Changes to wildlife habitat on agricultural land in Canada, 1981–2001

Agricultural land in Canada comprises cultivated land, hayland and grazing land with associated riparian areas, wetlands, woodlands, and natural grasslands. Although these agro-ecosystems support many species of Canada’s native fauna, agricultural land use is dynamic, and changes in agricultural practices can have important implications for biodiversity. We report on Agriculture and Agri-Food Canada’s National Agri-environmental Health Analysis and Reporting Program’s assessment of wildlife habitat on farmland in Canada. Habitat use matrices were developed for 493 species of birds, mammals, reptiles and amphibians associated with farm land habitat in Canada. We derived patterns of land use from Statistics Canada’s Census of Agriculture data and applied them at the soil landscape polygon scale. We developed a proportionally weighted Habitat Capacity index to relate habitat use and land use. A 5% decrease in Habitat Capacity occurred on Canada’s agricultural land from 1981 to 2001, associated with an expansion in cropland and a decline in pasture. A regional pattern of small decline in Habitat Capacity is evident in the Prairie Provinces, where dramatic declines in the use of summerfallow had a positive impact on Habitat Capacity. In eastern Canada, greater decreases in Habitat Capacity occurred, associated with an increase in agricultural intensification. Policies and programs designed to sustain biodiversity should not be developed independently of socioeconomic factors or policies favouring agricultural intensification. We recommend a holistic approach to making policy decisions relevant to environmental and economic sustainability in the Canadian agricultural landscape. Key words: Biodiversity, land use change, agroecosystems, wildlife habitat, indicators