The University of Florida / IFAS - St. Lucie County Cooperative Extension is seeking the assistance of local fishermen to report sightings of "tilapia-sized" fish identified by University of Florida fisheries scientists as jack dempseys ( Rocio octofasciata formerly known as Cichlasoma octofaciatum). Jack dempseys are common aquarium fish that when released from aquariums can reach 10 inches in size or more. Their name refers to the legendary boxer Jack Dempsey because they fight other fish in the aquarium. Sightings have been reported by fisherman fishing in local storm water retention ponds.

Jack dempsies have been reported in freshwater ponds sporadically throughout Florida - probably as escapees from the aquarium trade. Their populations tend to die out over time. University of Florida specialists are interested in monitoring these populations to determine if they have permanently established. Jack dempseys mature from a light gray or tan with pale turquoise flecks to a dark purple-gray with very bright, iridescent blue, green, and gold flecks. Fishermen might mistake these fish as another introduced species: Blue Tilapia.

Fishermen can bring preserved samples on ice to the University of Florida / St. Lucie County Cooperative Extension, 8400 Picos Road, Suite 101, Fort Pierce. Photos and location information can also be sent to Ken Gioeli, Natural Resource Agent, at ktgioeli@ufl.edu. For more information, please call the Extension office at (772) 462-1660.