Mediterranean Fruit Fly

Adults are small, colourful flies with patterned wings, a habit typical of tephritid fruit flies. Larvae are pale, legless maggots found inside infested fruit. Because reliable species identification of tephritids can be difficult, suspected medfly finds are usually confirmed by specialists, often from trap catches.

Field signs include small egg-laying punctures in the fruit skin, softening and premature colouring or dropping of fruit, and maggots and breakdown inside cut fruit. These signs, plus trap captures, are the basis for detection.

Females insert eggs under the skin of host fruit, and the hatching maggots tunnel and feed inside before leaving the fruit to pupate, usually in the soil. Development is faster in warm weather, allowing several generations per year and continuous activity where host fruit is available across seasons.

The very wide range of suitable hosts means that, in favourable climates, some fruit is often available to sustain populations through much of the year, which contributes to the pest’s persistence and spread.

Maggot feeding destroys the flesh of the fruit and provides entry for decay organisms, so infested fruit becomes unmarketable and often drops early. Beyond direct losses, the pest’s quarantine status can close markets to host fruit from infested areas, adding major economic costs through trade restrictions.

The host range is very broad and includes citrus such as orange, lemon, and grapefruit, stone fruit such as peach and apricot, and tropical and subtropical fruit such as mango, guava, and fig, among many others.

Networks of baited traps are the primary tool for detecting and monitoring adult flies, and are used intensively in surveillance around production areas and ports. Fruit sampling for eggs and maggots complements trapping. In regulated areas, trap catches trigger defined quarantine and response actions.

Medfly is managed most effectively through coordinated, area-wide programmes within integrated pest management, rather than by isolated treatment.

• Support area-wide trapping and surveillance and follow quarantine requirements
• Practise sanitation by removing and destroying fallen and infested fruit that breed flies
• Use targeted bait applications and male-annihilation techniques where authorized
• Employ the sterile-insect technique as part of coordinated suppression or eradication where applied
• Use post-harvest treatments and certification to meet market access requirements