Study of a shallow carp (Cyprinus carpio L.) pond and its relevance to inland fish farming in Libyan Jamahiriya

Adult mirror carp (Cyprinus carpio), put into a small artificial pond (area 30 m²; volume about 6.5 m³) in the Al-Fateh University campus, in Tripoli, Libya, in autumn 1977, consumed all molluscs and higher plants and were feeding on Cyanophyta (Coelosphaerium and Lyngbia) prior to spawning in May 1978. The young grew to 136 mm fork length and yielded 2.2 kg (live weight) in 14 months (62.8 g/m² per year) without food or fertilisers being added. They stayed under cover for five winter months and at this time growth was not affected much. Quantitative or semi-quantitative data are given for water depths, salinity balance, maximum and minimum water and other temperatures, solar radiation, and for biomass of producer and consumer species, together with observations on algal species, carp and goldfish (Carassius auratus).