File under win-win: research in Kenya shows that by raising tilapia, locals can reduce the population of a malaria-carrying mosquito (by a whopping 94%), then harvest the fish for the dinner table.
Spurred by the growing incidence of pesticide resistance among mosquitoes, the researchers began looking for nonchemical ways to kill the mosquitoes’ buzz. Mosquitoes spend their larval lives wiggling around in pools of water, gobbling microorganisms and hiding out in the foliage. Tilapia seem to go after them using something of a tiered approach: larger fish nibble on aquatic plants, depriving larvae of hiding places; and the tilapia fry go right after the larvae themselves. Apparently, people postulated a century ago that hungry fish should be useful malaria-fighters, but no one had checked it out numerically.
It’s interesting that many Kenyans already farm tilapia (which are native to the Nile), leading one to wonder why existing tiliapia farms haven’t knocked down the malaria problem yet. (The town the researchers studied records 2,200 malaria cases per year; globally, more than 350 million people get malaria each year, and 1 million die.)
Chalk it up to business misfortunes: when a farming operation goes under, the abandoned fishponds collect water and breed hordes of mosquitoes. The prospect of restocking those ponds and at the same time clearing them of mosquitoes suggests a worthwhile place to invest development funds.
Image: a cool stamp collection