Nesting and brood-rearing ecology of Mississippi Valley population Canada geese

Nesting ecology of Mississippi Valley population (MVP) Canada geese (Branta canadensis interior) was studied during April-June 1985-90 in an 11.2-km 2 study area located in tundra habitats along the coast of Hudson Bay 12 km east of Winisk, Ontario. Brood-rearing ecology was studied during June-July 1988-90 in the same area. Nest initiation occurred 1-6 days (x = 2.5 ± 0.8) before peak spring run-off and was relatively stable for 6 years; median nest initiation dates varied about 9 days between earliest and latest years. Spring phenology was not the primary determinant of annual productivity, but did influence nest density (overall x = 6.1 ± 0.6 [SE] nests/km 2 ); high nest densities occurred in years with an early spring breakup, and low densities in years with late spring breakup