NOAA’s biennial bottom trawl survey is underway in the Gulf of Alaska

A major study of one of the state’s largest marine environments is underway.

The National Oceanic and Atmospheric Administration conducts bottom trawl surveys to compile fisheries and environmental data across the country, and this summer, the organization is in the process of surveying the Gulf of Alaska.

Scientists survey the Gulf of Alaska every other year. NOAA’s bottom trawl survey provides an accounting of the entire marine ecosystem — all the way from the Aleutian Chain to Southeast Alaska.

Ned Laman is the trawl survey’s team lead; he said they’re specifically looking at the water column that hovers just above the seafloor.

“We basically count and identify everything that we catch, and weigh it,” said Laman. “And all of those animals from the fish to the smallest invertebrates are identified and counted.”

Think of it like a computer scanner; NOAA scientists, embedded on fishing vessels, move west to east, counting the Gulf of Alaska’s deepest-dwelling marine creatures – like groundfish and crab. Scientists from NOAA work on fishing vessels alongside skippers and crew to complete the survey.

That data is used for stock assessments – which help set catch limits and management policies for specific fisheries. It also provides information for long term monitoring projects, like water temperature.

Dr. Lyle Britt is the director of the Alaska Fisheries Science Center’s Resource Assessment and Conservation Engineering Division, which oversees the survey. He said both the environmental and fisheries data is crucial – one major takeaway from this year’s survey, for instance, will be Pacific cod numbers.

“No different than the fishermen in this area, I think we’re keenly interested to see how Pacific cod are doing after the heatwave, and what kind of recovery there may be happening for them since then,” said Britt.

It used to take a full year to analyze the data – but advances in technology have shortened that turn-around time. Preliminary stock assessment numbers for species are now available within about three weeks of completing the survey. 

But gathering all that data does still take time. The crew left Dutch Harbor in mid-May and stopped in Kodiak over the weekend. Their next stop is in Seward on their way to Ketchikan, where they’ll wrap up in August.