Sunday, November 16, 2014
PRACTICAL LESSONS IN FORAGE FISH MANAGEMENT
This fall, bluefin tuna fishermen anchored up on Jeffreys Ledge off Massachusetts enjoyed the best tuna fishing in at least a decade.
Some of that is due to the presence of the big 2003 year class of bluefin, which meant that a lot of tuna will be swimming around somewhere.
But the reason that the fish were concentrated on Jeffreys, within just a dozen miles of the Massachusetts coast, was a big body of Atlantic herring, one of the bluefin’s favorite forage, that had concentrated over the ledge.
There are few things more basic to fishing, whether sport or commercial, than the fact that big fish will follow the bait.
Atlantic herring spawn during late summer and autumn, and according to the 2012 Atlantic herring stock assessment, Jeffreys Ledge is a major spawning area for the Gulf of Maine stock.
The bluefin tuna, which prey on the herring, “know” this and follow them there. Unfortunately, the big mid-water trawlers that also prey on the herring know this as well, and that’s how one very practical lesson in forage fish management began.
The mid-water boats tow small-mesh nets more than a thousand yards wide, and when they pass through an area, not too many small fish remain in their wake.
Nat Moody, the captain of one of the 75 or so tuna boats that were fishing on Jeffreys Ledge when the trawlers arrived described it this way to a reporter from the Gloucester Daily Times.
“We were fishing around 3 o’clock in the afternoon when they started coming from all directions. There were 10 boats and they started moving through the tuna boats, looking for the biggest (herring) biomass.”
To be fair, the trawlers did nothing illegal. A spawning closure imposed to protect Atlantic herring had just expired, that the boats were merely trying to fill their allotted quota. The same Daily Times article reported that the Massachusetts Division of Marine Fisheries sampled the herring caught by the trawlers and found “no spawning fish at all.”
But, in many ways, that wasn’t really the point.
Michael P. Armstrong, assistant director of the Massachusetts DMF, told the paper that
“We fully expected this conflict.”
“…it’s all about allocation. You’ve got a bite going on. But you’ve also got an industry that hasn’t touched a fish all season.”
On the surface, it looks like a conflict between two groups of fishermen, and an allocation of herring between the trawl and the tuna fleets. But, as Capt. Moody recognizes, the heart of the matter is something else very different and, in the end, far more important.
“This is a flaw in management structure. This is an area and a time frame prime for rebuilding, but management has not taken any steps to protect the food source the whole thing is predicated on.
“This is an area where currently no recreational angler is allowed to catch cod or haddock with a jig for fear of their stocks collapsing. This is an area where gillnetters have been forbidden to fish in the fall due to fears of interaction with dolphins and porpoise. But management thinks it’s fine that the entire herring fleet towing mile-wide nets in 150 feet of water of 5/8-inch mesh at seven knots is a good way to harvest the inshore herring resource.”
Capt. Moody has clearly learned a very basic and very practical lesson; if you want to have healthy fish stocks, and an abundance of the other animals that render the marine ecosystem healthy and whole, you don’t start at the top.
Sure, you need to rein in the harvest of tuna and haddock, to strive to keep porpoises out of gillnets and whales free of entangling gear.
But to succeed, you start at the bottom, making sure that the forage fish base is solid, and then address the higher trophic levels that can only exist if the forage is there.
The good news is that some fisheries managers are beginning to get the message.
In December 2012, the Atlantic States Marine Fisheries Commission adopted Amendment 2 to the Interstate Fishery Management Plan for Atlantic Menhaden. For the first time, under that amendment, the species—which under earlier incarnations of the management plan had been effectively (mis)managed by the commercial reduction fishery—would be managed according to biological reference points for biomass and fishing mortality.
Although there’s not yet any hard data to support the conclusion, conservation advocates in the upper mid-Atlantic region are already pointing to signs of early success as predators swarm into inshore waters to prey on the increasingly abundant menhaden schools. And such predators don’t only include the usual striped bass and bluefish. Thresher sharks approaching the quarter-ton range are being caught within clear sight of shore, while humpback whales sing their enigmatic songs while hunting menhaden right off the beaches of Brooklyn.
Last June, the Mid-Atlantic Fishery Management Council took action to limit river herring bycatch in the Atlantic mackerel fishery, voting to close down the mackerel fishery in any year that too many river herring were killed.
But despite the good news, there’s still plenty of cause for concern.
As Capt. John McMurray pointed out in a recent blog published on www.reel-time.com, there is reason to fear that commercial fishermen in the northeast, reacting to closures of fisheries targeting cod and other overfished stocks might start looking for was to develop markets for forage fish. He references an existing Norwegian fishery for sand eels as an alarming example.
Under no circumstances should such unregulated fisheries be permitted. Forage fish need management, too.
For rebuilding a marine ecosystem is no different than rebuilding a house. You begin not with the upper part of the structure, but with the foundation and frame. And the foundation and frame of the marine food web is the plankton and forage fish that every other element relies on for food.
If those stocks are strong, the entire ecosystem can also be strong and resilient. If those stocks are weak, there is no doubt that, with time, the whole construct will fail.