Sea Turtle Week is June 16-20, but, hey, you already knew that. To celebrate these wide-ranging swimmers, we take a look at their journey from beach to sea -- and back again. Green turtles (above) are the largest of the hard-shell sea turtles, despite having a small head, and can weigh up to 350 pounds (135-160 kilograms). They can grow to 3 feet in length.30 Days Of The Ocean: Photos
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Every morning during the nesting season for green and loggerhead turtles, ecologists from Israel's Nature and Parks Authority search the Mediterranean coastline for nests. They empty the nests and transplant the fragile eggs to protected hatcheries along the coast. Two months later, removed from man-made obstacles and protected from their natural predators -- crabs, foxes and birds -- the hatchlings enter the sea. Some will return more than 20 years later to the same beach and lay their eggs.PHOTOS: The Surprising World of Sea Squirts
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A loggerhead turtle hatchling races for the Mediterranean Sea after leaving a protected hatchery in Mikhmoret, north of Netanya, Israel.PHOTOS: Sharks, Marine Mammals Hang in Paradise
Once they hit the water, hatchlings must swim quickly to escape near-shore predators. And curious humans.VIDEO: Octopi Have a Brain in Every Tentacle
Although sea turtles live most of their lives in the ocean, adult females must return to beaches to lay their eggs.PHOTOS: Life in Australia's Great Barrier Reef
This map shows the Hawksbill turtles' migration range. The turtles are capable of traveling hundreds to thousands of miles between nesting beaches and foraging areas, which are comparable to migrations of green and loggerhead turtles.NEWS: Strange, Carnivorous Sponge Found In Deep Sea
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Members of the Kuwait Environment Protection Society get ready to release a green sea turtle. The turtle, 45 years old and weighing 150 kilograms, was rescued from a fishing trap and released after undergoing medical attention. A tracking device was fixed on the turtle's back in order to help study the animal's movement in territorial waters.PHOTOS: Life On The Ocean Floor Garbage Patch
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At the Miami Seaquarium, kids get a chance to touch one of two loggerhead sea turtles that are prepared to be released back into the wild at Bill Baggs Cape Florida State Park after undergoing rehabilitation.NEWS: Huge North Sea Plankton Bloom Seen From Space
There are seven worldwide species of sea turtle, with six of those found in the United States. Sea turtles are protected under the Endangered Species Act, due to threats from marine debris, bycatch, destruction of their habitat and boat strikes.PHOTOS: Lost Years Of Sea Turtles Uncovered
Green sea turtles of Florida and the Pacific coast of Mexico are no longer considered “endangered,” US officials said Tuesday, hailing decades of conservation work for saving the long-imperiled creatures.
Breeding populations on the beaches of Florida and the west coast of Mexico are now described as “threatened” and still merit protection under the Endangered Species Act, but do not face an imminent risk of extinction, the US Fish and Wildlife Service said.
In Florida alone, there are some 2,250 nesting females counted on beaches each year, up from only a handful in 1978 when the breeding populations were first listed as endangered, an FWS spokesman said.
As part of the change, the US FWS and the National Oceanic and Atmospheric Administration (NOAA) Fisheries divided green sea turtles (Chelonia mydas)globally into 11 distinct population segments, “allowing for tailored conservation approaches for each population,” the agencies said in a statement.
That leaves three populations of green sea turtles worldwide that are considered endangered and at the highest risk of disappearing from the planet — those that live in the Mediterranean Sea as well as the Central South Pacific and Central West Pacific Ocean.
Most of the world’s populations of green sea turtles are listed as “threatened.”
The changes were initially proposed last year and made final on Tuesday after officials reviewed the scientific data and an outpouring of more than 900 public comments.
“Successful conservation and management efforts developed in Florida and along the Pacific coast of Mexico are a roadmap for further recovery strategies of green turtle populations around the world,” said Eileen Sobeck, assistant NOAA administrator for fisheries.
Sea turtles have long faced a host of threats, from beach development that destroyed their nesting habitat, to pollution, to fishing nets that entangled them.
Successful measures have included protection of nesting beaches, reduction of bycatch in fisheries and prohibitions on the direct harvest of sea turtles, NOAA said.
Officials at NOAA estimate that there are currently 571,220 nesting female green sea turtles around the world.
The largest population, including more than 167,000 females, lives in the North Atlantic.
By contrast, among the endangered populations, between 404 and 992 are believed to live in the Mediterranean, and just over 9,000 in the Central West and Central South Pacific, a spokeswoman for NOAA said.
Challenges remain, including climate change and sea level rise that may erode beach nesting habitat and raise the temperature of sand, which can “result in skewed sex ratios and lethal incubation conditions,” the agencies noted in a 134-page document in the federal register.
Some commenters raised concern about a herpes-related virus called fibropapillomatosis, or FP, which is common among young green sea turtles in warmer waters, and can cause fatal tumors.
“We acknowledge the increasing distribution and incidence of FP, particularly in Florida. The threat is likely to increase” along with human-driven pollution of the shores, the agencies said.
Dangerous fishing gear and boat strikes also kill significant numbers of turtles each year.
“Sea turtles face a lot of threats, from plastic trash they swallow to sea-level rise to getting caught in fishing gear -— even poaching, in some parts of the world,” said Catherine Kilduff of the Center for Biological Diversity.
“The undeniable recovery of most green sea turtle populations creates a hopeful spot in our changing oceans.”