A striking wildlife migration comes to Portland each fall. It sweeps down the Willamette River from places like Forest Park and Sauvie Island.
“There’s a large movement of them coming from the east around Mount Tabor and Powell Butte and they’re all coming to one point and that is downtown Portland,” says Adam Baz. He’s a bird biologist, so he can’t help but notice them.
They’re crows. Upwards of 10,000 of them every evening and a not-so-subtle reminder that even cities are wildlife habitat.
“Downtown Portland seems to be a very inviting place for crows and I think the reason for that is due to the presence of garbage and food and lights and warmth, and it’s a relatively predator-free environment,” Baz says.
Crows have always been attracted to downtown Portland, but a few years back Jeri Jenkins of Portland Mall Management began to get complaints.
Jenkins’ group is responsible for maintaining much of the infrastructure on Portland’s Transit Mall. So, as the crows increased, so did Jenkins’ headaches.
“They left us a lot of droppings on the sidewalk to clean up, so much so that it just became impossible to keep up with it.”
The organization deployed a Zamboni-like sidewalk sweeper nicknamed the “Poopmaster 6000.” But it was no match for the fouling of fountains and bus shelters. So, Jenkins got online to see if she could find some other way to address the problem.
“What I found is that it’s an issue for urban areas nationwide, but nobody had a solution for it.”
Traditional hazing methods such as pyrotechnics and loud noises wouldn’t work in a densely populated area. So, Jenkins had to get creative. Portland Mall Management wanted a solution that was humane, backed by the community, and that kept downtown crow-poop-free. She hit a lot of problem solving dead ends.
“And then I had a friend say to me, ‘Have you thought about falconry?’” she recalled.
The ancient practice of using birds of prey to manage nuisance birds has become popular with growers of berries and wine grapes.
It was also a very “Portland” solution. But without funding, it remained just an idea. So, Jenkins reached out to Lynnae Berg of Downtown Portland Clean and Safe, an enhanced service district supported by downtown businesses.
The idea was untested. But Clean and Safe was interested enough to get in touch with Kort Clayton, a biologist who’d turned his falconry hobby into a business. Clayton’s falconers and their Harris hawks got to work early 2017.
“There were a lot of unknowns going into this. One of the most obvious was how well the hawks would operate at night. We also weren’t certain how well the crows would respond to hawks,” says Clayton.
The results were surprising.
“We discovered first off, the hawks were fine with all of the crazy things that are happening in downtown. They get up in the trees and follow us around and they work great,” he says. “And we also discovered that the crows responded consistently and reliably to the presence of our hawks; they retreat. It’s really that simple.”
The hawks don’t need to do much to get a rise out of the crows; their mere presence triggers the crows’ natural aversion to raptors and causes them to flee. After two years, it looks like Portland’s crows are developing a preference for more park-like — and relatively hawk-free — settings.
“So far, I think it’s been a big thumbs-up. We’re seeing them move out of the areas that were most problematic and really that downtown stays more clean,” reports Berg.
But will this novel solution fix the problem long-term?
“Crows are incredibly intelligent. They are some of the most intelligent species of birds on earth and part of the reason they’re so intelligent is because they are highly social and so they learn from one another,” explains Baz, who is also part of Clayton’s falconry team. “We’re hoping that by teaching this group of crows that (downtown) is not a particularly safe place, they will teach other crows to find safer, more sustainable places to spend the night.”