Mineral Concentrations of Black-Tailed Deer Diets in California Chaparral

Abstract

The monthly level of phosphorus (P), sulfur (S), calcium (Ca), magnesium (Mg), and potassium (K) in the diet of black-tailed deer (Odocoileus hemionus columbianus) in mixed-age chaparral of California was determined during 1985-86. Forage samples were harvested by hand and analyzed using standard analytical methods. Annually, dietary concentrations averaged 0.16, 0.11, 0.49, 0.25, and 0.85% for P, S, Ca, Mg, and K, respectively. Levels of P and S were below the recommended minimum requirement during most months. In contrast, levels of Ca, Mg, and K were adequate during most months. To improve forage quality in mixed-age chaparral managers can implement range improvement practices, such as prescribed burning and chemical and mechanical brush control. J. WILDL. MANAGE. 52(1):37-41 Columbian black-tailed deer are an important big game animal in California. In some habitats deer densities may be low due to forage of poor quality. Most studies assessing the nutrient value of deer forage have been concentrated in the Southwest (Urness et al. 1971, Varner et al. 1977, Everitt and Gonzalez 1981) and Rocky Mountain region (Short et al. 1966, Tew 1970, Wallmo et al. 1977). In California monthly levels of forage quality of selected chaparral species have been determined (Bissell and Strong 1955, Kie 1986), but the relationship between forage quality and deer diet has usually been discussed only in terms of crude protein (Taber 1956, Taber and Dasmann 1958). We report the mineral concentrations of blacktailed deer forage in mixed-age chaparral of California. Forage components were evaluated monthly for P, S, Ca, Mg, and K to identify periods of maximum and minimum forage quality and to detect real or potential problems relating to deer management in mixed-age chaparral. 1 Present Address: EG&G Energy Measurements, % NPR-1, 35R Warehouse, P.O. Box 127, Tupman, CA 93276. This content downloaded from 157.55.39.116 on Sun, 18 Sep 2016 06:41:48 UTC All use subject to http://about.jstor.org/terms 38 BLACK-TAILED DEER DIETS * Scrivner et al. J. Wildl. Manage. 52(1):1988 Table 1. Mean percent mineral compositiona (dry-wt basis) of plant species sampled mid-monthly from June 1985 to July 1986 on the University of California Hopland Field Station.