Barn Swallows are aerial insectivores - birds that feed on flying insects. This group of birds (which includes swifts, swallows, flycatchers, and goatsuckers) is experiencing alarming population declines across Canada. Barn Swallows are the most widely distributed and abundant swallow in the world. Although Barn Swallows are still common, the population in Canada declined by about 30% between 1999 and 2009 (According to long term data from the North American Breeding Bird Survey (BBS)). Barn Swallows are classified as Threatened in Ontario, and they have been recommended for protection under Canada's Species at Risk Act.
The reasons Barn Swallows are declining are not well understood, and may include changes on their breeding grounds, wintering grounds, and along migration routes. Potential threats on the breeding grounds include:
Barn Swallow nests are easier to find than many other species' nests. They nest in most rural areas and some suburban and urban areas, in and around human-made structures such as barns, sheds, and boathouses, as well as under bridges and in culverts. Some Barn Swallows nest singly, but many are found in small colonies (usually containing no more than 10 nests).
By monitoring Barn Swallow nests near you and submitting observations to Project NestWatch, you can contribute to a growing database of information that will help us understand Barn Swallow declines.