It's all too clear now that native Atlantic salmon are in trouble, very deep trouble.
A fish prized by anglers and commercial fishermen in the northeastern United States and Canada, the Atlantic wild salmon has been so overexploited and underprotected that its very survival as a wild species is now in doubt. Last fall, U.S. government agencies listed the Gulf of Maine salmon population as "endangered," halting all "takings" of wild salmon in seven Maine rivers and one brook. The fish must now be left undisturbed.
Only 75 to 110 fish are thought to be returning to spawn in the designated rivers, according to George Liles, a spokesman for the National Marine Fisheries Service in Woods Hole, Mass. That low count, along with other clues, shows "that the fishery has been greatly reduced."
The sad result, says Jamie Rappoport Clark, former director of the U.S. Fish and Wildlife Service, is that "less than 10 percent of the fish needed for long-term survival of the wild Atlantic salmon are returning to Maine rivers. Without protection and recovery programs, chances are that this population will die out completely."
For several decades fisheries experts have watched -- and warned -- as populations of the beautiful game fish dwindled inexorably. Now, two U.S. government agencies -- the Fish and Wildlife Service, and the National Marine Fisheries Service -- have decided it's time to list the salmon in Maine rivers as endangered, protecting them from exploitation.
Earlier limits on the salmon "take" did not prevent the decline. For decades the numbers of wild salmon anglers could take in fresh water were regulated by the states. In 1997 the rules were changed to allow only "catch and release" fishing. Then, in 1999, fishing for wild salmon was stopped altogether.
The few fish that still return to their native waters are remnants of the once-large fishery centered on the Gulf of Maine. Their breeding grounds are in the rivers of New England and the Canadian maritime provinces. And their feeding grounds are far at sea, where they became vulnerable to fishermen off the western shores of Greenland.
As adult fish are caught at sea, fewer are left to return and spawn in their natal streams, although the catch at sea is now being limited by international agreement.
Like their cousins in the northern Pacific Ocean, salmon on the East Coast return as adults to their "home" rivers to reproduce. But unlike their West Coast relatives, Atlantic salmon don't necessarily die once they deposit their eggs and milt in their riverbed nests. Some of these mature fish return downstream, feed again in the ocean, and then re-enter their rivers to spawn anew. These second-time returnees are often the big lunkers prized by anglers, some weighing in at more than 30 pounds.
In contrast, the Pacific fish return but once and die almost immediately after spawning in their home waters.
Fisheries experts have long known that the harm being done to the salmon comes not only from fishing. According to Liles, the salmons' home rivers have been changed in ways that make survival and spawning less likely. Water is diverted to support blueberry farms. Dams were built to provide power for factories. And a newer industry, fish farming, is seeding the rivers with nonnative fish, escapees from the aquaculture operations.
There are concerns that the aquaculture fish are interbreeding with the native wild salmon and may edge them out for resources and spawning sites.
Even though the intruders may spawn more successfully than the native salmon, the farmed fish may be less vigorous, less able to survive in the wild, than the native salmon. The result would be fewer fish altogether, in part because the farmed fish were selected for their growth characteristics, not survivability in the wild.
Worse, the escapee fish also might carry diseases that will further reduce the wild salmon population. Of worry are infections such as swim bladder sarcoma virus, infectious salmon anemia and coldwater disease.
The listing of wild Atlantic salmon as an endangered species comes after "a long period of decline," which was exacerbated by the loss of big fish at sea, says John Kocik, a fisheries expert with the federal marine fisheries agency, in Woods Hole.
At sea, "the fisheries now have relatively low quotas" of adult salmon that can be taken, as enforced by the North Atlantic Salmon Conservation Organization, Kocik says. The organization assesses the ocean stock of fish that come from American and Canadian rivers. The Canadians are as interested as the Americans in the health of the Atlantic salmon, Kocik adds, because they've seen similar declines in the wild salmon populations.
According to the National Marine Fisheries Service, listing Atlantic salmon as an endangered species means that no one -- other than marine biologists studying the fish -- is allowed to harass, harm, pursue, trap, capture or collect the fish. Included in the ban are salmon in the so-called "distinct population segment" of the salmon stock that live around the Gulf of Maine.
One salmon study conducted on the Narraguagus River at Millbridge, Maine, was looking specifically at the return of adult fish from the sea and the numbers of juvenile fish produced. Then, starting in 1996 "we began looking at the smolt population going to sea" from the river, Kocik says. "What we're finding is that those fish are not replacing themselves, and we don't know why. They have lower-than-expected survival at sea, and lower freshwater survival. So there are problems at both ends" of the migratory pattern.
What's most disappointing, Kocik adds, is that last year they found that only between 45 and 75 adult fish returned to the eight Maine waterways. So, "we've seen a decline in those stocks since 1991, and it's the first time our composite estimate for those rivers has fallen below 100" adult fish.
"These rivers should have a lot more fish in them than they do now." What it means is that "they are very close to the edge of extinction," Kocik says.
But that doesn't signify that the game is all over.
"We have a lot of tools that we can use to try to restore the fish. And we're going beyond just using hatcheries, to look at habitat and innovative enhancement mechanisms. We've [been] partnering with the aquaculture industry, and they've now taken some of the wild fish we would rear in our hatcheries. They're rearing them up in captivity, through the adult stage, and last fall we released some adult fish directly into the rivers their parents were born in."