Though thousands of loggerhead sea turtles, a threatened species under the Endangered Species Act, nest along the Atlantic Coast each year, the National Marine Fisheries Service has not yet designated habitat critical to the species' survival, according to conservation groups planning to sue over that lack of designation.

On Thursday the groups moved to try to force that designation, announcing that they would sue the NMFS and the U.S. Fish and Wildlife Service over the matter. Specifically, the groups want to see critical habitat for loggerheads designated along Florida's nesting beaches and in the Atlantic and Pacific oceans.

Loggerheads nest on the beaches of both Cape Lookout and Cape Hatteras national seashores, and some nesting has been reported as far north as Virginia. The bulk of the nesting in the United States, however, occurs on beaches in Florida, including those at Canaveral National Seashore.

According to the Center for Biological Diversity, "Florida beaches, which host the largest nesting population of loggerheads in the United States, saw nearly a 40 percent decline in nesting since 1998 before minor rebounds in recent years. North Pacific loggerheads, which nest in Japan and cross the Pacific to feed along the coasts of Southern California and Mexico, have declined by at least 80 percent over the past decade."

Without more protection, declines could increase in the years to come, the group maintains.

“With the seas rising and development transforming our coasts and oceans, sea turtles don’t have many safe havens left to nest and feed,” said Catherine Kilduff, an attorney at the Center for Biological Diversity. “To save these amazing turtles, we have to identify and protect the places they live.”

At Oceana, the largest international advocacy group working solely to protect the world’s oceans, Beth Lowell noted that the "Endangered Species Act is a safety net for species like loggerhead sea turtles that are on a path toward extinction. By protecting the regions vital to their well-being, we can help rebuild plummeting sea turtle populations. The government is failing loggerhead sea turtles by delaying the designation of critical habitat.”

Those two groups, along with the Turtle Island Restoration Network, maintain that "critical habitat protection would help safeguard key nesting beaches as well as migratory and feeding areas in the oceans. The designation would also prohibit federal projects that would potentially destroy or harm these areas to ensure the conservation and recovery of imperiled sea turtles. Endangered species that benefit from protected critical habitat are twice as likely to show signs of recovery than those without it."

While the U.S. government identified nine separate populations of loggerhead sea turtles in September 2011 under the Endangered Species Act, since then it has failed to follow through with the requirement that it also designate critical habitat areas for the populations, the groups said in a press release.

"Habitat has not yet been protected; today’s notice of intent to sue the National Marine Fisheries Service and the Fish and Wildlife Service targets that failure," they added.