OK, so have you ever wondered about what seems like a small swarm of birds flying out from and back under the bridges you cross on your way wherever? They are not winged trolls, but one of the most abundant species of swallows that live across our globe – Barn Swallows.
As their name suggests, many do nest in barns or under the eves of houses and other buildings. Their original nesting sites were caves, but for whatever reason, they have adapted to manmade structures, with only occasional records in caves. As such, they are one of a half dozen species of birds that have become dependent on humans, including their close relatives, Purple Martins.
And yet, their numbers are relatively stable across their range, unlike Martins, that are in decline. Barn Swallows build their nest in sheltered areas and not in cavities that are much less available. Both species are agile flyers and pluck flying insects on the wing, all the while calling in chatty and melodic calls.
If you take the time to watch, Barn Swallows are quite striking in appearance. Males and females are similar in pattern overall with vibrant colors and deeply forked tails. Both sexes have cobalt blue heads and backs. Males have cinnamon-colored underparts, while females are paler underneath. The species name for this bird, Hirunda rustica, reflects this color on males.
If you are brave enough to venture under that bridge from where they are flying, you will find their mud and grass nests, typically built on ledges. Both sexes help build the nest by collecting mud and grass from local wet locations. Up to seven eggs are laid. If you do catch a glimpse of nestlings, they are quite vocal and eagerly open their mouths wide for whatever parents bring to them.
Of course, you don’t always need to crawl under a bridge to get an up-close view of these birds, as was the case for our daughter Abbie. A nesting pair decided that the high, covered entrance way to their condominium was a great place for a nest. The continuous rain of droppings on the steps was a challenge, but hearing the chatter of the little ones for our grandchildren was an education.
As for what these birds do in our world, they are insectivores, feeding on flying insects of all kinds. You will see them flying in acrobatic manner across fields, marshes, and open water, often very low to the ground or just above the water. Their extremely forked tail and contrasting colors help distinguish them from close relatives like Cliff Swallows that also nest in similar places.
If you spot one or both of these fast-flying aerial acrobats, take the time to watch as they snatch insects as they fly, chattering all the while. You might also catch them dipping their bills in the water to grab a drink. Fun!
Hope to see you in our great outdoors!