The Luapula Province of northern Zambia falls within the Mweru-Luapula freshwater ecoregion and is characterised by a high diversity of fish species due to the influence of the Zambezian and Congolian fauna. Rainfall in the province can be as high as 1111 mm per annum, and the many wetlands and small streams create ideal agro-ecological conditions for dug-out and furrow-fed fishponds, which are often integrated into vegetable horticulture with basic irrigation. Ponds are small, ranging from 40-600 m2, and usually shallow (40-120 cm deep).
During preliminary field work of the Fish for Food Security in Zambia Project, a sample of 20 established fish farms were visited in Kawambwa, Mwense and Mansa Districts, from early 2020 to late 2021. Ponds were sampled with a cast net and fish were placed into a bucket for identification and photographed.
A total of 17 species were recorded across the 20 farms, dominated by the family Cichlidae (11 species), followed by catfishes and cyprinids. Of the 17 species, only eight were recorded as having been purposely stocked, while the rest had colonised ponds from the wild. Despite the wide diversity of fish species identified across the sites, three-quarters (76%) of the diversity was infrequently encountered (only 1-2 sites). Only four species were frequently encountered: Coptodon rendalli (100%), Tilapia sparrmanii (90%), Oreochromis niloticus ( 65%) and O. mweruensis/macrochir (45%) . This study also presents the first documented record of the poorly known but entirely Zambian-endemic Kawambwa tilapia (Tilapia baloni ) from aquaculture ponds.
We also present how these results informed farmer trainings on fish identification and polyculture for optimising trophic use of the pond environment and maximising nutritional yields.
Keywords:
*Polyculture*Tilapia diversity*Trophic niche efficiency*Zambia*Smallholder aquaculture*