Estimating mule deer harvest in southwestern Idaho

Unbiased estimates of harvest are important because harvest characteristics are often the only reliable information managers have about individual populations of big game animals. Traditionally, the Idaho Department of Fish and Game used telephone surveys and check stations to estimate harvest of big game animals. Harvest estimates from check stations are likely biased because random sampling procedures are seldom followed. To reduce bias we applied 2 sampling procedures and fishery-access-point methods when establishing check stations for this study. We ran check stations at 4 different access points during the general mule deer (Odocoileus hemionus) season from 1993 to 1997. The 5-year mean harvest as estimated from the check station surveys was 434 (SE=47.79). During the same time period, the mean telephone survey estimate was 458 (SE=67.26). Harvest estimates did not differ between telephone and check station estimates (t4= -0.85, P=0.44). The 2 survey methods also had similar coefficients of variation (F-4,F-4= 2.31, P>0.20). Check station estimates of harvest did not vary among years (chi(4)(2)=6.70, P=0.14), although telephone survey estimates of harvest did vary among years (chi(4)(2)= 19.34, P<0.001). The lowest estimated harvest from the telephone survey was 228 (SE= 73.00) in 1993, and the highest was 627 (SE=58.00) in 1997. Harvest counts from non-random check stations did not accurately index harvest estimates from the access-point method (F-1,F-3=0.861, P=0.422) or the telephone survey (F-1,F-3=2.16, P=0.238). Accuracy of information collected at check stations can be improved with careful sampling design, but unless biological information is required in addition to estimates of harvest or hunter effort, telephone surveys provided the same information at lower cost.