Bears - Sounds Wild
Glacier Bay bears

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Glacier Bay Bears

A coastal brown bear is beach combing in Glacier Bay, flipping over rocks and small boulders and gobbling up the fish and invertebrates she uncovers. Glacier Bay is a land still emerging from the ice age - the entire bay was filled with ice just 250 years ago and opened relatively recently. Bears, and a few some other animals, were isolated in small refuges of unglaciated habitat.

Park service biologist Tania Lewis was curious about the biological history of the brown bears of Glacier Bay. By sampling DNA in the fur of more than 100 brown bears throughout the Glacier Bay area, she discovered three distinct populations of animals: bears that moved in and colonized Glacier Bay from the Chilkat region around Haines to the northeast, bears that moved in from the Yakutat Forelands to the northwest, and bears that are unique just to Glacier Bay.

The bears unique to the Bay are a remnant population, the population that was isolated in refugia during the ice age. Today the three genetic groups overlap in northern Glacier Bay, but the mix is low, indicating recent immigration.

Lewis says the Glacier Bay brown bears are smaller than their cousins, bold but not aggressive. Because the land is new, they rely heavily on intertidal areas for food, which is why they so often can be found on the beaches and shorelines.