Arctic Whale Ecology Study October 2012 Quarterly Report
Through an Inter-Agency agreement (IA) between the National Marine Mammal Laboratory (NMML) and the Bureau of Ocean Energy Management (BOEM), NMML is conducting a dedicated multi-year study to determine relationships between dominant currents passing from the Bering Sea into and through the Chukchi Sea and prey resources delivered to the Barrow Arch area (an area of high bowhead whale and prey concentrations between Wainwright and Smith Bay), and to provide information about the dynamic nature of those relationships relative to whale distribution and habitat utilization in the eastern Chukchi and extreme western Beaufort Seas. This study will also provide important baseline data on the occurrence, distribution and habitat use of large whales in an area that is subject to rapid change in climate and human industrial development. This quarterly report covers the first period of this study between 25 July and 30 September 2012.
The major activity during this period consisted of purchasing equipment, deploying the first set of longterm moorings, and opportunistically tagging a gray whale during the Chukchi Sea Acoustics, Oceanography, and Zooplankton (CHAOZ) cruise on 25 August, 2012. The CHAOZ cruise took place from 8 August through 7 September on the chartered research vessel R/V Aquila. Seventeen scientists, technicians, and observers from eight different laboratories and institutions participated on the CHAOZ cruise.
The western Arctic physical climate is rapidly changing. The summer minimum sea ice extent in 2007 and 2008 covered an area which was 37% less than that of two decades ago. Summer minimum ice extent essentially tied 2007 with lowest ice extent recorded. The speed of these changes was unexpected, as the consensus of the climate research community just a few years ago was that such changes would not be seen for another thirty years. As sea temperature, oceanographic currents, and prey availability are altered by climate change, parallel changes in baleen whale species composition, abundance and distribution are expected (and evidenced already by local knowledge and opportunistic sightings). In addition, the observed northward retreat of the minimum extent of summer sea ice has the potential to create opportunities for the expansion of oil and gas-related exploration and development into previously closed seasons and localities in the Alaskan Arctic. It will also open maritime transportation lanes across the Arctic adding (to a potentially dramatic degree) to the ambient noise in the environment. This combination of increasing anthropogenic impacts, coupled with the steadily increasing abundance and related seasonal range expansion by bowhead (Balaena mysticetus), gray (Eschrichtius robustus), humpback (Megaptera novaeangliae) and fin whales (Balaenoptera physalus), mandates that more complete information on the year-round presence of large whales is needed in the Chukchi Sea planning area. Timing and location of whale migrations may play an important role in assessing where, when or how exploration or access to petroleum reserves may be conducted, to mitigate or minimize the impact on protected species.