Top scientists at the National Marine Fisheries Service (NMFS) and fish conservation advocates are reporting a significant increase in the numbers of swordfish swimming in the North Atlantic. Although waters around the Vineyard have yet to see any recovery, the numbers of juvenile fish have improved significantly.
The signs of recovery are dramatic, and scientists expect that if the numbers continue to improve, the fish will make a significant comeback. Not since the restoration of striped bass along the eastern seaboard have fisheries managers been more pleased with the results of their efforts.
Chris Rogers, a fisheries management specialist at NMFS, leaves today for Bilbao, Spain, to attend the International Commission for the Conservation of Atlantic Tunas (ICCAT), the agency responsible for adopting world management plans for swordfish. He is going to the meeting with the hope that though the good news will be received positively, there will be those who will push to keep a conservative posture on the restoration. Opportunists might push for a lowering of quotas.
The story about swordfish managementis complicated and political. Swordfish used to swim within a few miles of the Vineyard, but because of extensive fishing in the Atlantic, their numbers dwindled over the last 30 years. Swordfish spawn in the warmer waters of Florida and the Caribbean where in recent years they were heavily fished. The numbers of swordfish became so depleted that it took international action to protect the fish.
Mr. Rogers said the United States led the replenishment effort. "In 1999 we formalized a rebuilding program to meet the requirements of the Magnuson-Stevens Fishery Conservation and Management Act," he said. "We are now in the second year of that plan." A key component in the act calls on fisheries managers to restore stocks to sustainable levels, ending overfishing.
In the last assessment of the swordfish, the spawning stock size was about 65 per cent of what was needed. In the last year the percentage has risen to 95 per cent. "There is no doubt that this is good news. We are not advocating that the stock has been rebuilt, we are saying that the juveniles are back," he said.
The recovery is due to significant steps taken on the East Coast. The first is that there have been significant area closures totaling 132,670 square miles. Areas where swordfish are known to spawn and those known to contain juvenile fish are closed to longliners. Oceanwide minimum sizes have been adopted, and there have been shifts in the gear used by fishermen.
As a result there are now two significant "year classes" of juvenile fish, which bodes well for the future. "We are going to follow these year classes," said Mr. Rogers.
Beth Babcock is a fisheries scientist for the Wildlife Conservation Society who has worked closely with others on the swordfish crisis. In 1999 the quota was 10,800 metric tons for all participating counties fishing in the North Atlantic. She said last year the quota was dropped to 10,400 metric tons.
"ICCAT has had a size limit of 125 centimeters [from fork length to the lower jaw]. That has been implemented since the mid-1990s," Ms. Babcock said. But establishing a minimum size and lowering the quota wasn't enough.
Who would know whether a juvenile fish could survive if it was discarded over the side? Often times in longlining, the juvenile fish has died by the time it is brought on board. In an effort to further protect the juvenile fish, fisheries managers in the United States went another step and closed large areas to longlining.
"From 1997 to the present the number of juvenile fish is much higher than before," Ms. Babcock said. "We don't have all the reasons why, but the environment has been good to the fish. Combine that with a new fisheries management regime, and the rebuilding has been more rapid than expected."
Anyone who has watched the striped bass recovery in the 1980s and 1990s will understand the issues that are tied to swordfish. Striped bass migrate up the Atlantic seaboard, and in the early 1980s their numbers were so depleted that the states along the seaboard adopted a strict management regime. It was controversial and contentious.
Ms. Babcock said swordfish grow a lot faster than striped bass, and thus the recovery has the potential to take place much faster than that of striped bass. While it takes striped bass almost 10 years to reach sexual maturity, it takes a female swordfish in the Atlantic five years.
It took a decade before striped bass showed signs of recovery and began appearing in Vineyard waters in large numbers. It took many years of good year classes before the striped bass came back sufficiently.
The swordfish recovery shouldn't take so long, though very few adult swordfish have been seen anywhere near the Vineyard.
Two weeks ago a forum was held at the Katharine Cornell Theatre on the status of commercial fishing on Martha's Vineyard. John Mayhew of West Tisbury recalled when he was a young man seeing swordfish swimming between Martha's Vineyard and Noman's Land. Those days are long gone, he said.
Jonathan Mayhew of Chilmark told the Gazette recently that last summer the numbers of sexually mature swordfish were worse than the year before. "Last year [2001] we saw a sign of sexually mature, harvestable swordfish. This summer we saw virtually none," he said.
Ms. Babcock said she can understand Mr. Mayhew's dismal perspective. She said the recovery is first being seen in the juvenile fish, which have yet to swim north - but will. "The 1997 year class was the first good year class," she said. "All subsequent year classes have been high," she said.
The Wildlife Conservation Society is more than 100 years old. It is part of a coalition of environmental groups working to protect swordfish. It also is a member of the Ocean Wildlife Campaign.
Ms. Babcock said the conservation society provided the environmental groups with the science needed to bring their case forward.
She said the issue wasn't just about swordfish, it was also about the overfishing of white marlin - which are now considered to be in severe trouble. The problem with overfishing swordfish is tied to the popularity of longlining, a technique of fishing that involves the use of monofilament fishing line that is 40 miles long with hundreds of baited hooks attached.
Longlining is indiscriminate in its catch; it snares big and small fish alike.
Harpoon fishing for swordfish has a smaller impact. By nature, swordfishermen are discriminating; they only harvest adults because only fully grown swordfish bask near the surface.
Ms. Babcock said the establishment of closed areas, altering the gear to be more selective and setting minimum sizes is why swordfish are coming back. But now there is another concern.
Ms. Babcock said that when ICCAT convenes in the days ahead, they will plot out the management for the coming years. "We hope they will keep the quota low," she said. Ms. Babcock said that all concerned scientists want to do more research on making longlining more selective.
Mr. Rogers said: "We still have concerns with respect to the proportion of juveniles that are being taken." He said fishermen are looking at the use of circle hooks, using different bait and setting nets at different depths.
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