Nile tilapia ( Oreochromis niloticus) seed production in irrigated rice-fields in Northwest Bangladesh—an approach appropriate for poorer farmers?

Abstract

Participatory research was conducted with poorer farmers in two communities, Girai ( G) and Bahagili ( B) in NW Bangladesh to assess the production of Nile tilapia seed in irrigated spring rice-fields. All the selected households ( G = 15; B = 4) had previous experience producing common carp ( Cyprinus carpio) in the rice-fields allocated a separate plot in which a deeper area had been excavated for this trial. Mature GIFT strain Nile tilapia (12 female and 6 male; 121 ± 34 g and 158 ± 54 g size, respectively) were supplied to each household irrespective of the size of their trial plot (mean < 0.15 ha). The trial started in the spring rice season ( boro) in February and ended at the end of main season ( amon) in December 1999. Management practices, production and sales of fish were monitored weekly. The majority of farmers succeeded in producing fingerlings in their plots; 11% failed totally but around 70% produced more than 2000 fingerlings from a single plot. Production during boro and fallow period was much higher (> 90% total) than during the subsequent amon crop (< 10% total). Total production was highly variable among households but not different between the two study areas ( G = 4092 ± 3277; B = 3730 ± 4232 fingerlings household − 1 ). Daily production of fingerlings per unit area was relatively low (< 1 fish m − 2 day − 1 ) but efficiency of production was high, averaging 17.3 fingerlings. kg − 1 female day − 1 . Mean individual harvest weight was 21 g. Most fingerlings were sold (43%) and/or stocked for further culture in their own grow-out system (39%), but some were used directly for household consumption (17%).