AN EPIZOOTIC OF HEMORRHAGIC-DISEASE IN WHITE-TAILED DEER (ODOCOILEUS-VIRGINIANUS) IN MISSOURI - NECROPSY FINDINGS AND POPULATION-IMPACT

An epizootic occurred among white-tailed deer (Odocoileus virginianus) from July through October 1988 in Missouri (USA). From late July thro ugh September, nine necropsied deer had lesions of the peracute or acu te forms of hemorrhagic disease (HD) or no apparent lesions, whereas t wo deer necropsied in October had lesions of the chronic form of HD. E pizootic hemorrhagic disease virus was isolated from two necropsied de er. Based on changes in population indices, there is evidence that dee r populations declined in seven of Missouri's 57 deer management units from 1987 to 1990. Based on a deterministic model designed to simulat e deer populations in management units, it appeared that summer and fa ll 1988 mortality ranging from 6% to 16% accounted for the population decreases in deer management units with population declines. Heavily h unted areas where high deer mortality was not reported in the summer a nd fall of 1988 did not have population declines. Based on these resul ts, we believe that IID mortality was high and resulted in deer popula tion declines in parts of Missouri when combined with hunting harvest.