Tuesday, June 20, 2017

As ocean temperatures rise, species move north and fishery management isn't keeping up

Tropical rabbitfish
Oceans are warmer now than they have been since record-keeping began in 1880, which is forcing many aquatic species toward the poles, leaving fishermen with a choice: follow the schools or pursue a different species.

As water temperatures have spiked along the East Coast, the Atlantic Ocean’s inhabitants have undergone a dramatic rearrangement, Ben Goldfarb reports for Yale Environment 360.

"According to an analysis by researchers at Rutgers University, black sea bass, once most abundant off the coast of North Carolina, have shifted two degrees of latitude north, to New Jersey, over the last half-century. Lobsters have all but vanished from Long Island Sound — where rising temperatures have made the crustaceans more susceptible to disease — and, at least for now, proliferated in the Gulf of Maine. Butterfish have supplanted herring in the Gulf, with disastrous consequences for baby puffins, which struggle to swallow the disc-shaped interlopers and starve to death. Even blue crabs, the invertebrate icon of Chesapeake and Delaware bays, have arrived in the Gulf of Maine," Goldfarb writes.

Some agencies and fishing communities have also begun considering the future of seafood. In 2016, National Oceanic and Atmospheric Administration scientists found that around half the Northeast’s fish and shellfish were highly vulnerable to climate change, especially species like shad, salmon and sturgeon, which spend part of their lives in freshwater and must contend with changing conditions in rivers as well as oceans, Goldfarb explains. "A parallel NOAA study suggested that ports whose economic fates are hitched to vulnerable species — like New Bedford, Mass., which depends on scallops for around 80 percent of its landings — face particular risk, while towns like Point Judith, R.I., whose fishermen catch the gamut from squid to monkfish to lobster, could fare better."

As fishermen are left to decide whether to follow the cash or pursue a different species, either way, Goldfarb says that larger-scale fishermen have an advantage, "spelling further trouble for beleaguered 'day boats' whose captains are already burdened by overfishing, stringent regulations, and industry consolidation."

Tom Nies, chairman of the New England Fishery Management Council, warns that small-scale fishermen will have more difficulty adapting to climate change, "because they have less ability to go longer distances, they can carry fewer fish, and they may have less familiarity with fish species in another area."

Regulators have begun incorporating climate change into their decision-making, Goldfarb explains. In 2014, NOAA used water-temperature data to set catch limits for butterfish. But Nies says such case studies have been "few and far between," and most regulations remain rigid. "As summer flounder, black sea bass, and other species migrate north, catch allocations have been slow to follow," Goldfarb writes. "Fishermen in North Carolina hold the highest black-sea-bass quota, for instance, even though the fishery has crept into New England. The absurd upshot is that North Carolinians must motor north for 10 hours to catch their share, while New Englanders often have to discard bass."

In a 2016 letter to the inspector general of the U.S. Department of Commerce, which oversees NOAA, U.S. Senators Chris Murphy and Richard Blumenthal of Connecticut warned, "The impacts of a changing climate will be far more severe if the data used — and regulation that follows — fails to keep pace with environmental changes."

No comments: