Terry Lilley Critter Of The Week
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People flock to Hawaii to see our plentiful sea turtles. There is nowhere else in the world that has as many sea turtles as Hawaii, and that is because they have been fully protected here for many years.

In most of the Pacific Ocean sea turtles are still consumed for food and are afraid of man, but here in Hawaii they are tame, peaceful, and have little concern for their safety unless they are being chased by a big tiger shark that may want them for dinner.

What very few people don’t know is that we have two completely different species of sea turtles here in Hawaii.

The common green sea turtle is seen everywhere, but the very rare hawksbill turtle is extremely rare. As a marine biologist I have done over 1,000 scuba dives in Hawaii shooting video and I have seen thousands of green sea turtles but only six hawksbill turtles.

The hawksbill got its name from the shape of its beak, as it looks like that of a hawk. The green sea turtle has a short, rounded beak. This is because the hawksbill uses its sharp, pointed beak to reach way back in caves and cracks to feed on sponges, soft corals and colonial sea anemones, whereas the green sea turtle feeds on seaweed that grows on the rocks or sea floor. In Hawaii this seaweed is called limu. The hawksbill’s Hawaiian name, “‘ea,” means “reddish brown,” which is the color of their shells.

The other way you can tell the two turtle species apart is the green sea turtle has a smooth upper shell called the carapace, with smooth edges, whereas the hawksbill has a rough carapace that has sharp edges on the shell. The carapace of a sea turtle is made of individual scales called “scutes.” The scutes on the green sea turtle fit together in a smooth pattern, whereas the hawksbill scutes overlap. The turtle’s upper shell is actually its backbone and ribs that fused together to form the hard covering to protect their soft, inner body.

Both of these turtle species can get large and it is easy to tell males from females. The males have a very large, long tail, and the females have a very short tail. The males also have a concave under shell and the females have a flat under shell. These turtles mate in the water and the male balances on top of the female so it has the concave shell to do so.

Like the green sea turtle, the hawksbill turtle lays her eggs buried in the sand on remote beaches in the winter months. The babies hatch a few months later and climb over the sand back into the sea. The babies live the first five years or so of their life out in the deep sea way away from land feeding on jellyfish. One of the problems facing the sea turtles is they will often eat a floating plastic bag thinking it is a jellyfish, and this can cause them to die. The turtles are also killed from time to time by boat strikes and military activity.

The hawksbill sea turtle is fully protected here in Hawaii under the federal Endangered Species Act. There is thought to be less then 100 adult females left in Hawaii, and part of their difficulty in survival is many of the beaches they use to lay eggs on are now covered in homes and filled with tourists.

Recently on Kauai’s North Shore, due to the road closure caused by the massive 2018 flooding, there have been some successful hawksbill egg hatchings that have not occurred for may years. These turtles need large, uncrowded beaches to survive, just like the monk seals and other sea creatures do.

If you happen to see one of these very special creatures please send me an email at underwater2web@gmail.com and let me know when and where so I can hopefully respond and take some pictures. We have a data bank of hawksbill pictures in Hawaii so we can try to keep track of their movements, breeding and numbers.

You can also see my entire hour-long educational movie about Hawaiian sea turtles on my web at www.underwater2web.com, along with my other educational videos we show in our local schools that are also available to the general public.

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Kauai Marine Biologist Terry Lilley’s underwater pictures and educational videos are aon his website, www.underwater2web.com.