NOAA plans ecosystem-based fisheries management study for Gulf of Alaska

NOAA Fisheries research
biologists say they are embarking on a new ecosystems-based fisheries
management study on the Gulf of Alaska, with a focus on the fisheries and
coastal fishing communities.

The new project, to run for
three years, is funded by the North Pacific Research Board in Anchorage and
internal funds from NOAA’s fisheries and climate program, said NOAA Fisheries
researcher Martin Dorn, the project lead. 

The Gulf of Alaska study
comes on the heels of the Bering Sea ecosystem-based fisheries management
study, said fellow NOAA Fisheries researcher Kirstin Holsman.  Both are with NOAA’s Alaska Fisheries Science

While the Gulf project will
closely follow the one done in the Bering Sea, it is designed to address some
of the environmental and management issues important in the Gulf, Dorn said.

“It is essentially trying to
project what the future might look like for the Gulf and try to figure out what
implications are for marine resources in the area and how that might affect
fisheries and fishing communities,” Dorn said. “We are trying to bring that
whole big package together.”

In the wake of the heat wave
that hit the Gulf from 2013 through 2016, causing the crash of the Pacific cod
population in the Gulf, researchers want to better understand how that heat
wave affected the overall ecosystem and whether that type of marine heat wave
will occur in the future, he said.

Researchers will also study
another aspect unique to the Gulf, that the Gulf has the third largest
accumulation of glaciers in the world after Antarctica and Greenland. Projections
are that glaciers that surround the Gulf will be retreating and melting,
bringing fresh water into the ocean, and there will be greater runoff, Dorn
said. Researchers want to know how this will impact the ecosystem, along with
aspects of climate change, including overall warming, decreased oxygen in the
water and ocean acidification.

Other questions they hope to
answer are how these changes will impact halibut, Pacific cod, Alaska Pollock,
black cod and other species. While fish populations have the ability to adapt
to certain changing conditions, fish in the Gulf are essentially in a bowl with
land all around, and there is no way for them to escape to cooler waters, as
fish in the Bering Sea can do, he said.

There are also concerns that
the Gulf may be subject to invasions of populations from further south, like
Pacific whiting or hake, and some rockfish populations might move northward
too, Dorn said. Rockfish would potentially compete for food and that would
cause a shift in the populations, he said. 

Black cod are another story.
“That population is increasing now and it seems a lot of that came about from
recruitment to the population during the heat wave,” he said. “We don’t have
any proof, but it is possible that sablefish do better under those conditions.”