Sea Turtles of Okinawa
© Hazel Cruzado
Sea Turtle Identification
Green Sea Turtle
The green sea turtle is the most common species in Okinawa, they have a small head, with 4 lateral scutes and 5 central scutes that are of similar size, usually shiny with sunburst patterns, and they have 1 pair of prefrontal scales.
4 lateral scutes & 5 central scutes
Sunburst / radiating pattern on scutes on carapace
The lateral scutes of the carapace are nearly the same size as the central scutes.
One pair prefrontal scales (scales between eyes)
Small head & round eyes
Rounded mouth area
Dorsal Skull
Ventral Skull
Lateral Skull
Mouth: Greens sea turtles have a beak with finely serrated edges, like the teeth of a saw, which enable them to tear seagrasses and scrape algae off of hard surfaces.
Flipper: One claw on front flipper
As hatchlings Green Sea Turtles are omnivores, but as adults they are herbivores, similar to many other reptiles. Adult diet consists primarily of algae, seagrasses, and seaweed. They have a finely serrated (sawlike) beak that allows them to scrape algae off rocks and tear grasses and seaweeds.
Loggerhead Sea Turtle
The loggerhead sea turtle comes to Japan only to nest, so they are not as commonly seen as green sea turtles. They have a big head, with 5 lateral and 5 central scutes, and often have barnacles adhered to their carapace.
5 lateral scutes
5 central scutes
Reddish brown carapace, often with barnacles adhere onto it
More than one pair prefrontal scales
Big, fat head
Dorsal Skull
Ventral Skull
Mouth: Loggerhead Sea Turtles have strong, big jaws that enable them to crush hard-shelled prey like conchs and whelks.
Flippers: Two claws on front flipper
Adult Loggerhead Sea Turtles are carnivorous, eating crabs, conchs, whelks, and horseshoe crabs. Hatchlings are omnivorous, eating both plant and animal material. They have a massive head and strong jaws which enable them to crush hard-shelled prey.
Hawksbill Sea Turtle
Hawksbill sea turtles are encountered every once in a while in Okinawa, more often on the smaller islands like Zamami. The central scutes are imbricated (overlapped) and the beak is “hooked”
4 lateral scutes
5 central scutes
Central scutes on carapace overlapping
The rear edge of the carapace is deeply serrated.
Thick carapace scutes, with streaks of brown and black on an amber background
Two pairs of prefrontal scales
Small, narrow head that tapers to a distinct hooked beak
Dorsal Skull
Ventral Skull
Often referred to as spongivores because of their specialized diet which consists almost exclusively of sponges. The hawksbill has a sharp, narrow “bird-like” beak that allows them to reach within crevices on the reef.