Kemp’s ridley ( Lepidochelys kempii )

Kemp’s ridleys are the smallest and most endangered sea turtle species in the world. They grow to be around 2 feet in length and weigh about 80-100 pounds. If you look at a Kemp’s ridley shell, you’ll see that it’s mostly circular and kind of a muddy brown color. This helps them camouflage on the muddy bottom of the ocean, which is where their favorite foods – clams, scallops, shrimp and squid – live.  The beak (sea turtles don’t have teeth; this is what they use to help them chew!) of a Kemp’s ridley is very pointy and hooked.  Since most of the things they eat have 2 shells, these turtles use that hook to pry open the shells so they can eat the meat out from inside.

Kemp’s ridleys are unique when it comes to their nesting behavior: instead of nesting one by one at night like all the other species, these turtles come up in masses called arribadas (which means “arrival” in Spanish) during the daytime. This is when hundreds, and sometimes thousands, of females come out of the water to nest all at once. In one day in 1942, an estimated 42,000 females nested on Rancho Nuevo in one day, but several years later, in the 1980′s, there were no more than 600 females that nested that entire season. Recent good news is that the nesting at Rancho Nuevo seems to be increasing with over 7,100 nests recorded in 2004! Also, unlike the other species of sea turtles who nest on beaches around the world, the Kemp’s ridleys nest mostly on one beach in Rancho Nuevo, Mexico, but they are starting to nest in other areas along the Gulf coast.

Hawksbill ( Eretmochelys imbricata )

Hawksbill sea turtles are the next smallest and usually around 2-2.5 feet in length and weigh 100-150 pounds. These turtles live in coral reefs.  They have very pretty shells that help them camouflage in the corals when the sun reflects and shines through them. Hawksbills have been hunted to near extinction for their pretty shells, which are used to make jewelry and other items.

If you look at a hawksbill’s face, you’ll be able to see how they get their name: from the hawk-like beak they have. It’s long and narrow, much like a hawk’s bill. Hawksbills love to eat sponges. They need this long and narrow beak to help them eat the sponges and reach the small organisms that live inside the sponges. Some of the sponges that hawksbills eat are poisonous, so if a human were to eat the meat of one of these turtles they could get very sick.  Also, inside sponges are things call spicules, which provide structural support for the sponge, or the sponge skeleton.  These are very sharp, and if their meat is eaten, they can cut up our insides like a piece of glass.

Loggerhead ( Caretta caretta )

The loggerhead sea turtles are the most commonly seen in here Georgia’s waters. They are about 3-3.5 feet long and weigh 200-400 pounds. A loggerhead sea turtles favorite foods are blue crabs, sea snails and horseshoe crabs, all things that live on the ocean floor. To help them blend in with their surroundings, their shells are a brownish-orange color.

Loggerhead sea turtles are known to have 80 – 100 different types of epibiota (living organisims-things like barnacles, leeches, crabs and algae) living on top of their shells.  This is also a form of camouflage. These things help them to look more like a rock rather than a sea turtle.  It’s a good way to confuse their predators!

Loggerhead sea turtles are also known for their very large head.  Since these turtles eat a lot of animals with hard shells, they need to have very powerful jaws to crush through those hard shells.  Their beaks (remember, sea turtles don’t have teeth!) are designed to crush and grind through the shells of their food.

Green Turtle ( Chelonia mydas )

The green sea turtles are the largest of the hard-shelled sea turtles, and the second largest overall. They are 4-4.5 feet long and weigh 300-500 pounds. Even though they do not look very green on the outside, they are green on the inside.  This is why green sea turtles are called green sea turtles. Green sea turtles are herbivores, so they eat mostly sea grass and algae. The chlorophyll (the part that makes plants green) builds up in their body over time and dyes their inside fats green.

Unlike the loggerheads who need very large heads to house powerful crushing jaw muscles, the green sea turtles have very small heads.  If you look at the beak of a green sea turtle, you’ll see that it looks like they have teeth, but those are really little serrations that help them rip and tear the sea grasses that they eat.  The shell of a green sea turtle is also pretty like a hawksbills, but they’re a little different.  At the base of the scutes (sea turtle scales-the individual segments) on their shells they have a sunburst pattern.  This sunburst pattern helps them to camouflage with the sea grass beds that they usually hide in.

Leatherback ( Dermochelys coriacea )

Leatherback sea turtles are the largest sea turtle, as well as the deepest diving reptile in the world. They get to be 9-12 feet and can weigh 2,000 pounds. That’s about the same size and weight as a small car! Leatherbacks love to eat sea jellies (jellyfish).

As their name suggests, they have a tough, leathery skin for a “shell” instead of a hard shell. They have this type of shell because leatherback sea turtles can dive up to 4,000 feet underwater.  That’s almost a mile underwater! If they had a hard shell like all the other types of sea turtles, it would crack under the pressure from diving so deep.  If you look at the shell, you’d be able to see the 7 ridges they have going down their back.  Since their shell isn’t made out of bone like the shells of other sea turtles, these ridges help provide structure for the shell.  They are called osteoderms, which are little pieces of bone.  Crocodiles and alligators have them as well.

The beak of a leatherback is designed to pierce and puncture the soft bodies of the jellyfish they eat.  All sea turtles have little thorns called esophageal papillae that line their throat.  These papillae help them hold onto their food in their mouth so they can spit salt water out of their noses.  The leatherback sea turtles are the only species of sea turtle that have these in their mouth.

Even though the leatherback sea  turtle is a reptile (cold-blooded animals, not able to regulate their body temperature), they are the only reptile that can somewhat regulate their body temperature.  Since leatherbacks dive so deep and are seen as far north as the Artic Circle, they need to be able to keep their organs warm.  Leatherback sea turtles have counter-current heat exchange with their blood.  This is where the blood vessels lie very close together, so the blood leaving the core (the middle) of their body can warm up the blood returning to the heart.  They need this to keep their important organs, like their heart and lungs, warm.