WHITE BUTTERFLIES

New Zealand Herald, Volume LXXI, Issue 21938, 23 October 1934, Page 11

WHITE BUTTERFLIES

DIMINUTION OF PEST

DECREASE IN HAWKE'S BAY PARASITES' GOOD WORK Two years ago the Hawke's Bay Agricultural and Pastoral Association offered a prize to the boy or girl who caught the largest number of white butterflies. The winner had something like 70,000 to his credit, but were the lad to try again to-day he would not get within cooee of that tally, says the Manauatu Times. The decrease in the butterflies.is the direct result of the work of the Department of Agriculture in liberating a vast army of parasites. The raids of these tiny insects have been responsible for a remarkable diminution of the pest in Hawke's Bay. In fact, according to Mr. J. Muggeridge, of the Palmerston North Plant' Research Station, who has had charge of the breeding and liberation of the parasites, there are more white butterflies to be seen in Palmerston North at present than in the vicinity of Hastings.

Mr. Muggeridge has returned from Hawke's Bay, where he has been conducting field investigations into the spread of the parasites. He says he is more than pleased with the results secured so far, but adds that one must not infer from this that the necessary degree of control has been secured. He will not be able to determine that until the latter end of the summer. Hawke's Bay is still likely to see something of the butterfly, and in spite of the presence of the pupal parasite there are likely to be local infections, i.e., the butterfly is likely to get away again in isolated patches. Throughout the coming season surveys will be made and proper counts kept so that at the end of the summer there will be definite information as to the progress that has been made. During the last five or six months the department has been breeding additional parasites for distribution, but these will not be released until the end of December and in January, because it is essential to liberate them in localities whefe there is a plentiful supply of hosts and so give them a chance to become established. Mr. Muggeridge has now about 40,000 parasitised butterfly chrysalids in cool storage, and from these he anticipates raising from 600,000 to 800,000 parasites. A large number of requests for supplies has been received, and as the number , to be raised is not sufficient to meet all requirements, the department will be able to distribute them only in the more thickly infested areas.