Herring critical to forage base in Gulf of ME

June 01, 2005

Commercial Fisheries News
By Janice Plante
Found at: Commercial Fisheries News

PEABODY, MA It’s not just bluefin tuna fishermen who are worried that something isn’t right in the Gulf of Maine and beyond. Others are becoming increasingly concerned too. Forage fish seem to be absent all too often–-not just herring but sand lance and other critical prey species. And traditional spawning grounds seem to be shifting.

These and other fundamental ecosystem issues came up during a May 18 open discussion about herring’s role as a forage species. The New England Fishery Management Council’s herring committee, which was ending a two-day meeting, scheduled the discussion to gather more information about the topic for draft Amendment 1 to the herring plan.

Several members of the bluefin tuna fishing community attended the session for one primary reason. For several years now, they’ve been troubled by the lack of availability of tuna in the Gulf of Maine, and they hypothesize that the valuable big fish aren’t staying in the gulf because they don’t have enough to eat.

They blame midwater trawlers for breaking up herring schools to the extent that the remaining concentrations aren’t large enough to hold bluefin on traditional feeding grounds.

The midwater trawl fleet vehemently denies that this is the root of the tuna problem.

Harpooner Steve Weiner said, “When we fish, we notice our surroundings. We look for birds, we look for whales, we look for porpoises, we look for slicks.”

These signs of activity often signal the presence of bluefin.

But Weiner said the picture has changed in recent years.

“We’re seeing no life in the Gulf of Maine in the summertime. Whether it’s a local depletion problem, I don’t know, but everything is trending downward,” he said.

Robert Fitzpatrick of Maguro America said the evidence was clear by looking at bluefin coming across the dock.

“The fish literally don’t get fat like they used to,” he said.

Local depletion

The term “local depletion” dominated the discussion, and biologist Matt Cieri of the Maine Department of Marine Resources, who answered numerous questions for the committee and audience about herring assessment issues, encouraged the committee to define the term.

“I think that’s the first step,” he said. “There hasn’t been a good definition. It would be useful if you could define geographic and spatial scales.”

Weiner strongly supported this approach.

“A definition of localized depletion would be great. Then we could try to measure it,” he said.

But many in the room already had their own views about the definition, including Gloucester fisherman Michael Blanchard.

“Localized depletion to me is going out tuna fishing, having the fish be there, and then having midwater trawl boats go there the next day. They take such a massive volume of fish that nothing gets away,” he said.

Rich Ruais, executive director of the East Coast Tuna Association, added, “It doesn’t take a rocket scientist to know that something’s going on. I think we all agree that a long-term strategy for looking at localized depletion and forage is extremely important.”

Acoustic work

Committee member David Pierce of Massachusetts was convinced that acoustic survey work was key to getting to the heart of many unanswered questions.

“Acoustic work shows a lot of promise,” he said. “When a trawler comes in or a purse seiner comes in or when multiple boats come in to fish intensively, it’ll help us determine the size of the schools, the movement of schools, how they split up, how they re-form, how they respond to repetitive trawling.”

“We need to put more of a focus on acoustic research,” Pierce said.

Committee member Dana Rice of Maine wanted to see acoustic work all focus on spawning beds, too.

“In Maine, we do identify spawning fish,” he said. “But what has fallen through the cracks is identifying spawning grounds. That work has disappeared. We need to see if those spawning grounds are still there.”

Seals

Rice also questioned the impact that seals, which are protected by law, are having on the herring population.

“They are voracious predators,” he said. “Are their numbers getting so high that they’re impacting the basic forage supply?”

Committee member Rip Cunningham of Massachusetts said he was sobered to read the seal/prey statistics included in a background paper on herring as a forage species.

Scientists estimated that harp, hooded, grey, and harbor seals in Atlantic Canada consumed 83,688 metric tons of herring in 1996 alone.

“I was staggered by the number,” he said.

Tuna buyer Mark Godfried of F.W.F. Inc., who has been tracking the issue, added, “The numbers in that document only go to 1996. The Canadian pinniped numbers are much higher now.”

More to the problem

Jimmy Ruhle, a North Carolina fisherman who sits on the Mid-Atlantic Fishery Management Council, encouraged the committee to look beyond herring while addressing the forage issue.

“Something is taking place in the inshore waters that has driven everything offshore. I’m very convinced there’s a lot going on. Whatever is driving away all the small prey is going to result in a decline in predators,” he said.

“Is there a possibility that there’s a water quality issue or a salinity issue in the Gulf of Maine? There are too many species that are on the decline,” he said.

Ruhle cited an example close to home in his own life.

“As long as I can remember, Loligo squid had traditional inshore spawning areas. Last week, we encountered brand new spawning beds in 102 fathoms of water. I have never in my life seen them so deep,” he said.

According to Pierce, oceanographic conditions are certainly at play.

“The North Atlantic Oscillation has a tremendous influence on water currents –getting water onto Georges Bank and off Georges Bank, there’s cold water going into the Gulf of Maine and going out.

“Understanding how this oscillation impacts the movement of species is critical,” he said. “We need to get more information and have more research about how this affects yearly trends. Sand lance are affected in a big way.”

Many in the room said they found the open session to be extremely interesting.

Cunningham said, “I just want to reemphasize that herring as a forage base impacts a number of fisheries that are extremely important to us on the council. I would like to see this issue stay high on the priority list.”