VietNamNet Bridge 20 May 12;
Anh Vu (Semilabeo notabilis), Mang (Chanos chanos), Ca Lo, (Cyprinus multitaeniata), ram xanh (Altigena lemassoni Pellegrin et Chevey) and many other rare precious fishes have been named in the Vietnam’s Red Book, because their existence has been threatened.
Dat Viet cited a report by Dr Mai Dinh Yen, Deputy Chair of the Vietnam Ecology Association, as reported that the wild fish catching volume on the Gam River was about 300 tons per annum. However, the exploited output has been decreasing sharply.
A survey conducted by the Institute of Ecology and Biological Resources also found out that Anh Vu fish (Semilabeo notabilis), a kind of precious fish, has still been living on the Gam river, but the volume is very modest. The output of the fish has dropped by 70 percent in comparison with the exploited volume in 1970 or 1971.
Besides, Ca Lang (Hemibagrus elongatus), Ca Chien (Bagarius) and ram xanh (Altigena lemassoni Pellegrin et Chevey), which all have high economic value, have also got exhausted because of the massive exploitation.
If going along the riverside in the upper area (Bao Lac and Bao Lam districts of Cao Bang province), one would see a lot of fishing boats with different tools for catching fish, waiting on every section of river for the opportunities to catch up fish.
Local residents would use everything they can to catch fish, from net, cages to electricity and chemicals.
Dr Le Hung Anh from a team which is making a research work on the diversification of the aquatic creatures on the Gam River in the northwest of Vietnam, said that the quality of the Gam river’s water has been downgrading seriously due to the afforestation, gold and sand exploitation, hydropower plants’ water reservoir building and the urban area development.
A lot of rare and precious fishes on the river, which once brought big benefits to local residents, have got exhausted because of the people’s industrial production.
The Gam River originates from China. Its total length is 297 kilometers, while the section or river running across the Vietnamese territory (Cao Bang, Ha Giang and Tuyen Quang provinces) is 217 kilometers.
Though scientists can anticipate the bad consequences of the activities of exploiting sand, chopping the forest on the environment, there have been not many research works about the aquatic creatures on the Gam River and the operation of the Tuyen Quang hydropower plant water reservoir recently. The documents about the habitat, the spawning grounds, and the living areas of precious fishes are still lacking. Especially, there has been no survey about the living environment of the Gam River in the Na Hang and Chiem Hoa areas after the water reservoir was set up.
Scientists have pointed out that the protection and management over the natural resources on the Gam River and Tuyen Quang hydropower reservoir system have not got the appropriate attention.
Local authorities have geared up in their plans to rescue and protect rare precious fishes in their localities.
Local newspapers have quoted Nguyen Thi Ngoc Trinh, Director of the An Giang provincial Aquatic Breeder Center, as saying that the center has successfully created 30,000 ca ho (Catlocarpio siamensis) individuals, paving the way for the protection and conservation of the rare fish.
A Ca ho, with white and delicious meat, weights 50-100 kilos. The products are selling at 400,000 per kilo. However, the supply still cannot satisfy the demand, and the products are not available on the market because they are collected all by restaurants and hotels.
C. V
