Investigating opportunities to support indigenous aquaculture in Australia : Visit to Kimberley, Western Australia, May 2003

The STREAM Initiative has been working with issues relating to livelihoods, policy and institutional development and communications throughout Asia-Pacific. Recently this has included work in India with indigenous communities supporting people to have a voice in policy making processes. There appear to be some parallels between this work and the objectives of Kimberley Aquaculture Aboriginal Corporation (KAAC) and also the Agriculture Fisheries and Forestry Australia (AFFA) Indigenous Aquaculture Unit (IAU), National Aquaculture Development Strategy for Indigenous Communities in Australia. (PDF contains 13 pages)

Genetic improvement and utilisation of indigenous tilapia in southern Africa: final technical report, December 1st 1998 to June 31st, 2002

Mozambique tilapia (Oreochromis mossambicus) is an indigenous tilapia species in southern Africa, until now the majority of genetic research has been carried out on Asian species of tilapia but this project aims to look at this African species. Those most suited to further development in aquaculture in southern Africa have now been identified. The genetic characterisation of strains has been completed. This information has aided the choice of strains for use in small scale aquaculture and for genetically male tilapia (GMT) production. They will form the basis of future strategies for further genetic improvement, and management of genetic diversity of Mozambique tilapia. The information will also contribute towards responsible management and development of genetic resources, particularly with regard to indigenous species of tilapia. Good progress has been made with the adaptation and implementation of producing the supermale fish required to produce all male offspring, resulting in faster growing populations of tilapia. The presence of the project and its associated activity has been a catalyst for a surge in interest in tilapia culture throughout southern Africa. [PDF contains 183 pages]

Sustainability of indigenous technology in postharvest fisheries operations in Edo and Delta states, Nigeria

The study examined the sustainability of various indigenous technologies in post-harvest fishery operation in Edo and Delta States (Nigeria). A total of seventy processors were interviewed during the survey through a random selection. The data obtained were analysed by descriptive statistics. The results obtained revealed that the majority of the fish processors within the study areas were married with women who were not educated beyond the first Leaving School Certificate. Most of the fish processed were bought fresh, while the commonest method of preservation/processing practiced was smoking. The type of processing equipment used was the Chorkor smoking kiln and the drum smoker while the commonest source of energy is firewood. The processing activities within the communities were found to be profitable. However it was observed that due to the high cost of processing materials and equipment, the economic growth and the living standard is quite low. Some recommendations were made to improve the traditional method of fish preservation and processing

Comment: Food web interactions and biomanipulation in Australian reservoirs

The authors have been studying the control of phytoplankton biomass in several Australian reservoirs. To manipulate fish communities in order to reduce phytoplankton biomass, one needs a thorough understanding of processes in the plankton-associated food webs. In contrast to the situation found in lakes of the northern hemisphere, the planktivorous fish of Australian reservoirs are relatively small and they may deplete small rather than large zooplankters, so that animals as large as the adults of Daphnia carinata may avoid predation. This would result in promotion of Daphnia, particularly if fish eliminate its smaller competitors. The aim of biomanipulation should be the establishment and maintenance of a proper ratio of planktivores/piscivores, adequate for water quality requirements. Successful selection of the appropriate ratio for a given reservoir will depend on the extent of our understanding of its food web interactions. For practical application of biomanipulation in management, further development of the food web theory under Australian conditions is needed.

Evaluation of indigenous molluscicides in water against schistosomiasis vectors

Seven varieties of indigenous Phytolacca dodecwulra L'Herrit (Phytolaccaceae) were field-tried for molluscicidal potency. Varieties (U96) and (U95) collected from Kabarole and Kabale respectively were the most potent with LD90 equal to 2.54 and 6.46 mg.t-· respectively. Water bodies ranging between 4,770 and 347,510 Iitres in Kibimba rice fields were treated with up to 50mg.t-· Snails kills were monitored every three months and 92 - 100% mortality rates were realized. HPLC fingerprints revealed the two P. dodecandra varieties to contain highest concentration of the active principle, oleanoglycotoxin- A or lemmatoxin - A.