Rutgers Helps Bring Back the Butterfish as a Thriving Export
Restrictions overturned, New Jersey fishermen expect a 15-fold increase from a decade ago
In the 1980s butterfish were so abundant off New Jersey – and so little used by American consumers – that local fishermen developed a thriving export market.
That was before uncertainty over the butterfish population led government regulators to virtually shut down the fishery in the last decade. Now, with help from scientists at the Rutgers University Coastal Ocean Observation Laboratory (RUCOOL) working with fishing captains, a new assessment shows the population is healthy – and New Jersey fishermen are gearing up to get out there again this winter and feed appetites in both Asia and America.
“It’s going to need to get started, to ramp up, it’s going to need to develop the market,” said Greg DiDomenico, executive director of the Garden State Seafood Association, who helped bring scientists, fishermen and government experts together to work the problem.
The reassessment could bring new jobs to shore fishing ports like Cape May and Point Pleasant Beach during the lean winter months – not just for boat crews, but the shore-side workers needed to box up and freeze a lot of butterfish.
As of Jan. 1, fishermen are permitted to catch up to nearly 22,000 metric tons of butterfish in 2015 – potentially almost twice the peak catch in the glory days of 1984, and a nearly 15-fold increase from “eight years ago, when it was 1,500 metric tons and we were in emergency mode,” DiDomenico said. That could be worth $31.7 million more in revenue just for fishermen, not counting economic spinoffs from sales.
“The fishermen already had a pretty good handle on where the fish were, and were not,” said Josh Kohut, a physical oceanographer and associate professor at the Rutgers Institute of Marine and Coastal Sciences. Another key element was building a digital temperature model – a map that moves in time showing the ocean temperatures preferred by butterfish, developed by Kohut and the RUCOOL group.
“The industry has been saying from what they see out there, there are lots of butterfish,” Kohut said. Captains consider water temperatures to be a critical factor, and the model “acknowledges there is a thermal pattern,” he said.
Bringing together scientists and fishermen – and essentially having them test each other’s models – may show a way forward for other troubled fish stocks and fishing fleets, participants said. That’s a dire need in New England waters, where temperatures and climate change are a major factor in the failure of fish populations to recover.
“One of the exciting outcomes is how powerful this can be when we get in a room together,” Kohut said.
Called butterfish for its rich, fatty flavor, the little fish are loved in Asia and increasingly in North America with the growth of sushi dining. But the butterfish business ran aground in the early 2000s, when the National Oceanic and Atmospheric Administration determined the fish stock’s condition unknown because there was so little good data. A big problem for the old assessment was that sea sampling did not find butterfish as they moved and shifted in response to water temperatures near the ocean floor, seeking their ideals in the mid-50s-degrees Farenheit range.
A team of physical oceanographers led by Rutgers’ Kohut tackled that problem, running computer simulations that drew maps of ocean bottom temperatures going back 40 years.
Those were used as “hindcasts” to develop an index for re-examining the old butterfish estimates, said John Manderson, lead ecologist on the project from NOAA’s Northeast Fisheries Science Center.
“I realized that the Ocean Observing System that Josh had going could be used to do habitat science at a much larger scale,” Manderson said. John Hoey, who runs NOAA’s cooperative research program with fishermen, found funding for experiments.
With a six-week window, Rhode Island captain Chris Roebuck got his trawler Karen Elizabeth ready and “we strapped a glider to the top of the wheelhouse,” Manderson said.
One of Rutgers’ fleet of Slocum electric glider undersea probes, it served as the satellite communications package. Model predictions were transmitted from the Rutgers lab – with its mission control-like wall of video monitors – to Roebuck and Manderson at sea, and they sent back butterfish catches and other data from the boat.
Roebuck calls the joint reassessment “probably the best collaborative project I’ve been involved in…When I took John fishing, that was the first time I had someone with a whole different perspective.”
“They have a deep understanding…those guys know that place like a trout stream in their backyard,” Manderson said of the fishermen. “That’s why you need to engage them in ecosystem management. If their models are wrong, they go out of business. If one of our models are wrong, it gets published in a journal nobody reads.”