Sea Turtles and Climate Change

The majestic sea turtle is a stunning creature. Many people may know sea turtles from seeing them while snorkeling in Hawaii or from seeing Crush in Finding Nemo. However, there is a lot more to sea turtles than just their beautiful presence. Sea turtles are essential to marine ecosystems. They help preserve the health of seagrass beds and coral reefs which in turn benefit the well being of many other sea creatures such as shrimp, lobster, and tuna (WWF, 2000). They also benefit their ecosystem on the land too. Unhatched sea turtle eggs have lots of nutrients that some beaches lack. This boost in nutrients allows for healthier plant growth and stabilizes dunes. The plant growth allows for a fuller ecosystem with plentiful amounts of herbivores and insects. Also, although sad, sometimes sea turtle eggs serve as food for predators (Wilson et al., n.d.). Sea turtles are nothing new and are ancestors to a group of reptiles that have existed on the planet for over 100 million years!

Currently, the green sea turtle has a wide range. The reptile occupies just about every ocean. Below is a graphic showing the green sea turtle’s range. The dark blue area shows where the green sea turtles most commonly are; the light blue shows areas where they may be but are less common. The red dots show some nesting areas (see Figure 1).

Source: (Green Sea Turtle - Chelonia mydas, n.d.)

Sea turtles can be found all over the world in tropical waters. However, they move into temperate zones come summer time. As the map shows, sea turtle populations are densest near land. This is because that is where they mate and lay their eggs. Over the years, sea turtle’s ranges have not changed much. The sea turtle has been around for a long time and has been established world wide for quite some time (Green Sea Turtle - Chelonia mydas, n.d.). Sadly though, the population of sea turtles world wide has declined by 90% over the past 50 years. Over one hundred years ago, it was estimated that there were around 100 million green sea turtles world wide. Today, there are roughly only 90,000 breeding female green sea turtles, and less than a quarter million total green sea turtles total (NOAA Fisheries, 2000). This number is pushing them closer to endangered numbers.

Threats

Currently, green sea turtles are listed as threatened. However, the green sea turtle po;ulations in the Central South Pacific Ocean and Mediterranean Sea are listed as endangered (ECOS: Species Profile, n.d.). All the green sea turtle populations were listed as threatened or endangered on May 6, 2016 according to the environmental conservation online system.

The green sea turtle is currently threatened for a variety of reasons. First, they are dying as a result of bycatch from fishing gear. This practice kills lots of sea life; sea turtles are definitely affected by it but not as bad as some other sea creatures. Next, they are threatened because of human consumption. Humans, kill them and eat them for their meat. This practice is now illegal though in the U.S.. Their eggs are also eaten by humans as well as various other predators (NOAA Fisheries, 2000). Vessel strikes prove to be another threat. Green sea turtles migrating towards the coast for breeding season are at the greatest risk since they swim in high boat traffic areas. Another human caused threat to green sea turtles in ocean pollution and debris. Turtles commonly get caught in and ingest fatal amounts of plastic. On top of this, many sea turtles die from disease. Fibropapillomatosis is a common disease found in green turtles that causes internal and external tumors (NOAA Fisheries, 2000). These tumors inhibit their ability to swim and feed which can cause death. Out of all these though, the biggest threat to green sea turtles is climate change.

Main Threat: Climate Change

Climate change has significantly reduced the green sea turtle population worldwide in various ways. To begin, climate change causes rising sea levels. This rise can sweep away turtles eggs from the shore. Also, climate change induced storms can destroy and alter beaches. This alteration affects beach resources and erosion and leads to an unsuitable egg hatching area. Climate change also causes shoreline hardening, or armoring -- when this happens eggs cannot hatch (NOAA Fisheries, 2000). On top of that, climate change leads to higher sand temperatures on the beaches which have proved to be lethal for turtle

eggs. Pictured above is a once fit turtle nesting beach which has been hurt from storms/erosion (see cracked turtle eggs). Next, climate change has affected ocean currents. The currents push the turtles into newfound territories giving them little time to adapt. This displacement exposes them to new predators and changes what resources are available to them -- this is very dangerous (NOAA Fisheries, 2000).

Recovery Plan

Currently, there are several recovery plans in place focused on saving this precious species. Since green sea turtles thrive world-wide, efforts are spread out amongst all of their habitats. One place where notable work is being done is in Florida (Endangered Species Recovery Program, 1998). Florida’s Hobe Sound is one of the state’s biggest wildlife refuges.

(Hobe Sound)

This refuge focuses on protecting many endangered species but primarily green sea turtles and loggerhead turtles. Many native birds and plants are protected as a result of the turtle efforts here.

The Partners for Fish and Wildlife program provides financial help to private landowners/firms to further restore natural wetlands and habitats that they may own. If financial help is not necessary they provide guidance and educate the landowners on how they may be affecting the local wildlife and what they can do better to protect endangered species (Endangered Species Recovery Program, 1998). Refuges like Hobe Sound occur all around the world and are the most important thing that can be done to protect turtles. Besides that, there has been a great increase in commercial fishing monitoring because bycatch is a great risk for turtles (NOAA Fisheries, 2000). Last, more and more countries are adopting stricter laws regarding animal poaching and trade. Elephants and rhinos are two prime examples of species who are pushed to the brink of extinction due to poaching. Sea turtles experience this too and as laws continue to get stricter, turtles and their eggs become safer and safer from hunters and poachers.

Take Action!

Are you passionate about green sea turtles or any other endangered species? Well, there are lots of things ordinary people can do. The “A Broader View” group offers lots of fun volunteer programs for conservationists. It may be fun to bundle up a volunteering trip with a Costa Rica vacation! Click below to go to their website where you can learn more about what you can do to get a hands on experience protecting these turtles:

• A Broader View Website

If a service trip is too much for you, donating is always effective! The “Fauna and Flora International” organization is a non-profit that works with conservation. They have a specific fund dedicated to green sea turtles. The link to donate is below:

• Fauna and Flora International

If both of these options are not feasible, that is okay! At the end of the day, conservation starts with humans. Humans are the culprits when it comes to climate change and pollution and those are the two biggest threats to turtles. We can start by reducing our carbon footprint. This helps sea turtles because it reduces the dangerous effects of climate change which are listed above. To do this, we can start by driving more gas-efficient or gasless cars, carpool, turn off the lights, eat less processed food, buy food in bulk, look into getting solar, and many other things. Also, we need to reduce pollution to decrease the chances of trash getting into waterways/oceans and killing turtles. We can do this by using reusable water bottles, bags, and tupperware. If you want to be even more proactive, you can write to local legislation if you live in an area close to sea turtles. You can urge lawmakers to protect beaches for the turtles so that they can thrive.

Works Cited

ECOS: Species Profile. (n.d.). Ecos.fws.gov. https://ecos.fws.gov/ecp/species/6199

Endangered Species Recovery Program. (1998). https://www.fws.gov/endangered/esa-library/pdf/recovery.pdf

Green Sea Turtle - Chelonia mydas. (n.d.). Www.californiaherps.com. http://www.californiaherps.com/turtles/pages/c.mydas.html

NOAA Fisheries. (2000). Green Turtle | NOAA Fisheries. Noaa.gov. https://www.fisheries.noaa.gov/species/green-turtle

Wilson, E., Allison, D., & And Magliocca, M. (n.d.). WHY HEALTHY OCEANS NEED SEA TURTLES: THE IMPORTANCE OF SEA TURTLES TO MARINE ECOSYSTEMS. oceana. https://oceana.org/sites/default/files/reports/Why_Healthy_Oceans_Need_Sea_Turtles.pdf

WWF. (2000). Sea Turtle | Species | WWF. World Wildlife Fund. https://www.worldwildlife.org/species/sea-turtle