DEATH TO MOSQUITOES

Taupo Times, Volume I, Issue 35, 10 September 1952, Page 5

DEATH TO MOSQUITOES

FEROCIOOS LITTLE FISH In a talk in the "Eye-Witness" programme of the B.B.C. some time ago Norman Marshail deciibed a 1'ish that is being used to keep down mosquitoes. "The Gambusia," he said, "originally came from the swamps and streams of the Americas — North and South. At its biggest, it is only two or three inches long, but it is one of the most ferocious fish there is. Put a couple of them into a tank with, for example, goldfsh, and they will just wade into the goldfish. They will even nip off the ends of a water snail's horns, and they do not give any warning of attack — they just dart in. It is one of the fish that gives birth to its young: it Joes not spawn or lay eggs. And apparently the newly born Gambusia are very much alive to the possibility of being snapped up and swallowed by their parents, or any other adult Gambusia in their immediate neighbourhood, because immediately they are born they dive for cover into scme crevice, and stay there until they have grown too large to be swal-lowed whole. "When the Gambusia was first put on the market for aquaria, it was adverth cd as 'the eighth wonder of the world/ The fish with the viciet eye/ "the fish that produces up to forty at a time/ But it was very soon found that they kill each other off when kept in close captivity. Their favourite food is the larvae of insects, and among the larvae they devour is that of the mosquito. They seem to be aii ideal weapon in the battle against the mosquito, and they are being used most successfully in this battle. In fact, this little fish not only helped to keep malaria and yellow fever down during the building of the Panama Canal, but it has belped to make the Panama Isthmus habitable. And it is doing good work in keeping mosquitoes down in parts of Spain, India, Tunisia and other parts of Africa. "Some years ago a few pairs were released in the swamps at the River Tweed in New South Wales. Soon there were thousands of them; but then a school of twenty will multiply to 3,000 in six months. Gambusia proved so successful in keeping mosquitoes down that batches of them were liberated at one place after another. It is being used in mosquito-infested swamps which for one reason or another it would prove impossible, or too expensive, to drain. Fortunately, it is seldom attacked by disease, and does not seem to have many enemies. It is its own worst enemy, for there would be ;millions more Gambusia if they did not kill each other off way they do."