This study was designed to determine if the relative importance of different habitats changed in tems of population demographics for red squirrels (T~miasczunrr ltzcdsonicz~s) during a spruce cone failure. 1 quantified density, survival, female reproduction, juvenile production, immigration, and animal condition during two years of a spruce cone failure in white spruce, lodgepole pine and mixed conifer habitats in the foothills of west-central Alberta Spmce habitats showed relatively unstable squirrel
densities, a lower proportion of lactating fernales, lower survival, lower juvenile production, lower immigratioq and litîle difference in animal condition relative to pine and mixed conifer habitats. Survival and female reproduction were variable between years for al1 habitats but showed trends for spruce to have the lowest values overall. Adult and juvenile immigration appeared more important in replacing mosn!ity than juvenile production pnmarily in spruce and rnixed conifer, and to a lesser extent in pine
habitats. Given the characteristic fluctuations in spnice cone crops, these results question the historïcal "high quality" rating of white spruce habitat for red squirrels.

Alberta, anthropogenic disturbance, red squirrel