Cite as: [Author(s), 2001. Title.] In: A. Gupta, K. McElwee, D. Burke, J. Burright, X. Cummings, and H. Egna (Editors), Eighteenth Annual Technical Report. Pond Dynamics/Aquaculture CRSP, Oregon State University, Corvallis, Oregon, [pp. ___.]

Culture of Mixed-Sex Nile Tilapia with Predatory Snakehead

Ninth Work Plan, New Aquaculture Systems/New Species Research 2 (9NS2)
Abstract

C. Kwei Lin and Yang Yi
Aquaculture and Aquatic Resources Management Program
Asian Institute of Technology
Pathumthani, Thailand

James S. Diana
School of Natural Resources and Environment
The University of Michigan
Ann Arbor, Michigan, USA

Abstract

An experiment was conducted in eighteen 200-m² earthen ponds at the Asian Institute of Technology, Thailand, during May through October 1999. The purposes of the experiment were to: 1) assess the efficiency of snakehead (Channa striata) in controlling overpopulation of mixed-sex Nile tilapia (Oreochromis niloticus) in ponds and 2) assess growth and production characteristics of Nile tilapia in monoculture and polyculture with snakehead. The six treatments were: A) monoculture of sex-reversed tilapia; B) monoculture of mixed-sex tilapia; C) polyculture of mixed-sex tilapia and snakehead at 10:1 ratio; D) polyculture of mixed-sex tilapia and snakehead at 20:1 ratio; E) polyculture of mixed-sex tilapia and snakehead at 40:1 ratio; and F) polyculture of mixed-sex tilapia and snakehead at 80:1 ratio. All ponds were fertilized weekly with urea and triple superphosphate (TSP) at rates of 28 kg N and 7 kg P ha^-1 wk^-1. Sex-reversed all-male and mixed-sex Nile tilapia were stocked at 2 fish m^-2 at sizes of 42.3 ± 1.0 g and 31.0 ± 0.5 g, respectively. Snakehead dug holes in the pond dikes and moved freely between ponds and the canal. The experiment showed that snakehead can control overpopulation of mixed-sex Nile tilapia. This experiment is currently being repeated, starting in March 2000 and terminating in September 2000.