March 9, 2022 — The crab pots are piled high at the fishing docks in Newport, Oregon. Stacks of tire-sized cages fill the parking lot, festooned with colorful buoys and grimy ropes. By this time in July, most commercial fishers have called it a year for Dungeness crab. But not Dave Bailey, the skipper of the 14-meter Morningstar II. The season won’t end for another month, and “demand for fresh, live crab never stops,” Bailey says with a squinting smile and fading Midwestern accent.

It’s a clear morning, and he leads me aboard a white-and-blue crab boat, built in 1967 and owned by Bailey since 1992. He skirts a giant metal tank that he hopes will soon hold a mob of leggy crustaceans and ducks his tall frame into a cluttered cabin, where an age-worn steering wheel gleams beneath the front windows and a fisherman’s prayer hangs on the wall: “Dear God, be good to me. Your sea is so great and my boat is so small.”

The churning Pacific is just one challenge Bailey and his fellow crabbers must face. Recent years have also brought outbreaks of domoic acid, which renders crab unsafe to eat, and increasing incidents of humpback whales getting tangled in crab gear. However, there’s another emerging problem that threatens not only Bailey’s livelihood but the very ecosystem that sustains it. I’ve come today to see a tool that could help crabbers manage.

On the counter in the kitchenette, amid bowls of instant noodles and tinned oysters, Bailey shows me a sturdy black tube, about 60 centimeters long, that fits neatly inside a crab pot. When submerged, the contraption measures oxygen levels in the water and, when retrieved, displays them on a separate box with a screen for Bailey to read. The box also beams the data back to scientists at Oregon State University (OSU).

Most marine animals don’t breathe air, but they need oxygen to live, absorbing it from the water as they swim, burrow, or cling to the seafloor. But lately, bouts of dangerously low oxygen levels—or hypoxia—have afflicted parts of the North American west coast, affecting critters from halibut to sea stars. These “dead zones” cause ecological disruption and economic pain for fishers like Bailey, who can’t sell crabs that have suffocated in their traps.

Read the full story at Smithsonian