Mistaken Identities: Loggerhead vs. Green Sea Turtles

Of the seven species of sea turtle in the world, six are found in the Atlantic. Juvenile and adult green, hawksbill, Kemp's ridley, leatherback and loggerhead sea turtles are visitors to the temperate waters of the mid-Atlantic region during warmer seasons, but that doesn't mean they are seen very often. If you are boating off Maryland's coast or in the Chesapeake Bay from late spring through late fall, though, you have a greater chance of spotting and photographing three of these species based on their respective abundance: loggerhead, Kemp's ridley and green sea turtles. As adults, two of these species can be quite similar in size, so here are a few other ways to determine if you've encountered a loggerhead or green sea turtle.

All sea turtles are protected under the Endangered Species Act; in Maryland, the public is required to keep a minimum distance of 50 yards (about three school bus lengths) from these animals, both on the beach and in the water.

Other Differences

Examining these animals more closely shows a host of details that set these species apart. (Given the distance the public must keep from sea turtles on land and in the water, the following differences are more easily spotted with the help of a camera's zoom feature or with binoculars.)

Diet

Clues to each species' diet can be seen by looking at their heads and jaws. Loggerhead sea turtles have broad heads (hence the name) with well-developed muscles and beaks that have blunt surfaces—perfect for crushing hard-shelled prey. The species is mostly carnivorous, eating very little plant material; adults regularly eat horseshoe crabs, blue crabs and whelks, in addition to softer prey like sea cucumbers and anemones.

Green sea turtles, however, have narrower heads. As they mature, they undergo a shift in diet, no longer eating small crustaceans. They develop a taste for algae or sea grasses instead. The serrated edges of their beaks help them cut, clip and saw through fibrous seagrasses with ease.

Flippers

Claws might not seem useful for animals that live in the ocean, but they allow males to hang onto females during mating. The front and back flippers of loggerheads each have a pair of claws, while those of a green sea turtle only have one.

Facial Scales

Just as the number of costal scutes can help with identifying these majestic turtles, their faces do, too. The scales right behind the turtle's nostrils that cover back to the middle of the eyes are called prefrontal scales. Loggerheads have more prefrontal scales than green sea turtles. If there is a single pair of prefrontal scales, it's a green sea turtle; more than one pair points to a loggerhead.

Protecting Sea Turtles

Humans and human activities have had many negative impacts on sea turtle populations over the years, but through various conservation efforts, some species are rebounding. An effort that's made a larger impact on sea turtles is the turtle exclusion device (TED). TEDs act like large fences within trawl nets, allowing smaller prey to slip further into the net but blocking and redirecting caught sea turtles to an "escape hatch" of sorts. In the U.S., large shrimp and fish trawlers have been required to equip their trawl nets with TEDs since the late 1980s. This has greatly reduced the number of sea turtles caught by accident in the Atlantic's coastal waters in the last few decades.

Rescuing, rehabilitating and releasing these animals can also help bolster their future populations. In Maryland, National Aquarium Animal Rescue responds to reports of stranded marine mammals and sea turtles all over the state's extensive coastline. If you spot a sea turtle on a beach, observe it from a distance, note your location and the time of day, and contact the Aquarium's Stranded Animal Hotline at 410-576-3880.

Fishing gear entanglements, boat strikes and plastic pollution are all threats to sea turtles and common reasons for their stranding. Since these problems have few immediate solutions, rescue operations need long-term financial support. To help, contact your representatives and senators and ask them to pass the Sea Turtle Rescue Assistance Act to give all sea turtles a fighting chance.