loggerhead sea turtle
Oceana, along with the Center for Biological Diversity and the Turtle Island Restoration Network, announced last week that they intend to sue the federal government over its failure to designate critical habitat areas for loggerhead sea turtles in the Atlantic and Pacific Oceans – an action required under the Endangered Species Act but that has not yet been done.
Loggerhead sea turtles currently face threats from commercial fisheries, habitat destruction, and climate change along our coasts and throughout the Gulf of Mexico. Unfortunately population recovery efforts are slow, as turtles are long-lived animals that typically don’t reach sexual maturity until 20-35 years of age.
The designation of critical habitat is expected to help restore plummeting population numbers, as species with identified critical habitat are more than twice as likely to show recovery in overall numbers. The designation of critical habitat will likely protect nesting and foraging grounds that are important to the survival and recovery of these turtles.
In order to designate critical habitat, the federal government must first identify areas that are essential to the survival and recovery of the species. More than 90 percent of the U.S. Atlantic nesting population of loggerheads nests on U.S. beaches along the eastern coast of Florida. Critical habitat designation is vital to the survival and recovery of threatened and endangered species. Every day the government delays means more turtles caught in nets and more habitat areas destroyed without consideration of the impacts on the population.
It’s one of the most miraculous journeys in the natural world: sea turtles travel thousands of miles across the ocean to return to the very beach where they first scuttled into the sea.
There aren’t exactly brightly lit mile markers in the sea, so how they do it? Scientists from the University of North Carolina (my alma mater!) say they have figured it out.
The researchers say that loggerhead sea turtles appear to be able to determine their longitude using the strength and angle of the Earth's magnetic field. Although several species of turtles are known to use magnetic cues to determine latitude, it had never been shown for longitude.
I didn’t realize this, but apparently the most difficult part of open-sea navigation is determining longitude (east-west position.) While human navigators struggled for centuries to figure it out on long-distance voyages, loggerhead hatchlings are naturals as soon as they hit the water.
To carry out the research loggerhead hatchlings were placed in circular water containers and tethered to electronic tracking systems to monitor their swimming direction.
During my turtle trip to Bald Head Island, NC in June, the loggerhead nesting numbers were looking dismal, but it was fairly early in the season, so the folks at the Island Conservancy were hoping things would turn around. It turns out Bald Head had its worst nesting year on record since 1983.
This year's loggerhead nesting numbers are in, and yesterday Oceana announced that this year was one of the worst on record from North Carolina to Florida. In Florida, which accounts for nearly 90 percent of loggerhead nesting in the United States, nesting decreased by more than 15 percent in 2009.