The coconut moth was a devastating pest in Fiji in the 1920s. It was known to havebeen introduced in 1900 but no-one knew where it had been introduced from. Itwas thought that the coconut moth might have originated from the larger island VitiLevu, where coconut could not be grown because of the moth. However, whenViti Levu was searched, no natural enemies were found. (Actually, since this earlyprogram, our thinking has changed and researchers would now assume that if a pestwas out of control in an area, that was probably not where it originated because inits area of endemism, the natural enemies would keep the pest population densitieslow.) Further South Pacific islands were searched but the coconut moth was notfound on any other island.Eventually, the frustrated researchers decided to try parasitoids and predatorsattacking related moth species from throughout the southeastern Pacific. At anoutbreak of the related moth species Cathartona catoxantha near Kuala Lumpur in1925, both wasp and fly parasitoids were found attacking coconut moth caterpillars.Four large cages were constructed and filled with 85 young palm trees hosting20,000 parasitized and unparasitized moth larvae. These cages traveled by rail toSingapore and then were on board a ship headed for Fiji for 25 more days. By thetime the cages were opened in the quarantine in Fiji, no wasps had survived buta total of 315 individuals of the parasitic fly Bessa remota were still alive. Thesetachinid flies were easy to rear on caterpillars and by 1926, 15,000 flies had beenreleased in coconut-palm-growing areas. These flies did a great job of controllingcoconut moth and even proceeded to disperse throughout Fiji on their own. In
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