The challenges of a small population exposed to multiple anthropogenic stressors and a changing climate: the St. Lawrence Estuary beluga
Until 2012, the St. Lawrence Estuary beluga population was considered stable with about 1100 individuals. An abnormally high number of calves reported dead that year triggered a population status reassessment. This review article summarizes the findings from this reassessment and various studies sub...
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Norwegian Polar Institute
2021
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ftdoajarticles:oai:doaj.org/article:d3aeb4859f844413a4277b185dfd4cdc 2023-05-15T15:41:41+02:00 The challenges of a small population exposed to multiple anthropogenic stressors and a changing climate: the St. Lawrence Estuary beluga Véronique Lesage 2021-09-01T00:00:00Z https://doi.org/10.33265/polar.v40.5523 https://doaj.org/article/d3aeb4859f844413a4277b185dfd4cdc EN eng Norwegian Polar Institute https://polarresearch.net/index.php/polar/article/view/5523/13811 https://doaj.org/toc/0800-0395 https://doaj.org/toc/1751-8369 0800-0395 1751-8369 doi:10.33265/polar.v40.5523 https://doaj.org/article/d3aeb4859f844413a4277b185dfd4cdc Polar Research, Vol 40, Pp 1-18 (2021) delphinapterus leucas climate change population dynamics noise food availability cumulative effects Environmental sciences GE1-350 Oceanography GC1-1581 article 2021 ftdoajarticles https://doi.org/10.33265/polar.v40.5523 2022-12-31T09:12:37Z Until 2012, the St. Lawrence Estuary beluga population was considered stable with about 1100 individuals. An abnormally high number of calves reported dead that year triggered a population status reassessment. This review article summarizes the findings from this reassessment and various studies subsequent to it and provides an updated analysis of carcass recovery rates up to 2019. The 2013 review indicated a decreased incidence of cancer in adults, suggesting positive impacts from the regulation of toxic substances (e.g., PCBs and PAHs). However, the review also revealed that the population initiated a decline of ca. 1% per year in the early 2000s and had reached a size of ca. 900 individuals by 2012. This decline was accompanied by high inter-annual variability in calf survival and pregnancy rates and by more frequent peripartum complications among dead females. The change in population dynamics coincided with a shift in the St. Lawrence ecosystem structure and warmer environmental conditions, suggesting a link through effects on reproductive success and adult female body condition. This was supported by the continued high calf mortality after 2012 and a documented decline of fat reserves in beluga blubber from 1998 to 2016. Other factors, such as the exposure to chronic vessel noise, increasing whale-watching activities, high contaminant levels and episodic harmful algal blooms, may also be contributing to the long-term non-recovery and current decline of the population. The strong natal philopatry and complex social system of the beluga likely increase its vulnerability to extinction risk by limiting dispersal. Article in Journal/Newspaper Beluga Beluga* Delphinapterus leucas Polar Research Directory of Open Access Journals: DOAJ Articles Polar Research 40 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
language |
English |
topic |
delphinapterus leucas climate change population dynamics noise food availability cumulative effects Environmental sciences GE1-350 Oceanography GC1-1581 |
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delphinapterus leucas climate change population dynamics noise food availability cumulative effects Environmental sciences GE1-350 Oceanography GC1-1581 Véronique Lesage The challenges of a small population exposed to multiple anthropogenic stressors and a changing climate: the St. Lawrence Estuary beluga |
topic_facet |
delphinapterus leucas climate change population dynamics noise food availability cumulative effects Environmental sciences GE1-350 Oceanography GC1-1581 |
description |
Until 2012, the St. Lawrence Estuary beluga population was considered stable with about 1100 individuals. An abnormally high number of calves reported dead that year triggered a population status reassessment. This review article summarizes the findings from this reassessment and various studies subsequent to it and provides an updated analysis of carcass recovery rates up to 2019. The 2013 review indicated a decreased incidence of cancer in adults, suggesting positive impacts from the regulation of toxic substances (e.g., PCBs and PAHs). However, the review also revealed that the population initiated a decline of ca. 1% per year in the early 2000s and had reached a size of ca. 900 individuals by 2012. This decline was accompanied by high inter-annual variability in calf survival and pregnancy rates and by more frequent peripartum complications among dead females. The change in population dynamics coincided with a shift in the St. Lawrence ecosystem structure and warmer environmental conditions, suggesting a link through effects on reproductive success and adult female body condition. This was supported by the continued high calf mortality after 2012 and a documented decline of fat reserves in beluga blubber from 1998 to 2016. Other factors, such as the exposure to chronic vessel noise, increasing whale-watching activities, high contaminant levels and episodic harmful algal blooms, may also be contributing to the long-term non-recovery and current decline of the population. The strong natal philopatry and complex social system of the beluga likely increase its vulnerability to extinction risk by limiting dispersal. |
format |
Article in Journal/Newspaper |
author |
Véronique Lesage |
author_facet |
Véronique Lesage |
author_sort |
Véronique Lesage |
title |
The challenges of a small population exposed to multiple anthropogenic stressors and a changing climate: the St. Lawrence Estuary beluga |
title_short |
The challenges of a small population exposed to multiple anthropogenic stressors and a changing climate: the St. Lawrence Estuary beluga |
title_full |
The challenges of a small population exposed to multiple anthropogenic stressors and a changing climate: the St. Lawrence Estuary beluga |
title_fullStr |
The challenges of a small population exposed to multiple anthropogenic stressors and a changing climate: the St. Lawrence Estuary beluga |
title_full_unstemmed |
The challenges of a small population exposed to multiple anthropogenic stressors and a changing climate: the St. Lawrence Estuary beluga |
title_sort |
challenges of a small population exposed to multiple anthropogenic stressors and a changing climate: the st. lawrence estuary beluga |
publisher |
Norwegian Polar Institute |
publishDate |
2021 |
url |
https://doi.org/10.33265/polar.v40.5523 https://doaj.org/article/d3aeb4859f844413a4277b185dfd4cdc |
genre |
Beluga Beluga* Delphinapterus leucas Polar Research |
genre_facet |
Beluga Beluga* Delphinapterus leucas Polar Research |
op_source |
Polar Research, Vol 40, Pp 1-18 (2021) |
op_relation |
https://polarresearch.net/index.php/polar/article/view/5523/13811 https://doaj.org/toc/0800-0395 https://doaj.org/toc/1751-8369 0800-0395 1751-8369 doi:10.33265/polar.v40.5523 https://doaj.org/article/d3aeb4859f844413a4277b185dfd4cdc |
op_doi |
https://doi.org/10.33265/polar.v40.5523 |
container_title |
Polar Research |
container_volume |
40 |
_version_ |
1766374576223158272 |