With six subspecies found worldwide, the Barn Swallow is the most widespread species of Swallow in the world. They are found on six continents; breeding in the Northern Hemisphere and wintering across the Southern Hemisphere. These birds are aerial insectivores, feeding on insects captured in flight.
Hirundo rustica, the Barn Swallow subspecies that breeds in our area, can be observed most years from late April until early September. They prefer open habitat to forage and can be found across farmland, city parks, sports fields, lakes, rivers and ponds. Barn Swallows are so named because their nests are often constructed on narrow ledges inside covered structures such as barns or sheds. Other popular nest sites include: under eaves trough, beneath bridges, and inside culverts. Nests are constructed of mud and attached both to horizontal and vertical surfaces. When positioned on vertical surfaces nests are semicircular in shape, while those on horizontal surfaces are completely round. Feathers and grasses are used to line the nest.
Despite their wide range, Barn Swallows close to home are in trouble. These birds are now listed as a threatened species on the Species at Risk list across Canada. In Ontario, between 1966 and 2009, Barn Swallow populations decreased by 65% with the largest decreases happening most recently. Several factors are to blame including: habitat loss, pollution and climate change. The increased use of pesticides in the agriculture industry has significantly reduced the number of insects in many areas, resulting in a lack of food. Chemical pollution results in several health problems including neurological disorders, birth defects and death. Modernization of structures has also contributed to habitat loss. Wooden barns, sheds and boathouses that Barn Swallows previously could find access to and nest in, are being replaced with metal structures that are completely sealed. Barn Swallows are often seen making failed attempts to gain access to these buildings. Even if access is achieved, these modern structures, with their thin metal roofs, are often too hot in their upper sections where nesting would occur and therefore not desirable nesting locations.
If you have Barn Swallows on your property, consider leaving these old wooden structures for them to nest in. If you need to replace or have already replaced them, than consider adding a nesting platform to the outside of your new structure. Barn Swallows will quickly accept a nest platform placed under a roof overhang on the side or end of a building. Successful broods have been raised in the presence of humans, where these platforms have been installed. Barn Swallows are quite tolerant of human activity, and watching adults raise their brood is both educational and entertaining. I have constructed such platforms to be installed on the property of landowners where Barn Swallows have previously nested and these modern metal buildings now exist. These nesting platforms are specifically designed for Barn Swallows and differ from other platforms in that the ledge for nesting is only 2.5″ wide. This narrow ledge allows enough room for the Barn Swallow to attach its mud nest, but will prevent other birds that use a platform, such as the American Robin and Mourning Dove, from occupying them.
The biggest problem I have seen with artificial nest boxes and platforms is that they are not put up early enough. The intentions of installing them in spring are great, but too often people wait for nice weather and are too late. The nesting platforms must be installed before the Barn Swallows return, in late April. Birds begin searching for an adequate nest site immediately after returning in the spring and it is never too early to put up a nesting platform. Installing one now will ensure it is ready when Barn Swallows return.
If you are interested in one of these nesting platforms for your property, I am currently selling them for $20 each. Platforms measure 13″H x 7.25″W x 3.25″D and are made from Eastern White Pine. Platforms are left rough and unpainted, making it easier for the mud that Barn Swallows use to make their nests adhere. They are easily mounted to any vertical surface with two screws. For more information on these platforms or to purchase please contact me.
Negative human intervention has led to the decline of Barn Swallows and several other species. Now is the time for positive human intervention to help save a Species at Risk. Consider providing adequate nesting habitat for Barn Swallows if they happen to frequent your property. Simple practices like these are something everyone can do to make a difference.