Swimming With Sea Turtles in the Bahamas
Cape Eleuthera Institute, Eleuthera Island, the Bahamas
Earthwatch Scientists: Annabelle Brooks, Dr. Karen Bjorndal, Dr. Alan Bolten
Thank you for your generous contribution to Earthwatch’s “Swimming With Sea Turtles in the Bahamas” research expedition! The 2014 research season for this project is about to begin, on February 13th, and will operate until November 16th. We look forward to providing you with real-time participation and research updates throughout the year. In the meantime, here’s a brief summary of the research and activities your thoughtful donations are helping to make possible.
In order to save the green sea turtle and the hawksbill sea turtle from further decline, researchers need to ensure their habitats are protected from coastal development. But where exactly are these turtles most likely to be found, and why? With your help, these are the critical questions that Earthwatch scientists and volunteers will try to answer. The data they collect will then help researchers and the government create plans that will protect the right habitats – and the most turtles - from further harm.
The research focuses on five objectives:
- Recording Sea Turtle Abundance and Distribution: Scientists know that shallow waters serve as important feeding grounds for juvenile hawksbill and green sea turtles, but the characteristics of foraging grounds can vary greatly. Plotting the frequency of turtle visits to each site will help researches identify which ones are most popular.
- Mapping Habitat and Food Resource Availability: When compared with sea turtle numbers from the first objective, mapping food resources found in the foraging sites should help researchers understand how green sea turtles and hawksbills choose where to dine.
- Assessing Predation Risk: A suitable habitat is not just rich in food supplies; it’s also free from predators. Researchers hypothesize that areas crowded with predators will have fewer sea turtles.
- Long-Term Monitoring: Turtles travel throughout their lifetime. By tagging and monitoring their movements, scientists can determine what (and where) turtles eat while they grow.
- Determining Fine-Scale Movements: This objective involves tracking individual turtles to understand their daily movements and activities, using tags that transmit the turtle’s location,
Earthwatch scientists and volunteers will work towards these objectives using the following research methods:
- Turtle Abundance Surveys: From a boat, volunteers will spot turtles and record their locations via Global Positioning System (GPS), as well as the time, wind speed, cloud cover and other conditions.
- Habitat Surveys: Volunteers will snorkel through sites where turtles feed to collect sea floor habitat data (e.g., percentage cover of seagrass, algae, and sand) and determine physical characteristics such as depth, temperature, dissolved oxygen content, and mangrove root density. Volunteers will also collect plant tissue samples for chemical analysis and use GPS to identify locations of various sea floor characteristics.
- Tagging Sea Turtles: When a turtle is caught, volunteers will record the data as the scientists measure and weigh it, collect tissue samples, tag it, and finally release it gently back into the water.
- BRUV Work: From a boat, volunteers will bait, deploy, and retrieve Baited Remote Underwater Video units (BRUVs) that record the animals that swim into range.
- Acoustic Telemetry: Volunteers deploy acoustic transmitter tags and acoustic hydrophones either from a boat or while snorkeling. The data from these units will help us understand individual sea turtle movements within their foraging grounds and their habitat preferences.
- Data Management. In the evenings, or during unfavorable weather, volunteers will help with one of the most pivotal steps in any scientific research - entering and analyzing data – by transferring notes from the field into a database and analyzing BRUV video footage.
As you can see, there is a LOT of work to be done this year in the Bahamas in order to gain the knowledge and understanding needed to successfully protect the green sea turtle and hawksbill turtle from further endangerment, and none of it would be possible without the generosity of donors like you. Thank you for your ongoing support of this research!
Director of Annual Giving & Advancement Services
P.S. If you are considering taking the plunge yourself and volunteering on this expedition – which we strongly recommend! - you can learn more about it here: