by Donald Hilborn, Director Ontario Barn Preservation.
The Barn Swallow, officially known as Hirundo Rustica, arrives in Ontario each spring expecting the barn doors to be open (side note….our 130 year old barn in Oxford county receives them on April 24th (+/- 2 days)). The 1st floor of an old bank barn is the preferred nesting habitat for these birds (simulating their cave habitat prior to the existence of barns). The ambitious birds quickly proceed… reclaiming, rebuilding or making a new nest in the old barn. Using spit, mud, straw and string, they upgrade the nest, completing it just in time for the eggs. The nest is commonly attached to a side of a beam just under the mow floor. Likely it is located there to gain maximum protection from predators and weather.

Until early August, the Swallows will torment the farm cat, “flit” the farmer and turn the farmstead’s flying insects into protein and a bit of a mess especially directly underneath the nests. Suddenly the birds leave, heading to Central or Southern America, travelling in large flocks, eating while flying, covering up to 600 miles per day. They live an average of 4 years making 7 trips across the border. 50% of the time they somehow come back to the same barn. The farmer will express concern that prized farm equipment is a bit marked with excrement but will have an excellent reason to buy the new fancy pressure washer. After a few years of enthusiastically using the new washer, the farmer typically resorts to removing any nest attachment devices (i.e. protrusions like old nails on the side of beams) within the equipment parking zone. To replace these nesting areas he/she will add new nails in non-equipment locations.
Now each summer at sundown, the farmer can sit comfortably on her/his porch watching the swallows soaring and darting gracefully thru the air, like British Spitfires, decimating the mosquito population.

Information and lower photo from Washington NatureMapping Program.
Leading image from allaboutbirds.com