Researchers tackle Dungeness crab population concerns

When it comes to the state of Puget Sound’s Dungeness crab population, there’s a lot of questions.

You may have noticed higher prices, but according to researchers there’s a decline that may be linked to a range of issues: climate change, ocean acidification, chemicals and/or overfishing.

”I love Dungeness crab to eat,” said Russ Higley, Highline College’s MaST Center Director. “I haven’t been buying them, they’re almost twice the cost because there is no supply.”

According to WDFW, the concern is in South Puget Sound where harvests began declining at unusually high rates back in 2013. Tribal and recreational crabbing peaked above 214,000 pounds in 2012 in one specific area, only to plummet below 9,000 pounds in 2019.

As Higley explains, there’s a lack of data to fully understand the situation. That’s why a number of state, tribal and research entities are teaming up to track numbers across the Sound.

Essentially hand-built traps are being deployed across Puget Sound that have battery-operated lights at night that attract crab larvae. Volunteers remove the contraption several times a week and individually count tiny crabs that won’t be full-grown for another four years.

The data helps them understand what the baseline population is.

”That’s the kicker, how many should be in there?” said Higley. “This is data that by itself is just one point -- so we need years, worth of data to know this is a bad year.”

The overall research began back in 2018, but hadn’t been taking place in south-central Puget Sound until recently. Ashley Benson, a research tech at UW-Tacoma, is one of the volunteers who’s been working on the project since April. She told KIRO 7 that in order to understand the decline you have to understand what the base level population is in any given year.

“In four years these crabs will be adults,” said Benson. “So in four years we can say, ‘We had this many then, what is happening to them in-between those four years.’”