Rio Grande Cichlid
As its name implies, the Rio Grande cichlid is a native of the Rio Grande river system in southern Texas and northeastern Mexico, making it the northernmost of all new world cichlids. It became a popular aquarium fish in the 1980s, and began showing up in suburban canals around New Orleans soon after that. It is assumed that pet owners are responsible for multiple releases, and it did not take long for the fish to spread its range throughout the south shore of Lake Pontchartrain. Although the Rio Grande cichlid is a freshwater fish, it has grown tolerant to salinities of at least 5 parts per thousand (sea water is about 35 ppt). Its ability to tolerate salty water means that it will be able to spread throughout aquatic systems all over the estuary where salinities would otherwise act as a natural control. The Rio Grande cichlid is omnivorous, meaning it feeds on plants, insects, and small fishes. This species competes directly and indirectly with sunfish and other natives.
Common Name(s): Rio Grande Cichlid, Rio Grande Perch, Texas Cichlid
Date of Introduction to the United States: 1980s
Place of Origin: Rio Grande system
Method of Introduction: Accidental releases through aquarium trade
Problem(s): Can out-compete native fish, could also pose a threat to aquatic vegetation, and can have parasites harmful to native fish.
Current Range: Areas around the east bank of New Orleans, Louisiana in the Lake Pontchartrain estuary. Not yet found in the Barataria-Terrebonne system.
Control Methods: Mechanical
Source: Center for Bioenvironmental Research at Tulane