Owl Boxes and Swallows' Nests
By Lakin Khan
April was a month that swung both ways, one week lagging behind in gloom and rain, the next skipping forward into sunny skies and warm weather. April was also the month that welcomed the return of the swallows, so swift and elegant, swooping across the quads in graceful loops, snapping insects out of the air. Flocks of fifty-plus descended upon Salazar and Ives and began building their mud nests, to the delight of many and the disgust of some. For as much as most of us admire their aerial grace, swift beauty and parental diligence, others (understandably so) are rather put off by the unsightly streaks of bird poop that inevitably run down the walls and windows. (techy aside here: bird poop in large quantities is known as guano, otherwise it's just plain feces; I'll call it poop, if you don't mind.) Some want to encourage the swallows to find other ledges for their lodgings.
But swallows are creatures of habit, known to return to the same nesting sites for centuries; witness the swallows of Capistrano. Washing off the previous year's nests doesn't discourage them one little bit either, but does provide a clean slate by removing bacteria and mites as well, ensuring a healthier home for the new nestlings.
The sparrows don't seem to mind building anew; they heave to with gusto, flying out almost 1,000 times to gather the drips and drabs of mud needed for constructing their nests. Now, if we could only invent long flushing gutters and install them under the nests, catching their droppings before they hit the walls or sidewalks. Or maybe paint so slick the poop won't stick?
One afternoon in the last week of April, a woman who works in Stevenson Hall (aka Owl Hotel) dashed into my Darwin office: an owl was stuck in a tree, mobbed by ravens; could anyone in the Biology Department help? And so the other bird drama of spring, the attacks on the owls by the ravens, played out.
As many from Stevenson can attest, this is a wretched and chilling scene: a trapped owlet, screeching for its life; a band of bullying raucous ravens, eyes glittering, diving in for the kill, pecking and pecking away; the cacophony echoing and reverberating between the concrete walls. Meanwhile the owl parents, in their owl way, watch impassively from the eaves, or so it seems.
Although she had followed protocol and already called Craig Dawson of Environmental Health and Safety, this good Samaritan feared the worst was near for the hapless owl. I had a good hunch Dawson was in a long meeting, so I called the Bird Rescue Center of Sonoma County. The receptionist gave me some instructions and said she'd contact Roberta Chan, who had attempted to capture this same owl the night before. Then we rushed over to the courtyard, hoping that our presence would forestall actual bird-murder.
When we arrived, the ravens had retreated and several people were in the courtyard staring up at a fair-sized owl shifting among the top branches of the magnolia tree. Per instructions, I had a sturdy cardboard box and an old t-shirt to use in case the owl was on the ground, in which case we were to put the shirt (or towel) over the bird and the box over that to protect it while we waited for Chan. Why both species insist on nesting in the Stevenson quad is beyond me; you'd think they'd find less contentious spots. But year after year, the owls pick their corners and the ravens choose their spots, all within spitting distance of each other. And while I once thought that the owls preyed on the ravens as much as the ravens preyed on owls, I have since learned this is not true. The ravens have a taste for owlet, while the owls, who hunt at night in open fields, pass by the nest, well guarded by the raven parental units.
Glancing around the eaves, I noticed no messy conglomeration of sticks and dead leaves in the eastern corners; the two big raven nests were gone. In the two western corners sat four grey-painted boxes with small round entrances. This is all part of a plan to lessen the owl-raven conflict, Craig Dawson told me later by email. Barn owls, as cavity-dwelling and human-tolerant birds, quite readily use nesting boxes, so he had asked Tom Daly to build and install them. This would at least get the littlest ones under cover during raven rampage hours. By dismantling the raven nests, they hoped the ravens would seek other quarters...but, lo and behold, a pair of these bold birds simply built a new nest on the western wall smack dab between the owl boxes. Go figure.
As I needed to return to my office to attend to my other duties as assigned, I wasn't able to wait for Bird Rescue. However, Tanya Robertson, SSU ENSP and biology student, was standing nearby and volunteered on my behalf. Chan arrived soon after, captured the owl easily enough and took it in for evaluation.
While generally it's the owlets who become raven-bait while stuck on a ledge or the ground, unable to fly up to the home nest, this was an adult owl, as I later learned from Roberta Chan. She speculated that it had been badly injured from an avian predator, such as a great horned owl or raptor. Once weakened by that attack, it couldn't fend off the ravens or fly out of their reach. Bird Rescue has great success with the owlets they save from our campus, but this owl was too injured and ultimately didn't survive, sad to say.
It's commendable that we try to accommodate our beasty neighbors on our campus. We could call ourselves WIMBY's: Welcome In My Back Yard. But it's not without its downsides: ugly streaks down the walls, vicious raven-owl wars. It can be uncomfortable witnessing all this messy, bullying, opportunistic, horrifying behavior ... and yet this is what creatures do. Who is to say that at any given time, we as humans function all that much differently? When we share space with our fellow creatures, we have to take their bad with their good and appreciate that they, in turn, have had to do the same.
E-mail our amateur campus naturalist with any observations, stories or reactions you have about our shared environment with the natural world on campus. Khan is an administrative coordinator in the biology department and can be reached at firstname.lastname@example.org.