Monitoring Bowhead Whale Occurrence and Habitat in the Bering Sea Using Passive Acoustics

Mark Baumgartner, Biology

Arctic Research Initiative
2009 Funded Project

Abstract

The Arctic is experiencing rapid shifts in climate, yielding changes in ice and trophic ecosystem dynamics. In particular, the Bering Sea ecosystem is closely tied to sea ice dynamics, making it disproportionately susceptible to decreased environmental stability.  Arctic marine mammal species utilize the Bering Sea as seasonal habitat, carrying out important life history events related to the cryosphere.  Consequently, increasingly ice free periods and intensifying anthropogenic activities in the Arctic will challenge the adaptability of these species; therefore, there is an urgent need to characterize current habitat use and identify critical habitat for future protection. Monitoring of marine mammals wintering in the Bering Sea is virtually impossible using traditional visual survey methods.

We propose to integrate hydrophone packages into extant oceanographic moorings to collect physical and biological oceanographic data (1) in the Bering Strait (a migratory gateway) and (2) southwest of St. Lawrence Island (a winter refuge) for one year.  These coupled acoustic and oceanographic data will allow us to document seasonal occurrence, resolve migration timing, and help to characterize critical habitat (e.g., bowhead whale breeding grounds).  Documentation of the context and extent of bowhead whale occurrence in specific regions like the Bering Strait and near St. Lawrence Island polynya will inform (1) dynamic ecosystem models seeking to understand habitat utilization patterns and (2) agencies charges with managing Arctic marine mammals impacted by global climate change.