BEGIN:VCALENDAR VERSION:2.0 PRODID:-//jEvents 2.0 for Joomla//EN CALSCALE:GREGORIAN METHOD:PUBLISH BEGIN:VEVENT UID:7d832a1e6a425cd985517c4fc6ea74b8 CATEGORIES:Polar Online Events CREATED:20210406T124556 SUMMARY:ARCUS Arctic Research Seminar with Emily Choy LOCATION:Online DESCRIPTION:The Arctic Research Consortium of the U.S. (ARCUS) invites registration for the next Arctic Research Seminar featuring Emily Choy, postdoctoral fellow in the Department of Natural Resource Sciences at McGill University and En vironment and Climate Change Canada. Emily’s presentation, titled Marine Pr edators as Sentinels of Environmental Change in Arctic Ecosystems, will be held via Zoom on Friday, 23 April 2021 at 9:00 a.m. AKDT (1:00 p.m. EDT).\n Seminar Abstract:\nArctic ecosystems are undergoing rapid change, and long- lived top predators are considered sentinels of the impacts of climate chan ge on marine ecosystems. Beaufort Sea beluga whales (Delphinapterus leucas) and thick-billed murres (Uria lomvia) in northern Hudson Bay have experien ced long-term shifts in prey species and declines in inferred growth rates, believed to be the result of environmental changes. In partnership with In uvialuit communities, we examined inter-annual variation and environmental factors affecting prey, body condition, and physiology of Beaufort Sea belu ga whales. The estimated proportional contributions of Arctic cod (Boreogad us saida) to beluga diet decreased from 2011 to 2014, coinciding with an in crease in capelin (Mallotus villosus). Belugas consumed the highest proport ions of capelin and the lowest proportions of cod in 2014. Body condition o f whales was positively correlated with myoglobin, hemoglobin concentration s, and % hematocrit, resulting in lower total body oxygen stores in whales with lower body condition. The relationship between body condition and oxyg en storage capacity may represent a positive feedback mechanism, in which e nvironmental changes resulting in decreased body condition impair foraging ability. To examine the impacts of climate-induced prey shifts on the energ etics of seabirds, heart rate was examined as a proxy for O2 consumption in murres and black-legged kittiwakes (Rissa tridactyla), and were calibrated with GPS-accelerometers to classify behaviours and activity rate. Finally, we examined the effects of Arctic warming on murre physiology. In response to increasing temperatures, murres exhibited limited heat tolerance and lo w ability to dissipate heat, with one of the lowest evaporative cooling eff iciencies recorded in birds. These results highlight the various impacts of climate change on marine predators and their broader implications on Arcti c ecosystems.\nRegistration is required for this event. Instructions for ac cessing the webinar will be sent to registrants prior to the event.\nTo reg ister for the event, go to:\nARCUS Arctic Research Seminar Series webpage ( https://www.arcus.org/research-seminar-series)\n X-ALT-DESC;FMTTYPE=text/html:

The Arctic Research Consortium of the U.S. (ARCUS) invites registration for the next Arctic Research Seminar featuring Emily Choy, postdoctoral fellow in the Department of Natu ral Resource Sciences at McGill University and Environment and Climate Chan ge Canada. Emily’s presentation, titled Marine Predators as Sentine ls of Environmental Change in Arctic Ecosystems, will be held via Zoom on Friday, 23 April 2021 at 9:00 a.m. AKDT (1:00 p.m. EDT).

Seminar Abstract:

Arctic ecosystems are undergoing rapid change, and long-lived top predators are considered sentinels of the impac ts of climate change on marine ecosystems. Beaufort Sea beluga whales (Delp hinapterus leucas) and thick-billed murres (Uria lomvia) in northern Hudson Bay have experienced long-term shifts in prey species and declines in infe rred growth rates, believed to be the result of environmental changes. In p artnership with Inuvialuit communities, we examined inter-annual variation and environmental factors affecting prey, body condition, and physiology of Beaufort Sea beluga whales. The estimated proportional contributions of Ar ctic cod (Boreogadus saida) to beluga diet decreased from 2011 to 2014, coi nciding with an increase in capelin (Mallotus villosus). Belugas consumed t he highest proportions of capelin and the lowest proportions of cod in 2014 . Body condition of whales was positively correlated with myoglobin, hemogl obin concentrations, and % hematocrit, resulting in lower total body oxygen stores in whales with lower body condition. The relationship between body condition and oxygen storage capacity may represent a positive feedback mec hanism, in which environmental changes resulting in decreased body conditio n impair foraging ability. To examine the impacts of climate-induced prey s hifts on the energetics of seabirds, heart rate was examined as a proxy for O2 consumption in murres and black-legged kittiwakes (Rissa tridactyla), a nd were calibrated with GPS-accelerometers to classify behaviours and activ ity rate. Finally, we examined the effects of Arctic warming on murre physi ology. In response to increasing temperatures, murres exhibited limited hea t tolerance and low ability to dissipate heat, with one of the lowest evapo rative cooling efficiencies recorded in birds. These results highlight the various impacts of climate change on marine predators and their broader imp lications on Arctic ecosystems.

Registra tion is required for this event. Instructions for accessing the webinar wil l be sent to registrants prior to the event.

To register for the event, go to:
ARCUS Arctic Resear ch Seminar Series webpage

DTSTAMP:20260420T151319Z DTSTART;TZID=UTC;VALUE=DATE:20210423 DTEND;TZID=UTC;VALUE=DATE:20210424 SEQUENCE:0 TRANSP:OPAQUE END:VEVENT END:VCALENDAR