Key finding overview
Wildlife Habitat Capacity Indicator
The capacity of agricultural landscapes to provide habitat for wildlife depends upon the mosaic of land-cover types and their management. One way to measure the potential of these lands to support populations of terrestrial vertebrates is through Agriculture and Agri-Food Canada’s Wildlife Habitat Capacity on Agricultural Land Indicator.3 The indicator ranks potential wildlife habitat capacity for 15 habitat categories based on an assessment of the use and value of 31 land-cover types to 588 species of birds, mammals, reptiles, and amphibians. Results show that natural areas and unimproved pasture provide the highest values, while cultivated lands, in particular croplands, provide the lowest. Natural lands, including woodlands, wetlands, and riparian areas, can provide all breeding and feeding habitat requirements for 75% of the species assessed, whereas croplands can only provide requirements for 13%.3
Wildlife habitat capacity on the agricultural landscape
In 2006, the average potential ability of the agricultural landscape to support wildlife was lowest in the Prairies, Boreal Plains, and Mixedwood Plains ecozones+, which together make up 92% of the agricultural landscape in Canada.3 Trends for individual parcels of land are variable and depend upon changes in their particular use. Although individual parcels, particularly pasture, provide critical wildlife habitat, the dominance of cropland results in a low overall capacity for much of these ecozones+. The ecozones+ where the agricultural footprint was lighter and the dominant land cover within the agricultural landscape was natural (Atlantic Maritime and Boreal Shield) or unimproved pasture (Montane Cordillera, Western Interior Basin, and Pacific Maritime) had the highest wildlife capacity.3
Change in the average wildlife habitat capacity on the agricultural landscape by ecozone+
Long Description for Change in the average wildlife habitat capacity on the agricultural landscape by ecozone+
This bar graph shows the average wildlife habitat capacity for each ecozone+ with agricultural landscapes in 1986, 1996, and 2006. It shows declining trends in the Pacific Maritime, Western Interior Basin, Montane Cordillera, Boreal Shield, and Atlantic Maritime ecozones+. Small declines were found between 1986 and 1996 in the Boreal Plains and Mixedwood Plains. The capacity in the Prairies ecozone+ remained stable. Change is measured by the habitat capacity index, listed as following: very low habitat capacity is less than 30, low is from 30 to 50, moderate is from 50 to 70, high is from 70 to 90 and very high is more than 90. Changes in average wildlife capacity are presented in the following table:
|Western Interior Basin||70.4||65.4||61.3|
Average wildlife habitat capacity, considering both declines in capacity of some individual parcels and increases in others, declined significantly between 1986 and 2006 in all ecozones+ except the Prairies, where it remained low.3 Conversion of small habitat parcels, such as on field margins in the Prairies,5 are not always detected at this broad scale and could represent further degradation of habitat capacity.3 Overall declines in Canada are due primarily to the intensification of farming and the conversion of natural lands to other land-cover types, such as cropland, that are less suitable to wildlife. From 1986 to 2006, the proportion of agricultural land classified as cropland increased from 46 to 53%.3
Agricultural land management and wildlife capacity
Management practices also influence the ability of the land to support wildlife and sound stewardship through best management practices has had positive results in some regions. The dynamic nature of agricultural landscapes results in beneficial and detrimental land-cover changes happening concurrently.
Northern pintail population, southern Canada
Intensification of agriculture in the Prairies over the last 40 years, including the decline of fallow land in summer and increased conversion to cropland, has impacted nest success of some species of breeding waterfowl.7, 8 For example, a primary cause of the decline of northern pintail is their tendency to nest in standing stubble, mulched stubble, or fallow fields early in the season, often prior to seeding. The reduction of summerfallow and increase of spring-seeding since the 1970s3 has been linked to reduced nest success and a decline in the Prairie northern pintail population.9
Farmers have been working with conservation agencies to reduce the impact of agricultural practices on waterfowl. The planting of winter wheat in the fall in a zero-till seeding practice eliminates the need for spring tillage, thereby reducing disruption to nesting ducks. Application of these practices has increased since the early 1990s10, 11 (see Stewardship).