Abstract
This paper examines, from an ecological perspective, the founding frequencies of three organizational forms of cooperatives in Atlantic Canada from 1940 to 1987: worker cooperatives, consumer cooperatives and marketing cooperatives. The findings show that cooperative foundings are sensitive to institutional change as well as to the level of prior foundings, deaths, and population density. The pattern of these effects, however, varies across organizational forms, suggesting substantial differences in the ecologies of populations of cooperatives.