Fishtown naturalists are excited over an apparent beaver at Penn Treaty Park (not to scale)

💌 Love Philly? Sign up for the free Billy Penn email newsletter to get everything you need to know about Philadelphia, every day.

Penn Treaty Park was outfitted with a hidden camera last weekend, and a neighbor is planning a stakeout. Others are running surveillance, trying to determine whether they actually saw what they think they saw:

A beaver.

Dozens of Fishtown residents have reported beaver sightings to the park’s friends group. The tell-tale signs are there: bite marks around the base of willow trees on the riverside grounds, which come when the large rodents sharpen their teeth on the bark.

“There’s this influx of people noticing beaver chew,” said Bonnie Schmonsees, board member of the Friends of Penn Treaty Park. It’s a big deal, she said, because beavers are evidence of improvement to the banks of the long-polluted Delaware River.

“If we’re seeing signs of a beaver,” Schmonsees said, “it’s because the land is improving, but it won’t stay that way unless we continue to pay attention.”

When beavers make their dams, they support entire ecosystems of fish, birds and insects. The dam also filters stormwater, and provides structure to the riverbed — helping reduce erosion of the shoreline.

Twenty years ago, there were virtually no beavers in Philadelphia. But parks employees told WHYY last year that they’ve seen more and more of the flat-tailed animals in the last decade.  In 2019, at least four beaver sightings were reported in the city.

Department of Parks and Recreation spokesperson Maita Soukup confirmed beavers often lurk around Penn Treaty park, and their population has been increasing in Philly in recent years.

“It’s always a good thing when you see a species returning or thriving, because that can be a sign that environmental conditions are improving,” Soukup said. “Beavers can have a large impact along our waterways and riparian corridors, especially where we are actively planting new trees and shrubs.”

‘Beaver chew’ on a tree in Penn Treaty Park in 2018 Credit: Courtesy Bonnie Schmonsees

The animals can have downsides. Three Philly residents say they were bitten by a beaver in Pennypack Park in 2011.

Also, they chew trees to sharpen their teeth, slashing even thick willows until they fall down. The task at hand for the folks at Penn Treaty Park, who’ve worked to clear the land of invasive species, is to protect the trees — but also keep the beaver around, so it continues to stimulate the environment.

There was a beaver sighting at the park in 2018, per Schmonsees, but construction on the bike trail scared it away.

Friends of Penn Treaty Park is planning to use part of a $65k grant from the Pa. Dept. of Community and Economic Development to plant more willows, which beavers love. Meantime, the guy is already chewing through the better part of the only two willows on Penn Treaty Park property. The group decided to fence one off completely to protect it — and let the beaver have its way with the other.

They’re also working to confirm that it’s actually a beaver. Plenty of Fishtown neighbors are monitoring the park, trying to catch photo and video evidence of the little guy. That includes Meredith Nutting, an eight-year resident and a career urban wildlife videographer.

She’s hoping her hidden camera will reveal the beaver’s movement patterns, so she’ll know when to visit in person to get higher quality footage.

“Is it a beaver? Is it a nutria? Is it a muskrat?” Nutting said. “Let’s figure out what this is so we can guide the conservation of habitat support that the park might want to do.” (It probably isn’t a groundhog, which are super common in Pennsylvania, but don’t have the same flat tail and hibernate in winter.)

Nutting is pretty psyched about the idea of catching the potential Philly beaver on camera, to spur interest in Philly’s local parks and wildlife.

“If you have footage of a beaver coming up with the Ben Franklin Bridge in the background,” Nutting said, “that interests people into learning more about the habitat they’re living around.”

Michaela Winberg is a general assignment reporter at Billy Penn. She covers LGBTQ people and culture, public spaces, and transportation and mobility. She also sometimes produces radio and web features...