442 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1962 



trepha hidens (Loew)), after following air currents across deserts 

 for more than 100 miles each year, invades the lower Eio Grande 

 Valley of Texas, where it causes an annoying quarantine problem. 

 The oriental and other fruit flies may fly from one Pacific island to 

 another, sometimes across 35 miles or more of open sea. 



The losses caused by tropical fruit-fly larvae as they feed and live 

 in the fruits of host plants accord these flies high rank among the 

 world's foremost plant pests. Well known is the Mediterranean fruit 

 fly {Ceratitis capitata (Weidemann) ), which has invaded our country 

 three times within the span of the last four decades. Eradication in 

 1929-30 cost about $71/2 million plus many million pounds of citrus 

 that was destroyed to eliminate breeding. In 1956-57 this fly's 

 elimination cost nearly $11 million. In 1962 early detection with 

 strong lures developed by research reduced the cost of another eradi- 

 cation campaign, which appears to have been successful, to less than $2 

 million. The olive fruit fly {Dacus oleae (Gmelin)) takes a toll of 

 nearly a third of all olives produced on countless trees in the Medi- 

 terranean area each year. AVlien we consider that olives and olive 

 oil comprise a substantial part of the caloric intake of people living 

 there, and that Greece alone has an estimated 75 million olive trees, 

 this loss is indeed appalling. In every continent — Africa, Asia, Aus- 

 tralia, Europe, North America, and South America — tropical fruit 

 flies are obstacles to efficient fruit and vegetable production. 



What to do about tropical fruit flies and how to detect mvasion by 

 them are problems that have received serious attention by research 

 scientists and farmers for a long time. Probably one of the earliest 

 control measures was the use of fermenting juices or wine in bottle 

 traps, which attracted some of the flies. After entering the traps, 

 they fell into the liquid and were drowned. Such lures were never 

 very successful, even though trap designs and formulations were 

 gradually improved. 



In another early control procedure, materials that the flies like to 

 eat were mixed with poisons. The first of these poisoned baits were 

 developed in Italy and South Africa. The bait materials were usually 

 sweet substances such as brown sugar or molasses, or fermenting 

 wheat bran. The most effective toxicants for use with them were 

 arsenicals or other inorganic compounds. Unfortunately, mixtures 

 such as these were often harmful to foliage or left excessive residues 

 on the ripening fruit. Sometimes they were applied to cut sprigs 

 of foliage from other trees, or on tied-up bunches of weeds of broom- 

 straw, which, after treatment, were suspended in the canopies or host 

 trees to be protected. This poisoned-bait method, known as the 

 Berlese method after the Italian scientist who first used it in olive 

 orchards in an attempt to control the olive fly, was also only partially 

 successful. 



