Bear-ly There: DNA Shows Black Bear Relationships
Black bears in Louisiana and Arkansas have historically dubious pedigrees. Biologists have long debated whether the bears represent genetically distinct sub-species, deserving protection under the Endangered Species Act, or hybrids of Minnesota bears introduced when bear populations plummeted. University of Arkansas biologists have used genetic techniques to examine the genetic distance between the sub-species, and their results may change the way the two states manage their black bear populations.
To determine the genetic relationships between bear populations, biologists Kimberly Smith, Douglas Rhoads and their colleagues examined the DNA of three populations of bears in Arkansas, two in Louisiana and one in Minnesota, examining a total of 82 bears.
The researchers found that the White River Refuge bears and the Louisiana coastal bears demonstrated the most genetic distance from the others, indicating that their populations had been isolated from the others for longer. The genetic markers from the Ouachita, Ozark, inland Louisiana and Minnesota black bears showed that they were more closely related.
The White River Refuge population has bloomed to about 600 bears, and as their numbers have increased, so have their interactions with humans. The Arkansas Game and Fish Commission started a limited hunting season on these bears in 2001, and 70 animals were harvested. If the 600 White River Refuge black bears become lumped in a family with the Louisiana black bear, the increase in population could bump the mammal off the threatened list. However, if the inland Louisiana bears prove to be hybrids of the Minnesota sub-species, then they may not be protected under the Endangered Species Act, which leaves the bears and their habitat vulnerable to exploitation.