The Foods of Fur Animals of the Patuxent Research Refuge, Maryland

The food-habits materials that form the basis of this report were collected incidentally in connection with two fur animal investigaticns at the Patuxent Research Refuge. One of these was a three-year (1943-1946) study to determine the fur productivity of a 1000-acre tract of submarginal land on the Refuge (Uhler and Llewellyn, 1952), and the other, a project on the biology of fur-animal populations, was begun by Llewellyn in 1947 and is still in progress. THE AREA The Patuxent Research Refuge of the U. S. Fish and Wildlife Service is a 2650-acre area devoted to wildlife research. It is located in the Patuxent River Watershed in Prince Georges and Anne Arundel counties, Maryland, midway between Baltimore and Washington. The section of the Refuge used for these investigations consists mostly of wooded bottomland of the Patuxent River. This flood plain is separated by low bluffs from irregular areas of nearly level terrace. Back of the terrace is upland cons'sting mostly of broad, flat hilltops reaching an elevation of 200 feet. Most of the Refuge is forested, with many of the previously cultivated areas now covered by pine or sweet-gum stands. The floodplain forest is composed entirely of hardwoods. The terrace and upland fo:est consists cither of mixed pine and hardwoods, hardwoods, or pure stances of pine. The latter are usually even-aged and are found in previously cultivated fields. A description of all habitat types on the Refuge is given by Hotchkiss and Stewart (1947). Capture sites of the eight species of fur animals under discussion, plotted on a vegetational map of the Refuge, showed that four habitats were outstanding. A brief description of these follows: