Brook trout occupancy in the Mixedwood Plains Ecozone, Ontario

Brook trout presence or absence data were extracted from a compilation of electrofishing sampling data collected by the Ontario Ministry of Northern Development, Mines, Natural Resources and Forestry, 22 Conservation Authorities, Fisheries and Oceans Canada, and the Royal Ontario Museum. Additional site data include tertiary or quaternary watershed codes, the number of sites where brook trout were present, the number of sites where brook trout were absent, the Strahler stream order of the sites, and the mean number of times the sites were sampled during the past (1970-1980) and recent (2000-2010) time periods.