Climate Change and Baleen Whale Trophic Cascades in Greenland

• Main Authors: Laidre, Kristin L., Heide-Joergensen, Mads P.
• Other Authors: WASHINGTON UNIV SEATTLE POLAR SCIENCE CENTER
• Format: Text
• Language: English
• Published: 2010
• Subjects: Biology; *WHALES; ECOSYSTEMS; SEA ICE; ICE BREAKUP; GREENLAND; FOOD CHAINS; CLIMATE; ARCTIC REGIONS; Arctic; Greenland; baleen whale; Climate change; Disko Bay; Phytoplankton; Sea ice; Zooplankton
• Online Access: http://www.dtic.mil/docs/citations/ADA539212; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA539212

The primary goal of this study is to examine and contrast the foraging strategies of two baleen whale species in West Greenland. We use a multidisciplinary approach by combining observations of movements, foraging ecology and phenology collected by satellite and archival telemetry with intensive and localized in situ sampling of ocean conditions and prey availability. These baseline trophic relationships are quantified using spatial movement and bioenergetic models. OBJECTIVES We are focusing on two species in Disko Bay, West Greenland and asking the following questions: 1) ?What is the spatial and temporal overlap between bowhead whales, phytoplankton, and zooplankton after the spring sea ice breakup in April and May??, and 2) ?What is the spatial and temporal overlap between humpback whales and capelin in June and July, and 3) on what space and time scales do these two large whales overlap??. Answering these questions will enable us to determine the spatial, temporal, and ecological overlap between these two top predators in West Greenland. Fluxes of organisms across ecosystem boundaries have major consequences for community dynamics and predation can create strong effects throughout food webs. This is one of the few Arctic studies conducted on the multi-species trophic coupling between whales and their prey. The simplicity of the food chains in West Greenland offer unique opportunities to gain insight into predator-prey dynamics also relevant to more complex ecosystems.