o_19ko2dt161ng2j4e1tgnoqv1s45a.pdf

A. AHMAD & A.R. KHAIRUL-ADHA (2007)
FRESHWATER FISHES OF SABAH AND SARAWAK
Sabah and Sarawak has perhaps over 100 and 200 species, respectively. It is difficult to
provide a close estimate of the diversity as many studies are still in progress or about to begin.
Therefore, the figures currently available for Sabah and Sarawak are poor estimates. The two
states are believed to harbor more than what we currently know of their ichthyofauna diversity.
This low number merely reflects the lack of inventory studies. For Sabah, Chin (1990) listed
the number of freshwater fish species ca. 155, including 12 exotic species. Martin-Smith &
Tan (1998) acknowledged that the true number of freshwater fishes in Sabah is probably
much higher.
Sabah is probably better known for its freshwater fish diversity based on the work of Robert
F. Inger & P. K. Chin, the Freshwater Fishes of North Borneo (1962) and a subsequent
supplementary chapter in 1990 (Inger & Chin 1990). Apart from this, there were no other
major taxonomical studies/revisions nor were there many comprehensive collections made—
much of the research in the state were ecological in approach. Specialist collections at localized
areas however, yielded interesting results (Chin & Samat 1992, Chin & Samat 1995). Work
by Martin-Smith & Tan (1998) has significantly contributed to the understanding of
ichthyofauna in eastern Sabah. Two new species of the genus Gastromyzon had been described
recently (Tan & Martin-Smith 1998).
Unlike Sabah, the freshwater fishes of Sarawak have never been the subject of any major
research endeavor. Scattered studies were conducted mainly on documenting the fish fauna
that were affected by development as part of the requirement of Environmental Impact
Assessment (EIA). Again, focus was given to major rivers in the state and many isolated and
inland water bodies were left unexplored. Watson & Balon (1984) conducted a survey along
the Baram River but much of the associated taxonomic work was ignored. The listing of
species that occurred in the River drainage, including those that occurred in Brunei, can be
found in Kottelat & Lim (1995). This listing is probably the only major publication for the
state of Sarawak. Several new species including a Rasbora, a freshwater puffer fish and an
anabantoids fish had been described in the last decade from the state.
AREAS WITH KNOWN DIVERSITY
Previous studies on the freshwater fishes of Peninsular Malaysia were mainly conducted at
Taman Negara (King Edward’s National Park) (Zakaria-Ismail 1984, Tan & Hamzah 1990).
Following this, at least four major rivers were surveyed and among them, only Sungai Pahang
can be regarded as being thoroughly surveyed (Khan et al. 1996) and the fish collection properly
catalogued and identified to the taxon level!
Fish survey along a tributary of Sungai Terengganu was made prior to the construction of the
Kenyir hydroelectric dam more than two decades ago. Cramphorn (1983) visited several sites
and the materials collected might be available elsewhere. The fish diversity along Sungai
Perak and Sungai Kelantan have been documented by T.I. Kvernevik but these are not complete.
A major gap is recognized and a more thorough survey is urgently required.
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