Using Inundation Modeling and Remote Sensing Data to Study Hydrodynamic and Environmental Impacts on the Survival of Cook Inlet’s Beluga Whales

The population of the endangered Cook Inlet Beluga Whales (CIBW) in Alaska has been in decline over the past decades and no convincing explanation has been offered so far for this trend. Therefore, the aim of this project was to continue the analysis of satellite-tracked beluga whale movements (Hobbs et al., 2005; Ezer et al., 2008) and study how environmental parameters such as inlet morphology, tidal currents, temperatures, river flow, ice coverage, etc. may impact the beluga's habitat. Beluga tracking data from ~20 whales in 1999-2003 were analyzed as well as data on beluga stranding event reported in 1999-2010. Environmental data include local observation, hydrodynamic model results (Oey et al., 2007), remote sensing imagery (Ezer and Liu, 2009, 2010), and some regional climatic data. Preliminary results show how the seasonal movement of the CIBW within the inlet is controlled not only by temperature and ice coverage, but also largely by the seasonal flow pattern of various rivers. This suggests that the availability of salmon and other fish in river mouths control the beluga's behavior. The annual counted numbers of beluga whales in CI, as well as the number of reported stranding events, show interannual variations which resemble the Pacific Decadal Oscillation index. However, the way that large-scale climatic variations may impact the beluga population needs further research. This short-term NOAA supported project allows us to start a longer study of CIBW under the support of the Kenai Peninsula Borough. The new interdisciplinary project will include additional experts in GIS/remote sensing and in fisheries ecology.