Over 100 fresh water fish (Betta sp.) which were bred in the programme “Breeding and release of native fish back to nature” from Wildlife At Risk (WAR) were released into the canal under the Red Bridge (Cau Do), a tributary of the Saigon River. Participated in the releasing activity are more than 20 people including members of the club “I love Nature”, Red scarf Magazine (aged 12-15), and volunteers who are university students from Ho Chi Minh City.
Individual numbers of many species of fresh water fish are steadily reducing due to water pollution. Fish that are not exploited for commercial purposes do not get enough attention, even though they are disappearing. This is a great loss to the ecosystem and species diversity in Vietnam.
In order to maintain this genetic diversity and the natural balance, WAR has been conducting a survey on these non-commercial native species in order to breed and release them into the wild since February. Many of these fish can be used as ornamentals. Species in this programme include the Crescent betta, Lambchop rasbora, Blackline rasbora, and Pygmy gourami. These species were collected during WAR’s survey programme in Lam Dong and Dong Nai provinces, Phu Quoc island, and U Minh Thuong National Park.
Most of the ornamental fish and lucky fish released in Ho Chi Minh City and other big cities in Vietnam are imported. After a while, these fish are released or escape to the wild and become invasive species, or species that compete with the native ones. WAR encourages the use of native fish for ornamental fish and the release of these species because they do not disturb the ecosystem when released to the wild.
These Beta species that are distributed in the south of Vietnam are able to tolerate water with lower oxygen and pollution thanks to their ability to absorb oxygen from the air. They can also survive in the polluted waters where no other fish species can survive. In addition, the favourite food of this species is small animals, especially mosquito larva. Some decades ago, this species was quite common in the inner and outer areas of Ho Chi Minh City. However, together with urbanisation, the habitat of these species including canals, marshes, and ponds have been lost. Additionally, the water is so polluted that these species become very rare in the city.
“The breeding and release of these fish to the wild not only helps to improve the population of the native fish in the basin of the Saigon River, but also helps to reduce mosquito larva and thus the mosquito, including those causing dengue fever and other diseases” said Mr. Bui Huu Manh, Senior Conservation Officer, WAR.
This activity of releasing fish helps the students to understand the importance of native species protection. It also directs the students toward environment protection through their daily activities. Before releasing the fish, the students also collected all the garbage at the site.
In the future, WAR will continue the programme of breeding and release of native fish species that are not exploited for commercial purposes but can be used for aquariums.
Photos of the releasing fish activity can be viewed here.