Seated on the hard concrete floor of the Wellfleet Bay Wildlife Sanctuary’s maintenance barn, Massachusetts veterinarian Kelly Sattman lifted turtle No. 491 to eye level.
She pressed a small speaker that looked like an old transistor radio up to one ear while holding a sensor to the turtle’s neck.
Sattman tried to parse out the heartbeat from the white noise crackling from the speaker, and the roar of a heater struggling to keep the barn, set up as a turtle triage center on Friday, at 55 degrees.
The count of recovered cold-stunned turtles was 520 on Friday, well past the 2012 record of 413. With survival rates at 80 percent, the sheer numbers of this year’s strandings taxed Audubon sanctuary staff and volunteers and overwhelmed the capacity of the New England Aquarium’s Quincy Animal Care Center, which can handle 70 turtles comfortably, and 120 in a pinch.