June 21, 2009
Controversial New Device Could Save Sea Turtles
In an effort to protect rare sea turtles from being caught and killed in fishing nets, fishery managers have looked to a Cape Cod company to build a device they think can help save the turtles without interfering with fishing profits.
The device is called a "tow-time logger", which is a 7-inch silver cylinder attached to fishing nets to record how long the net is submerged in the water.
That amount of time is absolutely critical if a turtle is captured in the net and dragged behind fishing trawlers. Federal research shows that most sea turtles can survive the entanglement if they are pulled up in in less than 50 minutes.
This device allows regulators to avoid putting more burdensome restrictions on struggling fishermen, such as shutting down fishing areas or requiring turtle-saving gear that is not affective in all nets. Fisheries using time limits would not have to depend on an honor system to make sure the nets are pulled up in time.
"Turtles have also been around since the time of the dinosaurs," said Elizabeth Griffin of the environmental group, Oceana. "They're cool animals that I think most people want to see continue to exist."
The logger was built by Onset Computer Corp., a supplier of data loggers for energy and environmental monitoring under a $25,000 NOAA federal contract. It is designed to begin recording water depth in 30 second intervals once the net drops below 6.5 feet. If the net is not pulled up within the 50 minutes, the device records it and the violation is seen when the regulators download its data.
The device proved to be a success in initial sea tests, and they are working to make it strong enough to rough it in the real world where it will be knocked around on fishing boat decks. The company says the device will likely cost the fishermen between $600 and $800.
Regardless of how perfectly the logger is made, regulators note that under water limits for nets will not fix the problem entirely. They hope to propose a set of rules they devised for public discussion by 2010, to meet a new federal requirement to protect sea turtles from trawler fishing nets.
Lack of oxygen for any length of time can cause great harm to sea turtles, which concerns some environmentalists who say they should not be trapped under water at all.
Griffin says there's also not enough data to show what affect cold water has on the turtles, which means it is unknown whether they can survive at all if kept underwater.
Griffin says that if researchers can determine what is safe, the data logger can at least make shorter tow times a simple way to protect turtles.
Fishermen are less enthusiastic. They don't see short tows as a practical solution in most fisheries such as in deep waters, where a worthwhile catch is impossible when the nets are constantly being pulled up.
"It's a bad idea," said veteran fisherman and head of the North Carolina-based United National Fisherman's Association, James Fletcher.
"Nobody's going to love the idea," acknowledged Henry Milliken, a biologist with the National Marine Fisheries Service, which is part of NOAA. But he says fishermen would probably prefer a limit on net submersion to more severe measures, such as closing fishing areas all together.
"The idea is that we're looking at providing options to the managers in the future," Milliken said.
As the NMFS tries to figure out what does and doesn't work, it has held public meetings from New York to Georgia this spring.
The loggerhead, a 250-pound threatened turtle named for its relatively large head, is one most often trapped in trawl nets in the Atlantic. Every sea turtle in U.S waters is listed as either endangered or threatened, making any turtle deaths in fishing nets detrimental to the population.
The most common method in protecting turtles is the Turtle Excluder Device, which is a circular, barred frame attached near the front of fishing nets. The bars are big enough for fish and other sea life to slip through, but too narrow for turtles, which bounce out of the net before they get caught.
The excluder devices have proven to be successful in some fisheries, including the Southeast's shrimp trawl fishery, but larger species, like the horseshoe crab, monkfish and flounder, can escape along with the turtles and make the nets incredibly inefficient.
Greg DiDomenico of the Garden State Seafood Association, a New Jersey trade group, said says that having the new rules applied to fisheries from Cape Cod to Florida, where the turtles swim, whatever ultimately happens is bound to be felt across the industry. He said this will include "huge negative impacts on some fisheries."
With regulations in the near future, DiDomenico said he just hopes that regulators don't broadly force a one-size fits-all turtle-protecting solution on such a diverse industry.
On the Net: