Effects of edge on predation by mammals.

Predation of artificial ground nests was studied. The rate of predation was evaluated with respect to distance from an edge and ground cover density. Raccoons were shown to be the major nest predator by smoked cards, but other predators are a possibility. The edges used were a two track road and a river. Along the two track, the distance from the edge had no effect on predation: 52% of predated nests were near, and 48% were far from the edge. Along the river, nests farther from the river were predated more than those near the river: 11% of predated nests were near, and 89% were far from the edge. More overall predation occurred at the road site: 72% of nests along the two track and 45% of nests along the river were predated. More predation occurred at nests with denser ground cover. The mean density measurement is 2.7m at predated nests, and 2.3m at not predated nests.http://deepblue.lib.umich.edu/bitstream/2027.42/54665/1/3105.pdfDescription of 3105.pdf : Access restricted to on-site users at the U-M Biological Station