The literature on this species has references to three subspecies: T. ren. rendalli, T. ren. swierstrae, and T. ren. gefuensis (see Thys van den Audenaerde 1968). These subspecific names are not universally agreed and are not commonly found in the literature on aquaculture of this species. T. rendalli is one of a group of several substrate-spawning tilapias that were formerly called ‘Tilapia melanopleura’ by some authors. T. melanopleura is no longer a valid name. Trewavas (1982) has described the problems caused by previous inaccurate nomenclature of this and related species and listed the characteristics that distinguish T. rendalli from other species which it was sometimes confused.

Common Names: Red Breasted Tilapia, Mudile (Tonga), Rooiborskurper (Afrikaans), Chilunguni (Chichewa).

History of Use: A popular foodfish throughout subSaharan Africa. Probably first cultured experimentally in Zaïre in the late 1930’s and established in smallholder ponds in that country by 1947. Although now largely abandoned in Zaïre in favor of other species, still widely cultured by African smallholders for subsistence in low-input systems.

Production Statistics: 843 tons reported to FAO in 1995 from Malawi, Zambia, Colombia, and Dominican Republic. Other countries that farm this tilapia combine population statistics with those for tilapiine cichlids.

Where Farmed: West, Central and, particularly, Southern Africa. According to Coche et al (1994), T. rendalli is the fourth most widely cultured species reported in a recent sample of subSaharan African countries. Countries reporting farmed T. rendalli production are: Colombia, the Dominican Republic, Malagasy Republic, Malawi, Nigeria, Tanzania, Zambia, Zimbabwe.

Climate and Environmental Tolerance: tropics, can withstand temperatures of 10-40° C. Spawns at temperatures above 20 and of up to at least 30° C. For juveniles, which often forage in very shallow littoral areas, Caulton (1976) demonstrated a temperature preferendum of 35-37° Reported to survive salinities of 13, 18 and 26 ppt.

Current Farming Methods: Commercially produced in a cage-based system in Mazvikadei Dam, Zimbabwe; otherwise in small ponds generally of no more than 550 m2. Can support commercial fisheries when stocked into managed reservoirs. Pond inputs are green, leafy materials which are readily eaten by T. rendalli of over 20 g. Smaller individuals are largely omnivorous. T. rendalli is a voracious feeder and can consume up to 20% of its body weight per day in fresh green materials. A range of plants suitable for feeding T. rendalli ponds was documented by Chikafumbwa et al. (1991). Chikafumbwa (1996) found that an input rate of 50 kg dry matter.ha-1.day-1 resulted in optimal performance. Typical specific growth rates at this input rate are between 0.45 and 0.50 % per day. Survival in ponds is normally around 70% as T. rendalli is less hardy and more easily captured by predators than other tilapiine cichlids.

Fry production by T. rendalli is considerably less than for the commonly cultured Oreochromis species. Costa-Pierce (1996) reported that, although these fish are substrate spawners, there was no difference between fry production in tanks with or without sand substrates. Fry production from the 1 male : 2 females (average weight 40 g) in that study was between 750 and 900 fry per female over 416 days. Brummett (1997) obtained between 3,000 and 5,000 fry of at least 2 g individual weight over a 9 month period in ponds which were seined with a reed fence either every 60 or 30 days, respectively. Brummett and Noble (1995) reported maximum fry production from 200 m2 ponds stocked with 100 male : 100 female broodstock (average weight 50 g) of over 400 fry per female per two week harvesting interval.

Processing and Marketing: In Southern Africa, normally sold whole and fresh on smallholder pond banks. Splitting and smoking is the preferred method for preservation. Marketed in subSaharan Africa at any size over 50 g.

Likely Future Trends: Will remain an important species for farming by smallholders, but could become a more widely farmed commercial species in systems based on feeding with plant proteins rather than fishmeal. Trials at a commercial farm near Banket, Zimbabwe showed that all-male T. rendalli populations in cages fed with pelleted feeds grew as well as Oreochromis niloticus under similar conditions.

References:

Brummett, R.E. 1997. Production of Tilapia rendalli fingerlings under Malawian smallholder conditions, p 273-286. In K. Fitzsimmons (ed.) Tilapia Aquaculture: Proceedings from the Fourth International Symposium on Tilapia in Aquaculture. NRAES-106. Northeast Regional Agricultural Engineering Service, Cornell University, New York, USA.

Brummett, R.E. and R.P. Noble. 1995. Aquaculture for African smallholders. ICLARM Technical Report 46. International Center for Living Aquatic Resources Management, Manila, Philippines.

Caulton, M.S. 1976. The energetics of metabolism, feeding and growth of sub-adult Tilapia rendalli. PhD Dissertation, University of Zimbabwe, Harare.

Chikafumbwa, F.J.K. 1996. Use of terrestrial plants in aquaculture in Malawi, p 175-182. In R.S.V. Pullin, J. Lazard, M. Legendre, J.B. Amon Kothias and D. Pauly (eds.) The Third International Symposium on Tilapia in Aquaculture. ICLARM Conference Proceedings 41, International Center for Living Aquatic Resources Management, Manila, Philippines.

Chikafumbwa, F.J.K., B.A. Costa-Pierce and J.D. Balarin. 1991. Preference of different terrestrial plants as food for Tilapia rendalli and Oreochromis shiranus. Aquabyte, the Newsletter of the Network of Tropical Aquaculture Scientists 4(3):9-10.

Coche, A.G., B.A. Haight and M.M.J. Vincke. 1994. Aquaculture development and research in sub-Saharan Africa. CIFA Technical Paper 23. Food and Agriculture Organization of the United Nations, Rome, Italy.

Costa-Pierce, B.A. 1996. Effects of substrate and water quality on seasonal fry production by Tilapia rendalli in tanks, p 280-289. In R.S.V. Pullin, J. Lazard, M. Legendre, J.B. Amon Kothias aned D. Pauly (eds) The Third International Symposium on Tilapia in Aquaculture. ICLARM Conference Proceedings 41, International Center for Living Aquatic Resources Management, Manila, Philippines.

Thys van den Audenaerde, D.F.E. 1968. An annotated bibliography by Tilapia (Pisces, Chichlidae). Documentation Zoologique No. 14. Museé Royale de l’Afrique Centrale, Tervuren, Belgium.

Trewavas, E. 1982. Tilapias: taxonomy and speciation, p. 3-13. In R.S.V. Pullin and R.H. Lowe-McConnell (eds.) The biology and culture of tilapias. ICLARM Conf. Proc. 7. ICLARM, Manila, Philippines.

Randall E. Brummett