Gray whale distribution relative to benthic invertebrate biomass and abundance: Northeastern Chukchi Sea 2009–2012

• Published in: Deep-sea research. Part II, Topical studies in oceanography Topical studies in oceanography, 2017-10, Vol.144, p.156-174
• Main Authors: Brower, Amelia A., Ferguson, Megan C., Schonberg, Susan V., Jewett, Stephen C., Clarke, Janet T.
• Format: Article
• Language: English
• Subjects: Aerial survey; Alaska; Amphipods; Benthic foraging; Benthic-dominated ecosystem; Climate change; Eschrichtius robustus; Pelagic-dominated ecosystem; Sentinel
• ISSN: 0967-0645; 1879-0100
• DOI: 10.1016/j.dsr2.2016.12.007

The shallow continental shelf waters of the Bering and Chukchi seas are the northernmost foraging grounds of North Pacific gray whales (Eschrichtius robustus). Benthic amphipods are considered the primary prey of gray whales in these waters, although no comprehensive quantitative analysis has been performed to support this assumption. Gray whale relative abundance, distribution, and behavior in the northeastern Chukchi Sea (69°–72°N, 155–169°W) were documented during aerial surveys in June-October 2009–2012. Concurrently, vessel-based benthic infaunal sampling was conducted in the area in July-August 2009–10, September 2011, and August 2012. Gray whales were seen in the study area each month that surveys were conducted, with the majority of whales feeding. Statistical analyses confirm that the highest densities of feeding gray whales were associated with high benthic amphipod abundance, primarily within 70km of shore from Point Barrow to Icy Cape, in water