SIXTEEN YEARS OF MOOSE BROWSE SURVEYS IN ONTARIO

Abstract

This paper summarizes 51 moose (Alces alces) browse surveys totalling 3,834 plots that were carried out by district Staffs across the moose range of Ontario from 1955-1970. The purpose was to answer questions asked by moose managers concerning food availability and use. In 13 surveys, percentages of twigs browsed were estimated for all species; in the remainder, stems of 10 species were recorded as either browsed or not browsed. Twenty two of 33 recorded plant species were browsed by moose. Beaked hazel and mountain maple provided most food; mountain-ash, alternate-leaved dogwood and juneberry were preferred species but contributed less because of low availability. Balsam generally ranked low in availability and use, but contributed over 90% of the browse on an island. Browsing might have seriously affected the vegetation in 3 of 32 studies, two of them on islands. Since in most of these areas, moose populations were stable and hunting light, moose densities appeared to be regulated naturally below levels that would result in starvation or substantially reduced food supplies. The moose appeared to be generalists relative to major food species within the context of optimal foraging, but constraints imposed by chemical defences greatly reduced or eliminated availability of some plant species.