Sea Turtles: The DR’s Serene Swimmers


Sea turtles are so freakin’ cool. While they look beautiful, act peacefully, swim gracefully, and paddle themselves patiently through the sand, sea turtles can sometimes seem like prehistoric creatures straight from Edgar Rice Burroughs’ The Land That Time Forgot (or, if you will, Robert Silverberg’s Hawksbill Station). In fact, they pre-date dinosaurs,  going back 200 million years. Bad news: hawksbill, leatherback, and green sea turtles are endangered; thus, conservation measures are urgent. Good news: your actions at the beach can help.

As mentioned previously in Omar’s post, three species of sea turtles nest on Dominican beaches:

1. Hawksbill Turtles (Eretmochelys imbricata) 

2. Green Sea Turtles (Chelonia mydas)

3. Leatherback Turtles (Dermochelys coriacea)

 

Each of these species will migrate extensively from their birthplace to feeding grounds, experiencing more of the Caribbean than most of us. For example, a Hawksbill was tagged for tracking in 2008 at Jaragua National Park by Grupo Jaragua and seaturtle.org, and over the next four months, it leisurely swam to the coast of Honduras. More recently, “Inspire” was tracked from Nova Scotia (Canada) all the way to our dazzling Bahia de Samana.


 

1. Hawksbill Turtles (Eretmochelys imbricata) 

Hawksbill Turtle Distribution Map

Hawksbill Turtle (Eretmochelys imbricata) Distribution Map

 

With a lifespan up to 50 years, Hawksbills grow to approximately 100 cm (3½ feet) and 70 kg (150 lbs). They feed on algae, seagrass, shellfish and marine sponges. Their nesting period is June-December, and each female produces 150-250 eggs at a time, several times during the season.

Eretmochelys imbricata | Omar Shamir Reynoso

Eretmochelys imbricata | Omar Shamir Reynoso

They have a sharp beak and two claws on each fin. Hawksbill shells have been prized since ancient times (hard, brown and yellow, and covered in plates with serrated edges). Interestingly, young Hawksbills cannot dive deeply and spend their time floating near the surface among sea plants.

Hawksbill Turtles have been classified as Critically Endangered by the IUCN Red List of Threatened Species.

 

Hawksbill


 

2. Green Sea Turtles (Chelonia mydas) 

Green Sea Turtle Distribution Map

Green Sea Turtle (Chelonia mydas) Distribution Map

Chelonia mydas | Omar Shamir Reynoso

Chelonia mydas | Omar Shamir Reynoso

Green Sea Turtle jaws are serrated to help them easily chew seagrass and algae. With a lifespan up to 100 years, Green Sea Turtles grow to 120 cm (4 feet) and 160 kg (350 lbs). Although adults are herbivores, juveniles are omnivores eating a variety of seagrass, insects, worms, and shellfish. Their nesting period is May-September, and each female produces 100-250 eggs at a time, several times during the season.

 

Green-Sea-Turtle

 


 

3. Leatherback Turtles (Dermochelys coriacea)

Leatherback Turtle Distribution Map

Leatherback Turtle (Dermochelys coriacea) Distribution Map

Dermochelys coriacea | Omar Shamir Reynoso

Dermochelys coriacea | Omar Shamir Reynoso

With a long but poorly understood lifespan, Leatherbacks grow to over 2 m (6 feet) and weigh more than 700 kg (1,500 lbs). They feed mainly on jellyfish, and they nest in summer (May-July), with each female producing 80-90 eggs at a time, several times during the season.

These are the largest sea turtles, and are the only sea turtle with a soft shell (hence their name “leatherback”). Leatherbacks can dive to an astounding 1,300 m depth.

Leatherback


Where do they live?

The DR’s main nesting areas are in Jaragua National Park [http://www.beachup.com.do/en/playas/bahia-de-las-aguilas-beach/ — or — http://www.grupojaragua.org.do/pnj_english.html] and on Isla Saona. [http://beachup.com.do/en/playas/playa-isla-saona-1/ — or — https://en.wikipedia.org/wiki/Saona_Island] However, they are in critical condition, and only 30-40 nesting females are seen at each location annually (Tomás et al., 2016). [http://www.britishcheloniagroup.org.uk/testudo/v7/v7n3tomas] Other important nesting beaches include:

  • Catalina Island, Guibia, Los Pescadores, San Souci, Estero Hondo, Punta Cana, and El Valle for Hawksbills and Green Sea Turtles
  • La Vacama, Muerta Beach, Coson, Cabarete, Los Yayales, Manresa Beach, and El Valle for Leatherbacks

Local turtle locations are also mapped by “The State of the World’s Sea Turtles” (SWOT). [http://seamap.env.duke.edu/swot]

 

In addition to the three species that nest in the DR, Loggerhead Turtles (Caretta caretta) — up to 4 ft long and 350 lbs — are being captured offshore near Montecristi, Maria Trinidad Sanchez, and Samana.

 

 

Threats:

Human actions are deeply impacting turtle survival. Primary threats include:

  • Poaching from nesting beaches and feeding grounds: eggs and meat are sold as delicacies and/ or shark bait, and shells for crafts and accessories. Over the past century, millions [http://www.iucnredlist.org/details/8005/0] of Hawksbills have been killed globally for their tortoiseshells.
  • Unintended capture in new and discarded fishing nets, and ship strikes.
  • Habitat degradation of nesting beaches and feeding grounds by:
    • Building construction near beach nests – lights can change a nesting female’s behavior, and will draw hatchlings away from the water, which is fatal.
    • Clearing of dune vegetation for recreation and commercial development, triggering erosion and subsequent dredging and beach re-nourishment.
    • Coral bleaching caused by climate change destroys critical feeding habitats, especially for Hawksbills.
    • Harvest of nearshore ocean life needed to sustain turtles.
    • Marina construction, increased boat traffic and pollution, and disorienting boat lights.
  • Floating plastic and marine debris eaten by turtles.

 

What You Can Do: [hyperlink to popup box 6 (see below)]

Sea turtles are worth more as living wonders than they are when caught in nets or crushed on the road. Thankfully, interest is growing in both sea turtle conservation and ecotourism. Community-based initiatives to reduce poaching and bycatch in the DR are showing promise. Individuals can help by:

  • Proactively looking for beach nesting areas and reporting them to ____ [maybe Widecast? http://www.widecast.org/What/Country/DominicanRepublic/dominicanrepublic.html]
  • Turning off your beachfront property’s lights at night
  • Reporting any signs of poaching, and convince local administrators to enforce existing regulations [maybe hyperlink to a popup box with a list of the 31 provincial governors and their contact info?]
  • Eliminating litter onshore and in the ocean

These few small adjustments in our behavior will make a tremendous difference.

Sea turtles are protected by several international treaties and laws, including:

 

So … if you see one, before you think “those things look so weird when they try to run/ swim through the sand”; before you think “I wonder where this one has been and what part of the Caribbean it will go?”; before you reach for your camera phone; please please please ask yourself “on this trip to the beach, have I helped or harmed our sea turtles?”

Beach Up

Beach Up

Beach lovers, adventurers, believers in the power of information and technology. A team convinced that raising awareness about Dominican beaches is –much- more about endurance than speed.

Comments Talk and discuss with Us