February 23, 2006Today there are some 500,000 bison in the
United States, up from just a few hundred about a century ago. Many live
in commercial herds, but only about 400 bison in public herds are
thought to be disease free and genetically pure (most bison today have
some amount of crossbreeding with cows in their ancestral past).
Now conservationists are using a helicopter to round up some of
these 400 and send the animals to the Montana prairie and, hopefully, a