Foraging ecology of Greater Snow Geese, Chen caerulescens atlantica, in different Scirpus marsh plant communities

Abstract

We studied the foraging behaviour of Greater Snow Geese staging in the Montmagny sanctuary in Québec during the autumns of 1985 and 1986, and the springs of 1986 and 1987. We characterize four distinct Scirpus marsh plant communities and compare foraging behaviour of Greater Snow Geese when using these plant communities. We found that geese spent more time grubbing (feeding on underground parts of plants) and did so with greater success in autumn than in spring. Habitat type also influenced the activity patterns of geese; feeding success of geese was reduced in the poorest marsh communities (in terms of food availability and substrate characteristics) and they spent more time searching for food in this community than elsewhere. Search speed (number steps/minute) was also highest there. Maintenance of the primary production of Scirpus marshes of the St. Lawrence River above a below-ground primary production of <200 g/m2, within the perimeter of fall staging no-hunting Greater Snow Goose sanctuaries, should be a primary management objective. Biophysical characteristics of the marsh should be taken into account to avoid areas inappropriate for foraging geese if new bird sanctuaries are to be established.