Mortality and Movements of Mule Deer Fawns in Washington

Abstract

Thirty-nine mule deer fawns (O. h. hemionus) were captured in south-central Washington in 1977. The fawns were 1-24 days old and weighed 2.9-9.7 kg. The average age at capture was 6.9 .+-. 5.2 days. Fawns were located daily May-Aug., and monthly through Dec. Average distance traveled by fawns from the previous day''s location during an approximate 24 h period for the first 3 mo. of life was highly variable and averaged 438 m. The mean home range was 257 ha for fawns approximately 60 days old or older. Total mortality was 14 out of 26 radio-instrumented fawns. Predation by coyotes (Canis latrans) accounted for 10 of the losses. Drowning caused 3 deaths, and circulatory collapse accounted for 1 death. Combined fawn mortality was 54%. High variability in average daily distance traveled by individual fawns indicates that age is not reliable as the sole factor for predicting fawn movements. Intensive coyote removal on the study area probably would not substantially reduce total mortality in the fawn population.