Black-Tailed Deer

(Odocoileus hemionus ssp. columbianus)

Deer are perhaps the most widely recognized large mammal in North America. These animals are widespread and very common on campus. The black-tailed deer is a subspecies of the mule deer. Deer are the largest type of wildlife that people encounter on this campus. They are primarily active in the mornings and evenings, but on campus are commonly active in the midday. They have large ears that move independently, hence the name "mule."

The breeding season occurs roughly from the middle of September to December; this period is termed the "rut." Gestation is about 200 days. Does may have one to three fawns, and twins are very common. The young are born in late spring or early summer and will stay with their mother through the next winter. The fawns are rust-colored and have white spots at birth. These spots help to camouflage the vulnerable fawn whilst it is laying in the brush. At about three to four months of age, the spotted fur sheds out and is replaced by a grayish-brown fall and winter coat.

Deciduous antlers grow on the males (bucks) from April to August. Their development is nourished by a soft layer of "velvet." When the antlers are grown out, the velvet dries up and is rubbed off as the buck polishes his antlers for the rut. The antlers are shed in mid-winter.

Deer will eat a wide variety of plants. They browse on leaves, the stems and buds of woody plants including: grasses, poison oak, acorns, fruits and nuts, small grains, fruit trees, and many varieties of garden plants. This is very frustrating for gardeners and groundskeepers who must constantly strive to find ways either to exclude or repel deer, or find plants that are not palatable to them. Deer are also responsible for losses resulting from crop and nursery damage.

Living With Deer

• Deer vs. vehicles pose a serious risk to motorists and quite a few deer are struck and killed by vehicles on campus. BE ALERT AND DRIVE CAREFULLY.
• The best way of controlling deer is fencing. Deer fences should be at least 8' high. The fence should be slanted towards the approach area. Some areas are difficult to deer-proof. For example, garden areas can be quite challenging to deer-proof. It is as if the deer have little springs built into the bottoms of their tiny hooves. Adequate physical barriers can be costly.
• Plant shrubs and trees that are known to be deer-resistent. For a list of plants and trees that are deer-resistent, write to the Resources Agency, California Department of Fish and Game, Resources Bldg., 1416 Ninth St., Sacramento, CA 95814.
• There are some deer repellants that work, but you have to be very dilligent about applying them (this too can be costly for large areas). Contact the Biorational Pest Control Officer for a list of products approved for use on this campus.
• Effigies work for a while, but they must be moved daily, otherwise the deer will habituate to them as long as they no longer perceive them as a threat. The same holds true for scare devices.