Observations of white-tailed deer cattle diets in Mexico.

Abstract

Most rangelands in northern Nuevo Leon, Mexico, have been grazed intensely for more than 10 years simultaneously by cattle and white-tailed deer (Odocoileus virginianus texanus). There is a lack of information concerning diet selection of white-tailed deer and cattle in this region. We observed the dietary preferences of these ungulates in northeastern Nuevo Leon for a 6 month period. Two adjacent areas were subjected to rotational grazing (RG) and continuous cattle grazing (CG). Fecal analysis was used to determine dietary overlap of these 2 sympatric ruminants. Cattle diets averaged 70% grasses, 23% browse, and 4% forbs. Deer diets were 63% browse, 24% forbs and 12% grasses in both areas. The preferred species for cattle in both areas were grasses. Deer preferred fortes on the continuous grazed area and grasses on rotational grazed area. Zacate toboso [Hilaria mutica (Buckl.] Benth.) was the most preferred species by both ruminants in both management systems. Differences between cattle and deer diets were significant (P < 0.05). The similarity index was higher on the rotational grazed (23%) than on the continuous grazed area (15%) (P < 0.05). The higher similarity index in RG area may have been a result of the altered forage preferences of deer. Zacate toboso under RG could be an important feed resource in those areas where white-tailed deer and cattle graze in common.