Why Female Loggerhead Sea Turtles Always Return to Their Place of Birth
Marine turtles are among the most endangered species of the world ocean. For a better protection of these fascinating animals, scientists try to understand why turtles return to their birthplace in order to reproduce after rather long distance migrations. Using molecular tools applied to turtles from the Cape Verde islands, scientists from GEOMAR Helmholtz Centre for Ocean Research Kiel (Germany) found that males and females adopt different strategies: while females are very faithful to their island of birth, males appear less selective and mate at multiple locations.
Furthermore, the study published now in the Proceedings of the Royal Society B: Biological Sciences demonstrates that females from different islands have different immune genes, suggesting that returning home to reproduce is linked to advantages in parasite resistance. This is the first evidence ever to explain why many migratory animals show this type of behavior.
At midnight, a 35-year-old female loggerhead sea turtle (Caretta caretta) crawls out of the ocean and onto the beach. Right, left…right, left, she moves her rear legs to scoop a flaskshaped hole, and lays her very first nest of just over 100 eggs at the Back Bay National Wildlife Refuge in Virginia Beach.
Virginia is at the northern range of sea turtle nesting habitat. Since a sea turtle nest is an unusual find for Back Bay, biologists take the opportunity to meticulously record data from each one. Just a few examples of their data include the length and width of the female’s crawl prints, dimensions of the body pit she created while laying the eggs, and the distance between the nest and the dunes. This, in part, provides information on the age and type of sea turtle that laid the nest. Refuge biologists share their data with partners across the southeastern coast…
Here a close-up shot of a loggerhead turtle (Caretta caretta) in the Gulf of Mexico’s Flower Garden Banks National Marine Sanctuary, which is about 100 miles (179 kilometers) off the Louisiana coast.
Two new studies are showing the turtles are being contaminated with so-called persistent organic pollutants (POPs), which include banned substances such as DDT and toxaphenes, once used as pesticides; polychlorinated biphenyls (PCBs), once used as insulating fluids; and polybrominated diphenyl ethers (PBDEs), once used as flame retardants.
The studies showed the turtles accumulate more of the contaminant chemicals the farther they travel up the Atlantic coast, suggesting their northern feeding grounds in Florida have higher POP levels. The turtles likely consume the POPs when they eat contaminated prey such as crabs, the researchers said. One of the studies was published online April 20, 2011 in the journal Environmental Toxicology and Chemistry, and the other will be published in a forthcoming issue of that journal.
Of the 207 species of turtle and tortoise alive today, 129 of them are listed by the IUCN as vulnerable, endangered, or critically endangered. That’s an incredibly 62% of species!
The species listed here are only a few of the many critically endangered turtle and tortoise species. They illustrate that though these species wear a suit of armor, they are incredible fragile and in need of protection by humans, from humans…
20 sea turtle nests have so far been found on South Padre Island and Boca Chica Beach! The first nest is estimated to hatch the week of June 9th. For more information about attending a public sea turtle hatchling release…
Kemp’s ridley sea turtles are an endangered species that lives in the Gulf of Mexico.
The only time a sea turtle will come out of the water is to lay eggs or their sick. This sea turtle mama is laying her eggs on South Padre Island. Kemp’s ridley sea turtles are the smallest of the five sea turtles in the Gulf of Mexico.
The U.S. Fish and Wildlife Service partners with an nonprofit organization, Sea Turtle Inc, for the protection of all sea turtles. Majority of the sea turtles that nest on South Padre Island are the Kemp’s ridley.
A rare albino green sea turtle (Chelonia mydas) swims in a tank at the Sea Turtle Reserve Centre in Kosgoda, Sri Lanka. The centre collects turtle eggs from the beaches for hatching before poachers remove them as they are considered a delicacy. Once hatched the small turtles are let free in the sea. (2010)
Green Sea Turtles Use Protected Areas, Study Finds
by Douglas Main
If you protect it, they will use it. Green sea turtles do actually make use of protected areas to nest and feed, according to a study that tracked female turtles that came ashore to lay eggs in Florida’s Dry Tortugas National Park.
Until now, it wasn’t clear where these green sea turtles went after nesting and how much they might use nearby reserves. In this case, the animals spent much of their time in the nearby Florida Keys National Marine Sanctuary eating sea grasses and algae…
Puerto Rico creates an ecological corridor to protect endangered leatherback turtles
by Michael Graham Richard
Leatherback turtles, which are rated “critically endangered” on the IUCN’s Red List, are finally getting a break (at least, let’s hope this helps). After a 15-year fight between developers and conservationists, Puerto Rico’s government has finally decided to side with the greens and create a protected zone on the island’s coast to protect leatherbacks. Named the Northeast Ecological Corridor, the protected area is about 14 sq km (5.4 sq mi).
This will not only help leatherback turtles, but also a huge variety of other species, as the area is home to “more than 860 different types of flora and fauna.” While the developers’ hotels and resorts won’t be built, the area should become a great eco-tourist attraction, and hopefully our children will still be able to see tiny leatherbacks hatch out by the hundreds and begin their arduous journey to the sea…
Help Save the World’s Best Marine Reserve: Cabo Pulmo
Established in 1995, Mexico’s Cabo Pulmo Marine National Park is slightly more than 7,000 hectares of coastal waters in the Gulf of California, offshore from the small village of Cabo Pulmo. The park’s establishment followed a period of determined lobbying by the village’s 100 or so residents, who had become alarmed at overfishing and declines in the area’s marine life. The reserve is no more than 5 kilometers (3 miles) wide and measures just 14 kilometers (almost 9 miles) north to south. And yet its impact on the marine life within it, such as these Devil Rays, has been profound – so much so that researchers have dubbed it “the most successful marine reserve in the world.”…
You can help save one of the oldest living coral reefs in the world with a click of your mouse: http://bit.ly/178KBhG
For 20,000 years, the reef of Cabo Pulmo has provided sanctuary for whale sharks, Pacific manta rays, humpback whales, dolphins and sea turtles, but today this marine reserve and the thriving sea that surrounds it is still under threat from overdevelopment.
Urge North America’s environmental authorities to support strong enforcement and protect the coral reef. Send your message!
Remember our traveling turtle? The young endangered loggerhead is now on exhibit in our Open Sea galleries.
The baby turtle weighs 1 pound, 2.5 ounces and is almost 6 inches long. It made a splash even before it arrived at the Aquarium in late December. Then, Curator Steve Vogel and his rare passenger were bumped from their flight to Monterey from North Carolina. After a day’s delay, the pair received the red-carpet treatment flying back to California on US Airways. The sea turtle stayed by Steve’s side in the cabin, and kept warm inside a carrier lying atop a towel covering a hot water bottle.
We shared details and pictures of the entire trip on social media sites, especially Twitter, via the hashtag #TravelingTurtle. As the journey occurred just before Christmas, many people empathized with travel delays and the desire to just go home.
The turtle is on exhibit by itself for now, but will soon be joined by mohara and French grunt fishes. Together, the tropical community exhibit represents species affected by overfishing. Those species of fishes are caught using a trawl, which indiscriminately scrapes sea floors in pursuit of maybe one or two species. As a result, an average of 10 pounds of “bycatch” – including loggerhead sea turtles – dies in pursuit of one pound of fish. (Recently, significant coastal protections for loggerheads were being implemented.)
The turtle will remain at the Aquarium from six to 24 months, depending on its growth rate. Since it will eventually be released back into the wild, aquarists are taking a “hands-off” approach and not hand-feeding it or spending more time with it than necessary. They’ll continue to keep track of the hatchling’s weight through routine exams. Aquarium staff is unsure if it’s male or female. Even experts can’t tell a sea turtle’s gender until it’s around 10 years old.
The turtle is one of nine hatchlings rescued in early 2012 by colleagues with the North Carolina Aquarium. These turtles didn’t make it back to sea with their nest-mates, and were raised at the aquarium. All nine are on loan to aquariums around the country, where they’ll live for up to two years before they’re returned to North Carolina, tagged and released.
From Whence the Green Sea Turtle Receives its Appelation
Adult green turtles (Chelonia mydas) are herbivores, which means they eat only plants such as seagrasses and algae. This diet is thought to give them their greenish-colored fat, hence the name, the green turtle.
Green turtles primarily use three types of habitat – beaches for nesting, open ocean convergence zones as juveniles, and coastal areas for benthic feeding as adults.
In the U.S. Atlantic and Gulf of Mexico waters, green turtles are found in inshore and nearshore waters from Texas to Massachusetts, the U.S. Virgin Islands, and Puerto Rico. In the eastern North Pacific, green turtles have been sighted from Baja California to southern Alaska, but most commonly are seen south of San Diego. Also, in the central Pacific, green turtles are found around most tropical islands, including the Hawaiian Islands…
The planet’s second-largest population of loggerhead turtles — a species that is endangered in many spots around the world — frequents U.S. beaches, from North Carolina to the Gulf Coast of Florida. And now a decadelong tracking study has revealed surprising new information on the turtles’ travels.
But it turns out loggerhead turtles are the dependable type — the sort of turtle you’d want to bring home to Mom and Dad. Wild thrill-seekers they are not, sticking to their usual migration path time and time again…
The Pacific leatherback turtle’s last population stronghold could disappear within 20 years if conservation efforts aren’t expanded, a new study finds.
Most of the Pacific Ocean’s leatherback turtles, at least 75 percent, lay their eggs at Bird’s Head Peninsula in Papua Barat, Indonesia. The number of leatherback turtle nests at the peninsula’s beaches dropped 78 percent between 1984 and 2011, the study discovered.
“If the decline continues, within 20 years it will be difficult if not impossible for the leatherback to avoid extinction,” Thane Wibbels, a biologist at the University of Alabama at Birmingham (UAB), said in a statement. “That means the number of turtles would be so low that the species could not make a comeback.”…
An albino baby Green Sea Turtle (Chelonia mydas) swims with its siblings in a pond at Khram island, about 19 miles from Pattaya, which is east of Bangkok, on June 17, 2009. Special care is given to about 15,000 green and hawksbill baby turtles hatched and housed at the navy’s conservation center each year. The baby turtles’ shells are strong enough to protect them from various predators at about six months old, at which point the young turtles are released to the sea.