Nursery rearing of Penaeus monodon (Fabricius) using suspended (hapa) net enclosures installed in a pond

Abstract

The use of suspended (hapa) nets as nursery enclosures for shrimp fry was tested. In the first trial, four stocking densities (72, 144, 288, and 432 fry m⁻³) of P. monodon fry (PL₂₀, body weight = 8 mg, body length = 12.6 mm) were evaluated in 1×1×1.5 m hapa nets. Results showed that shrimp BW, BL, and survival rates were inversely related to stocking density. Shrimp fry stocked at 72 fry m⁻³ attained significantly greater BL of 22 and 37 mm and BW of 50 and 260 mg after 15 and 30 days, respectively, and survival of 92%. A verification trial using PL₂₈ (BW = 10 mg, BL = 13.2 mm) at a stocking density of 288 fry m⁻³ in hapa nets of 2×3×1.5 m yielded a mean survival of 97%, BL 48.1 mm, and BW 780 mg. Hapa nets are therefore useful as alternative shrimp fry nursery systems in the absence of specialized tanks or pond nursery facilities.