Federal regulators decided Thursday to cut Florida's longline grouper fleet in half to protect loggerhead turtles.
Longliners, who string miles of hooks along the bottom, catch about two-thirds of the commercial grouper that end up in restaurants and seafood counters.
From time to time, they also catch and kill loggerheads, a protected species whose nests on Florida beaches have dwindled in recent years.
The Gulf of Mexico Fisheries Management Council, which manages federal waters, shut down longlining in June, as an emergency measure, after a report indicated that longliners were killing way more loggerheads than previously thought.
The rules passed Thursday are designed to be permanent, though they will take about six months to implement.
Under the new rules, only the most successful longliners — 61 boats that average at least 40,000 pounds of grouper a year — can continue using that method.
A longline boat can put no more than 750 hooks into the water at one time. Some boats typically used twice that many.
From June through August, longliners must fish in water that is at least 210 feet deep, where turtles might be less likely to forage.
The National Marine Fisheries Service will now conduct a "biological opinion" study required under the Endangered Species Act to determine if these new restrictions are sufficient to protect the turtles.
The effect on the marketplace is uncertain. Demand for grouper has fallen during the recession, plus some longliners are learning how to catch grouper with other methods that are not restricted under the new rules.