Predaceous Fire Ants (Hymenoptera: Formicidae) at Sea Turtle (Testudines: Cheloniidae) Nesting Beaches and Hatcheries in El Salvador

Abstract

As in many other parts of the world, in El Salvador, few sea turtle (Testudines: Cheloniidae) eggs develop and hatch in situ on nesting beaches. Instead, conservationists relocate most sea turtle eggs to hatcheries for protection. Hatchery managers incubate the eggs in artificial nests within protected enclosures and then release the hatchling sea turtles into the ocean. We surveyed ants (Hymenoptera: Formicidae) on 2 sea turtle nesting beaches and at 14 sea turtle hatchery sites in El Salvador to evaluate the potential threat of predaceous ant species to sea turtle eggs and hatchlings. Of the ant species we found, only the tropical fire ant, Solenopsis geminata (F.) (Hymenoptera: Formicidae), is a known threat to sea turtle hatchlings. We found S. geminata at 5 of 7 (71%) and 7 of 30 (23%) baits along sea turtle nesting beaches at Las Bocanitas and Las Isletas, respectively, and within the nest enclosures at 7 of 14 (50%) hatchery sites. Given the widespread use of hatcheries for protecting sea turtle eggs worldwide, we believe it is important for hatchery managers to recognize the potential threat that predaceous ants pose to hatchling sea turtles. Hatchery managers may be unknowingly releasing apparently healthy but stung hatchlings to the ocean, only to have the hatchlings soon die from sting-related impairment. Fortunately, because of the small size of the incubation enclosures, controlling ants at hatcheries by using chemicals that have low toxicity to verte brates and that degrade quickly (e.g., hydramethylnon) should be safe, simple, and relatively inexpensive.