An adult bearded seal resting on sea ice in Kotzebue Sound, Alaska. Photo by Mike Cameron.

BEARDED SEALS (Erignathus barbatus) are one of the most important subsistence resources for the native people of coastal northern and western Alaska. They are also a key ecological component of arctic and subarctic marine ecosystems, yet surprisingly little is known of their population structure, abundance, or trends.  A primary reason that bearded seals are less studied than most other seal species is because they are very wary and difficult to approach.

Bearded seals may be negatively impacted by offshore oil and gas development as they are strongly associated with the shallow continental shelf zones that would likely be subject to petroleum exploration and extraction. Our ability to predict the nature and severity of impacts is limited, however, by inadequate knowledge of bearded seal habitat use, foraging ecology, and population size. As inhabitants of the broken pack ice and open water zones, bearded seals are vulnerable to impacts of spilled oil, both from direct exposure and from the indirect effects through the benthic organisms on which they feed. In addition, vocalizations, which are critical to bearded seal mating systems, could also be disrupted by industrial noise

In preparation for a Minerals Management Service study on the environmental impacts of increasing oil and gas development in the Chukchi Sea, the MMS established an interagency agreement in 2007 with researchers from the National Marine Mammal Laboratory’s Polar Ecosystems Program (PEP) which included support to study the seasonal movements and foraging behaviors of adult bearded seals in U.S. waters. As part of that agreement, PEP scientists consulted with other researchers, members of the Alaska Native Ice Seal Committee, and other Alaska Native subsistence hunters in 2008 to develop a method for capturing and tagging adult bearded seals after the molt in June.

The following is a description of the field work of a pilot study conducted in 2009 and a summary of the preliminary study results. The study represents the first capture of adult bearded seals to be instrumented with satellite-linked data recorders in Alaska.

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