Diet

Figure 4. Seasonal variations in the diet of desert mule deer.

Figure 4. Seasonal variations in the diet of desert mule deer.

Diet

Nutrition is a critical factor in deer management, whether management objectives call for trophy antlers or high numbers of deer. Mule deer diets center around two vegetative components-forbs and browse. Forbs are annual or perennial broadleaf herbs (“weeds”) and are generally highly preferred when available. Forbs comprise from 20 to 40 percent of the annual diet, especially during spring and summer. The staple of the mule deer’s diet however, is browse (leaves and stems of woody plants). Browse comprises from 40 to 70 percent of the annual diet and is especially important in fall, winter and early spring (Fig.4).

Class Season of Use
Species Spring Summer Fall Winter Preference
FORBS
Euphorbias X X X High
Bladderpods X X High
Globemallow X X X Medium
Filaree X X High
Milkwort X X Medium
Plantains X X X High
Sagewort X X Medium
Goldeneye X X X Medium
Daleas X X Medium
Bluets X X Medium
BROWSE
Apache plume X X X Medium
Acacias X X X Medium
Ceanothus X X X X Medium
Ephedra X X X Med-High
Hackberry X X X High
Oaks X X X X Med-High
Mesquite X X X Low
Redberry Juniper X X Med-Low
Skunkbush sumac X X X Med-High
Saltbush X X X Med-High
Littleleaf sumac X X X Medium
Snowberry X X X Med-High
Tarbush X Low
Mt. Mahogany X X X X High
Creosotebush X Low
SUCCULENTS
Lechugilla X X X X Medium
Pricklypear X X Low-Med
Sotol X X Med-High
Candelilla X X Med-High
Yucca X X Med-Low

Table 1. Forage Plants Used by Mule Deer in the Trans-Pecos Region

During droughts browse may contribute up to 90 percent of the annual diet. Grasses generally make up less than 5 percent of the annual diet. Fruits and nuts (acorns, mesquite beans, cacti tunas, etc.) are seasonally important items, as are succulents such as lechugilla and prickly-pear. Common forge plants for different locales are listed in Tables 1 and 2. Deer readily accept most farmed forages (e.g., small grains, alfalfa) and damage to fields can be severe during fall and winter if deer densities are high.
Class Season of Use
Species Spring Summer Fall Winter Preference
FORBS
Bladderpods X X High
Globemallow X X Medium
Primrose X X High
Ratany X X X High
Doveweed X X X Medium
Camphorweed X X X Medium
Ragweed X X Medium
BROWSE
Sandsage X X Med-Low
Hackberry X X X High
Oaks X X X X Med-High
Mesquite X X Low
Redberry Juniper X X Med-Low
Skunkbush sumac X X X X High
Saltbush X X Med
Mt. Mahogany X X X X High
SUCCULENTS
Pricklypear X X Low
Yucca X Low