Changes in Ant Species Distribution on Sea Turtle Nesting Beaches in St Croix, US Virgin Islands

Invasive predaceous ants can cause chaos in their new habitats by competing for resources, increasing or decreasing preys or predators, and even threatening the next generation of offsprings. The red imported fire ant RIFA, Solenopsis invicta is a generalist, omnivorous exotic ant from South America. It has been causing ecological, agricultural, and economical havoc in the USA and other parts of the world. Solenopsis invicta preys on pipped eggs and hatchlings of ground nesting birds and reptiles and they are also found on sea turtle nesting beaches. We hypothesized that there will be a change in the fire ant species distribution at Sandy Point National Wildlife Refuge SPNWR after the first follow-up survey done in 2010, and at Jack Bay after the baseline study in 2011; both nesting beaches are in St Croix, US Virgin Islands. Baited index cards with tuna were set out for approximately two hours then ants were collected in separate marked bags. They were frozen then preserved in ethanol and finally identified. Solenopsis invicta was the most common exotic species at SPNWR. It was significantly more abundant p0.02 than the other fire ant species, Solenopsis geminata which was more abundant in both the 2010 survey and the baseline survey in 2006 at SPNWR. Neither of the fire ant species was found at Jack Bay. This increase in RIFA can become a serious threat to the next generation of sea turtles if its abundance continues to increase at SPNWR.