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Table Of Contents
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Volume 19, Number 1/Winter 2004 pdacrsp.oregonstate.edu ISSN 1062-4996
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Sustainable Aquaculture
for a Secure Future
Aquaculture Collaborative Research Support Program Newsletter

Climbing Perch
(Anabas testudineus)


The climbing perch (
Anabas testudineus) is a fish of tropical fresh waters of Asia and the Far East. The fish derives its name from the widely held belief that it can climb on trees, but this is actually a result of faulty observation.
A. testudineus is a very hardy fish. It is mostly caught from swampy and marshy tracts, as well as derelict pits, pools, and puddles that continue drying up during summer months. In its natural habitat, the fish can "walk" over dry land for some distance using its operculum and pectoral fins.
A. testudineus is in the family Anabantidae. It has an elongated body, with broad anterior and head, while the posterior is compressed. The dorsal side, and dorsal and caudal fins, are greenish to dark grey, while the belly, pectoral, and anal fins are pale yellow-colored. At the base of the caudal fin, a dark spot is present. A. testudineus is an obligatory air-breathing fish. In addition to four pairs of gills, it bears accessory respiratory organs‹one pair of labyrinthine and respiratory membranes within the suprabranchial chamber. The fish is highly esteemed for its fine flavor and prolonged freshness out of water. The maximum recorded length is 26 cm.
Seed of A. testudineus can be collected
from nature or obtained under controlled conditions. A. testudineus is notorious for migrating and breeding into prepared carp nurseries. This habit is advantageously used for seed production. Gonad maturity in A. testudineus manifests with early rains, and the retrogression is noticed abruptly from September. Breeding takes place only after rain fully sets in and fills ditches. According to Besra (1997), breeding season lasts between the middle of April to the
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New Fish Species Studied for Aquaculture Potential by Aquaculture CRSP Researchers
By Dhirendra Prasad Thakur, Asian Institute of Technology

(Editor's note: This is the last article in a series discussing detailed aspects of biology of three fish species being studied for aquaculture potential.)
Climbing Perch (Anabas testudineus)
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. . .continued on p. 6
. . .continued on p. 3
Small-Scale Fish Farming is Picking Up as an Enterprise in Kenya
By Charles Ngugi, Moi University; and James Bowman, Oregon State University

Small-scale fish farming has had many false starts in sub-Saharan Africa, dating back to the beginning of the twentieth century. Pessimists still consider aquaculture to be a risky enterprise and argue that it will take a long time for farmers to adopt the technology of pond fish production. They advance reasons such as lack of experience in fish breeding and poor economic returns to cash and labor investments, coupled with poor fish yields. Efforts to increase production from small-scale pond aquaculture have focused primarily on increasing either the surface area or the yield per area of ponds already in use. Such efforts have been receiving financial aid from donor agencies and other institutions to supplement the modest support coming from the states and governments.
Fish farming in Kenya has a history of more than 50 years, yet the culture of tilapia and catfish remains primarily at the subsistence level. The potential for economically viable and sustainable commercial aquaculture has remained largely unrealized—ponds produce low yields, limited by the natural carrying capacity of the water body. Recently however, we have witnessed changes as some small-scale fish farmers have begun turning subsistence aquaculture into profitable small-scale enterprises. The widespread adoption of up-to-date fish farming technologies, especially
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middle of June. In the laboratory, end of breeding was delayed as late as September. Induced breeding by hypophysation was successfully performed. Water temperature of 28 ± 1oC and darkness were important environmental factors for successful spawning. A female weighing about 50 g produces about 20,000 eggs. Eggs float in an upside-down position at the surface. Feeding commences from the second day. Ciliates, flagellates, and other such minute zooplankton form the chief food of food of larvae at this stage.

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