The Louisiana black bear was listed as threatened within its historic range (defined as southern Mississippi, Louisiana, and east Texas) under the Endangered Species Act on January 7, 1992 (57 FR 588), due to extensive habitat loss and modification, as well as human-related mortality. The Louisiana black bear's threatened status warrants protection under sections 7 and 9 of the Endangered Species Act. The State of Louisiana has increased fines for illegal killing of bears. Black bears are featured as priority species for protection and management on the Tensas and Atchafalaya River National Wildlife Refuges, state-owned wildlife management areas, and on certain privately-owned tracts. The Louisiana black bear was designated the official state mammal of Louisiana in 1992.
Currently, Louisiana supports 3 core bear populations; the Tensas River Basin population in the north, the upper Atchafalaya River Basin population in central LA, and the coastal population in the southern Atchafalaya River Basin. However, black bears particularly dispersing males, can be found throughout Louisiana.
Bear population estimates are an essential component of sound black bear management. Since 2006, LDWF and the University of Tennessee have been working together to develop black bear population estimates for each of the 3 subpopulations in Louisiana.
The hair snare technique was used to develop the initial population estimates and continues to be used to monitor populations over time. The hair snare technique involves construction of a small barbed wire enclosure or corral with bait hung in the center. When bears enter the enclosure to get the bait, hair from their coat is caught on the barbed wire. The hair caught on the barbs is collected weekly by technicians and DNA analysis is conducted on the hair. The DNA analysis is used to identify individual bears and create a minimum population estimate. Hair snares are distributed in a grid pattern across the core of each subpopulation’s range with the snares being about 1 mile apart. Hair snares are run annually during July and August.
Population estimates from hair snares for the 3 subpopulations of Louisiana black bear are:
Tensas subpopulation – Based on data collected during 2006-08, there were approximately 300 bears in the 100,000 acre area that was sampled during that time period. This represents a population density of 1.7 bears per square mile, which is a very high density. This population estimate is a minimum number for the Tensas population because even though the core of the population was sampled there are undoubtedly bears living outside of the sample area.
Upper Atchafalaya subpopulation – Based on data collected during 2007-09, there were approximately 56 bears in the 66,000 acre area that was sampled during that time period. This represents a population density 0.46 bear per square mile. This population estimate is a minimum number for the Upper Atchafalaya population because even though the core of the population was sampled there are undoubtedly bears living outside of the sample area.
Lower Atchafalaya subpopulation – Data are currently being collected and analyzed.
Hair Snare Technique
Using DNA from hair left on barbed wire enclosures, individual bears can be identified and population estimates are produced by using mark-recapture techniques. An advantage of the hair snares is that bears do not have to be captured to acquire samples and "mark" the animals.
Bear hair collected through use of hair snare