Harvesting bighorn ewes: consequences for population size and trophy ram production

We wanted to test whether ewe hunting would cause a decline in population size or in trophy ram production, and whether a reduction in ewe density would increase the size of ram horns. Thus, we examined the consequences of a bighorn sheep (Ovis canadensis) ewe hunting season through an experimental manipulation of an isolated population in Alberta, 1972-91. The number of ewes remained stable during 9 years despite yearly removals of 12-24% of the total ewe population. The removals did not affect (P>0.5) ewe mortality due to other causes, lamb production by adult ewes, or lamb survival