Green Sea Turtles

A highlight of our recent Hawaii trip was seeing good numbers of Green Sea Turtles (Chelonia mydas). This is the commonest and most wide-ranging of the world's seven sea turtle species, and I've seen them on many prior occasions, but whopping big turtles are always a treat to behold. Following are a few images and some commentary.

A Green Sea Turtle hauled out and basking on a beach. While some beaches on Maui are used as breeding sites, the majority of the Hawaiian population breeds at Papahānaumokuākea Marine National Monument, which is about 900 miles northwest of this spot.

It takes a lot of good fortune for a turtle to live long enough to attain this size. It takes females 20-30 years to reach sexual maturity and begin nesting. Reproductively active females visit breeding beaches - usually the one where it was born, or one nearby - and crawl out at night. She digs a hole in the sand and dumps up to 100 or more eggs in it. They'll create a few nests over a few weeks period and can dump nearly 200 eggs in total. This is reptilian carpet-bombing reproduction. Predation of newly emerged turtlelets is quite high, and most will not make it.

Here's a closer view of the turtle above. Green Sea Turtles are the largest of the sea turtles. Mature specimens can be up to four feet in length and weigh 350 pounds. They are also the most successful species, occurring in warm seas worldwide, and boasting a population estimated at 90,000 breeding females, and presumably a similar number of males.

This was a particularly turtleiferous beach. About 25 turtles or parts thereof are visible in this shot, and there were others off camera. Even though this particular spot was one of the most popular surfing beaches on Maui, people are generally quite respectful of the big reptiles and give them their space.

An adult sea turtle pops its head up for a quick breath. It was surprisingly hard to get this shot, as you never know when they'll surface, and when they do, it's usually only for a few seconds. Whan at rest, a turtle can remain underwater for up to seven hours. When actively feeding, as this one was, surface visits for air are much more frequent but still not that frequent.

This spot was ideal for watching turtles feed, as the water was clear, we were on a cliff not far above the water, and one could often see the reptiles swimming under the water. They were feeding by rasping algae and perhaps various "sea grasses" from rocks, abetted by their rough, semi-toothy or serrated lower mandible.

Big flippers aid the turtles in swimming gracefully, and they are able to agilely dart among rocks, even in crashing surf. Their swimming prowess also aids Green Sea Turtles in their long migrations.

While Green Sea Turtles were once heavily hunted, now they are protected in most areas and have recovered nicely. If you visit Maui, you'll see many of the magnificent animals.