Summary: | Louisiana black bears (Ursus americanus luteolus) exist in 3 isolated populations in Louisiana and are listed as a threatened subspecies under the United States endangered species act. In order to establish a population of black bears in central Louisiana and to promote connectivity among existing populations 11 adult females and 28 cubs were reintroduced to suitable habitat on Lake Ophelia National Wildlife Refuge. We captured and monitored females in the Tensas River Basin (TRB) in northeast Louisiana for use in these reintroduction efforts and to study their ecology. Specifically, I studied the food habits, space use, habitat selection, and denning behavior of female bears in the TRB and reintroduced populations. Within the TRB bears exist in 2 subpopulations (Tensas and Deltic) which inhabit highly variable landscapes. Bears on Tensas inhabit a large (>300 km<sup>2</sup>) contiguous block of bottomland hardwood forest, whereas bears on Deltic inhabit small (<7 km<sup>2</sup>) forest fragments surrounded by a matrix of agricultural fields. Bears in the TRB ate an omnivorous diet dominated by plant foods that shifted to exploit seasonally available foods. Important food items included: herbaceous vegetation, soft mast, corn, acorns, and beetles. Spring home ranges and core areas on Tensas differed between females with and without cubs. Ranges of females on Tensas were larger than those on Deltic, and ranges of reintroduced females were larger than both TRB subpopulations. Habitat selection patterns also differed as females on Tensas selected swamps and regenerating forests at most spatial scales and during most seasons, whereas Deltic females selected upland and lowland forests. Lake Ophelia females selected upland and lowland forests when establishing home ranges, but did not exhibit non-random habitat use within home ranges. In the TRB, parturient females used tree dens more frequently than ground dens, whereas non-parturient used tree and ground dens with similar frequency. Tensas den sites were closer than expected to swamps, water, and regenerating forests, whereas Deltic den sites were closer than expected to upland and lowland forests. I discuss the results in relation to fragmentation, forest management practices, and conservation.
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