Marine Creature of the Month APRIL

So I'd like to do a monthly segment where I focus on one marine creature, #MCotM, and this is it! Ordinarily there will be no waffle up here, I will jump straight into it. So to surprise you all, I have chosen my first #MCotM to be... *drum roll*...

The Green Sea Turtle

Photo by me, taken at Two Oceans Aquarium, Cape Town

Kingdom: Animalia

Class: Reptile

Conservation Status: Endangered (EN)

Found: Tropical/subtropical seas; Atlantic and Indo-Pacific oceans

Diet: Herbivorous*

Size: 5ft*

Weight: 68-190kg*

Habitat: Shallow, coastal waters*

*Average adult

There are two main populations of Green Sea Turtles: in the Atlantic ocean and the Indo-Pacfic ocean. Both populations return to the nesting grounds they were born on, which is known as natal homing (from The Biology of Sea Turtles). Females return to the nests every 2-4 years, while males return every year for the chance to mate. The main nesting ground for the Atlantic populations are found in the Caribbean, with smaller nesting grounds further along the American coastline. Indo-Pacific populations nest in Mexico and Hawaii.

The females lay clutches of eggs, numbering anything from 85 to 200 eggs which are about 45mm in diameter. The clutches are buried in the sand and the mothers swim back to the ocean. The temperature of the nests affect the sex of the turtle. Temperatures of 27°C and below produce males, while temperatures of 31°C and above will procude females. Nests which fluctuate between these temperatures will produce a mixture. The eggs hatch at night, 50-70 days after being laid.

Green Sea Turtles spend the first five years of their life in pelagic waters, which are deep waters. Little is known about how they spend their time here, but they return to the coastal shallow waters afterwards where they will reach sexual maturity in the next 15-45 years. It is estimated that only 1% of Green Sea Turtles reach this age. This is partly due to having more predators while juveniles. Newborns face crabs and birds before they even reach the sea, and then have to contend with small marine creatures. As adults their main predators are sharks and, unfortunately, humans. 

They have a conservation status of Endangered largely because of the effect we have on the sea. Green Sea Turtles will often eat plastic bags, which starves them as the plastic does not digest. The amount of plastic pollution affects more than their diet. They become trapped in plastic rings and get our rubbish lodged in their airways. Climate change forces female to use different beaches due to rising water levels. Coastal developments pollute the waters in which they live. And when we aren't directly affecting their habitats, there are those who poach and illegally trade their eggs! 

© Jordi Chias Pujol / Veolia Environnement Wildlife Photographer of the Year 2010

Fun Facts

• Green Sea Turtles are called Honu in the Hawaiian language and are considered a symbol of good luck and longevity.
• They are called Green Sea Turtles not for the colour of their shell but for colour of its fat.
• They can swim at speeds of 2.5-3km/h (1.6-1.9mph). 
• Their diets change as they mature. As juveniles, their diet is carnivorous. They become omnivorous as they mature until they become strict herbivores as adults.
• In the wild, they live up to 80 years old. 
• They will travel 2,600km (1,600mi) and further to return to the nesting ground they were born on. 

Check out the #MCotM April board!