| The Blackland Prairie of Texas is one of the most heavily altered and threatened ecoregions in North America. A large part of the current threats to the ecoregion are related to rapid urban growth in cities within the Blackland Prairie. Major threats are related to conversion natural and semi-natural land to urban and suburban land, and increased resource demands from the growing urban population. To quantify these changes, I generated landcover maps using unsupervised classification techniques for the years 1984, 1993, 2004, and 2009 in a portion of the central Blackland Prairie centered around Navarro County, Texas and used post-classification comparison to determine the change in landcover. The largest changes in landcover occurred due to the creation of Richland Chambers Reservoir in 1987, and the subsequent flooding of mostly bottomland forest (a loss of 11,858.4ha of water from 1985-1993). This change occurred because of increased demand for water by the population of the Dallas-Fort Worth-Arlington Metropolitan Study Area. Other changes that occurred in the study area included increases in cropland (26,590.14ha from 1985-2009), grass (25,368ha from 1985-2009), and developed (4,877.55ha from 1985-2009) landcover types. Increases in crop and grass landcover types suggest agricultural intensification occurring within the study area, while an increase in developed landcover indicates an increase in urbanization in a mostly rural county.;Since changes in landcover have been demonstrated to affect wildlife in other areas, I used motion-sensing camera traps to survey the predator community in the area. I identified species occurring and developed occupancy models using variables that describe a number of landscape features that may be important to those species. Detections were dominated by a few common species, which included coyotes (ψ4=0.7778 winter, ψ=0.6667 summer), bobcats (ψ=0.8889 winter, ψ=0.7778 summer), raccoons (ψ=1 winter, ψ=0.9091 summer), striped skunks (ψ=0.9167 winter, ψ=0.8182 summer), and opossums (ψ=0.9231 winter, ψ=0.9231 summer). Uncommon species detected included river otters (ψ=0.4000 winter, ψ=0.2000 summer), gray foxes (ψ=0.2308 winter), and one spotted skunk (ψ=0.0833 summer). Results indicate that changes in landscape features will most likely affect mesopredators in the area. Some species will likely increase in abundance and distribution while others will decrease in abundance and distribution as a result of changes.;I also estimated species richness using nonparametric richness estimators that use incidence (presence/absence) data. I detected 9 mesopredator species (bobcat, coyote, opossum, river otter, raccoon, striped skunk, domestic dog, and domestic cat, gray fox, and eastern spotted skunk) in the study area. Considering all study sites at once resulted in species richness estimates of 9-10 species, suggesting that most predators were sampled. When study sites were split into eastern and western groups based on habitat gradients within the study area, slightly different estimates were generated. For the western part of the study area, estimates suggest 9-10 species are present, while in the eastern part of the study area, estimates suggest 6-8 species are present.;Results suggest that mesopredator richness is declining compared to historical levels. Large contiguous prairie habitats need to be protected and/or restored to conserve rare prairie communities and the mesopredators they support. |
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