NASSAU, BAHAMAS — When local fisherman Novell Hanna goes out to catch grouper these days, he has one less place to fish. The Bahamas has cordoned off one of the grouper's spawning areas - a first for the Caribbean nation and part of a larger, revolutionary plan that a number of coastal countries are considering.
To save marine life, governments are roping off chunks of the ocean. If the idea catches on, the world will soon see a network of marine reserves - the underwater equivalent of wildlife national parks - spread around the globe.
"[We're] right in the middle of this big revolution," says Jim Bohnsack, research fishery biologist with the National Marine Fishery Service in Miami. "We're putting out fences in the oceans.... We're essentially civilizing the oceans."
Although a few marine reserves have existed for decades - Australia's Great Barrier Reef, for example, and isolated areas off the coasts of New Zealand and the US - only recently have scientists reached a consensus that many more such areas are needed to ensure the long-term sustainability of the oceans. (See related story on Endangered Species Act, page 3.)
The theory is simple. Fish in the protected areas produce millions of eggs, which can drift for miles on currents and eventually restock an entire ocean.
Critics say there's no evidence the theory works where it has been tried. Scientists counter that current reserves cover too small an area - far less than 1 percent of the earth's coastlines - to have a measurable effect. They argue that a fifth of ocean coastlines should eventually be set aside.
A network of reserves moves toward that goal. Last year, the United States created 20 no-take zones in the Florida Keys, and it hopes to establish a new one by 2000. New Zealand has a goal of protecting 10 percent of its coastline.
Marine biologists are also pushing for better enforcement of current reserves. In some nations, the restrictions exist only on paper. Poachers are common.
Threat of extinction
"Until now, people haven't really thought that they could cause biological extinction in the sea," says Callum Roberts, a lecturer in marine ecology at the University of York in Britain. But "we do have to start worrying that species of fish will become extinct."
For example, extensive trawling off the coast of the northeastern United States has pushed the barn-door skate to the brink of extinction, he says. The giant clam has become biologically extinct in several island archipelagoes. If such large and well-known species are endangered, marine biologists argue, then lesser-known fish probably are too.
Biologists say traditional methods of protection, such as fishing bans on particular species, limits on net sizes, and quotas on catches, aren't enough anymore. To ensure that a species survives, it needs a reserve.
Technology has spawned the threat. Improved tracking systems detect more fish. More powerful hydraulic lifts put traps down deeper. Better boats stay out longer because they weather storms more easily.
"It's like cutting down the cherry tree to pick the cherries," says Dr. Bohnsack of the US fishery service.
Here in the Caribbean, for example, the Nassau grouper has all but disappeared from more than half of its traditional range, says Kathleen Sullivan, a marine biologist at the University of Miami. Large populations remain only off the coasts of Belize, Mexico, Cuba, and here in the Bahamas.
And the Bahamian Department of Fisheries worries that even its sizable population could be at risk. It is closing off one of more than a dozen spawning areas in High Cay off Andros Island west of Nassau.
The closure will last only through February, which is the season when the fish spawn. But more regulations are expected once the season ends.
"After that point, we will be able to map out a fisheries management plan, which will obviously allow us to sustain the grouper," says Douglas Murray, the department's assistant fisheries officer.
One plan under discussion: expanding the Bahamas's three small marine reserves into a network of sanctuaries. "We are quite a ways along on that," says Gary Larson, executive director of the Bahamas National Trust, which oversees the national parks. "We are actually starting to draw lines on a map."
Local fishermen, including Mr. Hanna, are taking the changes in stride. "If that happens I will work in a different species of fish," he says.
Reservations about reserves
Other fishermen - particularly recreational fishermen - are warier about the potential for locking up prime fishing locations. "Any time marine waters are removed from public use without good justification, it should be alarming," says Doug Kelly, editor of Sport Fishing Magazine in Winter Park, Fla. "The government's going for a water grab."
Many overfished species - such as redfish, tarpon, Spanish mackerel, and pompano - have recovered in the US through traditional fish-management practices, he points out.
In theory, marine reserves should help fishermen. Fish and fish eggs in the reserve will spill over into adjacent fishing areas, allowing harvest of the excess.
But in practice, it doesn't always turn out that way. In New Zealand, for example, many commercial fishermen say they have seen no spillover even from the oldest reserves.
"There is no proof either way, nor has there been a lot of research in that area," says John Eichelsheim, editor of New Zealand Fisherman magazine, based in Auckland. And "anecdotally there is no evidence that fishing even right outside the reserve is any better than it's ever been."
One of that nation's newest reserves - established in the Poor Knights Islands - had been self-governed for years by recreational fishermen, who allowed catches only on the water's surface. Now, the area is off limits to them, even though divers and other recreational visitors can still visit.
"We just never thought the oceans could be overfished," Bohnsack says. But "we now have the capacity to catch fish faster than nature can produce them, and that means we have to have restraints. It's a hard lesson."