Impacts of food web structure and feeding behavior on mercury exposure in Greenland Sharks (Somniosus microcephalus)
Benthic and pelagic food web components in Cumberland Sound, Canada were explored as sources of total mercury (THg) to Greenland Sharks (Somniosus microcephalus) via both bottom-up food web transfer and top-down shark feeding behavior. Log10THg increased significantly with δ15N and trophic position...
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ftunivwindsor:oai:scholar.uwindsor.ca:glierpub-1360 2023-06-11T04:09:48+02:00 Impacts of food web structure and feeding behavior on mercury exposure in Greenland Sharks (Somniosus microcephalus) McMeans, Bailey C. Arts, Michael T. Fisk, Aaron T. 2015-03-05T08:00:00Z https://scholar.uwindsor.ca/glierpub/358 https://doi.org/10.1016/j.scitotenv.2014.01.128 unknown Scholarship at UWindsor https://scholar.uwindsor.ca/glierpub/358 doi:10.1016/j.scitotenv.2014.01.128 https://doi.org/10.1016/j.scitotenv.2014.01.128 Great Lakes Institute for Environmental Research Publications Fatty acid Food web Greenland Shark Mercury biomagnification Stable isotope Trophic transfer text 2015 ftunivwindsor https://doi.org/10.1016/j.scitotenv.2014.01.128 2023-05-06T19:10:50Z Benthic and pelagic food web components in Cumberland Sound, Canada were explored as sources of total mercury (THg) to Greenland Sharks (Somniosus microcephalus) via both bottom-up food web transfer and top-down shark feeding behavior. Log10THg increased significantly with δ15N and trophic position from invertebrates (0.01±0.01μg·g-1 [113±1ng·g-1] dw in copepods) to Greenland Sharks (3.54±1.02μg·g-1). The slope of the log10THg vs. δ15N linear regression was higher for pelagic compared to benthic food web components (excluding Greenland Sharks, which could not be assigned to either food web), which resulted from THg concentrations being higher at the base of the benthic food web (i.e., in benthic than pelagic primary consumers). However, feeding habitat is unlikely to consistently influence shark THg exposure in Cumberland Sound because THg concentrations did not consistently differ between benthic and pelagic shark prey. Further, size, gender and feeding behavior (inferred from stable isotopes and fatty acids) were unable to significantly explain THg variability among individual Greenland Sharks. Possible reasons for this result include: 1) individual sharks feeding as generalists, 2) high overlap in THg among shark prey, and 3) differences in turnover time between ecological tracers and THg. This first assessment of Greenland Shark THg within an Arctic food web revealed high concentrations consistent with biomagnification, but low ability to explain intra-specific THg variability. Our findings of high THg levels and consumption of multiple prey types, however, suggest that Greenland Sharks acquire THg through a variety of trophic pathways and are a significant contributor to the total biotic THg pool in northern seas. Text Arctic Cumberland Sound Greenland Somniosus microcephalus Copepods University of Windsor, Ontario: Scholarship at UWindsor Arctic Canada Greenland Cumberland Sound ENVELOPE(-66.014,-66.014,65.334,65.334) Science of The Total Environment 509-510 216 225 |
institution |
Open Polar |
collection |
University of Windsor, Ontario: Scholarship at UWindsor |
op_collection_id |
ftunivwindsor |
language |
unknown |
topic |
Fatty acid Food web Greenland Shark Mercury biomagnification Stable isotope Trophic transfer |
spellingShingle |
Fatty acid Food web Greenland Shark Mercury biomagnification Stable isotope Trophic transfer McMeans, Bailey C. Arts, Michael T. Fisk, Aaron T. Impacts of food web structure and feeding behavior on mercury exposure in Greenland Sharks (Somniosus microcephalus) |
topic_facet |
Fatty acid Food web Greenland Shark Mercury biomagnification Stable isotope Trophic transfer |
description |
Benthic and pelagic food web components in Cumberland Sound, Canada were explored as sources of total mercury (THg) to Greenland Sharks (Somniosus microcephalus) via both bottom-up food web transfer and top-down shark feeding behavior. Log10THg increased significantly with δ15N and trophic position from invertebrates (0.01±0.01μg·g-1 [113±1ng·g-1] dw in copepods) to Greenland Sharks (3.54±1.02μg·g-1). The slope of the log10THg vs. δ15N linear regression was higher for pelagic compared to benthic food web components (excluding Greenland Sharks, which could not be assigned to either food web), which resulted from THg concentrations being higher at the base of the benthic food web (i.e., in benthic than pelagic primary consumers). However, feeding habitat is unlikely to consistently influence shark THg exposure in Cumberland Sound because THg concentrations did not consistently differ between benthic and pelagic shark prey. Further, size, gender and feeding behavior (inferred from stable isotopes and fatty acids) were unable to significantly explain THg variability among individual Greenland Sharks. Possible reasons for this result include: 1) individual sharks feeding as generalists, 2) high overlap in THg among shark prey, and 3) differences in turnover time between ecological tracers and THg. This first assessment of Greenland Shark THg within an Arctic food web revealed high concentrations consistent with biomagnification, but low ability to explain intra-specific THg variability. Our findings of high THg levels and consumption of multiple prey types, however, suggest that Greenland Sharks acquire THg through a variety of trophic pathways and are a significant contributor to the total biotic THg pool in northern seas. |
format |
Text |
author |
McMeans, Bailey C. Arts, Michael T. Fisk, Aaron T. |
author_facet |
McMeans, Bailey C. Arts, Michael T. Fisk, Aaron T. |
author_sort |
McMeans, Bailey C. |
title |
Impacts of food web structure and feeding behavior on mercury exposure in Greenland Sharks (Somniosus microcephalus) |
title_short |
Impacts of food web structure and feeding behavior on mercury exposure in Greenland Sharks (Somniosus microcephalus) |
title_full |
Impacts of food web structure and feeding behavior on mercury exposure in Greenland Sharks (Somniosus microcephalus) |
title_fullStr |
Impacts of food web structure and feeding behavior on mercury exposure in Greenland Sharks (Somniosus microcephalus) |
title_full_unstemmed |
Impacts of food web structure and feeding behavior on mercury exposure in Greenland Sharks (Somniosus microcephalus) |
title_sort |
impacts of food web structure and feeding behavior on mercury exposure in greenland sharks (somniosus microcephalus) |
publisher |
Scholarship at UWindsor |
publishDate |
2015 |
url |
https://scholar.uwindsor.ca/glierpub/358 https://doi.org/10.1016/j.scitotenv.2014.01.128 |
long_lat |
ENVELOPE(-66.014,-66.014,65.334,65.334) |
geographic |
Arctic Canada Greenland Cumberland Sound |
geographic_facet |
Arctic Canada Greenland Cumberland Sound |
genre |
Arctic Cumberland Sound Greenland Somniosus microcephalus Copepods |
genre_facet |
Arctic Cumberland Sound Greenland Somniosus microcephalus Copepods |
op_source |
Great Lakes Institute for Environmental Research Publications |
op_relation |
https://scholar.uwindsor.ca/glierpub/358 doi:10.1016/j.scitotenv.2014.01.128 https://doi.org/10.1016/j.scitotenv.2014.01.128 |
op_doi |
https://doi.org/10.1016/j.scitotenv.2014.01.128 |
container_title |
Science of The Total Environment |
container_volume |
509-510 |
container_start_page |
216 |
op_container_end_page |
225 |
_version_ |
1768383802236731392 |