Growth, Mortality and Yield-per-recruit of Nile Tilapia (<em>Oreochromis niloticusM/em>) in Garmat Ali River, Iraq


  • Ayat N. Salman Basrah University, Iraq
  • Abdul-Razak M Mohamed Basrah University, Iraq



Nile tilapia, growth and mortality, yield-per-recruit, Garmat Ali River, Iraq


The study was conducted to estimate the growth, mortality, recruitment and yield-per-recruit of Oreochromis niloticus from Garmat Ali River, Basrah, Iraq from October 2019 to September 2020. The population parameters were analyzed using the FAO-ICLARM stock assessment tool (FiSAT). A total of 2696 O. niloticus ranged from 7.0 to 25.0 cm and the sizes 13.0-18.0 cm constituted 64.2% of the total catch. The length-weight relationship was W= 0.012L3.109 suggesting that the species shows positive allometric growth. The growth parameters for the species were estimated as L∞= 30.45 cm, K= 0.45, to= -0.313 and Ǿ= 2.622. The coefficients of total mortality (Z), natural mortality (M) and fishing mortality (F) were 3.26, 1.03 and 2.24, respectively. The exploitation rate for the species computed to be 0.69. Fish were recruited to the fishery at a mean size of L50= 14.92 cm. The peak of recruitment was 23.51% in June. The analysis of yield-per-recruit (Y/R’) indicates that stock is not being overfished since the present exploitation rate was below the biological target reference points (E0.1 and Emax). So, more yields could be achieved by reducing the mesh sizes of the nets for fishing the species

Author Biography

Abdul-Razak M Mohamed, Basrah University, Iraq

Department of Fisheries

College of Agriculture


Boyd EC. “Farm-level issues in aquaculture certification: tilapia”. Report commissioned by WWF-US in 2004. Auburn University, Alabama, 2004.

Lévêque C. ‘Out of Africa: The success story of tilapias’. Environmental Biology of Fishes, vol 64, pp. 461-464, 2002.

Zengeya TA, Robertson MP, Booth AJ, Chimimba CT. “Ecological niche modeling of the invasive potential of Nile tilapia Oreochromis niloticus in African river systems: concerns and implications for the conservation of indigenous congenerics”. Biological Invasions, vol 15, pp. 1507-1521, 2013.

FAO. “Cultured Aquatic Species Information Programme Oreochromis niloticus (Linnaeus, 1758)”. Oreochromis_niloticus /en. October 2020 version.

Snoeks J, Freyhof J, Geelhand D, Hughes A. “Oreochromis niloticus. The IUCN Red List of Threatened Species 2018”. e.T166975A49922878. UK.2018.1.RLTS.T166975 A49922878.en.

FAO. “GLOBEFISH Highlights-A quarterly update on world seafood Markets”. January 2019 Issue. Food and Agriculture Organization of the United Nations, Rome, Italy, 2019.

Ahmed KKU, Amin SMN, Haldar GC, Dewan S. “Population dynamics and stock assessment of Oreochromis niloticus (Linnaeus) in the Kaptai Reservoir, Bangladesh”. Indian J. Fish., vol 50(1), pp. 47-52, 2003.

Njiru M, Getabu A, Jembe T, Ngugi C, Owili M, van Knaap M. “Management of the Nile tilapia (Oreochromis niloticus (L.)) fishery in the Kenyan portion of Lake Victoria, in light of changes in its life history and ecology”. Lakes and Reservoirs: Research and Management, vol 13, pp. 117-124, 2008.

Novaes JLC, Carvalho ED. “Reproduction, food dynamics and exploitation level of Oreochromis niloticus (Perciformes: Cichlidae) from artisanal fisheries in Barra Bonita Reservoir, Brazil”. Revista de biologia tropical, vol 60(2), pp. 721-734, 2012.

El-Bokhty EEB, El-Far AM. “Evaluation of Oreochromis niloticus and Tilapia zillii fisheries at Aswan region, River Nile, Egypt”. Egyptian Journal of Aquatic Biology and Fisheries, vol 18(3), pp. 79-89, 2014.

El-Kasheif MA, Authman MMN, Al-Ghamdi FA, Ibrahim SA, El-Far AM. “Biological Aspects and Fisheries Management of Tilapia Fish Oreochromis niloticus (Linnaeus, 1758) in El-Bahr El-Faraouny Canal, Al- Minufiya Province, Egypt”. Journal of Fisheries and Aquatic Science, vol 10(6), pp. 405-444, 2015.

Yongo E, Outa N. “Growth and population parameters of Nile tilapia, Oreochromis niloticus (L.) in the open waters of Lake Victoria, Kenya”. Lakes and Reservoirs: Research and Management, vol 21, pp. 375–379, 2016.

Alemu Y, Snoeks J, Teklegiorgis Y, Nyssen J, Brendonck L. “Assessing sustainable fishing yields using length-based analytical models: A case study with Nile tilapia in Lake Hawassa (Ethiopia)”. Journal of Fisheries and Livestock Production, vol 5(4), pp. 1-10, 2017.

Ana Mehak YM, Mohsin M, Noman M, Nazir K. “Population dynamics of Nile Tilapia (Oreochromis niloticus) at Chashma Barrage, Pakistan”. Indian Journal of Geo Marine Sciences, vol 46(01), pp. 206-210, 2017.

Shija BS, Tesfaye G, Dadebo E. “Assessment of Maximum Sustainable Yield and Optimum Fishing Effort for the Nile Tilapia (Oreochromis niloticus L.) in Lake Chamo, Ethiopia”. Journal of Agriculture and Environmental Sciences, vol 4(2), pp. 69-86, 2019.

Al-Faisal AJ, Mutlak F.M. “First record of the Nile tilapia Oreochromis niloticus (Linnaeus, 1758), from the Shatt Al-Arab River, Southern Iraq”. Mesopotamia Journal of Marine Sciences, vol 29(1), pp. 45-50, 2014.

Abulheni AKJ, Abbas LM. “First record of the Tilapia Oreochromis niloticus (Linnaeus,1758) in Euphrates River at Al-Hindia Barrier, Middle of Iraq”. Journal of the University of Kerbala. Speciel issue, pp. 18-21, 2017.

Khalifa SZ. “Ecological and biological of Nile tilapia Oreochromis niloticus and blue tilapia Oreochromis aureus from Tigris River, Southern Baghdad”. MSc. Thesis. University of Diyala, Iraq. 123p, 2017.

Mohamed ARM, Abood AN. “Compositional change in fish assemblage structure in Shatt Al-Arab River, Iraq”. Asian Journal of Applied Sciences, vol 5(5), pp. 944-958, 2017.

Mohamed ARM, Hussein SA, Lazem LF. Spatiotemporal variability of fish assemblage in the Shatt Al-Arab River, Iraq. Basrah Journal of Agricultural Sciences, vol 26(1), pp. 43-59, 2013.

Mohamed ARM, Hameed EK. “Impacts of saltwater intrusion on the fish assemblage in the middle part of Shatt Al-Arab River, Iraq”. Asian Journal of Applied Sciences, vol 7(5), pp. 577-586, 2019.

Negaud KZ. “Some biological aspects of Nile tilapia Oreochromis niloticus L. in AL-Rumaitha district, Al-Muthanna province, southern Iraq”. MSc. Thesis, University of Al-Muthanna, Iraq. 83p, 2019.

AL-Shamary ACh. “Effect of alien species on assemblage fish in Shatt Al-Arab river and East Al-Hammar Marsh”. Mesopotamia Environmental Journal, Special Issue A, pp. 18-32, 2016.

Abdullah SA. “Diversity of fishes in the lower reaches of Tigris River, north east of Basrah province, Southern Iraq”. Basrah Journal of Agricultural Sciences, vol 30(1), pp. 85-96, 2017.

Abdullah AHJ, Abdullah SA, Al-Robayii OA. “Spatial and temporal pattern of sympatric fish assemblage in the Al-Sweib River South of Iraq”. Proceedings of the 3rd Agricultural Scientific Conference 5-6 March 2018. The University of Kerbala, pp. 1-17, 2018.

Abdullah SA, Abdullah AHJ, Ouda YW. “Diversity and status of fish fauna in the Al-Kahlaa River, in Missan Province-Iraq, with notes on environmental variables”. EurAsian Journal of BioSciences, vol 13, pp. 1817-1824, 2019.

Canonico GC, Artihington A, McCrary JK, Thieme ML. “The effects of introduced tilapias on native biodiversity”. Aquatic Conservation: Marine and Freshwater Ecosystems, vol 15, pp. 463-483, 2005.

Simoes Vitule JR, Freire CA, Simberloff D. “Introduction of non-native freshwater fish can certainly be bad. Fish and Fisheries, vol 10, pp. 98-108, 2009.

Genner MJ, Connell E, Shechonge A, Smith A, Swanstrom J, Mzighani S, Mwijage A, Ngatunga BP, Turner GF. “Nile tilapia invades the Lake Malawi catchment”. African Journal of Aquatic Science, vol 38, pp. 85-90, 2013.

Vicente IST, Fonseca-Alves CE. “Impact of introduced Nile tilapia (Oreochromis niloticus) on non-native aquatic ecosystem”. Pakistan Journal of Bioogical Sciences, vol 16(3), pp. 121-126, 2013.

Mohamed ARM, Abood AN. “Population dynamics and management of two cichlid species in the Shatt Al-Arab River, Iraq”. Journal of Applied and Natural Science, vol 12(2), pp. 261-269, 2020.

Gayanilo FCJr, Sparre P, Pauly D. “FAO-ICLARM Stock Assessment Tools II (FiSAT II)”. Revised version. User's guide. FAO Comp. Info. Ser. (Fisheries), vol 8, pp. 1-168, 2005.

Le Cren ED. “The length-weight relationship and seasonal cycle in gonad weight and condition in the perch (Perca fluviatilis)”. Journal Animal of Ecology, vol 20, pp. 201-219, 1951.

Ricker WE. “Computation and interpretation of biological statistics of fish populations”. Bull. Fish. Res. Bd. Canada, vol 191, pp. 1-382, 1975.

Pauly D. “Some simple methods for assessment of tropical fish stocks. FAO Fish. Tech. Pap., 234: 52p, 1983.

Sparre P, Venema SC. “Introduction to tropical fish stock assessment”. Part 1. Manual. FAO fisheries technical paper. No. 306. 1, Rev. 2. FAO, Rome, Italy. 407 p, 1998.

Pauly D, Munro JL. “Once more on the comparison of growth in fish and invertebrates”. ICLARM Fishbyte, vol 2(1), pp. 21, 1984.

Pauly D. “On the interrelationships between natural mortality, growth parameters and mean environmental temperature in 175 fish stocks”. J. Cons. CIEM, vol 39(3), pp. 175-192, 1980.

Gulland JA. “Fish resources of the Ocean”. Fishing News Books, Surrey, London, England. 255p, 1971.

Pauly D.“A review of the ELEFAN system for analysis of length-frequency data in fish and aquatic invertebrates”. In: Pauly D, Morgan GR. (eds.). Length-based Methods in Fisheries Research, 13. ICLARM, 1987.

Beverton RJH, Holt SJ. “Manual of methods for fish stock assessment”. Part II. Fish. Biol. Tech. Pap., vol 38, pp. 10-67, 1966.

Pauly D, Soriano ML. “Some practical extensions to Beverton and Holt's relative yield-per-recruit model”. In: Maclean JL, Dizon LB, Hosillo LV. (eds.). The First Asian Fisheries Forum, pp. 491-496, 1986.

Cadima EL. “Fish stock assessment manual”. FAO Fisheries Technical Paper. No. 393. Rome, FAO. 161p, 2003.

Kebtieneh N, Alemu Y, Tesfa M. “Stock Assessment and Estimation of Maximum Sustainable Yield for Tilapia Stock (Oreochromis niloticus) in Lake Hawassa, Ethiopia”. Agriculture, Forestry and Fisheries, vol 5(4), pp. 97-107, 2016.

El-Bokhty EEB. “Assessment of family Cichlidae inhabiting Lake Manzala, Egypt”. Egyptian Journal of Aquatic Biology and Fisheries, vol 10, pp. 85-106, 2006.

Bwanika GN, Murie DJ, Chapman LJ. “Comparative age and growth of Nile tilapia (Oreochromis niloticus L.) in lakes Nabugabo and Wamala, Uganda”. Hydrobiologia, vol 589, pp. 287-301, 2007.

Mahmoud MH, Mazrouh MM. “Biology and fisheries management of tilapia species in Rosetta branch of the Nile River, Egypt”. Egyptian Journal of Aquatic Research, vol 34(3), pp. 272–285, 2008.

Shalloof KA, El-Far AM. “Age, growth and fishery biology of cichlid spp. In Abu-Zaabal Lakes, Egypt”. Egyptian Journal Aquatic Biology and Fisheries, vol 13, pp. 101-116, 2009.

Hirpo LA. “Reproductive biology of Oreochromis niloticus in Lake Beseka, Ethiopia”. Journal of Cell and Animal Biology, vol 7(9), pp. 116-120, 2013.

Hassan AA, El-Kasheif MA. “Age, growth and mortality of the cichlid fish Oreochromis niloticus (L.) from the River Nile at Beni Suef Governorate, Egypt”. Egyptian Journal Aquatic Biology and Fisheries, vol 17(4), pp. 1-12, 2013.

Mortuza MG, Al-Misned FA. “Length-weight Relationships, condition factor and sex-ratio of Nile Tilapia, Oreochromis niloticus in Wadi Hanifah, Riyadh, Saudi Arabia”. World Journal of Zoology, vol 8(1), pp. 106-109, 2013.

Kembenya EM, Ogellob EO, Githukiac CM, Aerad CN, Omondie R, Mungutif JM. “Seasonal changes of length-weight relationship and condition factor of five fish species in Lake Baringo, Kenya”. International Journal of Sciences: Basic and Applied Research, vol 14(2), pp. 130-140, 2014.

Shalloof KA, El-Far AM. “Length-weight relationship and condition factor of some fishes from the River Nile in Egypt with special reference to four tilapia species”. Egyptian Journal of Aquatic Biology and Fisheries, vol 21(2), pp. 33-46, 2017.

Teame T, Zebib H, Meresa, T. “Observations on the biology of Nile tilapia, Oreochromis niloticus L., in Tekeze Reservoir, Northern Ethiopia”. International Journal of Fisheries and Aquaculture, vol 10(7), pp. 86-94, 2018.

Enawgaw Y, Lemma B. “Seasonality in the diet composition and ontogenetic dietary shifts of (Oreochromis niloticus L.) (Pisces: Cichlidae) in Lake Tinishu Abaya, Ethiopia”. International Journal of Fisheries and Aquatic Research, vol 3(1), pp. 49-59, 2018.

Cuadrado JT, Lim DS, Alcontin RMS, Calang JL, Jumawan JC. “Species composition and length-weight relationship of twelve fish species in the two lakes of Esperanza, Agusan del Sur, Philippines”. FishTaxa, vol 4(1), pp. 1-8, 2019.

Mohamed ARM, Al-Wan SA. “Biological aspects of an invasive species of Oreochromis niloticus in the Garmat Ali River, Basrah, Iraq”. Journal of Agriculture and Veterinary Science, vol 13(2), pp. 15-26, 2020.

Nikolsky GV. “The ecology of fishes”. Academic Press, London and New York, 352 p, 1963.

Bwanika GN, Makanga B, Kizito Y, Chapman LJ, Balirwa J. “Observations on the biology of Nile tilapia, Oreochromis niloticus L., in two Ugandan crater lakes”. African Journal of Ecology, vol 42, pp. 93–101, 2004.

Riedel R, Caskey LM, Hurlbert SH. “Length-weight relations and growth rates of dominant fishes of the Salton Sea: implications for predation by fish-eating birds”. Lake and Reservoir Management, vol 23, pp. 528-535, 2007.

King MM. “Fisheries Biology, Assessment and Management”. 2nd ed. Blackwell Publishing Ltd, 400p, 2007.

Froese R, Tsikliras AC, Stergiou KI. “Editorial note on weight length relations of fishes”. Acta Ichthyol Piscat, vol 41, pp. 261–263, 2011.

Froese R. (2006). “Cube law, condition factor and weight–length relationships: history, meta-analysis and recommendations”. Journal of Applied Ichthyology, vol 22(4), pp. 241-253.

Santos AFG, Santos LN, Araujo FG. “Water level influences on body condition of Geophagus brasiliensis (Perciformes: Cichlidae) in a Brazilian oligotrophic reservoir”. Neotropical Ichthyology, vol 2(3), pp. 151-156, 2004.

Wootton RJ. “Growth: environmental effects”. In: Farrell AP. (ed.). Encyclopedia of fish physiology: from genome to environment. Elsevier Science Publishing Co. Inc, USA, pp. 1629-1635, 2011.

Panda D, Mohanty SK, Pattnaik AK, Das S, Karna SK. “Growth, mortality and stock status of mullets (Mugilidae) in Chilika Lake, India”. Lakes and Reservoirs, vol 2018, pp. 1-13, 2018.




How to Cite

Salman , A. N. ., & Mohamed, A.-R. M. (2020). Growth, Mortality and Yield-per-recruit of Nile Tilapia (<em>Oreochromis niloticusM/em>) in Garmat Ali River, Iraq. Asian Journal of Applied Sciences, 8(6).