GROWTH OF MOOSE CALVES (ALCES-ALCES AMERICANA) INFESTED AND UNINFESTED WITH WINTER TICKS (DERMACENTOR ALBIPICTUS)

Captive moose calves (Alces alces americana) in Algonquin Provincial P ark, Ontario, were similar in size to most calves of the same age from other regions and of other subspecies. Their general patterns of grow th were comparable to those observed for other northern cervids with a n active growth phase throughout the summer and early autumn followed by a period of slow growth in winter. Maximum average daily mass gains (1.1 kg) were achieved in mid-September and were similar to those obs erved in other studies. Male calves were lar er than females at any gi ven age but males and females showed similar growth rates. Infestation with winter ticks (Dermacentor albipictus) may have caused a reductio n in the mass gain of moose in autumn. If this occurs in the wild, hea vy autumn tick infestation may predispose calves to reduced physical f itness and likelihood of survival during winter. Total length, chest g irth, and shoulder height were all strongly correlated with live mass and may be valuable for estimating the live mass of moose calves under field conditions.