By: Elizabeth Whitman, Florida International University
[dropcap]I[/dropcap]f you’ve ever explored the tidal creek systems of Abaco, you probably noticed that it is a preferred hangout for juvenile green sea turtles. Abundant seagrass food resources and refuge from predators make these creeks attractive to turtles who will remain there for 10-to-20 years while they grow and mature to reproductive age.
We are now investigating what factors affect the habitat use of green sea turtles, and in turn, how green sea turtles are affecting creek ecosystems through grazing on seagrasses. To do so, we set up an exclosure experiment one year ago in the tidal creek systems of the Bight of Old Robinson, Snake Cay, and Hill’s Creek. We are collecting data including assessments of seagrasses and macro algae abundance, seagrass density and seagrass canopy height within each plot. We are also collecting seagrass for growth and nutrient analysis to be done at Florida International University. The results of this study will allow us to identify factors affecting feeding behavior of green turtles such as seagrass nutrient content and food availability within tidal creek habitats.
In addition to food availability, turtle feeding behaviors are also affected by the presence of predators; turtles will avoid areas where they are more likely to encounter sharks. Legal protection of endangered sea turtles in the Bahamas began in 2009 followed by the protection of all shark species (many of which are also threatened with extinction) in 2011. As apex predators, sharks play an important role in marine ecosystems, but it is difficult to assess the impact of protective legislation without first quantifying species abundances. We are now conducting short-term baited camera deployments to survey sharks on Abaco’s reefs. This summer, with the help of volunteers taking us to the outer reefs on their personal boats, we are aiming for 150, 90-minute deployments for a total of 225 hours of video. We also hope to extend these surveys over the next two years to include back reef and lagoon areas. If you are interested in volunteering to take us out to deploy the baited cameras, please contact Friends of the Environment.
Friends of the Environment is a non-profit environmental organizations devoted to preserving Abaco’s fragile environment and working towards a more sustainable future. For more information, visit www.friendsoftheenvironment.org, call (242) 367-2721 or email info@friendsoftheenvironment.org.
