Trends in Stranding and By-Catch Rates of Gray and Harbor Seals along the Northeastern Coast of the United States: Evidence of Divergence in the Abundance of Two Sympatric Phocid Species?
Harbor seals and gray seals are sympatric phocid pinnipeds found in coastal waters of the temperate and sub-Arctic North Atlantic. In the Northwest Atlantic, both species were depleted through a combination of subsistence hunts and government supported bounties, and are now re-occupying substantial...
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ftdoajarticles:oai:doaj.org/article:8746f929d1aa4776ad0ac60930050046 2023-05-15T15:13:32+02:00 Trends in Stranding and By-Catch Rates of Gray and Harbor Seals along the Northeastern Coast of the United States: Evidence of Divergence in the Abundance of Two Sympatric Phocid Species? David W Johnston Jaime Frungillo Ainsley Smith Katie Moore Brian Sharp Janelle Schuh Andrew J Read 2015-01-01T00:00:00Z https://doi.org/10.1371/journal.pone.0131660 https://doaj.org/article/8746f929d1aa4776ad0ac60930050046 EN eng Public Library of Science (PLoS) http://europepmc.org/articles/PMC4511798?pdf=render https://doaj.org/toc/1932-6203 1932-6203 doi:10.1371/journal.pone.0131660 https://doaj.org/article/8746f929d1aa4776ad0ac60930050046 PLoS ONE, Vol 10, Iss 7, p e0131660 (2015) Medicine R Science Q article 2015 ftdoajarticles https://doi.org/10.1371/journal.pone.0131660 2022-12-31T02:51:27Z Harbor seals and gray seals are sympatric phocid pinnipeds found in coastal waters of the temperate and sub-Arctic North Atlantic. In the Northwest Atlantic, both species were depleted through a combination of subsistence hunts and government supported bounties, and are now re-occupying substantial portions of their original ranges. While both species appear to have recovered during the past 2 decades, our understanding of their population dynamics in US waters is incomplete. Here we describe trends in stranding and bycatch rates of harbor and gray seals in the North East United States (NEUS) over the past 16 years through an exploratory curve-fitting exercise and structural break-point analysis. Variability in gray seal strandings in Southern New England and bycatch in the Northeast Sink Gillnet Fishery were best described by fitting positive exponential and linear models, and exhibited rates of increase as high as 22%. In contrast, neither linear nor exponential models fit the oscillation of harbor seal strandings and bycatch over the study period. However, a breakpoint Chow test revealed that harbor seal strandings in the Cape Cod, Massachusetts region and harbor seal bycatch in the Northeast Sink Gillnet Fishery increased in the 1990s and then started declining in the early to mid-2000s. Our analysis indicates that ongoing variation in natural and anthropogenic mortality rates of harbor and gray seals in the NEUS is not synchronous, and likely represents diverging trends in abundance of these species as they assume new roles in the marine ecosystems of the region. Article in Journal/Newspaper Arctic harbor seal North Atlantic Northwest Atlantic Directory of Open Access Journals: DOAJ Articles Arctic PLOS ONE 10 7 e0131660 |
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English |
topic |
Medicine R Science Q |
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Medicine R Science Q David W Johnston Jaime Frungillo Ainsley Smith Katie Moore Brian Sharp Janelle Schuh Andrew J Read Trends in Stranding and By-Catch Rates of Gray and Harbor Seals along the Northeastern Coast of the United States: Evidence of Divergence in the Abundance of Two Sympatric Phocid Species? |
topic_facet |
Medicine R Science Q |
description |
Harbor seals and gray seals are sympatric phocid pinnipeds found in coastal waters of the temperate and sub-Arctic North Atlantic. In the Northwest Atlantic, both species were depleted through a combination of subsistence hunts and government supported bounties, and are now re-occupying substantial portions of their original ranges. While both species appear to have recovered during the past 2 decades, our understanding of their population dynamics in US waters is incomplete. Here we describe trends in stranding and bycatch rates of harbor and gray seals in the North East United States (NEUS) over the past 16 years through an exploratory curve-fitting exercise and structural break-point analysis. Variability in gray seal strandings in Southern New England and bycatch in the Northeast Sink Gillnet Fishery were best described by fitting positive exponential and linear models, and exhibited rates of increase as high as 22%. In contrast, neither linear nor exponential models fit the oscillation of harbor seal strandings and bycatch over the study period. However, a breakpoint Chow test revealed that harbor seal strandings in the Cape Cod, Massachusetts region and harbor seal bycatch in the Northeast Sink Gillnet Fishery increased in the 1990s and then started declining in the early to mid-2000s. Our analysis indicates that ongoing variation in natural and anthropogenic mortality rates of harbor and gray seals in the NEUS is not synchronous, and likely represents diverging trends in abundance of these species as they assume new roles in the marine ecosystems of the region. |
format |
Article in Journal/Newspaper |
author |
David W Johnston Jaime Frungillo Ainsley Smith Katie Moore Brian Sharp Janelle Schuh Andrew J Read |
author_facet |
David W Johnston Jaime Frungillo Ainsley Smith Katie Moore Brian Sharp Janelle Schuh Andrew J Read |
author_sort |
David W Johnston |
title |
Trends in Stranding and By-Catch Rates of Gray and Harbor Seals along the Northeastern Coast of the United States: Evidence of Divergence in the Abundance of Two Sympatric Phocid Species? |
title_short |
Trends in Stranding and By-Catch Rates of Gray and Harbor Seals along the Northeastern Coast of the United States: Evidence of Divergence in the Abundance of Two Sympatric Phocid Species? |
title_full |
Trends in Stranding and By-Catch Rates of Gray and Harbor Seals along the Northeastern Coast of the United States: Evidence of Divergence in the Abundance of Two Sympatric Phocid Species? |
title_fullStr |
Trends in Stranding and By-Catch Rates of Gray and Harbor Seals along the Northeastern Coast of the United States: Evidence of Divergence in the Abundance of Two Sympatric Phocid Species? |
title_full_unstemmed |
Trends in Stranding and By-Catch Rates of Gray and Harbor Seals along the Northeastern Coast of the United States: Evidence of Divergence in the Abundance of Two Sympatric Phocid Species? |
title_sort |
trends in stranding and by-catch rates of gray and harbor seals along the northeastern coast of the united states: evidence of divergence in the abundance of two sympatric phocid species? |
publisher |
Public Library of Science (PLoS) |
publishDate |
2015 |
url |
https://doi.org/10.1371/journal.pone.0131660 https://doaj.org/article/8746f929d1aa4776ad0ac60930050046 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic harbor seal North Atlantic Northwest Atlantic |
genre_facet |
Arctic harbor seal North Atlantic Northwest Atlantic |
op_source |
PLoS ONE, Vol 10, Iss 7, p e0131660 (2015) |
op_relation |
http://europepmc.org/articles/PMC4511798?pdf=render https://doaj.org/toc/1932-6203 1932-6203 doi:10.1371/journal.pone.0131660 https://doaj.org/article/8746f929d1aa4776ad0ac60930050046 |
op_doi |
https://doi.org/10.1371/journal.pone.0131660 |
container_title |
PLOS ONE |
container_volume |
10 |
container_issue |
7 |
container_start_page |
e0131660 |
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