NOAA Fisheries said it has developed new scientific models to predict changes to the Eastern Bering Sea due to climate change and has found large shifts for commercially important species.
In a release, NOAA said the study found several economically important species will see shifts in their summer distributions, with most shifting north by between 50 and 200 kilometers by 2080.
Included in those shifts are large declines in the amount of the area red king crab, snow crab, and potentially northern rock sole occupy in the southern months; an increase in the area occupied by arrowtooth flounder, which is a predator of pollock; and declines in probability of occurrence of most species in areas with low pH and oxygen concentration.
“As a subarctic ecosystem at the sea ice margin, the eastern Bering Sea is warming faster than much of the global ocean, resulting in the rapid redistribution of key fishery and subsistence resources,” said Maurice Goodman, the lead author of the study and a NOAA Affiliate with the University of Alaska Cooperative Institute for Climate, Oceans, and Ecosystems Studies.
NOAA Fisheries has been grappling with how to manage commercial stocks it oversees amid the impacts of climate change. Climate change has already been blamed for the sudden and catastrophic collapse of Alaska’s crab population, which saw 5 billion crabs die during a marine heatwave attributed to the affects of climate change. That incident forced the state to shut down its lucrative crab seasons and was later declared a resource disaster costing millions.
Being able to anticipate or account for those events will be increasingly important, Goodman said.
“We need to provide resource managers, fishermen, and coastal communities information so they can make informed decisions about how to adapt to these changing conditions,” he said.
As part of the study, scientists built multiple distribution models for eight species: walleye pollock, Pacific halibut, Pacific cod, arrowtooth flounder, northern rock sole, yellowfin sole, snow crab, and red king crab. The scientists used 40 years of scientific surveys with a high-resolution oceanographic model to make a more accurate prediction of how those species could shift.
“To date, most studies projecting marine species distributions rely principally on temperature and static habitat characteristics such as depth. This can potentially lead to significant underestimation of species vulnerability to climate change,” NOAA Fisheries said.
One of the challenges to the model, according to Jonathan Ream – a co-author of the study and a fisheries biologist at the Alaska Fisheries Science Center – was determining the probability of certain outcomes when there are still unknowns in the oceanographic system.
“We compared projections among different types of models to quantify the sources of uncertainty when including these novel factors (pH, oxygen, and the cold pool) in species range projections,” he said.
NOAA Fisheries said the new research will help the agency build on existing distribution modeling efforts and factor in more variables beyond things like temperature to create more accurate predictions of how species will shift due to the impacts of climate change.
“What’s really exciting about this research is we are now able to construct long-term species range forecasts, which incorporate a wider array of climate impacts,” Alaska Fisheries Science Center Research Fishery Biologist Kirstin Holsman, another co-author of the study, said.
