Biological invasions

The tropical fire ant, Solenopsis geminata is a New World species with a wide native
range including South America as well as several Caribbean islands. The red imported
fire ant, Solenopsis invicta is native to parts of South America. Both species are known
for preying on sea turtles’ eggs and hatchlings. The objectives of this thesis research
were to conduct follow-up and baseline ant species distribution surveys on four sea turtle
nesting beaches in St. Croix, U. S. Virgin Islands. Tuna baits were set out at beaches;
specimens were collected, frozen, preserved then identified. Results show that there was
a significant change in the fire ants’ distribution at Sandy Point National Wildlife Refuge
(SPNWR) while none were found at Jack Bay. Fire ants were also present on the other
two baseline surveyed nesting beaches. The displacement of S. geminata by S. invicta
was observed at SPNWR, which also was presumed by previous surveys.

The red imported fire ant, Solenopsis invicta, is a South American native
introduced in Alabama in the early 20th century. This predatory species has rapidly
spread throughout the southeastern US and parts of the West Indies, inflicting great
ecological and economic damage. For example, Solenopsis invicta is known to attack the
eggs and hatchlings of ground nesting birds and reptiles. The ants swarm into the nests
attacking hatchlings and diminishing their chance for survival. My thesis research aimed
to survey the distribution of ants on sea turtle nesting beaches in South Florida and St.
Croix, USVI, and to evaluate the possible threat of Solenopsis invicta and other predatory
ants to sea turtle hatchlings.