The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform
Phillip S. Levin - One of the best experts on this subject based on the ideXlab platform.
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Movement Patterns and Distributional Shifts of Dungeness Crab (Metacarcinus magister) and English Sole (Parophrys vetulus) During Seasonal Hypoxia
Estuaries and Coasts, 2014Co-Authors: Halley E. Froehlich, Timothy E. Essington, Anne H. Beaudreau, Phillip S. LevinAbstract:Hypoxia (dissolved oxygen
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Movement Patterns and Distributional Shifts of Dungeness Crab (Metacarcinus magister) and English Sole (Parophrys vetulus) During Seasonal Hypoxia
Estuaries and Coasts, 2013Co-Authors: Halley E. Froehlich, Timothy E. Essington, Anne H. Beaudreau, Phillip S. LevinAbstract:Hypoxia (dissolved oxygen < 2 mg L–1) has emerged as a worldwide threat to coastal and estuarine ecosystems. Beyond direct mortality, secondary ecological impacts caused by hypoxia-driven distributional shifts may be equally important. From July–November 2009 and June–September 2010, we quantified the movement patterns of Dungeness crab (Metacarcinus magister) and English sole (Parophrys vetulus) in Hood Canal, Washington USA, a seasonally hypoxic estuary. Although highly mobile (mean cumulative distance ± SD = 11.0 ± 25.6 km, N = 60), there was little evidence of either species exhibiting large-scale directional movement out of the hypoxic region. However, Dungeness crab showed significant shifts towards shallower waters and elevation in activity in the hypoxic region, potentially increasing their vulnerability to crabbing and other indirect ecological consequences. Our findings suggest hypoxia could have a more localized impact on the mobile fauna in Hood Canal. However, more detailed information concerning the local-scale oxygen dynamics and responses of these species, such as English sole vertical movement, is essential for grasping the population and community level effects of hypoxia.
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From mountains to sound: modelling the sensitivity of Dungeness crab and Pacific oyster to land–sea interactions in Hood Canal, WA
ICES Journal of Marine Science, 2013Co-Authors: J. E. Toft, Phillip S. Levin, J. L. Burke, M. P. Carey, C. K. Kim, M. Marsik, K. K. Arkema, A. D. Guerry, David A. Sutherland, T. J. MinelloAbstract:Abstract Many diagnoses of declining marine species and habitats along US coasts point to upland and freshwater sources of imperilment. Yet, little work has examined how and whether activities on land affect marine resources. Similarly, the impacts of climate change on coastal systems are among the most certain; yet, few studies have explored how alternative management and climate scenarios will affect the delivery of diverse benefits to people from coasts. We estimated how Dungeness crab (Metacarcinus magister) and Pacific oyster (Crassostrea gigas) harvest in Hood Canal, WA, may change given predictions of land uses and effects of climate change. These two marine species are critical components of local commercial and recreational fisheries and thus represent key “ecosystem service” endpoints. We found that Dungeness crab harvest responds strongly to effects of climate change, as mediated by increased ocean temperature, whereas Pacific oyster harvest is more responsive to projected change in land-use/land-cover due to increased nutrient loading to the marine system. These changes vary spatially throughout Hood Canal. These results can be used as a heuristic framework to help decision-makers, planners, and other stakeholders in the region as they work to target conservation and restoration activities and plan for future growth in a changing climate.
Lynne S. Bell - One of the best experts on this subject based on the ideXlab platform.
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Comparison of Faunal Scavenging of Submerged Carrion in Two Seasons at a Depth of 170 m, in the Strait of Georgia, British Columbia.
Insects, 2017Co-Authors: Gail S. Anderson, Lynne S. BellAbstract:The taphonomy of carcasses submerged in the ocean is little understood, yet it is extremely important ecologically and forensically. The objectives of this study were to determine the fate of pig carcasses as human proxies in the Strait of Georgia at 170 m in spring and fall. Using Ocean Networks Canada’s Victoria Experimental Network Underseas (VENUS) observatory, two carcasses per season were placed under a cabled platform hosting a webcam and instruments measuring water chemistry. Two minutes of video were recorded every 15 min. In spring, Lyssianassidae amphipods and Pandalus platyceros were immediately attracted and fed on the carcasses, the amphipods removed the bulk of the soft tissue from the inside whilst the shrimp shredded the skin and tissue. The carcasses were skeletonized on Days 8 and 10. In fall, Metacarcinus magister was the major scavenger, removing most of the soft tissue from one carcass. Amphipods did not arrive in large numbers until Day 15, when they skeletonized the scavenged carcass by Day 22 and the less scavenged carcass by Day 24. Amphipods remained for some days after skeletonization. This skeletonization was very different from previous experiments at different depths and habitats. Such data are very valuable for predicting preservation, planning recoveries, and managing family expectations.
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Deep Coastal Marine Taphonomy: Investigation into Carcass Decomposition in the Saanich Inlet, British Columbia Using a Baited Camera
2016Co-Authors: Gail S. Anderson, Lynne S. BellAbstract:Decomposition and faunal colonization of a carcass in the terrestrial environment has been well studied, but knowledge of decomposition in the marine environment is based almost entirely on anecdotal reports. Three pig carcasses were deployed in Saanich Inlet, BC, over 3 years utilizing Ocean Network Canada’s VENUS observatory. Each carcass was deployed in late summer/early fall at 99 m under a remotely controlled camera and observed several times a day. Dissolved oxygen, temperature, salinity, density and pressure were continuously measured. Carcass 1 was immediately colonized by Munida quadrispina, Pandalus platyceros and Metacarcinus magister, rapidly scavenged then dragged from view by Day 22. Artifacts specific to each of the crustaceans ’ feeding patterns were observed. Carcass 2 was scavenged in a similar fashion. Exposed tissue became covered by Orchomenella obtusa (Family Lysianassidae) which removed all the internal tissues rapidly. Carcass 3 attracted only a few M. quadrispina, remaining intact, developing a thick filamentous sulphur bacterial mat, until Day 92, when it was skeletonized by crustacea. The major difference between the deployments was dissolved oxygen levels. The first two carcasses were placed when oxygen levels were tolerable, becoming more anoxic. This allowed larger crustacea to feed. However, Carcass 3 was deployed when the water was already extremely anoxic, which prevented larger crustacea from accessing the carcass. The smaller M. quadrispina were unable to break the skin alone. The larger crustacea returned when the Inlet was re-oxygenated in spring. Oxygen levels, therefore, drive the biota in this area, although most crustacea endured stressful levels of oxygen to access the carcasses for much of the time. These data will be valuable in forensi
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Deep Coastal Marine Taphonomy: Investigation into Carcass Decomposition in the Saanich Inlet, British Columbia Using a Baited Camera
2016Co-Authors: Gail S. Anderson, Lynne S. BellAbstract:Decomposition and faunal colonization of a carcass in the terrestrial environment has been well studied, but knowledge of decomposition in the marine environment is based almost entirely on anecdotal reports. Three pig carcasses were deployed in Saanich Inlet, BC, over 3 years utilizing Ocean Network Canada’s VENUS observatory. Each carcass was deployed in late summer/early fall at 99 m under a remotely controlled camera and observed several times a day. Dissolved oxygen, temperature, salinity, density and pressure were continuously measured. Carcass 1 was immediately colonized by Munida quadrispina, Pandalus platyceros and Metacarcinus magister, rapidly scavenged then dragged from view by Day 22. Artifacts specific to each of the crustaceans ’ feeding patterns were observed. Carcass 2 was scavenged in a similar fashion. Exposed tissue became covered by Orchomenella obtusa (Family Lysianassidae) which removed all the internal tissues rapidly. Carcass 3 attracted only a few M. quadrispina, remaining intact, developing a thick filamentous sulphur bacterial mat, until Day 92, when it was skeletonized by crustacea. The major difference between the deployments was dissolved oxygen levels. The first two carcasses were placed when oxygen levels were tolerable, becoming more anoxic. This allowed larger crustacea to feed. However, Carcass 3 was deployed when the water was already extremely anoxic, which prevented larger crustacea from accessing the carcass. The smaller M. quadrispina were unable to break the skin alone. The larger crustacea returned when the Inlet was re-oxygenated in spring. Oxygen levels, therefore, drive the biota in this area, although most crustace
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Deep coastal marine taphonomy: investigation into carcass decomposition in the Saanich Inlet, British Columbia using a baited camera.
PloS one, 2014Co-Authors: Gail S. Anderson, Lynne S. BellAbstract:Decomposition and faunal colonization of a carcass in the terrestrial environment has been well studied, but knowledge of decomposition in the marine environment is based almost entirely on anecdotal reports. Three pig carcasses were deployed in Saanich Inlet, BC, over 3 years utilizing Ocean Network Canada’s VENUS observatory. Each carcass was deployed in late summer/early fall at 99 m under a remotely controlled camera and observed several times a day. Dissolved oxygen, temperature, salinity, density and pressure were continuously measured. Carcass 1 was immediately colonized by Munida quadrispina, Pandalus platyceros and Metacarcinus magister, rapidly scavenged then dragged from view by Day 22. Artifacts specific to each of the crustaceans’ feeding patterns were observed. Carcass 2 was scavenged in a similar fashion. Exposed tissue became covered by Orchomenella obtusa (Family Lysianassidae) which removed all the internal tissues rapidly. Carcass 3 attracted only a few M. quadrispina, remaining intact, developing a thick filamentous sulphur bacterial mat, until Day 92, when it was skeletonized by crustacea. The major difference between the deployments was dissolved oxygen levels. The first two carcasses were placed when oxygen levels were tolerable, becoming more anoxic. This allowed larger crustacea to feed. However, Carcass 3 was deployed when the water was already extremely anoxic, which prevented larger crustacea from accessing the carcass. The smaller M. quadrispina were unable to break the skin alone. The larger crustacea returned when the Inlet was re-oxygenated in spring. Oxygen levels, therefore, drive the biota in this area, although most crustacea endured stressful levels of oxygen to access the carcasses for much of the time. These data will be valuable in forensic investigations involving submerged bodies, indicating types of water conditions to which the body has been exposed, identifying post-mortem artifacts and providing realistic expectations for recovery divers and families of the deceased.
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Progression of carcass scavenging and degradation for Carcass 1, 2006.
2014Co-Authors: Gail S. Anderson, Lynne S. BellAbstract:A. Carcass first placed, Pandalus platyceros Brandt (three spot shrimp) (P.p.) and Metacarcinus magister Dana (Dungeness crab) (M.m.) immediately attracted; B. Shark wound extremely attractive to all fauna; C. Intestines exposed, many M.m. and Munida quadrispina Benedict (squat lobster) (M.q.) feeding; D. Spinal column exposed, organs removed; E. Carcass dragged from weights and away from camera, much of carcass skeletonized, lasers indicate 10 cm; F. Carcass turned 180° by fauna, head area mostly intact with some grazing marks from M.q. (Ocean Network Canada’s VENUS observatory).
Timothy E. Essington - One of the best experts on this subject based on the ideXlab platform.
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when does hypoxia affect management performance of a fishery a management strategy evaluation of dungeness crab Metacarcinus magister fisheries in hood canal washington usa
Canadian Journal of Fisheries and Aquatic Sciences, 2017Co-Authors: Halley E. Froehlich, Timothy E. Essington, Sean P McdonaldAbstract:Management strategies for fisheries typically do not account for environmental stressors, such as hypoxia (dissolved oxygen < 2 mg·L−1). Hypoxia can lead to shoaling of organisms into normoxic habi...
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Extending Vulnerability Assessment to Include Life Stages Considerations.
PloS one, 2016Co-Authors: Emma E. Hodgson, Timothy E. Essington, Isaac C. KaplanAbstract:Species are experiencing a suite of novel stressors from anthropogenic activities that have impacts at multiple scales. Vulnerability assessment is one tool to evaluate the likely impacts that these stressors pose to species so that high-vulnerability cases can be identified and prioritized for monitoring, protection, or mitigation. Commonly used semi-quantitative methods lack a framework to explicitly account for differences in exposure to stressors and organism responses across life stages. Here we propose a modification to commonly used spatial vulnerability assessment methods that includes such an approach, using ocean acidification in the California Current as an illustrative case study. Life stage considerations were included by assessing vulnerability of each life stage to ocean acidification and were used to estimate population vulnerability in two ways. We set population vulnerability equal to: (1) the maximum stage vulnerability and (2) a weighted mean across all stages, with weights calculated using Lefkovitch matrix models. Vulnerability was found to vary across life stages for the six species explored in this case study: two krill-Euphausia pacifica and Thysanoessa spinifera, pteropod-Limacina helicina, pink shrimp-Pandalus jordani, Dungeness crab-Metacarcinus magister and Pacific hake-Merluccius productus. The maximum vulnerability estimates ranged from larval to subadult and adult stages with no consistent stage having maximum vulnerability across species. Similarly, integrated vulnerability metrics varied greatly across species. A comparison showed that some species had vulnerabilities that were similar between the two metrics, while other species' vulnerabilities varied substantially between the two metrics. These differences primarily resulted from cases where the most vulnerable stage had a low relative weight. We compare these methods and explore circumstances where each method may be appropriate.
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Movement Patterns and Distributional Shifts of Dungeness Crab (Metacarcinus magister) and English Sole (Parophrys vetulus) During Seasonal Hypoxia
Estuaries and Coasts, 2014Co-Authors: Halley E. Froehlich, Timothy E. Essington, Anne H. Beaudreau, Phillip S. LevinAbstract:Hypoxia (dissolved oxygen
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Movement Patterns and Distributional Shifts of Dungeness Crab (Metacarcinus magister) and English Sole (Parophrys vetulus) During Seasonal Hypoxia
Estuaries and Coasts, 2013Co-Authors: Halley E. Froehlich, Timothy E. Essington, Anne H. Beaudreau, Phillip S. LevinAbstract:Hypoxia (dissolved oxygen < 2 mg L–1) has emerged as a worldwide threat to coastal and estuarine ecosystems. Beyond direct mortality, secondary ecological impacts caused by hypoxia-driven distributional shifts may be equally important. From July–November 2009 and June–September 2010, we quantified the movement patterns of Dungeness crab (Metacarcinus magister) and English sole (Parophrys vetulus) in Hood Canal, Washington USA, a seasonally hypoxic estuary. Although highly mobile (mean cumulative distance ± SD = 11.0 ± 25.6 km, N = 60), there was little evidence of either species exhibiting large-scale directional movement out of the hypoxic region. However, Dungeness crab showed significant shifts towards shallower waters and elevation in activity in the hypoxic region, potentially increasing their vulnerability to crabbing and other indirect ecological consequences. Our findings suggest hypoxia could have a more localized impact on the mobile fauna in Hood Canal. However, more detailed information concerning the local-scale oxygen dynamics and responses of these species, such as English sole vertical movement, is essential for grasping the population and community level effects of hypoxia.
Halley E. Froehlich - One of the best experts on this subject based on the ideXlab platform.
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when does hypoxia affect management performance of a fishery a management strategy evaluation of dungeness crab Metacarcinus magister fisheries in hood canal washington usa
Canadian Journal of Fisheries and Aquatic Sciences, 2017Co-Authors: Halley E. Froehlich, Timothy E. Essington, Sean P McdonaldAbstract:Management strategies for fisheries typically do not account for environmental stressors, such as hypoxia (dissolved oxygen < 2 mg·L−1). Hypoxia can lead to shoaling of organisms into normoxic habi...
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Movement Patterns and Distributional Shifts of Dungeness Crab (Metacarcinus magister) and English Sole (Parophrys vetulus) During Seasonal Hypoxia
Estuaries and Coasts, 2014Co-Authors: Halley E. Froehlich, Timothy E. Essington, Anne H. Beaudreau, Phillip S. LevinAbstract:Hypoxia (dissolved oxygen
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Movement Patterns and Distributional Shifts of Dungeness Crab (Metacarcinus magister) and English Sole (Parophrys vetulus) During Seasonal Hypoxia
Estuaries and Coasts, 2013Co-Authors: Halley E. Froehlich, Timothy E. Essington, Anne H. Beaudreau, Phillip S. LevinAbstract:Hypoxia (dissolved oxygen < 2 mg L–1) has emerged as a worldwide threat to coastal and estuarine ecosystems. Beyond direct mortality, secondary ecological impacts caused by hypoxia-driven distributional shifts may be equally important. From July–November 2009 and June–September 2010, we quantified the movement patterns of Dungeness crab (Metacarcinus magister) and English sole (Parophrys vetulus) in Hood Canal, Washington USA, a seasonally hypoxic estuary. Although highly mobile (mean cumulative distance ± SD = 11.0 ± 25.6 km, N = 60), there was little evidence of either species exhibiting large-scale directional movement out of the hypoxic region. However, Dungeness crab showed significant shifts towards shallower waters and elevation in activity in the hypoxic region, potentially increasing their vulnerability to crabbing and other indirect ecological consequences. Our findings suggest hypoxia could have a more localized impact on the mobile fauna in Hood Canal. However, more detailed information concerning the local-scale oxygen dynamics and responses of these species, such as English sole vertical movement, is essential for grasping the population and community level effects of hypoxia.
Gail S. Anderson - One of the best experts on this subject based on the ideXlab platform.
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Comparison of Faunal Scavenging of Submerged Carrion in Two Seasons at a Depth of 170 m, in the Strait of Georgia, British Columbia.
Insects, 2017Co-Authors: Gail S. Anderson, Lynne S. BellAbstract:The taphonomy of carcasses submerged in the ocean is little understood, yet it is extremely important ecologically and forensically. The objectives of this study were to determine the fate of pig carcasses as human proxies in the Strait of Georgia at 170 m in spring and fall. Using Ocean Networks Canada’s Victoria Experimental Network Underseas (VENUS) observatory, two carcasses per season were placed under a cabled platform hosting a webcam and instruments measuring water chemistry. Two minutes of video were recorded every 15 min. In spring, Lyssianassidae amphipods and Pandalus platyceros were immediately attracted and fed on the carcasses, the amphipods removed the bulk of the soft tissue from the inside whilst the shrimp shredded the skin and tissue. The carcasses were skeletonized on Days 8 and 10. In fall, Metacarcinus magister was the major scavenger, removing most of the soft tissue from one carcass. Amphipods did not arrive in large numbers until Day 15, when they skeletonized the scavenged carcass by Day 22 and the less scavenged carcass by Day 24. Amphipods remained for some days after skeletonization. This skeletonization was very different from previous experiments at different depths and habitats. Such data are very valuable for predicting preservation, planning recoveries, and managing family expectations.
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Deep Coastal Marine Taphonomy: Investigation into Carcass Decomposition in the Saanich Inlet, British Columbia Using a Baited Camera
2016Co-Authors: Gail S. Anderson, Lynne S. BellAbstract:Decomposition and faunal colonization of a carcass in the terrestrial environment has been well studied, but knowledge of decomposition in the marine environment is based almost entirely on anecdotal reports. Three pig carcasses were deployed in Saanich Inlet, BC, over 3 years utilizing Ocean Network Canada’s VENUS observatory. Each carcass was deployed in late summer/early fall at 99 m under a remotely controlled camera and observed several times a day. Dissolved oxygen, temperature, salinity, density and pressure were continuously measured. Carcass 1 was immediately colonized by Munida quadrispina, Pandalus platyceros and Metacarcinus magister, rapidly scavenged then dragged from view by Day 22. Artifacts specific to each of the crustaceans ’ feeding patterns were observed. Carcass 2 was scavenged in a similar fashion. Exposed tissue became covered by Orchomenella obtusa (Family Lysianassidae) which removed all the internal tissues rapidly. Carcass 3 attracted only a few M. quadrispina, remaining intact, developing a thick filamentous sulphur bacterial mat, until Day 92, when it was skeletonized by crustacea. The major difference between the deployments was dissolved oxygen levels. The first two carcasses were placed when oxygen levels were tolerable, becoming more anoxic. This allowed larger crustacea to feed. However, Carcass 3 was deployed when the water was already extremely anoxic, which prevented larger crustacea from accessing the carcass. The smaller M. quadrispina were unable to break the skin alone. The larger crustacea returned when the Inlet was re-oxygenated in spring. Oxygen levels, therefore, drive the biota in this area, although most crustacea endured stressful levels of oxygen to access the carcasses for much of the time. These data will be valuable in forensi
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Deep Coastal Marine Taphonomy: Investigation into Carcass Decomposition in the Saanich Inlet, British Columbia Using a Baited Camera
2016Co-Authors: Gail S. Anderson, Lynne S. BellAbstract:Decomposition and faunal colonization of a carcass in the terrestrial environment has been well studied, but knowledge of decomposition in the marine environment is based almost entirely on anecdotal reports. Three pig carcasses were deployed in Saanich Inlet, BC, over 3 years utilizing Ocean Network Canada’s VENUS observatory. Each carcass was deployed in late summer/early fall at 99 m under a remotely controlled camera and observed several times a day. Dissolved oxygen, temperature, salinity, density and pressure were continuously measured. Carcass 1 was immediately colonized by Munida quadrispina, Pandalus platyceros and Metacarcinus magister, rapidly scavenged then dragged from view by Day 22. Artifacts specific to each of the crustaceans ’ feeding patterns were observed. Carcass 2 was scavenged in a similar fashion. Exposed tissue became covered by Orchomenella obtusa (Family Lysianassidae) which removed all the internal tissues rapidly. Carcass 3 attracted only a few M. quadrispina, remaining intact, developing a thick filamentous sulphur bacterial mat, until Day 92, when it was skeletonized by crustacea. The major difference between the deployments was dissolved oxygen levels. The first two carcasses were placed when oxygen levels were tolerable, becoming more anoxic. This allowed larger crustacea to feed. However, Carcass 3 was deployed when the water was already extremely anoxic, which prevented larger crustacea from accessing the carcass. The smaller M. quadrispina were unable to break the skin alone. The larger crustacea returned when the Inlet was re-oxygenated in spring. Oxygen levels, therefore, drive the biota in this area, although most crustace
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Deep coastal marine taphonomy: investigation into carcass decomposition in the Saanich Inlet, British Columbia using a baited camera.
PloS one, 2014Co-Authors: Gail S. Anderson, Lynne S. BellAbstract:Decomposition and faunal colonization of a carcass in the terrestrial environment has been well studied, but knowledge of decomposition in the marine environment is based almost entirely on anecdotal reports. Three pig carcasses were deployed in Saanich Inlet, BC, over 3 years utilizing Ocean Network Canada’s VENUS observatory. Each carcass was deployed in late summer/early fall at 99 m under a remotely controlled camera and observed several times a day. Dissolved oxygen, temperature, salinity, density and pressure were continuously measured. Carcass 1 was immediately colonized by Munida quadrispina, Pandalus platyceros and Metacarcinus magister, rapidly scavenged then dragged from view by Day 22. Artifacts specific to each of the crustaceans’ feeding patterns were observed. Carcass 2 was scavenged in a similar fashion. Exposed tissue became covered by Orchomenella obtusa (Family Lysianassidae) which removed all the internal tissues rapidly. Carcass 3 attracted only a few M. quadrispina, remaining intact, developing a thick filamentous sulphur bacterial mat, until Day 92, when it was skeletonized by crustacea. The major difference between the deployments was dissolved oxygen levels. The first two carcasses were placed when oxygen levels were tolerable, becoming more anoxic. This allowed larger crustacea to feed. However, Carcass 3 was deployed when the water was already extremely anoxic, which prevented larger crustacea from accessing the carcass. The smaller M. quadrispina were unable to break the skin alone. The larger crustacea returned when the Inlet was re-oxygenated in spring. Oxygen levels, therefore, drive the biota in this area, although most crustacea endured stressful levels of oxygen to access the carcasses for much of the time. These data will be valuable in forensic investigations involving submerged bodies, indicating types of water conditions to which the body has been exposed, identifying post-mortem artifacts and providing realistic expectations for recovery divers and families of the deceased.
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Progression of carcass scavenging and degradation for Carcass 1, 2006.
2014Co-Authors: Gail S. Anderson, Lynne S. BellAbstract:A. Carcass first placed, Pandalus platyceros Brandt (three spot shrimp) (P.p.) and Metacarcinus magister Dana (Dungeness crab) (M.m.) immediately attracted; B. Shark wound extremely attractive to all fauna; C. Intestines exposed, many M.m. and Munida quadrispina Benedict (squat lobster) (M.q.) feeding; D. Spinal column exposed, organs removed; E. Carcass dragged from weights and away from camera, much of carcass skeletonized, lasers indicate 10 cm; F. Carcass turned 180° by fauna, head area mostly intact with some grazing marks from M.q. (Ocean Network Canada’s VENUS observatory).