06.02.2013 Views

Exotic Aquatic Organisms - International Development Research ...

Exotic Aquatic Organisms - International Development Research ...

Exotic Aquatic Organisms - International Development Research ...

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

104<br />

Pangasius sutchi<br />

Pan gasius sutchi or pangasius catfish was introduced from Thailand in 1969 by Ling (Chen<br />

1976). It cannot tolerate the cooler climate of Taiwan, but it has high tolerance for low oxygen<br />

content. It is quite palatable and larger than the local species of catfish, Clarias fuscus. Also, it<br />

has a very efficient conversion rate, even if it is given only tilapia feed. However, its<br />

acceptability has suffered somewhat because people mistake it for the sea catfish, Anus<br />

maculatus (Thunberg), which closely resembles it in appearance , but which is of much poorer<br />

quality. After its introduction, it was experimentally cultured at a government-run pilot farm. At<br />

present, though, it has come to be used more as an ornamental fish than a food fish.<br />

Clarias batrachus<br />

Clarias batrachus or walking catfish was introduced in 1972 from Thailand (Chen 1976). It<br />

is known for its fast growth rate. One fish can reach up to 2 kg in one year. Although C.<br />

batrachus is also generally regarded as a pest (Welcomme 1984), it has nonetheless achieved<br />

considerable popularity. It has apparently cross-bred with the native species C. fuscus, resulting<br />

in a hybrid that has spread all over Taiwan, to such an extent that C. fuscus is now in danger of<br />

extinction.<br />

0. aureus<br />

0. aureus or blue tilapia was introduced from Israel in 1974 by Liao, Huang and Tseng with<br />

the assistance of Pruginin (Chen 1976; Liao and Chen 1983). The 83 specimens imported were<br />

intended for obtaining all-male offspring when crossed with 0. niloticus females. The resulting<br />

hybrid is now the tilapia mainly cultured in Taiwan; it provides a fine example of success<br />

achieved with exotic aquatic species. Annual production of this hybrid currently.exceeds 50,000<br />

tonnes.<br />

Ictalurus punctatus<br />

Ictalurus punctatus or channel catfish was introduced from the U.S.A. in the mid 70's.<br />

However, the warmer climate in Taiwan is not very suitable for its culture. It is also very<br />

sensitive to water quality, such as that resulting from pollution. Not being so popular, this<br />

species is no longer cultured.<br />

Anguilla anguilla<br />

Anguilla anguilla or European or French eel was introduced to Taiwan around 1976 (Chen<br />

1976). It is native to Europe and at the time of its introduction, it was considered as a promising<br />

species for culture. Although A. japonica, the native species, is a good culture species, and the<br />

technology for raising it was well understood by the local aquaculturists, the inability to produce<br />

adequate quantities of this species prompted the introduction of A. anguilla.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!