Feds underestimate snapper recovery, key scientist says

[TimW Texas]

Research by Alabama scientists suggests that federal regulators may have underestimated the size of the red snapper population due to a longstanding reliance on flawed data collected from commercial fishermen.

For the last several years, federal snapper population estimates have meant tighter and tighter regulation of the Gulf’s most important commercial and recreational fishery, with the 2011 season being the shortest on record.

An estimate of how many fish in the Gulf population are more than 10 years old is critical to the calculations that determine how many pounds of snapper commercial and recreational fishermen are allowed to catch each year. More older fish means a healthier population. Too few older fish means a population is being fished too heavily.

The National Marine Fisheries Service data on the age and size of the snapper population — known as a stock assessment — come from commercial fishing records. The information is fed into a computer model created by the fisheries service. Catch limits are set based on the model’s results.

“All of the NMFS model is driven by the age composition of the population. What the NMFS model wants to see is a lot of fish that are 10 years old, and some that are 15 years old,” said Sean Powers, a Dauphin Island Sea Lab scientist studying the snapper population.

Powers is also the chair of the Scientific and Statistical Committee that reviews the fisheries service model and the data that goes into it, putting him in a unique position to review the federal stock assessment.

Bottom line, what his studies show and what the model predicts don’t agree.

“We are seeing a lot more older fish in the population,” he said. “We are collecting those fish with greater frequency than the model predicts. We see the population recovering and building up those age classes more quickly.”

Powers and a group of Sea Lab researchers are in the third year of a study that compares the effectiveness of different types of fishing gear used by commercial fishermen and researchers in the Gulf. The research has involved catching thousands of snapper on both artificial and natural reefs between Apalachicola, Fla., and the Alabama/Mississippi line.

Powers said the fisheries service model has long relied on catch data from commercial fishermen who typically use bandit gear — short stubby rods equipped with electric reels designed to winch snapper up from the depths as quickly as possible.

“If you only sample the commercial catch, then you are seeing only the fish the commercial fishermen want to catch,” Powers said.

Those fishermen use small hooks and small baits in order to catch 14- to 16-inch red snapper, which bring the highest price at market, he said.

“If we were only using bandit gear, we’d see what NMFS sees,” Powers said. But his group is using different methods, including deploying a mile of fishing line along the seafloor with hundreds of baited hooks.

“We’re catching these older fish,” Powers said. “The commercial guys are using smaller hook sizes and small baits. If we use smaller hooks and use squid instead of mackerel, we catch smaller red snapper. If we up the hook size and use larger bait, we catch larger fish.”

Claudia Friess, a fisheries analyst with the Ocean Conservancy, said the commercial fishing gear does appear to target smaller fish. Other new data sets seem to reflect the same trend toward larger fish seen in the Sea Lab data, Friess said, meaning the snapper population recovery may be ahead of where federal officials believe it is.

Friess also said that, due to the government’s review process, the data used to set catch limits is usually three years old.

Roy Crabtree, in charge of snapper regulations for the fisheries service, said the agency was trying to close the gap between when data is collected and when it is used.

He said population data collected by researchers like Powers — described as “fishery independent data” — are probably more accurate than catch reports from fishermen.

Crabtree said the fisheries service received funding related to the Gulf oil spill that has been used to conduct longline surveys similar to the Sea Lab work.

“The biggest thing we’ve needed to improve the stock assessments is this fishery independent data. We’ve got these now,” Crabtree said. “I hope Sean is right, that the stock is further along than we thought.”

The next step, Crabtree said, is to use the new fishery independent data for a new stock assessment. Officials plan to conduct one in the coming year with a quicker turnaround than in the past. The results would primarily affect the 2013 season, though it is possible some of the preliminary data may be used to justify an increase in the quota for 2012.

Powers said snapper live to be 40 years old. A healthy population will have fish at every age group, all the way up to 40.

“We’re seeing a lot of 10-year-old fish, some 15s and even 19s, but not a lot older. I don’t think it is fully recovered, but I think we are a lot further along that recovery path than the current stock assessment says we are,” Powers said.



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