Effects of Prescribed Burning and Cattle Grazing on Deer Diets in Louisiana

Abstract

A study was conducted on the dietary and nutritional effects of cattle grazing and rotational prescribed burning on the diets of three to five captive white-tailed deer (Odocoileus virginianus) on longleaf pine (Pinus palustris Mill.) bluestem (Andropogon spp. and Schizachyriumspp.) sites in central Louisiana from October 1980 through February 1987. Deer diets were evaluated under ungrazed, moderate year-long, heavy seasonal, and heavy year-long cattle grazing treatments. Deer diets were composed mostly of browse and forbs under all grazing treatments, but were less diverse under heavy grazing when compared with moderate and no grazing treatments. Foraging efficiency (computed as the ratio of forage intake per 30-minute trial to the distance traveled) was comparable among treatments during spring and fall but was lower under the heavy grazing treatment during summer and winter. Diets selected under ungrazed conditions contained the highest percentage of uncommon and ephemeral plant taxa during all seasons except fall. Dietary crude protein (CP), phosphorus (P), and calcium-to-phosphorus ratios varied significantly under various grazing treatments for certain seasons. Prescribed burning did not significantly affect diet diversity; however, diets from areas of first-year burns were higher in CP and P than from areas of older burns during spring and summer, but these differences disappeared by the first fall after burning. From a nutritional standpoint, burning and seasonal influences generally had more impact than grazing treatments on deer diets. No evidence was found that seasonal or yearlongcattle grazing at moderate levels (40-to 50-percent herbage removal) adversely affected deer nutrition.

Citation

Thill, Ronald E.; Martin, Alton, Jr.; Morris, Hershel F., Jr.; Harrel, Austin T. 1995. Effects of Prescribed Burning and Cattle Grazing on Deer Diets in Louisiana. Res. Pap. SO-289. New Orleans, LA: U.S. Department of Agriculture, Forest Service, Southern Forest Experiment Station. 20 p.