After witnessing the N.W. Harborton Drive frog slaughter with his friend, Shawn Looney, Rob Lee started making calls and e-mailing biologists and herpetologists.

"I started trying to find the appropriate people to tell about this – that something was going on that we should be paying attention to," he says.

He also approached Jane Hartline, a retired Oregon Zoo marketing director and conservation advocate with a knack for organizing.

No one knew whether the great frog massacre of 2013 was an anomaly or, more likely, an unwitting annual death march. They were determined to find out, to help the frogs if they could, to precisely document everything they observed and to contribute to the scant science on the Forest Park red-legged frog population.

Liz Ruther, a habitat conservation biologist with ODFW, granted Lee, Looney and Hartline a permit to handle the frogs. Without one, it's illegal to touch or harass them, given the species' sensitive-vulnerable status.

With help from The Forest Park Conservancy, Hartline rounded up about three dozen volunteers willing to rush to Linnton with little notice. Their task: spend hours intercepting frogs on wet, chilly nights when most Portlanders were tucked in at home, dry and cozy.