BOSTON (AP) – The revival of the yellowtail flounder that dwell along the bottom of Georges Bank was once a success story. Scientists saw such abundance in the once-struggling species that last year fishermen were allowed into previously closed fishing areas to go after it.

Then, the fish disappeared, at least on paper.

Regulators said this year that old estimates were off by 77 percent, leaving fishermen facing more cuts and renewing their criticism of fishery science as nothing but a series of bad guesses.

The biggest complaint by fishermen is they can follow the rules to letter, as they did with yellowtail, only to be later told when new numbers come out that they actually fished too much, so tighter restrictions are needed.

Three years ago, scientists estimated there was 39,000 metric tons of yellowtail old enough to spawn in 2001 – the year current restrictions are based on. This year, the estimate for that group had dropped to 9,000 metric tons, meaning the catch limits were set too high and the industry had overfished the stock, even though they followed the rules.

“How can anything else in the real world function this way, in the rearview mirror? … When does there come a time when you admit you don’t have a clue?” said Vito Giacalone, a Gloucester fishermen and chairman of governmental affairs for the Northeast Seafood Coalition, an industry group.

Federal managers say the science has withstood rigorous scrutiny and, though the yellowtail estimate was way off, its predictions are largely on track.

By its nature, the stock estimates become more accurate over time, said John Boreman, science and research director of the Northeast Fisheries Science Center. He acknowledged that scientists tend to overestimate the amount of fish and underestimate how many would be caught.

But Boreman added that fishermen know that counting fish isn’t an exact science, and they take a risk when they act like it is. The struggling industry has pushed fishery managers to allow them to catch as many fish as the current estimates allow, knowing the estimate could change, he said. Boreman called it “managing right up to the edge.”

“We have to decide how much do we have to back off the edge,” he said. “We need to work together to develop a means by which uncertainty can be factored into the decisions we have to make.”

The science of estimating today’s fish populations is built largely on the past. Scientists have a good idea how many haddock were born in 1970, for example, because they can add up the number of haddock caught over the 20-year life span of that fish, figure in the natural death rate, and come up with a solid total. (The earbone of a fish tells its age much like the rings on a tree.)

These population numbers are combined with the results of the ocean surveys taken annually during the life of the fish to help make current estimates.

Say 600 pounds of 6-year-old haddock were caught by the survey in 1976 and the total population of haddock born that year turned to be 10,000 metric tons. Scientists can make a correlation between the survey data and the known population number, and apply it to the results of future survey trawls.

The population estimates become more certain over time as more fish born in a certain year are caught and recorded. The estimate of 1970 haddock was not as solid in 1974, with just four years of catch numbers behind it, as it was in 1980, with a decade of catch numbers to back it.

The most heated conflicts between regulators and fishermen have traditionally come when population estimates sharply contradict what fishermen see on the water. A mistake scientists made setting the fishing net on the survey boat in 2002, which made the net less efficient, reinforced suspicions by some fishermen that the science was based on bad information.

And when population estimates change as drastically as they did with yellowtail in this year’s survey, some fishermen see a conspiracy to force tougher regulations and drive them off the ocean, which they say would satisfy environmentalists pushing for reduced fishing.

Richard Canastra of the Whaling City Seafood Display Auction in New Bedford said the industry has “zero confidence” in fishery science after the latest stock estimate.

“It almost seems as if they’re just cooking the books,” he said.

Carlos Rafael, who owns 20 fishing boats in New Bedford, said he has no faith regulators will improve the science in time to help the majority of the fleet.

“Are we supposed to believe them?” he said. “No, because they haven’t done anything that makes sense to the industry.”

Federal scientists have increased cooperative research with fishermen in recent years to better incorporate their insights. They’re also replacing the net used on their survey trawls to ensure accurate samplings.

Giacalone said managers need to set catch limits as best they can and give the regulations time to work, even if new information tells a new story.

“Instead, we’re being whipsawed,” he said.

Boreman agreed that managers need to “get away from these knee jerk reactions” whenever new data comes out. He said managers may want to consider an approach similar to what was used in the 1970s and 1980s, when managers figured out how much a stock could be fished, then set limits 10 percent below that level, creating a sort of buffer zone that acknowledged the uncertainty of the estimate.

“There’s always an unpredictability in nature,” Boreman said. “Our job is to eliminate as much uncertainty as we can. We’re moving in that direction, just not fast enough.”

AP-ES-11-05-05 1021EST

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