Brief Summary
provided by EOL authors
Native to Africa and the Middle East,
Oreochromis aureus, commonly known as blue tilapia, is a cichlid fish that has been widely introduced around the world to countries including the United States, Central and South America, southeast Asia, Polynesia and Africa as a low cost, high protein food source. Blue tilapia are hardy, tolerant of a wide range of temperatures (8-30 degrees C), salinities and water qualities, and easy to rear in aquaculture (for this they are sometimes referred to as the “aquatic chicken”). However, this species is also aggressive and dominates other species in non-native environments; in many places, populations that have escaped and become established are difficult to manage and have caused displacement and decline of endemic species as well as significant disruption of fish ecosystems. The Invasive Species Specialist Group (ISSG) has declared
O. aureus one of the world’s 100 worst invasive species. (
Global Invasive Species Database, Invasive Species Specialist Group (ISSG) a;
Global Invasive Species Database, Invasive Species Specialist Group (ISSG) b;
Wikipedia 2012)
Diagnostic Description
provided by Fishbase
Diagnosis: Adults: narrow preorbital bone (depth max. 21.5% of head length in fishes up to 21.3cm SL); lower pharyngeal jaw with short blade; no enlargement of the jaws in mature fish (lower jaw not exceeding and usually less than 36.8% head length) (Ref. 2). Caudal without regular dark vertical stripes (Ref. 2, 53405, 54467), but with a broad pink to bright red distal margin (Ref. 2). Breeding males assume an intense bright metallic blue on the head, a vermilion edge to the dorsal fin and a more intense pink on the caudal margin (Ref. 2, 54467). Breeding females with the edges of dorsal and caudal fins in a paler more orange color (Ref. 2). Juveniles: upper line of head profile running upward from snout at sharp angle; lower pharyngeal bone nearly triangular, teeth numerous but not densely crowded; dorsal and anal fin striped, with stripes running obliquely on the soft dorsal and longitudinally on the caudal fin; black Tilapia-mark on soft dorsal present; body dark; lower lip developed from beneath (Ref. 54566).Description: deep bodied; teeth very small, typical for an algae feeder (Ref. 52307), in 3-5 rows in the jaws, bicuspid in the outermost (Ref. 2, 53405, 54467), tricuspid in the others (Ref. 2, 54467). Lower pharyngeal bone with bicuspid teeth, its toothed part as long as anterior part (Ref. 53405). Scales cycloid (Ref. 367, 2756, 54408), with fringes of the embedded part almost straight (Ref. 54408). Scales on cheek in 2-3 horizontal series; 5-7 scales between base of pectoral and pelvic fin (Ref. 2, 54467). 13.5-14.5 scales below upper lateral line before the pelvic fins (Ref. 367). 2 scales between upper and lower lateral line (Ref. 367, 2756). Upper lateral line with 20-23 scales, lower with 14-18 scales (Ref. 367, 2756). Microbranchiospines present on outer sides of arches 2 to 4 (Ref. 2). Dorsal fin edge thickened and notches between lappets closed in fully ripe males (Ref. 364, 54467). Last dorsal spine the longest (Ref. 367, 2756). Third anal spine a little shorter than last dorsal spine (Ref. 2, 2756, 54467), but stronger (Ref. 2, 54467). Pelvics not greatly produced; caudal often with rounded corners, usually scaly only at the base and between rays on upper and lower parts of the fin; genital papilla of mature male conical or with narrow bifid flange (Ref. 2, 54467).Coloration: Juveniles: grey-brown to slightly golden (Ref. 52307), with vertical bars on sides (Ref. 53405). Specimens
- Recorder
- Crispina B. Binohlan
Trophic Strategy
provided by Fishbase
Cold tolerant (Ref. 61), occuring at temperatures ranging from 8°-30°C, with small size fish less tolerant to low temperatures than larger specimens (Ref. 2). Tolerates fairly brackish conditions (Ref. 3, 61, 2001, 6465, 54362), with small specimens less tolerant than larger ones (Ref. 96, 54403, 54459) and ontogenetic changes in salinity tolerance related to body size rather than to chronological age (Ref. 54403, 54459). Forms schools; is sometimes territorial; inhabits warm ponds and impoundments as well as lakes and streams (Ref. 5723, 11028), in open water as well as among stones and vegetation (Ref. 11028). Omnivorous (Ref. 61, 52307), but with a tendency towards a vegetarian diet (Ref. 52307). Feeds on phytoplankton and small quantities of zooplankton (Ref. 3, 61, 6465, 52307). Young fish have a more varied diet which includes large quantities of copepods and cladocerans (Ref. 2, 61, 6465), but they also take pieces of small invertebrates (Ref. 52307). Particulate feeder during larval and juvenile stages, filter feeder when adult (Ref. 46977). Ovophilic, agamous (Ref. 52307), maternal mouthbrooder (Ref. 364, 52307). Reproduces in both fresh and brackish water (Ref. 61, 5723).
- Recorder
- Crispina B. Binohlan
Morphology
provided by Fishbase
Dorsal spines (total): 14 - 17; Dorsal soft rays (total): 11 - 15; Analspines: 3; Analsoft rays: 8 - 11; Vertebrae: 28 - 31
- Recorder
- Crispina B. Binohlan
Migration
provided by Fishbase
Potamodromous. Migrating within streams, migratory in rivers, e.g. Saliminus, Moxostoma, Labeo. Migrations should be cyclical and predictable and cover more than 100 km.
Life Cycle
provided by Fishbase
Nesting usually in shallow water weedy areas (Ref. 96). Males establish territory and dig a spawning pit (Ref. 2, 6465, 54601), using mouth and fins (Ref. 2), up to 60cm deep and 4-6m in diameter; a number of territories can often be found clustered together (Ref. 52307). Territories are defended by means of agressive behaviour (Ref. 6465), including lateral display, lateral biting and mouth-to-mouth combat (Ref. 2). Reproduction is stimulated by long photoperiods and inhibited by short daylengths (Ref. 54365). Reproduction requires a minimum temperature of about 20°C (Ref. 2). Males visit schools of females and attempt to attract a female spawning partner (Ref. 2, 52307). Courting behaviour in the nest consists of lateral display by both sexes with nipping and tail-flapping (Ref. 2). Eggs are deposited in single clutches, from several dozen to 100 eggs (Ref. 52307), and are taken into the females mouth as soon as they are fertilized (Ref. 2, 6465, 52307), with a peak spawning frequency around the 9-11th hour of light (Ref. 31140, 54365). One female may hold up to 2000 eggs in her mouth (Ref. 2). The female swims away to deeper water with the brood after spawning is complete (Ref. 2, 52307), while the male renews spawning activities with another female. Hatching occurs about 3 days after oviposition (Ref. 2). Incubation time varies with temperature, 13-14 days at 25-27°C (Ref. 2, 52307) or 8-10 days at 29°C (Ref. 144), and juveniles leave the mother's mouth when they are about 1.1cm in length (Ref. 54601). The young school near parent's head for a few days, reentering the mouth at any sign of danger or at a gesture of the female; parent-offspring relationship ceases after 5 days (Ref. 2).
- Recorder
- Crispina B. Binohlan
Diseases and Parasites
provided by Fishbase
Centrocestus Disease. Parasitic infestations (protozoa, worms, etc.)
Diseases and Parasites
provided by Fishbase
Sanguinicola Disease. Parasitic infestations (protozoa, worms, etc.)
Diseases and Parasites
provided by Fishbase
Whirling Viral Disease of Tilapia Larvae. Viral diseases
Diseases and Parasites
provided by Fishbase
Ichthyobodo Infection 2. Parasitic infestations (protozoa, worms, etc.)
Diseases and Parasites
provided by Fishbase
Gnathostoma Disease (larvae). Parasitic infestations (protozoa, worms, etc.)
Diseases and Parasites
provided by Fishbase
Goezia Disease 2. Parasitic infestations (protozoa, worms, etc.)
Diseases and Parasites
provided by Fishbase
Saccocoelioides Infection. Parasitic infestations (protozoa, worms, etc.)
Biology
provided by Fishbase
Cold tolerant (Ref. 23, 61, 55352), occuring at temperatures ranging from 8°-30°C (Ref. 2), tolerating up to 41 °C (Ref. 23). Tolerates fairly brackish conditions (Ref. 3, 23, 61, 2001, 6465, 54362). Forms schools; is sometimes territorial; inhabits warm ponds and impoundments as well as lakes and streams (Ref. 5723, 11028), in open water as well as among stones and vegetation (Ref. 11028). Feeds on phytoplankton and small quantities of zooplankton (Ref. 3, 61, 6465, 52307). Young fish have a more varied diet which includes large quantities of copepods and cladocerans (Ref. 2, 61, 6465), but they also take pieces of small invertebrates (Ref. 52307). Ovophilic, agamous (Ref. 52307), maternal mouthbrooder (Ref. 364, 52307). Sexual maturity in ponds reached at age of 5-6 months (Ref. 55352). Reproduces in both fresh and brackish water (Ref. 61, 5723). Good taste (Ref. 61).
Importance
provided by Fishbase
fisheries: highly commercial; aquaculture: commercial; aquarium: commercial; bait: usually
Oreochromis aureus
provided by wikipedia EN
The blue tilapia (Oreochromis aureus) is a species of tilapia, a fish in the family Cichlidae.[2] Native to Northern and Western Africa, and the Middle East, through introductions it is now also established elsewhere, including parts of the United States, where it has been declared an invasive species and has caused significant environmental damage.[3] It is known as the blue kurper in South Africa.[4]
Description
In their introduced US range, blue tilapia are usually 120 to 200 millimetres (4+3⁄4 to 7+3⁄4 in) in length,[3] and reach weights up to 5 to 6 lb (2.3 to 2.7 kg).[5] The largest recorded specimen was more than 21 in (53 cm) long and weighed more than 10 lb (4.5 kg).[5] Blue tilapia are mouthbrooders, and broods range from 160 to 1600 eggs per female.[3] O. aureus is primarily herbivorous, but occasionally consumes zooplankton;[3] the young include small invertebrates in their diet.[2]
Range and habitat
The blue tilapia is native to Northern and Western Africa, and the Middle East. In Africa, it is native to the Senegal, Niger, Benue and lower Nile Rivers. In the Middle East, it is native to the Jordan River.[2] Through introductions, the fish can be found in the United States in Texas, Alabama, Florida, and Nevada. It has also been established in Central and South America, and Southeast Asia.[2] The original stocks of O. aureus in the United States were from Israel.[6]
The blue tilapia is primarily a fresh and brackish water fish that occurs in a wide range of habitats such as streams, rivers, lakes and ponds,[1] but it has a high tolerance for salt water and even hypersaline conditions at up to 4.5% salinity (seawater is about 3.5%).[7] It primarily occurs in waters that range from 12 to 32 °C (54–90 °F),[7] but tolerates between 8 and 40 °C (46–104 °F).[2]
Israel
In Israel, Oreochromis aureus is also known as Jordan St. Peter's fish and was traditionally coming down the Jordan River from Lake Huleh to the Sea of Galilee.[8] It is black and larger than the white "Common St. Peter's fish" or simply "St. Peter's fish" (Coptodon zillii, مشط musht in Arabic and adopted into Modern Hebrew, lit. "comb").
Another "St. Peter's fish" is the "Galilee St. Peter's fish" (mango tilapia, Sarotherodon galileus; Arabic مشط أبيض musht 'abyad), which is white and also larger than C. zillii.[8]
Invasive species
Oreochromis aureus has been introduced in many places around the world for use as a food fish, and frequently in order to control aquatic vegetation.[9] Its presence may have in many cases been mis-documented as Oreochromis niloticus, because the two species were only recently distinguished.[9]
In the United States
Since its introduction into Florida in 1961,[5] the fish has increased its range and frequency of occurrence. It is now the most widespread foreign species in Florida, with established populations as far north as Lake Alice, in Gainesville.[6] It is a major management problem for the National Park Service due to its predominance in Taylor Slough in Everglades National Park, where it has changed the fish community structure.[6] The species is also expanding its range in Texas. It was at one time responsible for inhibition of the population of largemouth bass in Lake Trinidad (in Henderson County) until it was extirpated, and is implicated in the unionid mussel declines in two bodies of water in Texas.[6] It is also blamed for a severe decline in native fish populations in Warm Springs Natural Area, Nevada.[6]
References
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^ a b Awaïss, A.; Azeroual, A. & Lalèyè, P. (2010). "Oreochromis aureus". IUCN Red List of Threatened Species. 2010: e.T166933A6293372. Retrieved 4 February 2019.
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^ a b c d e "Oreochromis aureus". FishBase. Retrieved 2008-06-29.
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^ a b c d "Fact Sheet for Oreochromis aureus (Steindachner, 1864)". Gulf States Marine Fisheries Commission. Archived from the original on 2008-05-02. Retrieved 2008-06-28.
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^ "Blue Kurper". Flyloops. Archived from the original on 2018-09-06. Retrieved 2012-03-22.
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^ a b c "Florida's Exotic Freshwater Fishes". State of Florida, Division of Freshwater Fisheries. Archived from the original on 2008-07-03. Retrieved 2008-06-29.
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^ a b c d e "NAS Species Fact Sheet". US Geological Survey. Archived from the original on 2009-01-09. Retrieved 2008-06-30.
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^ a b Ford, A.G.P.; et al. (2019). "Molecular phylogeny of Oreochromis (Cichlidae: Oreochromini) reveals mito-nuclear discordance and multiple colonisation of adverse aquatic environments" (PDF). Mol. Phylogenet. Evol. 136: 215–226. doi:10.1016/j.ympev.2019.04.008. PMID 30974200. S2CID 109938635.
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^ a b Aharon Geva-Kleinberger, Autochthonous Texts in the Arabic Dialect of the Jews of Tiberias, Otto Harrassowitz, Wiesbanden 2009, volume 046, pp. 67 and 107, ISBN 978-3-447-05934-3 [1]
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^ a b "Global Invasive Species Database". Retrieved 31 July 2014.
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- Wikipedia authors and editors
Oreochromis aureus: Brief Summary
provided by wikipedia EN
The blue tilapia (Oreochromis aureus) is a species of tilapia, a fish in the family Cichlidae. Native to Northern and Western Africa, and the Middle East, through introductions it is now also established elsewhere, including parts of the United States, where it has been declared an invasive species and has caused significant environmental damage. It is known as the blue kurper in South Africa.
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- cc-by-sa-3.0
- copyright
- Wikipedia authors and editors
