Mosquito nets used for fishing are killing Africa’s aqua life

THE ANTI-malaria campaign supported by Bill and Melinda Gates and US president Barack Obama( Cape Argus, June 9) is worthwhile as more than 437 000 African children under the age of five died from malaria in 2013.

However, I wonder whether the benefactors of this campaign are aware that one of the methods they use – the free or discounted distribution of mosquito nets – has had a negative impact on African freshwaters and on the livelihoods of millions of rural African people.

These nets are not used to protect people from mosquitoes but as fine-mesh seine nets or lift nets to catch fish in shallow water or over deep water. In addition, since the 1990s, mosquito nets have been used to line constriction fish traps throughout tropical Africa.

As many of these mosquito nets are impregnated with insecticides, especially Deltamethrin, they cause mass mortalities among fish and other aquatic organisms and also accumulate up the food chain. Mosquito nets pose an additional threat to fish stocks as their fine mesh catches both small, pre-breeding fish and large, adult fish, as well as insects, snails, frogs and even reptiles.

In many areas these nets have now replaced traditional seine and lift nets that are made from natural, biodegradable materials (and do not contain insecticides). In my recent book Traditional

Fishing Methods of Africa, I list poisoning together with monofilament gillnets, blast fishing and ghost fishing as the most significant threats facing African freshwater fisheries, which feed millions of people annually. MIKE BRUTON Rondebosch