SAVE THE TURTLES!
Written by Gia Mancini
What is the first thing that pops into your head when you think of turtles? Well for me, it’s Crush from Finding Nemo. The way they depict sea turtles makes it hard to believe that people would actually want to harm them, yet humans are their greatest threat. In many traditional cultures, turtles symbolize longevity, endurance and patience. Ironically enough, many turtle species are becoming more and more endangered, especially Chelonia mydas, also known as the Green Sea Turtle.
Description and Location
The beautiful hardy herbivores green sea turtle inhabits warm tropical and subtropical coastal waters around the world. Each population has different colorings and markings in the Atlantic, Indian and Pacific Oceans.1 They have a heart shaped smooth shell, which varies in color, a small head and single clawed flippers which allow them to migrate lengthy distances during mating seasons.2 Being one of the larger turtle species, they can grow up to 4ft in length, and weigh up to 440 pounds.2
Ecology
Unlike most sea turtles, green sea turtles are typically herbivores with a main dish of seaweed and algae. However, they sometimes have an appetite for sea creatures such as jellyfish, comb jellies, crayfish and crabs. Not only are they slow and defenseless on land, which makes them more susceptible to exploitation, but they are also slow in growth rates. As a k-selected species, they have a relatively long age maturity, and it usually takes 20-50 years for sexual maturity.1
Unfortunately, reproduction is no easy or quick task for female turtles.
Mating occurs every 2-4 years and each of them must take a lengthy migration from feeding sites to nesting grounds on beaches. The females leave the ocean at night to lay 100-200 eggs after digging a pit in the sand. Two months later, of the eggs that survive egg harvesters, they hatch and use the light reflected off the water to guid them to the sea. Sadly though, many newly hatched babies don't make it to the sea by the morning and are eventually killed off by predators.3
Listing
Because this species is extremely widespread, their listing of endangerment in the U.S Fish and Wildlife Service is based on population location. Although the estimated population is 85,0000 to 90,000 nesting females there is still a huge concern. These numbers may seem high, but in theory they are small due to the widespread nature of these species. The largest concern are for populations located in the Mediterranean, Central South Pacific, and Central West Pacific. While those three populations are listed as endangered, populations in Southwest Pacific, East Indian West, Central North Pacific, East Pacific, Southwest Indian, South Atlantic, North Atlantic and North Indian are listed as threatened, according to their most current listing status of May 2016. Although majority of these populations are only threatened there is still a huge concern.
As usual, the main threats to these beautiful sea creatures are humans.
Threats and Population Change
Besides by-catch and pollution the two most devastating threats are habitat loss due to human expansion and overexploitation from egg harvesting and hunting. With the growing human population, it is no surprise that urbanization and tourism development on many islands are increasing. Because these turtles need beaches for their nesting sites and exhibit fidelity to their natural beaches, the loss of just part of their habitat can be detrimental to their existence. Not only are they losing their habitats, but individuals are also harvesting their eggs and hunting for meat and other products for international/domestic trade. This is especially problematic in Costa Rica; Despite the fact that turtle egg poaching is illegal, people still continue to participate in it because they have no other way to make a living, or lack suitable nutritional alternatives for the local communities.4 These threats have greatly affected the distribution of breeding sites and many formerly held large breeding colonies have been lost in serval islands such as Bermuda (King, 1982) Cape Verde Islands, and the Cayman Islands (parsons 1962).
Recovery Plan
Thankfully, on January 12th, 1998, a recovery plan for U.S. Pacific populations of the Green Turtle prepared by the Pacific Sea Turtle Recovery Team was created. Their goal is to delist the species and stabilize the population with the help of legislation. By increasing regulation and providing more protection they are hoping to eliminate habitat destruction and hunting so that nesting numbers increase. Some laws that were implemented included, the prohibition of exported sea turtle products to the US, and protection of sea turtle eggs, hatchlings and nesting adults on all Palauan beaches.5 In addition many places in Guam, Republic of Palau, and America Samoa have placed ares under protection. For example, US national park established a new national park in America Samoa with three units to protect beaches and coral reefs. One other way they have tried to reduce habitat destruction is through coastal zone management by giving a limited amount of permits for development in nearshore coastal waters.5
The most recent review for this recovery plan was in 2007. The committee has been measuring the populations progress based on annual number of nesting females and deposited nests at each site. They observed sites in the Western Atlantic Ocean, Central Atlantic Ocean, Mediterranean Sea, Western Indian Ocean, Northern Indian Ocean, Eastern Indian Ocean, Western Pacific Ocean, Central Pacific Ocean, and lastly, the Eastern Pacific Ocean. Of the 23 threatened populations that they were able to access data from,10 nesting populations are increasing, 9 are stable and 4 are still decreasing. Despite this positive trend, we must still look at this data with caution because there was only data available for a little over half of the populations examined.6 Overall, nesting population are doing well in the Pacific, Western Atlantic, and Central Atlantic Ocean, however are not doing well in Southeast Asia, Eastern Indian Ocean, and the Mediterranean.
What can you do?
There seems to be hope for the Green Sea Turtle after all, however we aren't out of the woods yet. There are still many people who find a way to exploit these creatures and disturb their habitats despite the laws and regulations. It is hard to physically protect these species fi you don't live in an area where they breed, so one thing you can do is inform and educate other people about their endangerment. The more people are aware of the threats posed to these turtles the quicker we can combat those threats and preserve the species before it is too late.
Work Cited:
1) Society, National Geographic. “Green Turtles, Green Turtle Pictures, Green Turtle Facts - National Geographic.” National Geographic, animals.nationalgeographic.com/animals/reptiles/green-turtle/.
2) Service, U.S. Fish and Wildlife. “Species Profile for Green Sea Turtle (Chelonia Mydas).” Species Profile for Green Sea Turtle (Chelonia Mydas), ecos.fws.gov/ecp0/profile/speciesProfile?sId=6199.
3) “Green Sea Turtles, Chelonia Mydas.” MarineBio.org, marinebio.org/species.asp?id=51.
4) Main, Douglas. “Costa Rica Has a Sea Turtle Egg-Poaching Problem.” LiveScience, TechMedia Network, www.livescience.com/34514-costa-rica-turtle-egg-poaching.html.
5) Recovery Plan for U.S. Pacific Populations of the Green Turtle (Chelonia Mydas). Silver Spring, MD, U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, 1998.
6) Reen. “Green Sea Turtle 5 Year Review.” US Fish and Wildlife Service .
Pictures without URL next to them are from: (http://evsmersinturtles.blogspot.com/p/about-chelonia-mydas.html
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