The annual antler cycle in Newfoundland caribou

I studied the occurrence, growth, and size of antlers of caribou ( Rangifer tarandus) in Newfoundland from 1956 to 1966.All the mature males possessed antlers but many females had no visible antlers: 55% in the Interior Herd, 28% in the Humber Herd, and 91% in the Avalon Peninsula Herd.Antlers were first visible in mature stags in April, barren does in May, parous does in June 3 weeks after calving, yearlings in June, and male calves in August.Stags shed their velvet in the second and third weeks of September, 80% of the females shed their velvet 2-10 days before estrus (2-9 October), and 20% shed their velvet 2-3 weeks before breeding.Large stags shed their antlers in November and December, barren does in late March and early April, and parous does shortly after calving in June.The size of antlers was correlated with age, body size, and winter snow falls.Antlers were larger on animals in eastern Newfoundland than in western Newfoundland.