Master of Science (MS)
Forestry, Wildlife, and Fisheries
Animal movements are related to many parameters of interest such as the search for food and other life requisites. Several measures, including home range, have been used to quantify and describe animal movement. However, fine-scaled movements of mammals have received less attention even though they are more directly related to energy expended for locating resources and provide information on how a home range is used. I tracked radiotagged female black bears (Ursus americanus) from two geographically separate populations in the Atchafalaya River Basin in south central Louisiana: the Coastal population at the southern extent and the Inland population at the northern extent. During tracking sessions, 2 technicians and myself measured azimuths from telemetry stations to radio-collared bears and test transmitters at 5-minute intervals for an average of 5.1 hours. I used these data to estimate 39 travel paths for 15 individual bears tracked from 1 to 7 times. Randomization tests indicated that telemetry precision was sufficient to detect fine-scaled bear movements. Movement path turning angles, measured relative to the previous direction of travel, and net displacement of individuals through time indicated that bears concentrated their movements (net displacement <72m) approximately 50% of the time, suggesting that they were utilizing a concentrated or patchily distributed resource. I failed to detect any differences in measures of fractal dimension, a scaling relation providing an index of path tortuosity or “wiggliness”, among bears in different reproductive conditions, study areas, or seasons. Bear, hour relative to sunset, reproductive condition, and season influenced the fall movement rates of bears. The effects of reproductive condition and time of day were not consistent across bears, and the effect of time of day was not consistent across reproductive conditions. Movement extent, or area traversed during an average tracking session, was similar between study areas, but Coastal females used a larger percentage of their home range. These data suggest life requisites are more compactly distributed in the Coastal area. Despite the difference in the distribution of bear resources between Coastal and Inland suggested by these data, I failed to detect any habitat preferences or avoidance of anthropogenic features such as roads and agricultural fields in either study area using movement path location data.
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Hightower, Dwayne Allen, "Fine-scaled movements and habitat use of black bears in south central Louisiana" (2003). LSU Master's Theses. 1638.
Richard M. Pace, III