Hidden Victims of Border Fence: Black Bears Scientists say barrier hurts their migration By Matt Cantor, Newser User Posted Dec 22, 2011 1:57 PM CST 12 comments Comments The border fence is posing a problem for black bears. (Shutterstock) (Newser) – They're seeing their homeland divided by a border fence—and with very little say in Washington, there's not much they can do about it. The fence along the border of Arizona may pose a threat to ... black bear migration, researchers say. Using pieces of barbed wire to catch fur samples, experts discovered that black bears in Arizona's border area have close relatives in northern Mexico, and the population near the border is far less dense than it is up north, the New York Times reports. The more northern population has a bigger habitat less affected by development. The border, however, is a key area for bears: It's the southern limit for many North American populations and the northern limit for bears south of the border. Now, bear advocates are asking Homeland Security to consider the plight of bears when working on border solutions, and they hope the new research might lead to novel ideas. As for the immigration issue itself, "we’re not weighing into that debate," says a researcher.