| Zusammenfassung: | State and federal recovery plans mandate that priority areas for future population expansion be identified within the historical range of the Louisiana black bear (Ursus americanus luteolus). Despite the presence of potentially suitable habitat in east Texas and expanding populations in adjacent states, quantitative estimates of regional habitat suitability do not exist. We developed a regional extent habitat suitability index (HSI) model in a geographic information system (GIS) to evaluate year-round habitat requirements for black bears in the 43,530-km2 south black bear recovery zone in southeastern Texas. We measured hard and soft mast production, understory vegetation density, and tree den availability at 516 survey points in 38 habitat classes (82% of the total area in the south recovery zone). We developed geospatial models for summer food availability; fall food availability, diversity, and productivity; protection cover, tree den availability, distance to roads, and human development zones and calculated HSI scores per pixel in a continuous dataset. Habitat suitability scores ranged from 0.00 to 0.76 throughout southeastern Texas. Highly (<1%) and moderately (16%) suitable habitat existed in the region, although most area (84%) was classified as marginal or unsuitable habitat. We identified 4 recovery units comprising >20,700 ha (mean HSI = 0.5) capable of sustaining viable black bear populations. These units ranged from 62,844 ha to 124,808 ha in size and suitable habitat pixels within units ranged from 0.58 to 0.60 in mean HSI scores. Recovery unit scores were comparable to those previously reported for occupied bear range in the southeastern United States and acreages of suitable habitat exceeded those estimated to support existing Louisiana black bear populations.
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