Occurrence of an Introduced African Cichlid, 



the Blue Tilapia, Tilapia aurea, in a Tidal Creek 



of the Skidaway River, Georgia 



L. Stanton Hales, Jr. 



Department of Zoology and Institute of Ecology 



University of Georgia, Athens, Georgia 30602 



and 



Marine Extension Service Aquarium 



Georgia Sea Grant College Program 



Skidaway Island, P. O. Box 13687 



Savannah, Georgia 31416 



ABSTRACT.— The blue tilapia, Tilapia aurea, has not been reported 

 previously from estuarine waters of Georgia. More than 35 juvenile 

 blue tilapia were collected in a tidal creek on Skidaway Island, 

 Chatham Co. Although it is not possible to determine the exact time 

 and circumstances of the introduction, those specimens escaped from a 

 raceway on Skidaway Island during the summer of 1989. The raceway 

 system has been used for aquaculture experiments since the early 

 1970s, but recent changes in the drainage system (to provide for 

 emergency containment of spills) may facilitate the establishment and 

 spread of this population by warming water to the contained marsh, 

 which enhances overwintering survival of this tropical species. The 

 same traits of blue tilapia that are desirable for aquaculture have 

 enabled the species to establish populations in a diverse range of 

 habitats, including estuaries, in the southeastern United States. 

 Deleterious effects of this species on some native fishes have been 

 reported in Florida and Texas, and it seems prudent to eradicate the 

 local population if possible. 



An extensive review of the status of introduced fishes in the United 

 States (Courtenay et al. 1984) listed the unconfirmed reports of Tilapia 

 aurea (Steindachner) and Tilapia mossambica (Peters) on St. Simons 

 Island and Sea Island (Glynn Co.) as the only reports of cichlid fishes in 

 Georgia. This paper documents the first confirmed report of a cichlid in 

 the state of Georgia. 



Although it now occurs more widely across Africa, the blue tilapia, 

 T. aurea, is native to Senegal; Middle Niger; Benue, Shari and Logone 

 rivers; Lake Chad; the lower Nile from Cairo to the Delta Lakes; the 

 Jordan River system; the Na'aman and Yarkon rivers of Israel; lakes 

 Huleh and Kinnereth; Ein Feshkha; and the Dead Sea (Trewavas 1983). 



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Brimleyana 17:27-35, December 1991 27 



