THE FLIGHT OF TWO THOUSAND MARKED MALE’ 
MEDITERRANEAN FRUIT FLIES (CERATITIS 
CAPITATA WIED.). 
Henry H. P. SEVERIN, Ph. D., Honorary Fellow, University of Wisconsin, and 
WILLIAM J. HARTUNG, B. S. 
Mally (1, p. 8) Entomologist for the Eastern Province, Cape: 
Colony, South Africa, discusses the migration of the adult 
Mediterranean fruit fly as follows: ‘‘There is no evidence to: 
show how far the adults will travel in their search for food. 
Some observers think they migrate but very little, citing: 
instances where well-kept premises have been fairly free although 
in close proximity to neglected and badly infested ones. Under 
such conditions there is no necessity for migration, ample food- 
supply being already at hand. ‘There is no clear evidence to 
show how they get to new orchards on farms where fruit trees. 
have never been grown before. Men who have laid out new 
orchards say that the ‘maggot’ was in evidence the first time the 
trees came into bearing. * * * It is a popular belief that the 
flies come in from the veld. The most unrelenting search has 
failed to demonstrate their presence in bush or veld 500 yang 
from an orchard.”’ 
‘Prevailing winds are perhaps the most potent factor. How 
far the flies are liable to be carried by the wind it is impossible: 
to say. One would hardly expect that they would be blown 
very far at once. It seems easily within the range of posst- 
bility that they should be involuntarily caught up by the wind 
when they attempt to fly and lodge on a bush or in the veld 
some distance away; and then be caught up again and carried 
still farther, and so on indefinitely. There is little doubt that 
certain Aphidide do make use of the wind in migrating to their 
secondary host plant, but I have found nothing to indicate the 
presence of the same trait in the fruit fly.”’ 
Newman 2, (p. 7) Entomologist of Western Australia writes 
as follows concerning the migration of the Mediterranean fruit 
fly: ‘‘This fly is not an insect that migrates any great distance. 
As long as a food supply is available, it remains in an orchard. 
I have known instances where one orchard was swarming with 
the pest and the one next door or on the opposite side of the 
street was perfectly clean. Strong winds are the most potent 
factor in the spread of the fly ; there is no saying how far she 
may be carried.”’ 
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