Using geographic information systems to examine red wolf home range and habitat use in the Great Smoky Mountains National Park

Abstract

A Geographic Information System (GIS) analysis was conducted to determine home range and habitat use patterns of the reintroduced red wolf (Canis rufus) in the Great Smoky Mountains National Park (GSMNP). To facilitate this GIS analysis, the original telemetry data was first converted from obsolete file formats into a contemporary database. When spatial movement patterns of animals are analyzed with regard to habitat characteristics, habitat use patterns may be revealed. In order to ascertain gender-based home range and core area size differences, home range and core areas were determined for 16 of 31 red wolf data sets (9 male, 7 female). A fixed kernel analysis with least squares cross validation was used to determine home range (95%) and core areas (50%) from location estimate datasets with outliers removed (5%). I determined the mean value for the 95% home range of adult male wolves (n = 4) to be 18.44 km2 +/ - 5.29 (mean +/- SE), and the mean value of adult female wolves (n = 3) to be 18.98 km2 +/- 5.53. I compared the dependent variables of home rang e (95%) and core area (500/4) size of7 adult wolves (3 females, 4 males) and found no significant gender-based difference in male and female home range and core area size using a Studentized I-test (t (5) = 0.078, p \u3e 0.05, two-tailed). The GIS based use-availability analysis examined location estimates with respect to three habitat attributes: aspect, slope, and land cover. Individual home range (95%) estimates were used to independently define the available habitat of individual red wolf datasets. The independent variable, individual wolves, and three dependent variables, aspect, slope, and landcover were tested using Chi square tests for goodness of fit (a = 0.05). Individual red wolf datasets displaying habitat use significantly different from random were further examined and assigned individual habitat use values ( +, 0, -). These values were established by comparing observed and expected habitat use values for each habitat classification within each habitat attribute for each individual wolf dataset. Individual red wolf habitat use values were then examined in an attempt to detect overall habitat use trends among the non-random datasets within each of the three habitat attributes. In the absence of comparative red wolf home range and habitat use data, the results of three eastern coyote studies were used to make comparisons. I used eastern coyote studies from Vermont, south central Georgia, and the GSMNP. Red wolf home range estimates were similar but slightly larger than home range estimates for Vermont and Georgia coyotes. Habitat use patterns of male and female red wolves in the GSMNP were similar and that habitat usage suggested a habitat preference. The null hypothesis that red wolf utilization of aspect is proportional to its availability within their 95% home range was rejected for 4 of 16 wolves (3 females, 1 male). There were no trends in aspect use detected. The null hypothesis that red wolf utilization of slope is proportional to its availability within their 95% home range was rejected for 10 of 16 wolves (6 females, 4 males). There was no difference detected between male and female red wolf utilization of habitat in respect to slope. Male and female red wolves utilized habitat with slopes less than 20% greater than expected and utilized habitats with greater than 20% slope less than expected. The null hypothesis that red wolf utilization of land cover is proportional to its availability within their 95% home range was rejected for 8 of 16 wolves (5 females, 3 males). Red wolf habitat use was greater than expected for the land cover classifications of pasture and deciduous forest. Red wolf habitat use was less than expected for the land cover classifications of evergreen forest and mixed forest. Home range comparisons between the two species indicated the red wolf had a slightly larger home range size than eastern coyotes. A larger red wolf home range may be a function of the difference in body size and diet of the two species. The coyote is a highly adaptive generalist, while the red wolf may be more of a specialist. Habitat use patterns of the red wolf were also similar to GSMNP, Georgia, and Vermont coyotes in that all used deciduous forest greater than statistically expected. Habitat use patterns varied between canids occurring in the GSMNP and those occurring in Vermont and Georgia for pastures or open areas. Red wolves and GSMNP coyotes utilized pastures diurnally , while coyotes in Vermont and Georgia were active in open areas and field nocturnally. Temporal differences in habitat use inside and outside the GSMNP may be directly related to hunting pressure. The GSMNP provides canids protection from the hunting pressures which may come to bear on coyotes in Vermont and Georgia

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