13 April 2015

The first day of the field portion of our Biology and Conservation of Sea Turtles class began early on Monday, with everyone catching flights from New Bern airport or RDU first thing in the morning. Some of us barely made the connection in Atlanta, and one of our classmates will be joining us tomorrow (more on her adventure in the next blog!). By noon we had landed in San Juan, Puerto Rico and felt the shift to island time as we waited around for our ride to the ferry that would take us to our final destination in Puerto Rico: Culebra.

Culebra is a small island 17 km east of mainland Puerto Rico. The beaches on the northern coast of Culebra are important nesting habitat for leatherback sea turtles (Dermochelys coriacea), and the Puerto Rican Department of Natural and Environmental Resources (DRNA-PR) conducts surveys to monitor nesting activity on the island. We will be working with the Puerto Rican sea turtle team to help survey the nesting beaches in addition to conducting in-water work with juvenile green turtles (Chelonia mydas) and hawksbills (Eretmochelys imbricata).

We caught the afternoon ferry to Culebra, and everyone either dozed or enjoyed the view. We were greeted by Rolando Soler, who has been working with leatherbacks in Culebra since 1997. He is a native of mainland Puerto Rico who came to Isla Culebra for the first time in 1994. He briefly described the projects in which we will participate over the next few days and gave us a short history of monitoring leatherback nesting on Culebra.

Monitoring leatherback nesting on Culebra’s beaches has revealed an interesting trend (see Diez et al. 2010). In the early 1990s, there were roughly 100 leatherback nests recorded in Culebra each year. Nesting activity increased to over 400 nests per year by the late 1990s, followed by a sharp decline in the early 2000s. Within the past few years, annual nesting recorded in Culebra dipped below 100 nests. However, this decline coincided with an increase in leatherback nesting on the main island of Puerto Rico, and genetic studies have shown that the leatherbacks nesting on both islands are from a single nesting population.

These findings have implications for the conservation of leatherbacks here. Namely, successful conservation efforts for a single leatherback nesting population requires the protection of more than a single nesting beach. Additionally, these findings highlight the importance of considering scale in monitoring efforts. If nesting was not being monitored in Puerto Rico, the change in location of nesting might have appeared to be a dramatic decline in nesting rather than a shift in the utilization of nesting habitat.

After talking with Rolando, we made our way from the ferry docks to our home for the next four days: a building on the DRNA property with beautiful views of Ensenada Honda Bay.

We ended the day with a delicious meal at the Krusty Krab, which came highly recommended by Rolando for the platos Criollos, or local dishes. Rice and beans will be fueling us tomorrow morning when we are searching for sea turtle tracks on Culebra’s nesting beaches!

Diez, C. E., Soler, R., Olivera, G., White, A., Tallevast, T., Young, N., van Dam, R. P. (2010). Caribbean leatherbacks: Results of nesting seasons from 1984-2008 at Culebra Island, Puerto Rico. Marine Turtle Newsletter, 127: 22-23. Retrieved from http://www.seaturtle.org/mtn/archives/mtn127/mtn127p22.shtml