author(s)
Md. Ekramul Hasan, AK Jilani Chowdhury and Md. Golam Sarwer

abstract
A study was conducted to observe the breeding and seed production techniques of endangered giant river catfish, Sperata seenghala, locally known as “guizza air’’. In this study, a total of 60 pairs of adult guizza air (850-1500 g) were collected from the Brahmaputra river-basin and floodplains in Mymensingh region and stocked in a 40 decimal pond with 2.5-3 feet depth three months before the onset of the breeding season. Hatchlings gradually started to consume zooplanktons available in the spawning pond and no artificial feeds were used. Fry numbering 50,280 with a mean ± SD length and weight of 1.91 ± 0.24 cm and 0.25 ± 0.07 g, respectively were collected by repeated netting with mosquito net from the spawning pond after 15 days of spawning. The fry were then stocked at 1000 fry/dec in two earthen nursery ponds having area of 20 and 30 decimal with an average depth of 3 feet. Fry in two nursery ponds were reared with commercial nursery feed for the first 14 days and pre-starter feed during days 15-28. The water temperature in the nursery ponds was ranged from 30.53 ± 0.71 to 32.85 ± 0.49 oC during nursing. The values of dissolve oxygen (DO) and pH ranged from 6.50 ± 0.41 to 4.27 ± 0.71 ppm and 7.8 ± 0.62 to 7.2 ± 0.47, respectively. The final average length and weight of the fingerlings were 6.26 ± 0.21 cm and 2.55 ± 0.08 g, respectively after four weeks of nursing. The survival rate of fry was 63% with a net production was 630 fry/dec. It can be concluded that the captive breeding and seed production techniques of S. seenghala described here is an important step in conservation and pond culture of the endangered S. seenghala.