the peripheral tissues and biotransformation as an important elimination pathway. Oral administration of fluoxetine prolonged its half-life in M. cancer, but bioavailability was low. These results confirm the high distribution into nervous tissue, extensive biotransformation into the highly active norfluoxetine and a half-life similar to that observed in vertebrates. Copyright © 2017 Elsevier Ltd. All rights reserved.

Juvenile Arrests, 1999. Juvenile Justice Bulletin.

ERIC Educational Resources Information Center

Snyder, Howard N.

This bulletin presents a summary and analysis of national and state juvenile arrest data for 1999. Data come from the FBI's annual "Crime in the United States" report, which offers the estimated number of crimes reported to law enforcement agencies. The 1999 murder rate was the lowest since 1966. Of the nearly 1,800 juveniles murdered in…

Juvenile Arrests, 2007. Juvenile Justice Bulletin

ERIC Educational Resources Information Center

Puzzanchera, Charles

2009-01-01

This Bulletin summarizes 2007 juvenile crime and arrest data reported by local law enforcement agencies across the country and cited in the FBI report, "Crime in the United States 2007." The Bulletin describes the extent and nature of juvenile crime that comes to the attention of the justice system. It serves as a baseline for comparison for…

Species Profiles. Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Pacific Northwest). Dungeness Crab.

DTIC Science & Technology

1986-08-01

variety of factors crab eggs has been linked to increased including depth, latitude, tempera- egg mortality because of mechanical ture, salinity and...time. crabs seem less dependent on epibenthic cover and can be found over more exposed substrates. Most crabs Temperature- Salinity Interactions remain...13 Salinity . .. ....... ........................................ 14 Temperature- Salinity Interactions. .. .... ....... ....... 14

76 FR 36511 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab; Amendment 3

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-22

...-BA22 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab; Amendment 3 AGENCY... the Atlantic Deep-Sea Red Crab Fishery Management Plan (FMP) (Amendment 3), incorporating a draft... current trap limit regulations state that red crab may not be harvested from gear other than a marked red...

Minorities in the Juvenile Justice System. 1999 National Report Series. Juvenile Justice Bulletin.

ERIC Educational Resources Information Center

Department of Justice, Washington, DC. Office of Juvenile Justice and Delinquency Prevention.

This report provides data on minorities in the juvenile justice system. Minority juveniles are significantly over-represented in the juvenile justice system. In 1997, minorities made up about one-third of the juvenile population nationwide but accounted for nearly two-thirds of the detained and committed population in secure juvenile facilities.…

Oxygen uptake by embryos and ovigerous females of two intertidal crabs, Heterozius rotundifrons (Belliidae) and Cyclograpsus lavauxi (Grapsidae): scaling and the metabolic costs of reproduction.

PubMed

Taylor, H H; Leelapiyanart, N

2001-03-01

Heterozius rotundifrons and Cyclograpsus lavauxi are crabs of similar size, whose intertidal habitats overlap. They differ in the number and size of their eggs. A 2 g ovigerous H. rotundifrons incubates 675 large yolky eggs (mean single-egg mass 269 microg; egg clutch 9.15 % of mass of female crab; increasing to 435 microg and 13.4 % at hatching). The egg clutch of a 2 g C. lavauxi is larger (15.4 % of crab mass increasing to 18.9 % at hatching) and contains more numerous (28 000), smaller (10.9 microg increasing to 20.3 microg) eggs. The longer development time of the larger eggs (194 days versus 56 days at 15 degrees C) results from a delayed increase in metabolic rate (diapause) and not metabolic scaling. On the basis of the total mass of single eggs, the mass-specific metabolic rates of early embryonic stages of H. rotundifrons (0.72 micromol g(-1 )h(-1) for the blastula stage at 15 degrees C) and C. lavauxi (1.13 micromol g(-1 )h(-1)) were similar to those of the adult female crabs (0.70 micromol g(-1 )h(-1) for H. rotundifrons and 0.91 micromol g(-1 )h(-1) for C. lavauxi) and increased 13- and 10-fold, respectively, by the time of hatching. Thus, early embryonic metabolic rates were much lower than expected from their mass, but the metabolic rates of pre-hatching embryos were consistent with the allometry of juveniles and adults. Possible interpretations of this apparently anomalous scaling of embryonic metabolic rates are discussed. Mass-specific rates of oxygen consumption by ovigerous females (including the eggs) of both species were higher than for non-ovigerous crabs, in water and in air, and increased greatly during the development of the eggs. This difference was attributable mainly to the increasing metabolic rates of the attached embryos, but early ovigerous crabs (blastula stage) of both species also demonstrated a small elevation in metabolic rate by the crab itself, i.e. a metabolic cost of egg-bearing. In contrast, the elevation of the rate of

Appearance and partial purification of a high molecular weight protein in crabs exposed to saxitoxin.

PubMed

Barber, K G; Kitts, D D; Townsley, P M; Smith, D S

1988-01-01

This paper provides evidence for a protein component which appears to be involved in the seasonal resistance of small shore crabs, Hemigrapsus oregonesis and Hemigrapsus nudus to saxitoxin, a principle neurotoxin involved in paralytic shellfish poisoning (PSP). This unique protein complex was isolated and partially purified by ion exchange chromatography using DEAE-cellulose from visceral tissue extracts of resistant crabs. The complex was absent in control crabs that were sensitive to saxitoxin. In addition, the protein complex was induced in the crab after acute administration of low doses of saxitoxin. Results indicate that the protein complex is acidic in nature and has an apparent mol. wt of 145,000.

Meet EPA researcher Dawn King

EPA Pesticide Factsheets

Research microbiologist Dawn King works in EPA’s National Exposure Research Laboratory where she identifies and assesses the health risk of microbial pathogens in water. This is her researchers at work profile.

Imaging the Crab nebula when it is flaring in gamma-rays

NASA Astrophysics Data System (ADS)

De Luca, Andrea

2012-10-01

One of the most intriguing results of the gamma-ray instruments currently in orbit has been the detection of powerful flares from the Crab Nebula in September 2010. In April 2011 a similar flare, lasting several days, made the nebula the brightest source in the gamma-ray sky. A critical reassessment of long term behavior of the Crab flux clearly showed that both Agile and Fermi had already detected similar events in October 2007 and February 2009, pointing to a recurrence time of once per year. A HST observing strategy must be set up to react promptly to any possible new brightening of the Crab in gamma rays. In September 2010 we requested a DD observation which was promptly accepted and carried out. However, the lack of a suitable reference image hampered our efforts to pinpoint the sites of possible variability inside the nebula. Thus, while now we ask for a triggered TOO observation of the Crab Nebula with ACS/WFC in case a gamma-ray flare is announced by the Agile and/or Fermi missions, we are also organizing a regular {monthly} monitoring of the source both in X-ray and optical through a joint Chandra-HST proposal.

Non-indigenous predators threaten ecosystem engineers: Interactive effects of green crab and oyster size on American oyster mortality.

PubMed

Pickering, Tyler R; Poirier, Luke A; Barrett, Timothy J; McKenna, Shawn; Davidson, Jeff; Quijón, Pedro A

2017-06-01

Non-indigenous green crabs (Carcinus maenas) are emerging as important predators of autogenic engineers like American oysters (Crassostrea virginica) throughout the eastern seaboard of Canada and the United States. To document the spreading distribution of green crabs, we carried out surveys in seven sites of Prince Edward Island during three fall seasons. To assess the potential impact of green crabs on oyster mortality in relation to predator and prey size, we conducted multiple predator-prey manipulations in the field and laboratory. The surveys confirmed an ongoing green crab spread into new productive oyster habitats while rapidly increasing in numbers in areas where crabs had established already. The experiments measured mortality rates on four sizes of oysters exposed to three sizes of crab, and lasted 3-5 days. The outcomes of experiments conducted in Vexar ® bags, laboratory tanks and field cages were consistent and were heavily dependent on both crab size and oyster size: while little predation occurred on large oysters, large and medium green crabs preyed heavily on small sizes. Oysters reached a refuge within the 35-55 mm shell length range; below that range, oysters suffered high mortality due to green crab predation and thus require management measures to enhance their survival. These results are most directly applicable to aquaculture operations and restoration initiatives but have implications for oyster sustainability. Copyright © 2017 Elsevier Ltd. All rights reserved.

Juvenile Arrests 1996. Juvenile Justice Bulletin.

ERIC Educational Resources Information Center

Snyder, Howard N.

In 1996, law enforcement agencies in the United States made an estimated 2.9 million arrests of persons under the age of 18. According to Federal Bureau of Investigation (FBI) figures, juveniles accounted for 19% of all arrests and 19% of all violent crime in 1996. The substantial growth in juvenile crime that began in the late 1980s peaked in…

American alligator digestion rate of blue crabs and its implications for stomach contents analysis

USGS Publications Warehouse

Nifong, James C.; Rosenblatt, Adam E.; Johnson, Nathan A.; Barichivich, William; Silliman, Brian; Heithaus, Michael R.

2012-01-01

Stomach contents analysis (SCA) provides a snap-shot observation of a consumer's diet. Interpretation of SCA data can be complicated by many factors, including variation in gastric residence times and digestion rates among prey taxa. Although some SCA methods are reported to efficiently remove all stomach contents, the effectiveness of these techniques has rarely been tested for large irregular shaped prey with hard exoskeletons. We used a controlled feeding trial to estimate gastric residency time and decomposition rate of a large crustacean prey item, the Blue Crab (Callinectes sapidus), which is consumed by American Alligators (Alligator mississippiensis), an abundant apex predator in coastal habitats of the southeastern United States. The decomposition rate of C. sapidus in the stomachs of A. mississippiensis followed a predictable pattern, and some crab pieces remained in stomachs for at least 14 days. We also found that certain portions of C. sapidus were prone to becoming caught within the stomach or esophagus, meaning not all crab parts are consistently recovered using gastric lavage techniques. However, because the state of decomposition of crabs was predictable, it is possible to estimate time since consumption for crabs recovered from wild alligators. This information, coupled with a detailed understanding of crab distributions and alligator movement tactics could help elucidate patterns of cross-ecosystem foraging by the American Alligator in coastal habitats

Spatial and temporal patterns of subtidal and intertidal crabs excursions

NASA Astrophysics Data System (ADS)

Silva, A. C. F.; Boaventura, D. M.; Thompson, R. C.; Hawkins, S. J.

2014-01-01

Highly mobile predators such as fish and crabs are known to migrate from the subtidal zone to forage in the intertidal zone at high-tide. The extent and variation of these habitat linking movements along the vertical shore gradient have not been examined before for several species simultaneously, hence not accounting for species interactions. Here, the foraging excursions of Carcinus maenas (L.), Necora puber (Linnaeus, 1767) and Cancer pagurus (Linnaeus, 1758) were assessed in a one-year mark-recapture study on two replicated rocky shores in southwest U.K. A comparison between the abundance of individuals present on the shore at high-tide with those present in refuges exposed at low-tide indicated considerable intertidal migration by all species, showing strong linkage between subtidal and intertidal habitats. Estimates of population size based on recapture of marked individuals indicated that an average of ~ 4000 individuals combined for the three crab species, can be present on the shore during one tidal cycle. There was also a high fidelity of individuals and species to particular shore levels. Underlying mechanisms for these spatial patterns such as prey availability and agonistic interactions are discussed. Survival rates were estimated using the Cormack-Jolly-Seber model from multi-recapture analysis and found to be considerably high with a minimum of 30% for all species. Growth rates were found to vary intraspecifically with size and between seasons. Understanding the temporal and spatial variations in predation pressure by crabs on rocky shores is dependent on knowing who, when and how many of these commercially important crab species depend on intertidal foraging. Previous studies have shown that the diet of these species is strongly based on intertidal prey including key species such as limpets; hence intertidal crab migration could be associated with considerable impacts on intertidal assemblages.

Understanding to Hierarchical Microstructures of Crab (Chinese hairy) Shell as a Natural Architecture

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

Chuanqiang, Zhou; Xiangxiang, Gong; School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou

This work was done to better understand the microstructures, composition and mechanical properties of Chinese hairy crab shell. For fully revealing its hierarchical microstructure, the crab shell was observed with electron microscope under different magnifications from different facets. XRD, EDS, FTIR and TGA techniques have been used to characterize the untreated and chemically-treated crab shells, which provided enough information to determine the species and relative content of components in this biomaterial. Combined the microstructures with constituents analysis, the structural principles of crab shell was detailedly realized from different structural levels beyond former reports. To explore the relationship between structure andmore » function, the mechanical properties of shell have been measured through performing tensile tests. The contributions of organics and minerals in shell to the mechanical properties were also discussed by measuring the tensile strength of de-calcification samples treated with HCl solution.« less

Purification, cloning, expression and immunological analysis of Scylla serrata arginine kinase, the crab allergen.

PubMed

Shen, Yuan; Cao, Min-Jie; Cai, Qiu-Feng; Su, Wen-Jin; Yu, Hui-Lin; Ruan, Wei-Wei; Liu, Guang-Ming

2011-05-01

Although crustaceans have been reported to be one of the most common causes of IgE-mediated allergic reactions, there are no reports about the characterization and identification of arginine kinase (AK) from the mud crab (Scylla serrata) as allergen. In the present study, the purification, molecular cloning, expression and immunological analyses of the IgE allergen AK from the mud crab were investigated. The results showed that cloned DNA fragments of AK from the mud crab had open reading frames of 1021 bp, predicted to encode proteins with 356 amino acid residues. Sequence alignment revealed that mud crab AK shares high homology with other crustacean species. Mud crab AK gene was further recombined with the vector of pGEX-4T-3 and expressed in Escherichia coli BL 21. 2-D electrophoresis suggested that native AK (nAK) and recombinant AK (rAK) shared the same molecular weight of 40 kDa, and the pI is 6.5 and 6.3, respectively. The nAK and rAK were further confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Immunoblotting analysis and colloidal gold immunochromatographic assay (GICA) using sera from subjects with crustacean allergy confirmed that the nAK and rAK reacted positively with these sera, indicating AK is a specific allergen of mud crab. Both of purified nAK and rAK reacted positively with sera from subjects with crustacean allergy in immunoblotting and GICA analysis, indicating AK is a common allergen of mud crab. In vitro expressed AK is proposed as a source of the protein for immunological or clinical studies. Copyright © 2011 Society of Chemical Industry.

Differences in Size Selectivity and Catch Composition Between Two Bottom Trawls Used in High-Arctic Surveys of Bottom Fishes, Crabs and Other Demersal Macrofauna

NASA Astrophysics Data System (ADS)

Lauth, R.; Norcross, B.; Kotwicki, S.; Britt, L.

2016-02-01

Long-term monitoring of the high-Arctic marine biota is needed to understand how the ecosystem is changing in response to climate change, diminishing sea-ice, and increasing anthropogenic activity. Since 1959, bottom trawls (BT) have been a primary research tool for investigating fishes, crabs and other demersal macrofauna in the high-Arctic. However, sampling gears, methodologies, and the overall survey designs used have generally lacked consistency and/or have had limited spatial coverage. This has restricted the ability of scientists and managers to effectively use existing BT survey data for investigating historical trends and zoogeographic changes in high-Arctic marine populations. Two different BTs currently being used for surveying the high-Arctic are: 1) a small-mesh 3-m plumb-staff beam trawl (PSBT), and 2) a large-mesh 83-112 Eastern bottom trawl (EBT). A paired comparison study was conducted in 2012 to compare catch composition and the sampling characteristics of the two different trawl gears, and a size selectivity ratio statistic was used to investigate how the probability of fish and crab retention differs between the EBT and PBST. Obvious contrasting characteristics of the PSBT and EBT were mesh size, area-swept, tow speed, and vertical opening. The finer mesh and harder bottom-tending characteristics of the PSBT retained juvenile fishes and other smaller macroinvertebrates and it was also more efficient catching benthic infauna that were just below the surface. The EBT had a larger net opening with greater tow duration at a higher speed that covered a potentially wider range of benthic habitats during a single tow, and it was more efficient at capturing larger and more mobile organisms, as well as organisms that were further off bottom. The ratio statistic indicated large differences in size selectivity between the two gears for both fish and crab. Results from this investigation will provide a framework for scientists and mangers to better

Exceptional appendage and soft-tissue preservation in a Middle Triassic horseshoe crab from SW China.

PubMed

Hu, Shixue; Zhang, Qiyue; Feldmann, Rodney M; Benton, Michael J; Schweitzer, Carrie E; Huang, Jinyuan; Wen, Wen; Zhou, Changyong; Xie, Tao; Lü, Tao; Hong, Shuigen

2017-10-26

Horseshoe crabs are classic "living fossils", supposedly slowly evolving, conservative taxa, with a long fossil record back to the Ordovician. The evolution of their exoskeleton is well documented by fossils, but appendage and soft-tissue preservation is extremely rare. Here we analyse details of appendage and soft-tissue preservation in Yunnanolimulus luopingensis, a Middle Triassic (ca. 244 million years old) horseshoe crab from Yunnan Province, SW China. The remarkable preservation of anatomical details including the chelicerae, five pairs of walking appendages, opisthosomal appendages with book gills, muscles, and fine setae permits comparison with extant horseshoe crabs. The close anatomical similarity between the Middle Triassic horseshoe crabs and their recent analogues documents anatomical conservatism for over 240 million years, suggesting persistence of lifestyle. The occurrence of Carcinoscorpius-type claspers on the first and second walking legs in male individuals of Y. luopingensis indicates that simple chelate claspers in males are plesiomorphic for horseshoe crabs, and the bulbous claspers in Tachypleus and Limulus are derived.

Size-frequency distribution, growth, and mortality of snow crab (Chionoecetes opilio) and arctic lyre crab (Hyas coarctatus) in the chukchi sea from 2009 to 2013

NASA Astrophysics Data System (ADS)

Groß, Jasmin; Konar, Brenda; Brey, Thomas; Grebmeier, Jacqueline M.

2017-10-01

The snow crab Chionoecetes opilio and Arctic lyre crab Hyas coarctatus are prominent members of the Chukchi Sea epifaunal community. A better understanding of their life history will aid in determining their role in this ecosystem in light of the changing climate and resource development. In this study, the size frequency distribution, growth, and mortality of these two crab species was examined in 2009, 2010, 2012, and 2013 to determine temporal and spatial patterns within the eastern Chukchi Sea, and to identify potential environmental drivers of the observed patterns. Temporally, the mean size of both sexes of C. opilio and H. coarctatus decreased significantly from 2009 to 2013, with the number of rare maximum sized organisms decreasing significantly to near absence in the latter two study years. Spatially, the mean size of male and female crabs of both species showed a latitudinal trend, decreasing from south to north in the investigation area. Growth of both sexes of C. opilio and H. coarctatus was linear over the sampled size range, and mortality was highest in the latter two study years. Life history features of both species related to different environmental parameters in different years, ranging from temperature, the sediment carbon to nitrogen ratio of the organic content, and sediment grain size distribution. Likely explanations for the observed temporal and spatial variability are ontogenetic migrations of mature crabs to warmer areas possibly due to cooler water temperatures in the latter two study years, or interannual fluctuations, which have been reported for C. opilio populations in other areas where successful waves of recruitment were estimated to occur in eight year intervals. Further research is suggested to determine if the spatial and temporal patterns found in this study are part of the natural variability in this system or if they are an indication of long-term trends.

Ugiuvangmiut Quliapyuit = King Island Tales. Eskimo History and Legends from Bering Strait.

ERIC Educational Resources Information Center

Kaplan, Lawrence D., Ed.

The collection of native tales from King Island, Alaska, contains tales told originally in Inupiaq Eskimo by seven native elders. Introductory sections provide background information on the storytellers, King Island Village and its people, traditional life there, and the language of the King Islanders. The 25 tales are divided into groups:…

75 FR 7435 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-19

.... 100105009-0053-01] RIN 0648-AY51 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications AGENCY: National Marine Fisheries Service (NMFS... comments. SUMMARY: NMFS proposes 2010 specifications for the Atlantic deep-sea red crab fishery, including...

75 FR 27219 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-14

.... 100105009-0167-02] RIN 0648-AY51 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications AGENCY: National Marine Fisheries Service (NMFS... final specifications for the 2010 Atlantic deep- sea red crab fishery, including a target total...

Are antipredator behaviours of hatchery Salmo salar juveniles similar to wild juveniles?

PubMed

Salvanes, A G V

2017-05-01

This study explores how antipredator behaviour of juvenile Atlantic salmon Salmo salar developed during conventional hatchery rearing of eggs from wild brood stock, compared with the behaviour of wild-caught juveniles from the same population. Juveniles aged 1+ years were tested in two unfamiliar environments; in one S. salar were presented with simulated predator attacks and in the other they were given the opportunity to explore an open-field arena. No difference was found in their spontaneous escape responses or ventilation rate (reflex responses) after simulated predator attacks. Hatchery-reared juveniles were more risk-prone in their behaviours than wild-caught individuals. Hatchery juveniles stayed less time in association with shelter. In the open-field arena, hatchery juveniles were more active than wild juveniles. Hatchery juveniles were also immobile for less time and spent a shorter amount of time than wild juveniles in the fringe of the open-field arena. Salmo salar size had no effect on the observed behaviour. Overall, this study provides empirical evidence that one generation of hatchery rearing does not change reflex responses associated with threats, whereas antipredator behaviour, typically associated with prior experience, was less developed in hatchery-reared than in wild individuals. © 2017 The Fisheries Society of the British Isles.

CRAB3: Establishing a new generation of services for distributed analysis at CMS

NASA Astrophysics Data System (ADS)

Cinquilli, M.; Spiga, D.; Grandi, C.; Hernàndez, J. M.; Konstantinov, P.; Mascheroni, M.; Riahi, H.; Vaandering, E.

2012-12-01

In CMS Computing the highest priorities for analysis tools are the improvement of the end users’ ability to produce and publish reliable samples and analysis results as well as a transition to a sustainable development and operations model. To achieve these goals CMS decided to incorporate analysis processing into the same framework as data and simulation processing. This strategy foresees that all workload tools (TierO, Tier1, production, analysis) share a common core with long term maintainability as well as the standardization of the operator interfaces. The re-engineered analysis workload manager, called CRAB3, makes use of newer technologies, such as RESTFul based web services and NoSQL Databases, aiming to increase the scalability and reliability of the system. As opposed to CRAB2, in CRAB3 all work is centrally injected and managed in a global queue. A pool of agents, which can be geographically distributed, consumes work from the central services serving the user tasks. The new architecture of CRAB substantially changes the deployment model and operations activities. In this paper we present the implementation of CRAB3, emphasizing how the new architecture improves the workflow automation and simplifies maintainability. In particular, we will highlight the impact of the new design on daily operations.

A crab swarm at an ecological hotspot: patchiness and population density from AUV observations at a coastal, tropical seamount.

PubMed

Pineda, Jesús; Cho, Walter; Starczak, Victoria; Govindarajan, Annette F; Guzman, Héctor M; Girdhar, Yogesh; Holleman, Rusty C; Churchill, James; Singh, Hanumant; Ralston, David K

2016-01-01

A research cruise to Hannibal Bank, a seamount and an ecological hotspot in the coastal eastern tropical Pacific Ocean off Panama, explored the zonation, biodiversity, and the ecological processes that contribute to the seamount's elevated biomass. Here we describe the spatial structure of a benthic anomuran red crab population, using submarine video and autonomous underwater vehicle (AUV) photographs. High density aggregations and a swarm of red crabs were associated with a dense turbid layer 4-10 m above the bottom. The high density aggregations were constrained to 355-385 m water depth over the Northwest flank of the seamount, although the crabs also occurred at lower densities in shallower waters (∼280 m) and in another location of the seamount. The crab aggregations occurred in hypoxic water, with oxygen levels of 0.04 ml/l. Barcoding of Hannibal red crabs, and pelagic red crabs sampled in a mass stranding event in 2015 at a beach in San Diego, California, USA, revealed that the Panamanian and the Californian crabs are likely the same species, Pleuroncodes planipes, and these findings represent an extension of the southern endrange of this species. Measurements along a 1.6 km transect revealed three high density aggregations, with the highest density up to 78 crabs/m(2), and that the crabs were patchily distributed. Crab density peaked in the middle of the patch, a density structure similar to that of swarming insects.

A crab swarm at an ecological hotspot: patchiness and population density from AUV observations at a coastal, tropical seamount

PubMed Central

Cho, Walter; Starczak, Victoria; Govindarajan, Annette F.; Guzman, Héctor M.; Girdhar, Yogesh; Holleman, Rusty C.; Churchill, James; Singh, Hanumant; Ralston, David K.

2016-01-01

A research cruise to Hannibal Bank, a seamount and an ecological hotspot in the coastal eastern tropical Pacific Ocean off Panama, explored the zonation, biodiversity, and the ecological processes that contribute to the seamount’s elevated biomass. Here we describe the spatial structure of a benthic anomuran red crab population, using submarine video and autonomous underwater vehicle (AUV) photographs. High density aggregations and a swarm of red crabs were associated with a dense turbid layer 4–10 m above the bottom. The high density aggregations were constrained to 355–385 m water depth over the Northwest flank of the seamount, although the crabs also occurred at lower densities in shallower waters (∼280 m) and in another location of the seamount. The crab aggregations occurred in hypoxic water, with oxygen levels of 0.04 ml/l. Barcoding of Hannibal red crabs, and pelagic red crabs sampled in a mass stranding event in 2015 at a beach in San Diego, California, USA, revealed that the Panamanian and the Californian crabs are likely the same species, Pleuroncodes planipes, and these findings represent an extension of the southern endrange of this species. Measurements along a 1.6 km transect revealed three high density aggregations, with the highest density up to 78 crabs/m2, and that the crabs were patchily distributed. Crab density peaked in the middle of the patch, a density structure similar to that of swarming insects. PMID:27114859

Modelling the ArH+ emission from the Crab nebula

NASA Astrophysics Data System (ADS)

Priestley, F. D.; Barlow, M. J.; Viti, S.

2017-12-01

We have performed combined photoionization and photodissociation region (PDR) modelling of a Crab nebula filament subjected to the synchrotron radiation from the central pulsar wind nebula, and to a high flux of charged particles; a greatly enhanced cosmic-ray ionization rate over the standard interstellar value, ζ0, is required to account for the lack of detected [C I] emission in published Herschel SPIRE FTS observations of the Crab nebula. The observed line surface brightness ratios of the OH+ and ArH+ transitions seen in the SPIRE FTS frequency range can only be explained with both a high cosmic-ray ionization rate and a reduced ArH+ dissociative recombination rate compared to that used by previous authors, although consistent with experimental upper limits. We find that the ArH+/OH+ line strengths and the observed H2 vibration-rotation emission can be reproduced by model filaments with nH = 2 × 104 cm-3, ζ = 107ζ0 and visual extinctions within the range found for dusty globules in the Crab nebula, although far-infrared emission from [O I] and [C II] is higher than the observational constraints. Models with nH = 1900 cm-3 underpredict the H2 surface brightness, but agree with the ArH+ and OH+ surface brightnesses and predict [O I] and [C II] line ratios consistent with observations. These models predict HeH+ rotational emission above detection thresholds, but consideration of the formation time-scale suggests that the abundance of this molecule in the Crab nebula should be lower than the equilibrium values obtained in our analysis.

Multispecies modeling for adaptive management of horseshoe crabs and red knots in the Delaware Bay

USGS Publications Warehouse

McGowan, Conor P.; Smith, David; Sweka, John A.; Martin, Julien; Nichols, James D.; Wong, Richard; Lyons, James E.; Niles, Lawrence J.; Kalasz, Kevin; Brust, Jeffrey; Klopfer, Michelle; Spear, Braddock

2011-01-01

Adaptive management requires that predictive models be explicit and transparent to improve decisions by comparing management actions, directing further research and monitoring, and facilitating learning. The rufa subspecies of red knots (Calidris canutus rufa), which has recently exhibited steep population declines, relies on horseshoe crab (Limulus polyphemus) eggs as their primary food source during stopover in Delaware Bay during spring migration. We present a model with two different parameterizations for use in the adaptive management of horseshoe crab harvests in the Delaware Bay that links red knot mass gain, annual survival, and fecundity to horseshoe crab dynamics. The models reflect prevailing hypotheses regarding ecological links between these two species. When reported crab harvest from 1998 to 2008 was applied, projections corresponded to the observed red knot population abundances depending on strengths of the demographic relationship between these species. We compared different simulated horseshoe crab harvest strategies to evaluate whether, given this model, horseshoe crab harvest management can affect red knot conservation and found that restricting harvest can benefit red knot populations. Our model is the first to explicitly and quantitatively link these two species and will be used within an adaptive management framework to manage the Delaware Bay system and learn more about the specific nature of the linkage between the two species.

Mercury burdens in Chinese mitten crabs (Eriocheir sinensis) in three tributaries of southern San Francisco Bay, California, USA

USGS Publications Warehouse

Hui, C.A.; Rudnick, D.; Williams, E.

2005-01-01

Chinese mitten crabs (Eriocheir sinensis), endemic to Asia, were first reported in the San Francisco Bay in 1992. They are now established in nearly all San Francisco Bay tributaries. These crabs accumulate more metals, such as mercury, than crustaceans living in the water column. Because their predators include fish, birds, mammals and humans, their mercury burdens have an exceptional potential to impact the ecosystem and public health. We sought to elucidate the potential threat of mitten crab mercury burdens in three adjacent streams in southern San Francisco Bay, one of which is known to be contaminated with mercury. Mitten crabs had hepatopancreas concentrations of total mercury and methylmercury that did not differ among streams. The maximum burden we measured was below the action level of 1 ppm recommended by the USEPA. Hepatopancreas concentrations of methylmercury declined with increasing crab size, suggesting a mechanism for mercury excretion and that predators might reduce mercury exposure if they select larger crabs. Because mercury may be heterogeneously distributed among tissues, estimation of the impacts of crab mercury burdens on the environment requires more data on the feeding preferences of predators. Hepatopancreas concentrations of mercury decline with crab size, which may have important consequences for bio-magnification in food webs. ?? 2004 Elsevier Ltd. All rights reserved.

75 FR 49420 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-13

.... 100513223-0289-02] RIN 0648-AY88 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications In- season Adjustment AGENCY: National Marine...-sea (DAS) allocation for the Atlantic deep- sea red crab fishery that were implemented in May 2010...

a Surprise from the Pulsar in the Crab Nebula

NASA Astrophysics Data System (ADS)

1995-11-01

New observations of the spectrum of the rapidly spinning neutron star (the `pulsar') in the Crab Nebula have been carried out with the ESO 3.5-metre New Technology Telescope (NTT) by a group of Italian astronomers [1]. Because of greatly improved spectral resolution which allows to register even very fine details in the pulsar's spectrum, they are able to determine for the first time with high accuracy the overall dependance of the emission on wavelength, i.e. the `shape' of the spectrum. Quite unexpectedly, they also detect a hitherto unknown 100 A (10 nm) broad `absorption dip', which can be securely attributed to the pulsar. These results open an exciting new window for the study of the extreme physical processes close to a pulsar. The Nature of Pulsars It is estimated that there may be as many as 100 million neutron stars in our Galaxy. A neutron star is the superdense remnant of the extremely violent supernova explosion that occurs at the end of the life of a comparatively massive star. In fact, all stars that are more than about 6 times heavier than the Sun are believed to end their lives as supernovae. During the explosion, the central core of the dying star collapses in a few milliseconds and the matter at the centre is compressed to a density comparable to that of an atomic nucleus. Due to the enormous inward pressure, the atomic particles are squeezed together into a kind of neutron jam. The outcome is the formation of a neutron star with a diameter of 10-15 kilometres, weighing as much as the Sun. In accordance with the physical law that implies that the rotation momentum of the exploding star must be conserved, newborn neutron stars will rotate very rapidly around their axis, in some cases as fast as 100 times per second. In the same way, the new neutron star is expected to possess a strong magnetic field. Of these myriads of neutron stars, about 700 have been observed to emit radio pulses (hence the name `pulsar'). A few of these can also be detected

75 FR 35435 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-22

.... 100513223-0254-01] RIN 0648-AY88 Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications In- season Adjustment AGENCY: National Marine... deep-sea red crab fishery, including a target total allowable catch (TAC) and a fleet-wide days-at-sea...

Elemental compositions of crab and snail shells from the Kueishantao hydrothermal field in the southwestern Okinawa Trough

NASA Astrophysics Data System (ADS)

Zeng, Zhigang; Ma, Yao; Wang, Xiaoyuan; Chen, Chen-Tung Arthur; Yin, Xuebo; Zhang, Suping; Zhang, Junlong; Jiang, Wei

2018-04-01

To reveal differences in the behavior of benthic vent animals, and the sources and sinks of biogeochemical and fluid circulations, it is necessary to constrain the chemical characteristics of benthic animals from seafloor hydrothermal fields. We measured the abundances of 27 elements in shells of the crab Xenograpsus testudinatus and the snail Anachis sp., collected from the Kueishantao hydrothermal field (KHF) in the southwestern Okinawa Trough, with the aim of improving our understanding of the compositional variations between individual vent organisms, and the sources of the rare earth elements (REEs) in their shells. The Mn, Hg, and K concentrations in the male X. testudinatus shells are found to be higher than those in female crab shells, whereas the reverse is true for the accumulation of B, implying that the accumulation of K, Mn, Hg, and B in the crab shells is influenced by sex. This is inferred to be a result of the asynchronous molting of the male and female crab shells. Snail shells are found to have higher Ca, Al, Fe, Ni, and Co concentrations than crab shells. This may be attributed to different metal accumulation times. The majority of the light rare earth element (LREE) distribution patterns in the crab and snail shells are similar to those of Kueishantao vent fluids, with the crab and snail shells also exhibiting LREE enrichment, implying that the LREEs contained in crab and snail shells in the KHF are derived from vent fluids.

Characterization of microRNAs in Mud Crab Scylla paramamosain under Vibrio parahaemolyticus Infection

PubMed Central

Li, Chuanbiao; Zhang, Zhao; Zhou, Lizhen; Wang, Shijia; Wang, Shuqi; Zhang, Yueling; Wen, Xiaobo

2013-01-01

Background Infection of bacterial Vibrio parahaemolyticus is common in mud crab farms. However, the mechanisms of the crab’s response to pathogenic V. parahaemolyticus infection are not fully understood. MicroRNAs (miRNAs) are a class of small noncoding RNAs that function as regulators of gene expression and play essential roles in various biological processes. To understand the underlying mechanisms of the molecular immune response of the crab to the pathogens, high-throughput Illumina/Solexa deep sequencing technology was used to investigate the expression profiles of miRNAs in S . paramamosain under V. parahaemolyticus infection. Methodology/Principal Findings Two mixed RNA pools of 7 tissues (intestine, heart, liver, gill, brain, muscle and blood) were obtained from V. parahaemolyticus infected crabs and the control groups, respectively. By aligning the sequencing data with known miRNAs, we characterized 421 miRNA families, and 133 conserved miRNA families in mud crab S . paramamosain were either identical or very similar to existing miRNAs in miRBase. Stem-loop qRT-PCRs were used to scan the expression levels of four randomly chosen differentially expressed miRNAs and tissue distribution. Eight novel potential miRNAs were confirmed by qRT-PCR analysis and the precursors of these novel miRNAs were verified by PCR amplification, cloning and sequencing in S . paramamosain . 161 miRNAs (106 of which up-regulated and 55 down-regulated) were significantly differentially expressed during the challenge and the potential targets of these differentially expressed miRNAs were predicted. Furthermore, we demonstrated evolutionary conservation of mud crab miRNAs in the animal evolution process. Conclusions/Significance In this study, a large number of miRNAs were identified in S . paramamosain when challenged with V. parahaemolyticus, some of which were differentially expressed. The results show that miRNAs might play some important roles in regulating gene expression in

Black swans and dragon kings: A unified model

NASA Astrophysics Data System (ADS)

Eliazar, Iddo

2017-09-01

The term “black swan” is a metaphor for outlier events whose statistics are characterized by Pareto's Law and by Zipf's Law; namely, statistics governed by power-law tails. The term “dragon king” is a metaphor for a singular outlier event which, in comparison with all other outlier events, is in a league of its own. As an illustrative example consider the wealth of a family that is sampled at random from a medieval society: the nobility constitutes the black-swan category, and the royal family constitutes the dragon-king category. In this paper we present and analyze a dynamical model that generates, universally and jointly, black swans and dragon kings. According to this model, growing from the microscopic scale to the macroscopic scale, black swans and dragon kings emerge together and invariantly with respect to initial conditions.

Maine belowground marsh destruction from the European green crab documented by computer-aided tomography

EPA Science Inventory

Invasive European green crab (Carcinus maenus) populations have exploded with devastating losses to Maine’s intertidal resources including soft-shell clams, eelgrass beds, and salt marshes. This project quantified the green crab abundance in three different marsh locations ...

Simulation of Crab Waist Collisions In DA$$\\Phi$$NE With KLOE-2 Interaction Region

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

Zobov, M.; Drago, A.; Gallo, A.

2015-06-24

After the successful completion of the SIDDHARTA experiment run with crab waist collisions, the electron-positron collider DAΦNE has started routine operations for the KLOE-2 detector. The new interaction region also exploits the crab waist collision scheme, but features certain complications including the experimental detector solenoid, compensating anti-solenoids, and tilted quadrupole magnets. We have performed simulations of the beam-beam collisions in the collider taking into account the real DAΦNE nonlinear lattice. In particular, we have evaluated the effect of crab waist sextupoles and beam-beam interactions on the DAΦNE dynamical aperture and energy acceptance, and estimated the luminosity that can be potentiallymore » achieved with and without crab waist sextupoles in the present working conditions. A numerical analysis has been performed in order to propose possible steps for further luminosity increase in DAΦNE such as a better working point choice, crab sextupole strength optimization, correction of the phase advance between the sextupoles and the interaction region. The proposed change of the e- ring working point was implemented and resulted in a significant performance increase.« less

Acute exposure to high environmental ammonia (HEA) triggers the emersion response in the green shore crab.

PubMed

Zimmer, Alex M; Wood, Chris M

2017-02-01

The physiological effects of high environmental ammonia (HEA) exposure have been well documented in many aquatic species. In particular, it has recently been demonstrated that exposure to ammonia in fish leads to a similar hyperventilatory response as observed during exposure to hypoxia. In littoral crabs, such as the green crab (Carcinus maenas), exposure to severe hypoxia triggers an emersion response whereby crabs escape hypoxia to breathe air. We hypothesized that exposure to HEA in green crabs would lead to a similar behavioural response which is specific to ammonia. Using an experimental arena containing a rock bed onto which crabs could emerse, we established that exposure to HEA (4mmol/l NH 4 HCO 3 ) for 15min triggers emersion in crabs. In experiments utilizing NaHCO 3 controls and NH 4 HCO 3 injections, we further determined that emersion was triggered specifically by external ammonia and was independent of secondary acid-base or respiratory disturbances caused by HEA. We then hypothesized that emersion from HEA provides a physiological benefit, similar to emersion from hypoxia. Exposure to 15min of HEA without emersion (no rock bed present) caused significant increases in arterial haemolymph total ammonia (T amm ), pH, and [HCO 3 - ] . When emersion was allowed, arterial haemolymph T amm and [HCO 3 - ] increased, but no alkalosis developed. Moreover, emersion decreased haemolymph partial pressure of NH 3 relative to crabs which could not emerse. Overall, we demonstrate a novel behavioural response to HEA exposure in crabs which we propose may share similar mechanistic pathways with the emersion response triggered by hypoxia. Copyright © 2016 Elsevier Inc. All rights reserved.

NREL'S Morgan-Smith Honored by Martin Luther King Commission

Science.gov Websites

Morgan-Smith Honored by Martin Luther King Commission For more information contact: Sarah Holmes Barba, 303-275-3023 email: Sarah Barba Golden, Colo., Jan. 9, 2001 - Syl Morgan-Smith, Colorado . 10 at 6 p.m. The event will honor the life and work of King and the eight 2001 awardees. Morgan-Smith

Author! Author! The Gallant Children's Author: Dick King-Smith

ERIC Educational Resources Information Center

Brodie, Carolyn S.

2005-01-01

This column presents a brief biography of Dick King-Smith. Born on March 27, 1922 and raised in Gloucestershire, England, he grew up with animals of all kinds. King-Smith was a farmer for twenty years and then became a school teacher. He was also a soldier during wartime, a traveling salesman, shoe factory worker, and television presenter. He…

Sustainable fisheries in shallow lakes: an independent empirical test of the Chinese mitten crab yield model

NASA Astrophysics Data System (ADS)

Wang, Haijun; Liang, Xiaomin; Wang, Hongzhu

2017-07-01

Next to excessive nutrient loading, intensive aquaculture is one of the major anthropogenic impacts threatening lake ecosystems. In China, particularly in the shallow lakes of mid-lower Changjiang (Yangtze) River, continuous overstocking of the Chinese mitten crab ( Eriocheir sinensis) could deteriorate water quality and exhaust natural resources. A series of crab yield models and a general optimum-stocking rate model have been established, which seek to benefit both crab culture and the environment. In this research, independent investigations were carried out to evaluate the crab yield models and modify the optimum-stocking model. Low percentage errors (average 47%, median 36%) between observed and calculated crab yields were obtained. Specific values were defined for adult crab body mass (135 g/ind.) and recapture rate (18% and 30% in lakes with submerged macrophyte biomass above and below 1 000 g/m2) to modify the optimum-stocking model. Analysis based on the modified optimum-stocking model indicated that the actual stocking rates in most lakes were much higher than the calculated optimum-stocking rates. This implies that, for most lakes, the current stocking rates should be greatly reduced to maintain healthy lake ecosystems.

Juvenile Arthritis

MedlinePlus

... Keep me signed in Passwords are Case Sensitive. Ex. Enter smith as follows: Smith Forgot Username/Password? ... Erythematosus (Juvenile) Takayasu's Arteritis Tendinitis & Bursitis Tumor Necrosis Factor Receptor Associated Periodic Syndrome (Juvenile) Vasculitis Enfermedades y ...

Dermatomyositis (Juvenile)

MedlinePlus

... Keep me signed in Passwords are Case Sensitive. Ex. Enter smith as follows: Smith Forgot Username/Password? ... Erythematosus (Juvenile) Takayasu's Arteritis Tendinitis & Bursitis Tumor Necrosis Factor Receptor Associated Periodic Syndrome (Juvenile) Vasculitis Enfermedades y ...

The origin of the argonium emission discovered in the Crab Nebula

NASA Astrophysics Data System (ADS)

Priestley, Felix; Barlow, Mike; Viti, Serena

2016-06-01

We present a study of the origin of the argonium (ArH+) emission discovered by Herschel in the Crab Nebula (Barlow et al. 2013). The argonium molecule is believed to be formed principally by the reaction of singly ionised argon (Ar+) with molecular hydrogen (H2), and to be destroyed by reactions with H2 and UV photons. For the case of the argonium ground state absorption lines seen by Herschel along several interstellar sightlines (Schilke et al. 2014), those authors argued that the presence of H2 in both the formation and destruction mechanisms means that ArH+ must form in largely atomic interstellar hydrogen clouds containing only trace amounts of H2. However, In the case of the Crab Nebula the observed argonium emission might originate either from transition regions containing both Ar+ and H2, or alternatively from inside the Crab Nebula's H2 knots into which X-ray photons or charged particles from the pulsar wind nebula have penetrated to produce Ar+ and other ions. We report the results of our numerical studies that have used a combination of photoionisation and photodissociation region codes to investigate these alternative scenarios for producing ArH+ in the Crab Nebula.

Pharmacokinetics of cefovecin (Convenia) in white bamboo sharks (Chiloscyllium plagiosum) and Atlantic horseshoe crabs (Limulus polyphemus).

PubMed

Steeil, James C; Schumacher, Juergen; George, Robert H; Bulman, Frank; Baine, Katherine; Cox, Sherry

2014-06-01

Cefovecin was administered to six healthy adult white bamboo sharks (Chiloscyllium plagiosum) and six healthy adult Atlantic horseshoe crabs (Limulus polyphemus) to determine its pharmacokinetics in these species. A single dose of cefovecin at 8 mg/kg was administered subcutaneously in the epaxial region of the bamboo sharks and in the proximal articulation of the lateral leg of the horseshoe crabs. Blood and hemolymph samples were collected at various time points from bamboo sharks and Atlantic horseshoe crabs. High performance liquid chromatography was performed to determine plasma levels of cefovecin. The terminal halflife of cefovecin in Atlantic horseshoe crabs was 37.70 +/- 9.04 hr and in white bamboo sharks was 2.02 +/- 4.62 hr. Cefovecin concentrations were detected for 4 days in white bamboo sharks and for 14 days in Atlantic horseshoe crabs. No adverse effects associated with cefovecin administration were seen in either species.

76 FR 39369 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fishery; Amendment 3

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-06

... crab vessels may not deploy parlor traps/pots in water depths greater than 400 meters (219 fathoms... water deeper than 400 m; prohibit a limited access red crab vessel from harvesting red crab in water shallower than 400 m; and prohibit parlor traps from being deployed at water shallower than 400 m. This...

Juvenile Justice & Youth Violence.

ERIC Educational Resources Information Center

Howell, James C.

Youth violence and the juvenile justice system in the United States are explored. Part 1 takes stock of the situation. The first chapter discusses the origins and evaluation of the juvenile justice system, and the second considers the contributions of the Federal Juvenile Justice and Delinquency Prevention Act to the existing juvenile justice…

77 FR 27030 - North Pacific Fishery Management Council; Notice of Public Meetings

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-08

... program. The Committee will give specific attention to the development of the price formula for golden king crab under the arbitration system. Additional information is posted on the Council Web site: http...

Conceptualizing juvenile prostitution as child maltreatment: findings from the National Juvenile Prostitution Study.

PubMed

Mitchell, Kimberly J; Finkelhor, David; Wolak, Janis

2010-02-01

Two studies were conducted to identify the incidence (Study 1) and characteristics (Study 2) of juvenile prostitution cases known to law enforcement agencies in the United States. Study 1 revealed a national estimate of 1,450 arrests or detentions (95% confidence interval [CI]: 1,287-1,614) in cases involving juvenile prostitution during a 1-year period. In Study 2, exploratory data were collected from a subsample of 138 cases from police records in 2005. The cases are broadly categorized into three main types: (a) third-party exploiters, (b) solo prostitution, and (c) conventional child sexual abuse (CSA) with payment. Cases were classified into three initial categories based on police orientation toward the juvenile: (a) juveniles as victims (53%), (b) juveniles as delinquents (31%), and (c) juvenile as both victims and delinquents (16%). When examining the status of the juveniles by case type, the authors found that all the juveniles in CSA with payment cases were treated as victims, 66% in third-party exploiters cases, and 11% in solo cases. Findings indicate law enforcement responses to juvenile prostitution are influential in determining whether such youth are viewed as victims of commercial sexual exploitation or as delinquents.

Sumara Thompson-King Swearing in Ceremony

NASA Image and Video Library

2014-06-02

Sumara Thompson-King is seen here being sworn in by Robert Lightfoot, Associate Administrator (not pictured) at NASA Headquarters in Washington, DC on June 2, 2014. Thompson-King assumed the role of General Counsel on Sunday, June 1, 2014 after Michael Wholley, former General Counsel, retired. She started her career at NASA in the Office of Chief Counsel at Goddard Space Flight Center in Greenbelt, MD in 1986. In 1991, she became a senior attorney at NASA Headquarters and in 1995 was promoted to the Deputy Associate General Counsel (Contracts) position. She is the first woman and first African American to serve as General Counsel at NASA Headquarters. (Photo Credit: NASA/Aubrey Gemignani)

Sumara Thompson-King Swearing in Ceremony

NASA Image and Video Library

2014-06-02

Sumara Thompson-King is seen here being sworn in by Robert Lightfoot, Associate Administrator (left) at NASA Headquarters in Washington, DC on June 2, 2014. Thompson-King assumed the role of General Counsel on Sunday, June 1, 2014 after Michael Wholley, former General Counsel, retired. She started her career at NASA in the Office of Chief Counsel at Goddard Space Flight Center in Greenbelt, MD in 1986. In 1991, she became a senior attorney at NASA Headquarters and in 1995 was promoted to the Deputy Associate General Counsel (Contracts) position. She is the first woman and first African American to serve as General Counsel at NASA Headquarters. (Photo Credit: NASA/Aubrey Gemignani)

Sumara Thompson-King Swearing in Ceremony

NASA Image and Video Library

2014-06-02

Sumara Thompson-King is seen here after being sworn in by Robert Lightfoot, Associate Administrator (left) at NASA Headquarters in Washington, DC on June 2, 2014. Thompson-King assumed the role of General Counsel on Sunday, June 1, 2014 after Michael Wholley, former General Counsel, retired. She started her career at NASA in the Office of Chief Counsel at Goddard Space Flight Center in Greenbelt, MD in 1986. In 1991, she became a senior attorney at NASA Headquarters and in 1995 was promoted to the Deputy Associate General Counsel (Contracts) position. She is the first woman and first African American to serve as General Counsel at NASA Headquarters. (Photo Credit: NASA/Aubrey Gemignani)

Black Juveniles in the Juvenile Justice System: A Cause for Alarm.

ERIC Educational Resources Information Center

LeFlore, Larry

This report examines the representation of black youth in the juvenile justice system, describes changes in juvenile justice philosophy, and discusses policy implications. Black youth are overrepresented at all stages of the juvenile justice system compared to white youth. Positivist theories explain this overrepresentation as the result of…

Evidence for wing molt and breeding site fidelity in King Eiders

USGS Publications Warehouse

Phillips, Laura M.; Powell, A.N.

2006-01-01

Fidelity of King Eiders (Somateria spectabilis) to breeding and wing molt sites was examined using satellite telemetry data obtained opportunistically when battery life of transmitters provided locations in a second year. Consecutive breeding locations were obtained for eleven female and 23 male King Eiders. All females exhibited breeding site fidelity by returning to sites within 15 km of first year breeding areas on the North Slope of Alaska. Breeding locations of males in a subsequent year were located on average >1000 km from their prior breeding sites and were primarily outside Alaska, on the coasts of Russia and Canada. Second-year wing molt locations were obtained for two female and six male King Eiders. Wing molt sites of males were located 6.2 ?? 3.1 km apart on average in successive years, while female wing molt locations averaged almost 50 km apart. Our results demonstrate site fidelity of female King Eiders to a breeding area on the North Slope of Alaska, document the dispersal of male King Eiders between breeding seasons, and present the first evidence for wing molt site fidelity in males.

76 FR 35772 - Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands Crab...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-20

... landings of GOA pollock from 1996 to 2000 as well as a Bering Sea snow crab landing volume cap of no more... fishermen to expand their fishing operations into other fisheries. Because the Bering Sea snow crab... Bering Sea snow crab quota share (QS) could give them an incentive to increase effort in GOA groundfish...

Effects of horseshoe crab harvest in delaware bay on red knots: Are harvest restrictions working?