Illegal Harvest an Increasing Threat for Tortuguero Green Turtles

Spring 1997 Issue Articles:

* Illegal Harvest an Increasing Threat for Tortuguero Green Turtles

Next Issue
Previous Issue


Illegal Harvest an Increasing Threat for Tortuguero Green Turtles

By Sue Ellen Smith

Illegal sea turtle harvesting be on the rise in Tortuguero, Costa Rica, according to accounts from scientists and research assistants responsible for collecting data during Caribbean Conservation Corporation’s 1996 Green Turtle Program.

In the last few years, it was all too common for researchers and program participants to come back from tagging during the nesting season with stories of possible illegal turtle harvesting. However, turtle hunter activity may have escalated in 1996.

“At its worst three or four nights a week, someone would have a story about illegal harvesting,” said Kristin Caruso, a 1996 research assistant who is now on staff with the Florida Marine Research Institute.

Frequently, researchers and participants came up on evidence of illegal turtle harvesting. On a few instances, research assistants found turtles that had been flipped on their backs so that turtle hunters could pick them up later. When discovered, the turtles were turned back over by research assistants, and watched until they safely returned to the ocean.

Turtle hunters even tried to fool researchers by making fake return turtle tracks in the sand so that it appeared a turtle had come up on the beach, nested, and returned to the ocean, when in fact it had been snatched from its nesting site and dragged through the forest. These incidents, reminiscent of turtle hunter activities in the 1960s when Costa Rica was trying to enforce new turtle protection laws, suggest that illegal harvesting is on the rise.

Many times researchers discovered long pieces of bamboo or logs stuck in the sand that were marking turtle nests so that turtle hunters could find the nests in the daylight and remove the freshly laid eggs. In other instances they found evidence of sticks being pushed through the sand in attempts to find egg chambers.

“It was so obvious that along with turtles, eggs were being illegal harvested as well,” Caruso said.

Tortuguero Village, which has traditionally relied on turtle meat and eggs for food, can get a permit to take a few turtles every month. Researchers do not know if the turtles taken over the legal limit remained in the village or were shipped elsewhere. The curse of being a delicious and easily taken food source has nearly driven green turtles to extinction, which is why the species is now protected in many countries. The penalties for illegal harvesting are not strictly enforced in Tortuguero and do little to discourage repeat offenders.

The increased illegal harvesting at Tortuguero is particularly bad news to scientists and turtle conservationists because the Tortuguero green turtle population is also being affected by the harvesting of green turtles over the legal limit in Limon and higher illegal harvesting along the Miskito Coast in Nicaragua.

Because CCC is a scientific organization, it has no enforcement authority in Tortuguero to stop illegal harvesting. Researchers rely on the Tortuguero park rangers to enforce illegal harvesting laws. However, last year CCC researchers and park rangers did devise a system for signaling illegal harvesting trouble using flashlights. The system worked a few times, but was generally ineffective due to the length of the beach and too few rangers. CCC hopes to provide researchers with radios for the 1997 Green Turtle Program, which starts in July, to improve communication between researchers on the beach and park rangers and increase the response time of rangers to trouble spots.

Probably the best way to turn the tide on turtle hunters would be for the Costa Rican government to hire more rangers to patrol the beach during nesting season. Last year there were usually only two rangers on the beach at any one time. With more rangers on duty, researchers believe, the beaches would be patrolled adequately and turtle hunters would have a more difficult time. Unfortunately, the Costa Rican government’s budget for park personnel is inadequate. CCC is looking into the problem and hopes to be able to provide some solutions.

1996 Green Turtle Program report finished

Researchers tagged 1,395 new turtles during CCC’s 1996 Green Turtle Program in Tortuguero and observed 315 turtles tagged in previous years, completing the 41st year of monitoring. CCC recently released the program’s 1996 final report, which was produced by Research Coordinator Dr. Roldán Valverde.

Five-mile and 22-mile track surveys were a component of last year’s program. Five-mile surveys were concentrated on the northernmost section of the beach, while 22-mile surveys included the entire beach. A total of 4,407 turtle tracks were recorded during the season last year. Of these, 50% corresponded to successful nesting whereas the rest appeared to be unsuccessful. The 22-mile track surveys found a total of 11,297 tracks during the season, with 46% corresponding to successful nesting and the remainder to unsuccessful nesting.

New database interface useful for 1996 program

A new database interface created by Dr. Valverde and programmer Mark Babbe proved to be an important research tool during CCC’s 1996 Green Turtle Program. Dr. Valverde used the interface to demonstrate that artificial lighting from Tortuguero Village is not responsible for the consistently low nesting numbers observed in front of the village. Dr. Valverde was able to generate graphs to show that turtle nesting has been low in that area since well before electricity was introduced to Tortuguero suggesting that the current low nesting is not caused by artificial lighting. These findings also demonstrate that tourism is not the cause of depressed nesting near the village because the phenomenon of low nesting can be seen in the data since before tourists began regularly visiting Tortuguero. The most likely explanation for the low nesting numbers is that villagers have harvested turtles there for many years. Dr. Valverde suggested further studies be conducted so that recommendations can be made to manage the area in front of the village as well as other areas on the beach where commercial lodges or other developments have been placed.

Another important benefit of the new database interface was that for the first time CCC scientists could easily and quickly share their research findings with Tortuguero Park officials, a breakthrough that will prove invaluable to CCC’s conservation efforts.

Interested in CCC’s Green Turtle Program? Visit CCC’s Participant Research Programs or call CCC at 1-800-678-7853 for more information.