Suboptimal movement across the urban landscape can lead to injury or death and, thus, has a high fitness cost. Many cities have developed wildlife corridors that allow animals to move through the urban matrix while reducing their chances of being struck by a vehicle.
But what if impervious surfaces, such as bike paths, can act as artificial corridors? This is exactly what Dr. Chris Schell (who is also a contributor to this blog) sought to investigate in Fort Collins, Colorado. Dr. Schell set up camera traps along an urban to rural gradient with cameras set at least 1km apart. Dr. Schell then examined impervious surface, housing density, vegetation density, the distance of the camera to a river, the distance of the camera to a river, and the density of rivers in the area in relation to the camera trap images. Preliminary results suggest that coyotes are not responding to trails and raccoons are kind of responding to trails. Additional research is needed to understand if other carnivores, such as red foxes and striped skunks, are using the artificial corridors and if the use of trails differs between predators and prey. Moreover, because bike trails are often lit at night for their human occupants, artificial light at night (ALAN) may deter some wildlife from using this landscape feature.
In Los Angeles, California Roshni Katrak-Adefowora is examining the relationship between landscape variables and large carnivores. Katrak-Adefowora notes that Los Angeles is one of only two megacities (the other being Mumbi, India) that has large cats living within the city limits. In addition to pumas, the Los Angeles metropolitan area also has bobcats, foxes, coyotes, deer, and even bears. Using species observations and landscape variables (impervious surface, vegetation, and streams) Katrak-Adefowora sought to determine where are the optimal wildlife corridors? To analyze the data Katrak-Adefowora used circuitscape, which “borrows algorithms from electronic circuit theory to predict connectivity in heterogeneous landscapes.” Research like Katrak-Adefowora’s is essential for wildlife biologists and city planners as urbanization and the movement of wild animals through cities increases.
Featured image “Roadkill” by Brian Leon of Ottawa is licensed under CC BY-ND 2.0
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