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Bird brains, wasted

by Jessica Marshall
November 13, 2017 | A version of this story appeared in Volume 95, Issue 45


Crowbar aims to draw crow crowd

Experts on crows and their corvid cousins often object to the derogatory phrase “bird brain” because this group of birds is, actually, really smart. Crows can recognize faces, teach one another, and use tools to gather food, and they show other hallmarks of braininess once thought to be reserved for the cleverest of mammals.

Credit: Shutterstock
Birds with butts: Could we hook crows on cleaning up?
Photo of a crow looking at a cigarette butt.
Credit: Shutterstock
Birds with butts: Could we hook crows on cleaning up?


Dutch designers Ruben van der Vleuten and Bob Spikman have a plan to capitalize on crow know-how to solve a global problem: keeping cigarette butts off the street. It’s not a small issue. Some 4.5 trillion cigarette butts become litter per year, making them the most littered item on the planet. Butts are made of cellulose acetate, a recalcitrant material on its own, and after the cigarette has been smoked, the butts are loaded with toxins including nicotine, arsenic, polyaromatic hydrocarbons, and heavy metals.

The duo’s idea is that crows could be taught to recognize and collect the butts, then drop them in a bird-feeder-like contraption in exchange for a treat. It builds on work by Seattle hacker and writer Joshua Klein, who trained captive crows to use a vending machine he designed. The crows learned to deposit coins found on the ground into the machine, which then dispensed a treat. (You can sign up at his Crow Box website to be notified when the latest machine is ready to order, so you can participate in your own backyard crow behavior experiments. Arduino programming and “basic soldering and assembly skills” required.) Van der Vleuten and Spikman

call their setup the Crowbar. A camera within would verify that a deposited object is indeed a butt and not some other detritus before dispensing a morsel of food. Last month they acknowledged to Fast Company that a first step is to make sure the butts don’t harm the crows. But if the birds can handle them without incident, the project could be a win-win, Klein told the publication.

Crow expert John Marzluff of the University of Washington suggested that we ought to butt out of crows’ business. He did not doubt that the the birds could be taught the job but crowed that people should clean up their own messes instead of leaving it to the birds.

Rank roost


Credit: U.S. Bureau of Land Management
Flushed: This long-eared owl had a foul encounter in the toilet.
Photograph of a long-eared owl with feathers widespread and wet, after being rescued from within a vault toilet.
Credit: U.S. Bureau of Land Management
Flushed: This long-eared owl had a foul encounter in the toilet.

Despite their reputation for wisdom, owls sometimes make crappy choices. As the people at the Teton Raptor Center’s Poo-Poo Project will tell you, it’s fairly common for certain owls and other cavity-nesting bird species to mistake the vent pipes of vault toilets on public lands for hollowed trees—and then to get stuck in the muck below. The Poo-Poo Project is working to spare these birds that horrific fate.

The origin story for the Poo-Poo Project stars Joe Foust, a biologist who netted a boreal owl out of a pit toilet in the Boise National Forest in 2010 after finding a sticky note on the door that said something like “Owl in toilet. Don’t use.” Word reached the folks at the Teton Raptor Center, and they said never again.

The group has designed a simple cover for vent pipes, the chimneylike structures that channel the florid air from the cavities of outhouses skyward. It’s a heavy-duty screen mounted about 2 cm above the chimney top, costs just $30, and takes minutes to install. The design allows the gases to get out, even if the screen is covered with leaves or snow, but doesn’t let shelter-seeking birds in.

The cover is now in use in all 50 U.S. states, and not just for potties. Irrigation, mining operations, and other applications that use hollow vertical pipes have installed the screen. The Poo-Poo Project sold its 10,000th screen this summer, sparing untold numbers of birds—and good Samaritan biologists—from future foul encounters.

Jessica Marshall wrote this week’s column. Please send comments and suggestions to


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