Application of Multiple Aerial Sampling to a Mark-Recapture Census of White-Tailed Deer

A helicopter-assisted mark-recapture study was conducted on a white-tailed deer (Odocoileus virginianus) population in northern Ohio from late January to early February, 1975. Two hundred and thirty-four deer were marked with collars on the National Aeronautics and Space Administration's Plum Brook Station. The 2,176-ha facility was completely enclosed by a 2.44-m chain-link fence. Collared deer were visually "recaptured" by systematically surveying the Station by helicopter. The population estimate was 2,499 with a 0.95 confidence interval of 2,405-2,593, a density of 115/km2 (298/mi2). Compliance with model assumptions was investigated through a study of animals on a 122-ha Test Area separated from the rest of the Station by an interior fence. Modifications employed in this census effort eliminated many of the problems commonly encountered in mark-recapture work. Procedures for selecting the opti- mum combination of marking and sampling effort in future applications are presented. J. WILDL. MANAGE. 41(2):197-206 The mark-recapture method (Petersen 1896, Lincoln 1930), used extensively to estimate fish and small mammal popula- tions, has not found wide application in big game censusing. Requirements for intensive sampling and equal probability of recapture for all animals are major obstacles. Strand- gaard (1967) used the mark-recapture method to estimate the size of a roe-deer (Capreolus capreolus) population. Deer were marked with collars and visually sam- pled from an automobile. Strandgaard found his census procedure to be unsatis- factory because deer observed along the roadway did not constitute a truly random sample from the total population. However, aerial observation for recapture of marked deer can potentially solve this problem. Woolf (1973) was one of the first to use the aerial sampling approach. He marked ap- proximately 10 percent of 1,000 deer and sampled the population from a helicopter. Visually sampling deer from the air im- proves compliance with the assumption of