The green sea turtle (Chelonia mydas) is one of the two species of sea turtles usually seen in El Nido (the hawksbill sea turtle is the other). It gets its name from the green color of its body fat – the body fat is green because it feeds on seagrass and seaweed as an adult. The green sea turtle is the only herbivorous sea turtle in adulthood. When diving, a green sea turtle can stay underwater for as long as 5 hours because its heart beats only once every nine minutes.
Adult green sea turtles can weigh between 135-160 kg and measure 1 meter long along the carapace (the top shell). If you spot a sea turtle while snorkeling or diving, you can tell it’s a green sea turtle based on it’s carapace: it’s smooth, oval-shaped, and brown or yellow-greenish in color. If you’re close enough to take a look at the head, a green sea turtle has a pair of prefrontal scales (scales on the top of the head before the eyes).
Did you know that female green sea turtles return to the beach where they hatched to lay their own eggs? True story! They mature at 20-50 years old and return to their natal beaches every 2-4 years to lay their eggs. The eggs hatch after 60 days, with the hatchlings heading out to the open ocean where they hide and feed in floating seaweeds for several years. Once they reach a certain age or size range, they move to the coastal areas and start feeding on seagrass and seaweed. Because of their diet, green sea turtles generally stay in shallow, sheltered areas in reefs, bays, and inlets. Green sea turtles are distributed worldwide in tropical and subtropical coastal waters (between 30° North and 30° South).
References:
NOAA Fishers, Office of Protected Resources. Green sea turtle (Chelonia mydas)
US Fish & Wildlife Service, North Florida Ecological Services Office. Factsheet on Green Sea Turtle
Related articles
- My Turtle Tracking Tour adventures (elnidoenvironment.wordpress.com)
Ten Knots Group Environment and Sustainability 
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