Proximate Factors Limiting Population Growth of White-Tailed Deer in Nova Scotia

Abstract

White-tailed deer (Odocoileus virginianus) densities in Nova Scotia, Canada, declined during the late 1980s and early 1990s. We estimated population change, survival, and relative importance of mortality factors for deer in 2 geographic areas of Nova Scotia from February 1994 to January 1999. Pellet-group surveys indicated that deer densities in both study areas increased slowly (λ was approx. 1.07 and 1.05 in the Queens County and Cape Breton study areas, respectively) during the study. Annual survival rates of adult deer did not differ among years or between the study areas. Annual survival rates for adult females averaged 93.9 ± 4.3% (SE) and 80.4 ± 3.1% within and outside of Kejimkujik National Park, respectively, where harvest did not occur. Annual survival rates of adult males and fawns outside of the park, where hunting occurred, were 50.7 ± 7.6% and 36.9 ± 7.4%, respectively. No marked adult males or fawns died within the park during the study (winter only for fawns). Annually, hunting (34.2 ± 8.2% and 8.2 ± 2.4% for adult males and females, respectively) and predation (7.2 ± 5.3% and 7.5 ± 2.3% for adult males and females, respectively) were the largest mortality factors for adult deer. Coyote (Canis latrans) predation (27.5 ± 8.7% during Dec-May only) was most influential for fawns. Monte Carlo simulations involving a model of adult survival and fawn recruitment supported the results of the deer pellet-group inventories and suggested low but positive rates of increase for both populations. Although predation and the unregistered harvest of adult females probably slowed the growth of deer populations following the decline, the recent establishment of a zone-based antlerless harvest quota system should allow managers to regulate deer numbers by annually adjusting the number of antlerless permits in response to estimates of hunting and nonhunting losses.