|photo by Kirsten Jones - beautiful shot taken in Boca Raton, FL|
Green Sea Turtles 101:
|Happy Birthday, little green turtle!|
Most of those species are found in Florida waters at some point in their life cycle, and today the focus is one particular species - the green sea turtle (Chelonia mydas). Greens nest here in Florida, and are also found in local waters as juveniles, feeding on plants and grasses. There is even a species known as "turtle grass" (Thalassia testudinum). This last fact is especially cool when you look at the classification of the sea turtle:
Kingdom - Animalia (animals)
Phylum - Chordata (vertebrates)
Order - Testudines
So, the plant is quite literally named after turtles - even in Latin!
Why are they called "green" turtles? Especially as adults, green sea turtles are vegetarians, and just like a flamingo turns pink from eating shrimp, the body fat of these turtles is tinged green from all the plant consumption. Cool. Ew. No... Cool.
Where do they nest? Green sea turtles are found all over the world, partly in fact due to their migration routes that expand for tens of thousands of miles. The "long road home" takes on a whole new meaning as this species, along with all other marine turtles, swim back after nearly 30 years to the original beach of their birth. Florida happens to be a nesting hot spot and considering this species has had some serious downs (endangered status) along with great research and conservation efforts, nesting is back on the rise. While an individual turtles may nest as many as 5 times in one season, that takes such a toll on the animal that she doesn't return to the beach the following year. That means a bi-annual pattern of high and low nesting seasons for greens has developed. Plus, with that really long swim mentioned earlier, just trying to get back every single year to nest would be extremely difficult.
|Green turtle track with a distinct tail drag down the middle|
|Big turtle = BIG PIT|
|The 3 stakes in front of this turtle mark a loggerhead nest laid that same night. The tracks from that nest are still visible.|
How big do greens get? This particular species of turtle can easily grow anywhere from 250 - 400 lbs (110 - 190kg) on average. The largest green turtle documented was 5' long and 870 lbs.
How to identify a green from another species: Green sea turtles are distinct in a few ways. When looking head-on, there is only one pair (i.e. 2 total) scales between the eyes. Most turtle species have two pair in that location.
|The 2 Pre-frontal scales between the eyes are unique to green sea turtles|
|Juvenile Green Turtle - Carapace View|
Turtle canneries went out of business long before sea turtles were added to the endangered species list in 1978. This was due to overfishing practices. Research and conservation efforts have been in full swing almost ever since. The point is humans should take responsibility and always tackle feeding our race while keeping sustainability in mind.
Ouch! (I just twisted my ankle jumping off the soap box)
If there is some burning question you have about greens or any sea turtle species, feel free to ask! I'll be happy to share what I know as fact, or else I will find the right answer for you!
I consider myself lucky to have acquired many wonderful friends and colleagues over the years, and Cody Mott is no exception. I have the honor of bragging that I knew him before completing his Bachelor's and Master's degrees, before his work at Inwater Research, and now even before his marriage to another awesome friend- Rebecca. Cody's Master's thesis focused on one behavioral aspect of the green sea turtle. While all sea turtles must orient themselves to reach the ocean as hatchlings, animals with large migration routes must also be capable of finding their way through a multitude of habitats without getting lost. Cody worked closely with one aspect of green turtles and their ability to find direction using the sun as a compass. Many of the behavioral studies on sea turtles focuses on the green. This is because the general consensus among those working with marine turtles on a regular basis is that the green is the most intelligent among the lot. They are usually the ones trained first in captive settings and personally, I find them the prettiest (sorry, hawksbills). I am also aware that the last fact is completely unrelated, but thought you should know anyway!
|Don't those eyes look intelligent to you?|
CODY R. MOTT and MICHAEL SALMON
Department of Biological Sciences, Florida Atlantic University, Boca Raton, Florida 33431 USA
southeastern coast of Florida. When disturbed, the turtles often flee eastward toward deeper water. We captured turtles at night and recorded their orientation during the next 2 days while they swam tethered inside a large circular outdoor pool and were exposed to the sun. The turtles from 2 reef sites were significantly oriented eastward. After 7–10 days of exposure to a laboratory photocycle advanced by 7 hours, turtles tested in the same pool were significantly oriented westward, the predicted direction if they used the sun for orientation. Westward orientation was unaffected by placing either disc magnets or brass discs of identical mass above the turtles’ heads. These results are consistent with the hypothesis that orientation under clear skies is preferentially based upon solar cues. However, control turtles exposed for 7–10 days to a photocycle advanced by 1 hour were also expected to swim generally eastward, but, for unknown reasons, failed to show significant orientation. Our results therefore support the hypothesis that the sun is used as a compass, but additional experiments will be required to provide definitive evidence.
To learn more about Cody's research, or to acquire the complete paper, contact him directly or contact myself through this blog and I will be happy to help. He now works with a fantastic organization called Inwater Research Group. To learn more about their (and Cody's) current work, check out the website: http://www.inwater.org.
For general facts about sea turtles, to learn more about the conservation and research going on throughout the entire world, I highly recommend the following sites:
http://www.seaturtle.org/ or http://www.conserveturtles.org/ The latter was formerly the Caribbean Conservation Corporation and is most useful when looking into research done in that region of the world. I hope this post has helped you get to know and love one of my favorite species just a little bit more!
Just keep swimming!