Oreochromis aureus - Blue Tilapia

Information Last Reviewed Spring 2007

Taxonomy:

Phylum: Chordata

Class: Actinopterygii

Order: Perciformes

Family: Cichlidae

$image\oreochromis_aureus.jpg$

Identification:

Juvenile Morphology

Grey vertical bars present on body $image\30.jpg$
Caudal fin may have vertical bars $image\30.jpg$

Adult Morphology

Grey-blue coloration, darker above and white on belly $image\30.jpg$
May display dark vertical bars on body $image\30.jpg$

Dark and light spots alternating on posterior half of dorsal fin and upper margin vermilion or orange in coloration $image\30.jpg$
White spots on proximal half of caudal fin and posterior portion of anal fin $image\30.jpg$
Caudal fin with broad pink to red margin, anal fin light or with a few spots $image\30.jpg$
Eye with red iris and crossed by a black bar $image\30.jpg$
Broad pink to bright red distal margin on caudal fin $image\30.jpg$
Breeding males exhibit intense bright metallic blue coloration on head, vermilion edge to dorsal fin, increased brightness of coloration on caudal fin, and blue-black chin and chest $image\30.jpg$ $image\18.jpg$
Breeding females develop a lighter orange color on edges of dorsal and caudal fins $image\30.jpg$
Maximum length– 37 cm $image\18.jpg$

Distinguishing Characteristics

Blue tilapia is unlikely to be confused with native North American species but is similar to other introduced cichlids (Mossambique tilapia, Tilapia mossambica and Redbelly tilapia, T. zilli).

12–15 dorsal rays (as opposed to higher numbers in similar species) $image\18.jpg$
Lower gill rakers 18-26, compared to 6-12 in Tilapia $image\30.jpg$
Tilapia have little or no breeding coloration in males compared to Oreochromis $image\30.jpg$

General Biology:

Behavior

A schooling fish, excluding males in breeding condition $image\17.jpg$

Diet

Juveniles

Similar to adults but more varied. Insects (Tendipedidae and Ceratopogonidae) and small crustraceans were more important for smaller (< 13 cm) fish $image\17.jpg$

Adults

Long gut, 8.0-9.4 times standard length $image\1.jpg$
In Florida high intrapopulation diet variation was observed using stable isotope analysis- indicating food was consumed from both the water column and sediment $image\2.jpg$
May be able to shift feeding habits dependant on food sources available $image\13.jpg$
In Alabama adult (15-22 cm TL) diet consisted primarily of phytoplankton $image\17.jpg$
Other food items of lesser importance included Protozoa, Annelida, Formicidae, Rotifera, Nematoda, Oligochaeta, Trichoptera, Cladocera, Copepoda, Ostracoda, Diptera, inorganic remains, fry of blue tilapia, and unidentified eggs $image\17.jpg$ $image\26.jpg$

Life Cycle:

Growth

Found to live up to 5 years and obtain a total length of 315 mm $image\1.jpg$
Males grow faster than females $image\1.jpg$

Maturity

In native range sexual maturity occurs during second year $image\4.jpg$ $image\1.jpg$
Size at first spawn in native habitat is 18-20 cm TL $image\1.jpg$
In Alabama ovaries started to develop in some individuals only 50 days old and 10 cm in length $image\17.jpg$

Spawning

End of March to end of May in Israel $image\1.jpg$
Begins end of April in US $image\17.jpg$
Minimum spawning temperature 20-220 C, similar in both Israel25 and Alabama $image\17.jpg$
Male establishes breeding territory by excavating substrate and detritus to make nest (nest typically 60 cm deep) $image\17.jpg$
After nest construction male defends the nest against other males and establishes a territory approximately 2-3 meters in radius $image\30.jpg$ $image\17.jpg$
Males attract females from schools and lead them back to nest $image\17.jpg$
Eggs and milt are deposited in spawning pit (constructed by male) $image\17.jpg$
Females exhibit mouth brooding behavior and immediately remove the eggs/milt from the spawning pit and leave the male’s territory $image\30.jpg$
The male will then attempt to attract another female and will spawn with multiple females $image\17.jpg$
After releasing young, a female will prepare to spawn again, if the temperature is suitable $image\30.jpg$

Eggs

2.0 X 3.0 mm when mature $image\17.jpg$
There are typically several size classes of ova in ovaries at any given time $image\17.jpg$
In females 12.8–16.8 cm, egg numbers varied from 64 to 655 per spawn in Alabama $image\17.jpg$
A single female can hold up to 2000 eggs in her mouth $image\1.jpg$
Hatching occurs approximately three days following oviposition $image\30.jpg$

Juveniles

The female retains the young in her mouth subsequent to hatching for approx 13-14 days $image\17.jpg$
After leaving the mother, young remain in tight school near mother for several days and will reenter the mouth if threatened $image\17.jpg$

Habitat Characteristics:

Preferred Environment

Has been able to successfully colonize a wide variety of environments including high and low flow areas $image\13.jpg$
Inhabits shallow warmer water during day and moves to deeper water at night $image\17.jpg$
Appear to prefer soft mud/muck substrate $image\4.jpg$
Establish quickly in eutrophic lakes/reservoirs
Congregate in warm-water habitats from either artificial (power plants) or natural (thermal springs) sources during winter in United States $image\4.jpg$ $image\26.jpg$

Temperature

Adults could tolerate temperatures as low as 3 deg C for short time periods in Alabama $image\17.jpg$
Young were affected at temperatures as low as 9 deg C and adults at 7 deg C in Alabama $image\17.jpg$
Behavioral changes (reduced feeding) were seen between 13–16 deg C when acclimated to 28 deg C $image\25.jpg$
In Israel, fingerlings began to die at 9–11 deg C, depending on acclimatization temperature $image\7.jpg$
Death rate at 11 deg C was twice as high in freshwater as it was in 5-ppt seawater $image\7.jpg$

Oxygen

Able to withstand low dissolved oxygen by utilizing atmospheric oxygen $image\28.jpg$

Salinity

Growth rates were similar for blue tilapia held at freshwater, 6.5, 10 and 15.5% NaCl, although mortality was higher at higher salt concentrations $image\19.jpg$
Blue tilapia can spawn at 50% seawater, however survival of young is reduced $image\19.jpg$
Can survive transfer from freshwater to 60-70 percent seawater $image\5.jpg$

Water Quality

Can tolerate ammonia levels of 11 ppm at pH of 8 and 27 deg C $image\5.jpg$

Distribution:

Native Range

Israel, Lower Nile, West Africa $image\30.jpg$

North American Distribution

Established:

Arizona- Colorado River drainage $image\18.jpg$
Arkansas- lower Arkansas River $image\3.jpg$
California- Colorado River drainage $image\18.jpg$
Florida- multiple rivers, streams, lakes, and private ponds; considered the most widespread exotic in the state $image\11.jpg$ $image\14.jpg$
Nevada- Muddy River $image\18.jpg$
North Carolina- cooling impoundment $image\18.jpg$
Oklahoma- North Canadian River drainage $image\21.jpg$
Texas- several impoundments and Rio Grande, San Antonio and Guadalupe drainages $image\18.jpg$

Probable Means of Introduction

Pennsylvania- Escape from an aquaculture facility and subsequent establishment in warm water effluent $image\27.jpg$
For control of aquatic vegetation such as duckweed $image\22.jpg$ $image\31.jpg$
Purposeful release into waterways by private citizens $image\24.jpg$
Accidental escape from aquaculture facilities $image\16.jpg$

Impacts:

Negative

Ability to spread rapidly and in large numbers in suitable habitat $image\8.jpg$ $image\12.jpg$
In southwest United States and Florida, significant threat to native endemics in warmwater springs $image\23.jpg$ $image\32.jpg$
Competition with native shads for food may have resulted in shad population declines in lakes and reservoirs in Florida and Texas $image\15.jpg$ $image\29.jpg$ $image\33.jpg$
Competition with native cichlid species in Texas $image\12.jpg$
Potential competition for nest sites with native centrarchids $image\29.jpg$
Increased blue tilapia densities resulted in decreased largemouth bass populations in Texas, underlying cause unknown but attributed to either aggression or overcrowding $image\29.jpg$
Dispersal of exotic diseases and parasites $image\20.jpg$

Positive

Florida- introduction of blue tilapia has resulted in a substantial commercial fishery, providing jobs and increased revenue $image\14.jpg$

Management:

Control Measures

Cold shock in situations where tilapia have colonized warm waters from thermal effluents $image\27.jpg$

Literature:

Ben-Tuvia, A. 1959. The biology of the cichlid fishes of Lake Tiberias and Huleh. Bull. Res. Coun. Israel. B. Zool. 8B, No. 4 :153-188 (reprinted as Bull. Sea. Fish. Res. Sta. Israel No. 27, 1960).

Binhe, G., C.L. Schelske, and M.V. Hoyer. 1997. Intrapopulation feeding diversity in blue tilapia: Evidence from stable-isotope analyses. Ecology 78(7):2263-2266.

Buchanan, T.M., J. Smith, D. Saul, J. Farwick, T. Burnley, M. Oliver, and K. Shirley. New Arkansas records for two nonindigenous fish species, with a summary of previous introductions of nonnative fishes in Arkansas. Journal of the Arkansas Academy of Science 54(2000):143-145.

Buntz, J. and C.S. Manooch, III. 1968. Tilapia aurea (Steindachner), a rapidly spreading exotic in south central Florida. Proceedings of the Annual Conference Southeastern Association of Game and Fish Commissioners 22:495-501.

Chervinski, J. 1982. Environmental physiology of tilapias, p. 119-128. In R.S.V. Pullin and R.H. Lowe-McConnell (eds.) The biology and culture of tilapias ICLARM Conference Proceedings 7, 432 p. International Center for Living Aquatic Resources Management, Manila, Philippines.

Chervinski, J. and M. Zorn. 1974. Note on the growth of Tilapia aurea (Steindachner) and Tilapia zillii (Gervais) in sea-water ponds. Aquaculture 1:249-255.

Chervinski, J., and M. Lahav. 1976. The effect of exposure to low temperature on fingerlings of local tilapia (Tilapia aurea) (Steindachner) and imported tilapia (Tilapia vulcani) (Trewevas) and Tilapia nilotica (Linne) in Israel. Bamidgeh 28(1/2):25-29.

Courtenay, W.R., Jr., H.F. Sahlman, W.W. Miley, II, and D.J. Herrema. 1974. Exotic fishes in fresh and brackish waters of Florida. Biological Conservation 6(4):292-302.

Courtenay, W.R., Jr., D.A. Hensley, J.N. Taylor, and J.A. McCann. 1986. Distribution of exotic fishes in North America. Pages 675-698 in C.H. Hocutt, and E.O. Wiley, editors. The zoogeography of North American freshwater fishes. John Wiley and Sons, New York, NY.

Courtenay, W.R., Jr., and J.D. Williams. 1992. Dispersal of exotic species from aquaculture sources, with emphasis on freshwater fishes. p. 49-81 in A. Rosenfield, and R. Mann, (eds). Dispersal of living organisms into aquatic ecosystems. Maryland Sea Grant Publication, College Park, MD.

Crittenden, E. 1965. Status of Tilapia nilotica (Linneaus) in Florida. Proceedings of the Annual Conference Southeastern Association of Game and Fish Commissioners 16(1962):257-262.

Edwards, R.J. and S. Contreras-Balderas. 1991. Historical changes in the ichthyofauna of the lower Rio Grande (Rio Brova del Norte), Texas and Mexico. The Southwestern Naturalist 36(2):201-212.

Grabowski, S.J., S.D. Hiebert, and D.M. Lieberman. 1984. Potential for introduction of three species of nonnative fishes into central Arizona via the Central Arizona Project. A literature review and analysis. REC-ERC-84-7. U.S. Department of the Interior, Bureau of Reclamation, Denver, CO.

Hale, M.M., J.E. Crumpton and R.J. Schuler, Jr. 1995. From sportfishing bust to commercial fishing boon: A history of the blue tilapia in Florida. American Fisheries Society Symposium 15:425-430.

Hendricks, M.K. and R.L. Noble. 1980. Feeding interactions of three planktivorous fishes in Trinidad Lake, Texas. Proceedings of the Annual Conference Southeastern Association of Fish and Wildlife Agencies 33(1979):324-330.

Kushlan, J.A. 1986. Exotic fishes of the Everglades: a reconsideration of proven impact. Environmental Conservation 13:67-69.

McBay, L.G. 1961. The Biology of Tilapia nilotica Linnaeus. Proceedings of the Annual Conference Southeastern Association of Game and Fish Commissioners 15:208-218.

Page, L.M. and B.M. Burr. 1991. A field guide to freshwater fishes of North America north of Mexico. Houghton Mifflin Company, Boston. 432 p.

Payne, A.I. and R.I. Collinson. 1983. A comparison of the biological characteristics of Sarotherodon niloticus (L.) with those of S. aureus (Steindachner) and other tilapia of the delta and lower Nile. Aquaculture 30:335-351.

Philippart, J-Cl. And J-Cl. Ruwet. 1982. Ecology and distribution of tilipias, p. 15-59 in R.S.V. Pullin and R.H. Lowe-McConnell (eds.) The biology and culture of tilapias. ICLARM Conference Proceedings 7, 432 p. International Center for Living Aquatic Resources Management, Manila, Philippines.

Pigg, J. 1978. The tilapia Sarotherodon aurea (Steindachner) in the North Canadian River in central Oklahoma. Proceedings of the Oklahoma Academy of Science 58:111-112.

Robins, C.R., R.M. Bailey, C.E. Bond, J.R. Brooker, E.A. Lachner, R.N. Lea and W.B. Scott. 1991. World fishes important to North America. Exclusive of species from the continental waters of the United States and Canada. American Fisheries Society Special Publication 21:243 p.

Scoppettone, G.G., P.H. Rissler, M.B. Nielsen, and J.E. Harvey. 1998. The status of Moapa coriacea and Gila seminude and status information on other fishes of the Muddy River, Clark County, Nevada. The Southwestern Naturalist 43(2):115-122.

Shafland, P.L. 1979. Non-native fish introductions with special reference to Florida. Fisheries 4(3):18-23.

Shafland, P.L. and J.M. Pestrak. 1982. Lower lethal temperatures for fourteen non-native fishes in Florida. Environmental Biology of Fishes 7(2):149-156.

Spataru, P., and M. Zorn. 1978. Food and feeding habits of Tilapia aurea (Steindachner) (Cichlidae) in Lake Kinneret (Israel). Aquaculture 13:67-79.

Stauffer, J.R., S.E. Boltz, and J.M. Boltz. 1988. Cold shock susceptibility of blue tilapia from the Susquehanna River, Pennsylvania. North American Journal of Fisheries Management 8:329-332.

Stickney, R.R., L.O. Rowland and J.H. Hesby. 1977. Water quality- Tilapia aurea interactions in ponds receiving swine and poultry wastes. Proceedings of the World Mariculture Society 8:55-71.

Taylor, J.N., W.R. Courtenay, Jr., and J.A. McCann. 1984. Known impacts of exotic fishes in the continental United States, p. 322-373 in W.R. Courtenay, Jr., and J.R. Stauffer, Jr. Distribution, Biology and Management of Exotic Fishes. Johns Hopkins University Press. Baltimore.

Trewevas, E. 1983. Tilapiine Fishes of the Genera Sarotherodon, Oreochromis and Danakilia. British Museum of Natural History, Publ. Num. 878. Comstock Publishing Associates. Ithaca, New York. 583 pp.

Welcomme, R.L. 1988. International introductions of inland aquatic species. FAO Fish. Tech. Pap. No. 294. 318 p.

Zale, A.V. 1987. Periodicity of habitation of a stenothermal spring run in North-Central Florida by blue tilapia. North American Journal of Fisheries Management 7:575-579.

Zale, A.V., and R.W. Gregory. 1990. Food selection by early life stages of blue tilapia, Oreochromis aureus, in Lake George, Florida: overlap with sympatric shad larvae. Florida Scientist 53:123-129.

Additional Literature

Burgess, G.H., C.R. Gilbert, V. Guillory, and D.C. Taphorn. 1977. Distributional notes on some north Florida freshwater fishes. Florida Scientist 40(1):33-41.

Cnaani, A., G.A.E Gall, G. Hulata. 2000. Cold tolerance of tilapia species and hybrids. Aquaculture International 8(4):289-298.

Foote, K.J. 1977. Annual performance report: Blue tilapia investigations. Study I: Preliminary status investigations of blue tilapia. (Job I-1 through Job I-7; period July 6, 1976-June 30, 1977). Report to the Florida Game and Fresh Water Fish Commission. 71 pp.

Hogg, R.G. 1976. Established exotic cichlid fishes in Dade County, Florida. Florida Scientist 39(2): 97-103.

Hubbs, C., T. Lucier, G.P. Garett, R. J. Edwards, S. M. Dean, and E. Marsh. 1978. Survival and abundance of introduced fishes near San Antonio, Texas. The Texas Journal of Science 30(4):369-376.

Langford, F.H., F.J. Ware, and R.D. Gasaway. 1978. Status and harvest of introduced Tilapia aurea in Florida lakes. Pages 102-108 in R. O. Smitherman, W.L. Shelton, J.H. Grover, editors. Proceedings of the culture of exotic fishes symposium, fish culture section, American Fisheries Society, Auburn, AL.

Muoneke, M.I. 1988. Tilapia in Texas waters. Texas Parks and Wildlife Department, Inland Fisheries Data Series 9, Austin.

Noble, R.L., and R.D. Germany. 1986. Changes in fish populations of Trinidad Lake, Texas, in response to abundance of blue tilapia. Pages 455-461 in R. H. Stroud, editor. Fish culture in fisheries management. American Fisheries Society, Bethesda, MD.

Pelgren, D.W., and K.D. Carlander. 1971. Growth and reproduction of yearling Tilapia aurea in Iowa ponds. Proceedings of the Iowa Academy of Science 78:27-29.

Skinner, W.F. 1984. Oreochromis aureus (Steindachner; Cichlidae), an exotic fish species, accidentally introduced to the lower Susquehanna River, Pennsylvania. Proceedings of the Pennsylvania Academy of Science 58:99-100.

Smith-Vaniz, W.F. 1968. Freshwater Fishes of Alabama. Auburn University, Auburn, Alabama. 211 pp.

Swift, C.C., T.R. Haglund, M. Ruiz, and R.N. Fisher. 1993. The status and distribution of the freshwater fishes of southern California. Bulletin of the Southern California Academy of Science 92(3):101-167.

Zuckerman, L.D., and R.J. Behnke. 1986. Introduced fishes in the San Luis Valley, Colorado. Pages 435-452 in R. H. Stroud, editor. Fish culture in fisheries management. Proceedings of a symposium on the role of fish culture in fisheries management at Lake Ozark, MO, March 31-April 3, 1985. American Fisheries Society, Bethesda, MD.

Web Sites:

Gulf States Marine Fisheries Commission:

http://nis.gsmfc.org/nis_factsheet.php?toc_id=194

Fish Base:

http://www.fishbase.org/Summary/SpeciesSummary.cfm?genusname=Oreochromis&speciesname=aureus

USGS Nonindigenous Species Program:

http://nas.er.usgs.gov/queries/SpFactSheet.asp?speciesID=463