scholarly journals Legacy contaminants in the Eastern Beaufort Sea beluga whales (Delphinapterus leucas): Are temporal trends reflecting regulations?

2018 ◽  
Author(s):  
Marie Nöel ◽  
Lisa L. Loseto ◽  
Gary Stern
Keyword(s):  
Temporal Trends ◽  
Beaufort Sea ◽  
Delphinapterus Leucas ◽  
Beluga Whales

Variation in the diet of beluga whales in response to changes in prey availability: insights on changes in the Beaufort Sea ecosystem

2020 ◽  
Vol 647 ◽  
pp. 195-210 ◽  
Author(s):  
ES Choy ◽  
C Giraldo ◽  
B Rosenberg ◽  
JD Roth ◽  
AD Ehrman ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Prey Availability ◽  
Beaufort Sea ◽  
Delphinapterus Leucas ◽  
Fatty Acid Signature ◽  
Arctic Cod ◽  
Beluga Whales ◽  
Highly Sensitive ◽  
Condition Indices

The eastern Beaufort Sea (EBS) beluga whale Delphinapterus leucas population has experienced a 20 yr decline in inferred growth rates of individuals, which is hypothesized to have resulted from changes in prey availability. We used fatty acid signatures and stable isotope ratios to reconstruct the proportional contributions of 14 prey species to the diets of 178 beluga whales from 2011 to 2014. Prey estimates using quantitative fatty acid signature analysis suggest that EBS beluga whales primarily consume Arctic cod Boreogadus saida, a species highly sensitive to climate change. Prey estimates varied with year and sex and size class of the whales, with large males consuming the highest proportions of Arctic cod, and females consuming the highest proportions of capelin Mallotus villosus. Estimated proportional contributions of Arctic cod to beluga diet decreased from 2011 to 2014, coinciding with an increase in capelin. Belugas consumed the highest proportions of capelin and the lowest proportions of cod in 2014, the same year in which body condition indices were lowest in the whales. We hypothesize that changing conditions in the Beaufort Sea ecosystem may result in a decreased consumption of Arctic cod by belugas and increased consumption of capelin, which may result in a decline in condition. This may predominately affect females and juveniles since they consume the highest proportions of capelin; however, long-term monitoring is needed for confirmation. Understanding inter-annual variation in prey, and the longer-term nutritional implications of shifting from an Arctic cod- to a capelin-dominated diet should be a priority for monitoring EBS predators.

Spatial and Temporal Trends of Perfluorinated Compounds in Beluga Whales (Delphinapterus leucas) from Alaska

2011 ◽  
Vol 45 (19) ◽  
pp. 8129-8136 ◽  
Author(s):  
Jessica L. Reiner ◽  
Steven G. O’Connell ◽  
Amanda J. Moors ◽  
John R. Kucklick ◽  
Paul R. Becker ◽  
...  
Keyword(s):  
Temporal Trends ◽  
Perfluorinated Compounds ◽  
Delphinapterus Leucas ◽  
Beluga Whales ◽  
Spatial And Temporal Trends

scholarly journals Microplastics in beluga whales (Delphinapterus leucas) from the Eastern Beaufort Sea

2020 ◽  
Vol 150 ◽  
pp. 110723 ◽  
Author(s):  
R.C. Moore ◽  
L. Loseto ◽  
M. Noel ◽  
A. Etemadifar ◽  
J.D. Brewster ◽  
...  
Keyword(s):  
Beaufort Sea ◽  
Delphinapterus Leucas ◽  
Beluga Whales

scholarly journals Predation of archival tagged Dolly Varden, Salvelinus malma, reveals predator avoidance behaviour and tracks feeding events by presumed beluga whale, Delphinapterus leucas, in the Beaufort Sea

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Colin P. Gallagher ◽  
Luke Storrie ◽  
Michael B. Courtney ◽  
Kimberly L. Howland ◽  
Ellen V. Lea ◽  
...  
Keyword(s):  
Predator Avoidance ◽  
Beaufort Sea ◽  
Avoidance Behaviour ◽  
Delphinapterus Leucas ◽  
Feeding Frequency ◽  
Dolly Varden ◽  
Salvelinus Malma ◽  
Beluga Whales ◽  
Predation Event ◽  
Stomach Temperature

Abstract Background We report compelling evidence suggesting a predation event of a pop-up satellite archival tagged anadromous Dolly Varden (Salvelinus malma) by a marine mammal during summer in the Beaufort Sea based on abrupt changes in temperature and vertical movements. This observation provides insight on predator avoidance behaviour by Dolly Varden and the predator’s feeding frequency while the tag was ingested. Based on published distribution and ecology information, we presumed the predator was a beluga whale (Delphinapterus leucas). Supplemental satellite telemetry data from previously tagged Dolly Varden and beluga whales were used to determine the extent of spatial and vertical overlap between species in the area where predation occurred. Results Prior to the predation event, depths and temperatures occupied by the tagged Dolly Varden averaged 1.1 m and 3.1 °C, respectively. On July 7, 2020, depths remained shallow apart from a sudden dive to 12.5 m (16:45 UTC) followed by a precipitous increase in temperature from 4.4 to 27.1 °C (16:52 UTC) suggesting predation by an endotherm. Subsequent readings indicated the endotherm had a resting stomach temperature of 36.1 °C. Including the predation event, eight separate feeding events were inferred during the 20-h period the tag was ingested (before presumed regurgitation) based on subsequent declines in stomach temperatures (mean decline to 31.1 °C) that took an average of 24.1 min to return to resting temperature. The predator occupied mainly shallow depths (mean = 2.3 m), overlapping with tagged belugas that spent 76.9% of their time occupying waters ≤ 2.5 m when frequenting the area occupied by tagged Dolly Varden in the Canadian Beaufort Sea in July. Back-calculation based on tag drift and mean displacement by tagged belugas indicated the predation likely occurred west of the Mackenzie Delta. Conclusion Our findings provide new information on both anti-predator behaviour by, and marine predators of, Dolly Varden in the Beaufort Sea. We provide the first estimate of feeding frequency and stomach temperature recovery in a presumed wild beluga, and evidence for shallow foraging behaviour by belugas. Elucidating the likely predator and exploring the extent of overlap between Dolly Varden and beluga whales contributes towards knowledge on the trophic interactions in the Beaufort Sea.

Spatial and temporal trends of persistent organic pollutants and mercury in beluga whales (Delphinapterus leucas) from Alaska

2013 ◽  
Vol 449 ◽  
pp. 285-294 ◽  
Author(s):  
Jennifer Hoguet ◽  
Jennifer M. Keller ◽  
Jessica L. Reiner ◽  
John R. Kucklick ◽  
Colleen E. Bryan ◽  
...  
Keyword(s):  
Organic Pollutants ◽  
Persistent Organic Pollutants ◽  
Temporal Trends ◽  
Delphinapterus Leucas ◽  
Beluga Whales ◽  
Spatial And Temporal Trends
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