KONINKLIJKE ACADEMIE VOOR OVERZEESE WETENSCHAPPEN ...

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3.1.4. Fish Reproduction Characteristics
As reported, climbing perch matures after five or six months at 8-10 cm
( P o t o n g k a m 1971) or after twelve months at 10-12 cm ( Y en 1983, T r u n g 1999).
In natural condition, fish moves upstream in small canals for reproduction ( K h oa
& H u o n g 1982, Y e n 1983). Females are larger with a head bigger than males
whose body colour is never yellow as females (figs. 6 , 8). Climbing perch can
spawn many times a year. Spawning season is from April to September but
optimum in June. Fecundity ranges from 300,000-700,000 eggs/kg. Eggs are
slight white or slight yellow. The diameter of eggs ovulated ranges from 1.1-1.2
mm (fig. 7). They are pelagic, floating at the water surface. Recently, climbing
perch has become one of the most important cultured fish species in the Mekong
Delta. But the wild fingerlings were still the main source for various cultured
systems. Therefore, lack of fingerlings is the main constraint for the development
of this fish farming. That is why we have tried to improve fingerlings’ supply
through artificial propagation.
Fig. 6. — Female of climbing perch.
Fig. 7. — Ovary of climbing perch female.