“When the Swallows Come Back to Our Exhaust Fan…”
Did you know that tree swallows have seriously decreased in numbers here in North America, especially in areas where English sparrows have multiplied. Non-native birds, English Sparrows are miserable, aggressive neighbours. They’ll chase adult tree swallows away and hog the food and best nesting sites. They will also invade swallow nests, kill the adult birds, eat their eggs and destroy their chicks. Heartless things, they lay their own eggs on top of the corpses and pick away at the remains.
Swallows may find a remote abandoned building where sparrows don’t hang out, or they may find humans who are blind enough —or kind enough— to let them live close by, where sparrows and other predators won’t venture. All the better if there’s an opening easy to defend. At least that’s what one pair of tree swallows must have thought in the spring of 2010, when they found the cover of our exhaust fan missing.
There’s a small hole in the outside wall of our mobile home just below the roof, where the bathroom fan is vented. It’s supposed to have a covering but this fell off sometime, leaving the recessed pipe about one and a half inches in diameter with one end open to the great outdoors. Tree swallows checked it out and found an entry just their size in a wall warmed by morning sun and a nice interior ledge with ample room for a nest. Thus began our own personal experience with swallows.
They set about furnishing their digs. We took note of their presence when a few straws started falling onto the bathroom counter but since we never used that bathroom fan anyway–it was far too noisy and rattling–it seemed a worthwhile nature lesson to observe this process. (Beside which, there was no way on earth we could get them out.) We taped the switch so the fan couldn’t be turned on by unsuspecting visitors and watched the swallows make forays past our window as they built their nest.
In time we heard tiny peeps coming from behind the fan. We dusted shreds of grass from our bathroom counter and smiled at the baby racket we heard when lunch was served — an all-day affair. Our cat was intrigued but helpless to disturb the birds — as were the outside cats. Weeks passed and peep volume grew.
One day I was in the bathroom brushing my hair when the peeping suddenly hushed. Then I heard the unmistakable tones of marching orders; it sounded like a parent bird laying down the law to indolent offspring just like human parents sometimes do. Followed by tiny feet scrabbling on wood, then the bathroom was silent.
I hurried to the kitchen and looked out the window just as the air exploded with swallows. Back and forth the young birds swooped and dived, getting their bearings in this new world into which they’d been shoved. They still called the nest home and for days after, whenever we passed that side of the trailer, we saw a tiny black head poking out the hole as someone prepared for takeoff.
Then the offspring moved out for good. For the rest of July we watched them zip through the sky or balance on wires, learning the ropes, feasting on mosquitoes and other insects. Swallows are entertaining acrobats and can clean up a fantastic number of bugs, especially mosquitoes, every day.
Shortly after their babies left, Ma & Pa Bird were back behind the bathroom fan scratching around. New peeps started coming through the wall and the cycle repeated itself: comings & goings increased; the peeps got loud again. I happened to be there again when another set of marching orders were issued. I could almost hear a harried parent insisting, “It’s time you were on your own. Get out there and feed yourselves!”
Repeat explosion of swallow swoopers. Repeat dives, twirls, and other aerobatics to strengthen wings. More birds on the clothesline.
The bathroom fan is vented not far from our outside tap, so we were often near their nest, but they never minded our coming and going. One or the other would often have its head out watching as I turned the tap on or off. I’d even talk to it from about two metres (6′) away and it never moved.
The next spring I learned an important lesson: don’t put out inviting bird food (i.e. sunflower seeds & nuts) for larger birds like grackles anywhere near the swallow nest. Our bird feeder, hung on a post in the lawn, was too close to the bathroom vent and the swallows were obviously distressed by the presence of bigger birds at the feeder. Several times I saw them dive at grackles sitting there. That spring the swallows raised only one batch of babies, then left.
The swallows used the exhaust fan vent for two summers, then moved on to other nesting sites. We’ve put up several more swallow nest boxes over the past six years, all of which are claimed every spring and new broods raised.
Our yard can be bad for mosquitoes, but we’ve noticed that as long as the swallows are around, the mosquitoes aren’t as plentiful. Nice! It would be worth the price of a dozen birdhouses if we’re spared West Nile Virus. The swallows usually leave us at the end of July and head over to the sloughs to feast on the multitudes of mosquitoes there. After that we have to look out for ourselves mosquito-wise.
In the fall of 2010 I read in a gardening magazine that “swallows produce one batch of young every summer.” Well, ours must not have read the rules. Or they felt so secure in their cozy home that they decided on a second family. The ones who occupy the nest we mounted on the garage have raised two broods some summers as well.
Yesterday at leas one family of swallows returned, twittering around and all trying to get into their old nest box just outside my sewing room window. Welcome home, friends!