The invasion of the red imported fire ant Solenopsis invicta in small tropical islands has not being well studied. The study made by (Porter, et. al. 1997) reflects that the abundance of this invader in P.R. is higher than in the native region but not as high as in other areas in the United States. Porter just sampled the south of the island, which is dry; this affects soil and colony foundation. Rainfall in the north is higher through the year and probably the abundance of this ant can be as high or higher than in the U.S. because of the following reasons: 1) P.R. has no natural enemies for this ant. 2) Islands have less ant abundance than continents, this favors invaders, 3) P.R. is one of the Caribbean islands with more biological invasions. 4) By being tropical, it allows for all year foraging and there is no winterkill. 5) If this ant came from U.S., then it occurred a second bottleneck effect, but it could arrive from Brazil too or both, therefore there is less genetic diversity. This work wants to expand Porter’s sampling to address this question: Despite all this reasons, if P.R. has less fire ant abundance than U.S., then U.S. high abundance probably lies in climate, land use, control management and or the effect of previous ant invasions.

 
Keywords: Solenopsis invicta, ant invasions, Puerto Rico, abundance, tropics
 
References:
 
Buren , W. F. 1982. Red imported fire ant now in Puerto Rico. Florida Entomol. 65: 188-189.

Porter S.D., D.F. Williams, R.S. Patterson and H.G. Fowler.(1997) Intercontinental differences in the abundance of Solenopsis fire ants (Hymenoptera: Formicidae): escape from natural enemies? Environmental Entomology, 26: 373-384.