Rare "Aquarium" Fish Risk Extinction

Just 15 years ago, villagers near the southern tip of Lake Malawi helped save the mbuna from extinction by not cutting firewood for fuel. Researchers said that soil erosion was washing silt into the lake. This accumulated on the rocks where the mbuna lived and killed the algae on which the fish lived.

Now a new study by scientists has shown that the same villagers of Chembe -- Malawi's largest fishing village, lying at the tip of the Cape Maclear peninsula -- are turning to mbuna and other rare fish to meet the greater food demands of the growing population.

The population of Chembe has increased from 555 in 1910 to 4,671 in 1992. This, the study said, has "greatly increased the nutritional demands of the village."

"Lake Malawi's fish fauna is unique and boasts the highest species diversity of any lake in the world, but conservation must be balanced with meeting the nutritional requirements of a rapidly growing population," researcher Mike Tweddle said in the study.

About 75,000 tons of fish, with a value of $2 million are caught in the various lakes throughout the country each year.

The ecological importance of the mbuna led the government to designate the area around Cape Maclear as the Lake Malawi National Park. The park, which includes 87 square kilometers of land with a water portion extending 100 meters from the shore, was declared a world heritage site by the United Nations Educational Scientific and Cultural Organization (UNESCO) in 1984 in recognition of its ecological importance.

Mbuna rarely grow larger than 15 centimeters and the design of their teeth is different in each fish, allowing them to eat off of different parts of the same algae.

"Far more fish are being caught by Chembe fishermen than can be consumed in the village. Hence increases in the numbers of fishermen magnifies fish exploitation more than is immediately apparent," says the study.

"The exploitation with gill nets of previously unfished species such as Usipa and certain Utaka species has allowed these villages to grow more rapidly than the national average in the last 30 years," the study said.

Nets previously had a minimum mesh size of 89 millimeters but as the competition for fish has become fiercer, smaller nets are being used.

Legislation bans the catching of fish until they have had a chance to breed. Fish less than 15 centimeters long must be returned to the water alive, but the laws are largely ignored and do not deter offenders.

The study suggests that the dual park objectives of conservation and sustainable yield of fish stocks can only be realized through close regulation and proper management of the village fishery. It said that the common practice of catching breeding and sexually immature fish eventually destroys stocks, forcing the fishery to seek new ones.

The population growth of the villages mirrors that of the country. Malawi's population has grown at 3.5 percent each year, from four million at independence in 1964 to nearly 10 million in 1994.

Cichlidae fish are extremely popular among aquarium owners and fish breeders all over the world; they have become part of the international trade in ornamental fish.

In 1995, Malawi exported $340,000 worth of aquarium fish to Germany, France, Belgium, North America, and other European countries.