Leatherback sea turtles are the largest species of marine turtle and the only one to lack a hard shell made of scales.
Instead, these gentle giants have a softer shell made of bone and skin with seven ridges along their backs. Also unlike other sea turtles, leatherbacks do not have claws on their front flippers.
Even more unusual is that leatherbacks, unlike most reptiles, have some control over their body temperatures, making them warm-blooded. They have a thick layer of fat under their skin and a special blood supply system in their shoulders that can keep them warmer than the water around them, which means they can live both further away from the tropics and in deeper waters than other sea turtles.
Leatherback sea turtles eat mostly jellyfish, and are equipped with special spikes in their throats to keep the slimy creatures from escaping. Their jellyfish-heavy diet probably contributes to reports of leatherback turtle flesh sometimes being toxic to humans.
Like other sea turtles, leatherback turtles lay their eggs on sandy beaches, however, about 20% are “vanos,” or small, yolkless eggs that will never hatch. All the eggs in a clutch are either masculine or feminine—do you know what determines the gender of the eggs? It’s this week’s trivia question on Twitter, so if you live in the US answer now for your chance to win!
Leatherback sea turtles are classified as critically endangered by the IUCN. Threats include being entangled in fishing gear; human collection of eggs and hunting of adult turtles for meat and shell; ingestion of plastic bags, which they mistake for jellyfish; and the effects of climate change on nesting behavior and success. Atlantic populations are considered slightly healthier than Pacific populations, which have seen several important collapses since scientists began tracking sea turtles.
Oceana’s sea turtle campaign focuses on preventing sea turtle bycatch, protecting habitat, and promoting legislation that keeps turtles safe.
You can learn more about leatherback sea turtles from Oceana’s marine wildlife encyclopedia.
Last week the U.S. government issued bittersweet news for loggerhead sea turtles.
First, the good news: After almost four years of debate, the government decided to upgrade Pacific loggerhead sea turtles to “endangered” from “threatened” under the Endangered Species Act. The bad news is that Atlantic loggerhead turtles will still be considered “threatened,” despite the recommendations of the government’s own scientists.
Loggerheads have declined by at least 80 percent in the North Pacific and could become functionally or ecologically extinct by the mid-21st century if additional protections are not put into place. Meanwhile, Florida beaches, which host the largest nesting population of loggerheads in the Northwest Atlantic, have seen more than a 25 percent decline in nesting since 1998.
In 2009, a team of government scientists published a report that classified both populations of loggerhead turtles as “currently at risk of extinction.” In other words, the government dismissed its own scientists’ conclusions about Northwest Atlantic loggerheads.
The government’s review of loggerhead status was prompted in 2007 by petitions from Oceana, the Center for Biological Diversity and the Turtle Island Restoration Network, which asked the government to enforce stronger protections for loggerheads and their habitats.
Unfortunately, the government has also postponed measures that would establish critical loggerhead habitats, an important step in achieving improved protections for key nesting beaches and migratory and feeding areas in the ocean.
We’re making progress, but as you can see, there’s still a long way to go. We’ll continue working to protect sea turtles – and you can help. Tell your representative to save sea turtles from extinction.