On The Ground in Malawi: Overfishing

Balancing nature conservation and human wellbeing

Due to overfishing, the fish populations in Lake Malawi are declining dramatically. If the present trend continues, the whole colourful diversity of cichlid fishes may be completely gone in a few decades. 

Declining populations

The issue with declining fish populations in Lake Malawi is not just an ordinary case of a few fish species being threatened. “In terms of threatened, the whole lake is threatened”, sighs Dr. Ken McKaye, who has been studying the cichlids of Lake Malawi since the 1970’s.

Ken has seen changes over the years. In the late 1970’s and in the early 1980’s, a fisherman could get 50–60 fish species with a half-hour trawl. Now the fish populations have collapsed.

In addition to fewer fish and species being caught, there is also a change in the size of some fish. The catfish kampango (Bagrus meridionalis) used to reach a length of more than one metre (about four feet). Nowadays one seldom sees a kampango bigger than half a metre (less than two feet), because the fish get caught before they grow to reach a bigger size.

Overeffective nets and fish poaching

Part of the problem relates to commercial large-scale fishermen with their efficient trawlers. But small-scale fishing is often unsustainable too.

Some small-scale fishermen use nets with a small mesh-size, catching young fish before they are mature enough to reproduce. Some fishermen even use mosquito nets, while other nets can reach a length of four kilometres. This results in virtually everything being scooped up in the net’s trajectory. Fishermen are now going to deeper waters, since not many fish remain in the shallow areas.

Fish poaching is part of the problem. No-fishing zones have been established to give the fish some safe breeding areas, but frequently this measure is not respected.

Potential future threats

Despite the diminishing populations, the situation does not look as bad in terms of extinction – yet. Ken estimates that one or two fish species in the lake may have become extinct due to overfishing but concedes that the same could also easily happen to many other species.

Many of the species live in a very small area, which makes them more vulnerable. Ken predicts that a fuel spill on one of the islands would be enough to drive 30–40 species to extinction.

A new potential threat may be an oil field that has been found in northern Malawi. Whether it will be exploited depends on the amount there is. Transporting oil via the lake could lead to a huge disaster in the event of an accident. This worries Ken, who feels that people should understand that the fresh water is worth more than the oil.

With its beautiful scenery, sandy beaches and a colourful fish world for snorklers and scuba divers to enjoy, the lake provides considerable opportunities for tourism, if the water stays clean and the fish continue to thrive. The lake also provides an ultimate source of water for agriculture throughout Southern Africa.

Reasons for optimism

Ken is actively involved in the WWF Finland conservation project to save the cichlid diversity in Malawi. He says it is not too late yet and refers to Britain, where salmon are now again swimming up Thames. The environment can recover.

Indeed, with Lake Malawi, there are many reasons for optimism. There are no introduced fish species in the lake, and no major chemical production around it. The fishes are still there. The example with Lake Malawi National Park has shown that fish populations do recover in protected areas. Even some of the most over-exploited species have spread back to areas that have been effectively protected.