A long-distance migrant that winters in South America, the once abundant and familiar Common Nighthawk was assessed as Threatened by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), due to steep population declines (COSEWIC 2007c), and listed as such under the Species at Risk Act. However, in 2018, it was reassessed as being Special Concern by COSEWIC because the southern population appears to be stabilizing and the northern population appears to be larger than was once thought (COSEWIC 2018). The results of the Breeding Bird Survey show large decreases across Canada since the early 1970s, though the reliability of this assessment is considered to be medium due to lack of coverage in the north. The causes of this long-term decline are unclear, but likely stem from multiple sources (Environment Canada 2016c, Brigham et al. 2011). This species has been identified as a priority for conservation and/or stewardship in one or more Bird Conservation Region Strategies in Canada.
In the 1980s, there was a negative change point in the Breeding Bird Survey population trends of swallows, swifts, and nightjars across most of North America (Smith et al. 2015). Indeed, the Common Nighthawk is one of several species of aerial-foraging insectivores showing widespread declines in Canada. Causes of these declines remain unclear, but changes in aerial insect populations have been suggested as one possible common factor as well as landscape changes, insecticides, and climate change (Blancher et al. 2009, Nebel et al. 2010). Particular to this species, habitat loss and modification through fire suppression, reforestation of fallow fields, intensification of agriculture, and a reduction in the availability of their preferred nesting substrate in urban areas (e.g., gravel rooftops) are thought to negatively affect the species (Environment Canada 2016c). For information on the legal status of this species under the Species at Risk Act (SARA), see the SARA Registry.
Environment and Climate Change Canada and partners have developed Bird Conservation Region Strategies in each of Canada’s Bird Conservation Regions (BCRs). In these strategies, selected species are identified as priorities for one or more of the following reasons:
Select any of the sub-regions below to view the BCR strategy for additional details.