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Pests > Pest Management > Quarantine > Sampling & surveillance > Fruit fly surveys, surveillance, Samoa

Pests Pest Management Quarantine Sampling & surveillance Fruit fly surveys, surveillance, Samoa

Fruit fly surveys, surveillance, Samoa

November 2013. Samoa is trying to improve its trapping and host fruit collection as part of its quarantine surveillance program. It is targeting ports of entry and tourist areas, hotels, beaches and national dumps. It is targeting the hosts of two fruit flies, Bactrocera xanthodes and B. kirki. what other areas should be included?

Members added other sites:

national parks
public and domestic gardens
wild fruit plants (forests)
fruit industry (nurseries and orchards)
compost preparation area
yatchts (and yatcht clubs) and cruise ships
checks should be made of amnesty bins to check relative risk of countries
post-entry quarantine/incinerator areas

BUT members thought that tourists are not the likely people to be carrying fruit (especially fruit outside the commercial pathway): it’s locals returning home from holiday, visiting relatives, students, etc. Tourists come to taste local fruit not foreign fruit so hotels should be a low priority and villages and local residential areas the highest priority.

In support of this, the following paper from Papua New Guinea was provided:

Putulan, D, S Sar, RAI Drew, S Raghu and A R Clarke (2004) Fruit and vegetable movement on domestic flights in Papua New Guinea and the risk of spreading pest fruit-flies (Diptera: Tephritidae). International Journal of Pest Management 50(1): 17-22.

Abstract: Species of tropical fruit-flies (Diptera: Tephritidae: Dacinae) are the foremost horticultural pest in the Pacific region. In Papua New Guinea (PNG), limiting the movement of fresh fruits and vegetables (=fresh commodities) between different regions within the country is one plant protection strategy that could lessen the threat posed by fruit-flies by restricting the spread of both exotic and indigenous pest species. In order to assess the risk posed by informal fruit and vegetable movement, we carried out a survey of Papua New Guinea domestic airline passengers. Of 1904 passengers surveyed, 38.9% were carrying fresh commodities. Over 70 different fresh commodities were being carried, the most common being bananas and peanuts, each being carried by >9% of passengers. Thirty-four of these 70 commodities are known fruit-fly hosts from PNG or other countries. Sixty-three percent of passengers on flights into the National Capital District (i.e. Port Moresby) were carrying fruit, as were 74% of passengers leaving the Highland Provinces. Neither the purpose of travel nor the occupation type of a passenger influenced the likelihood of commodity carriage. Nearly all commodities came from gardens or local markets and were being carried predominantly for personal consumption or gifts. With fruit-fly infestation rates of susceptible crops being around 20%, we conclude that the risk of transport of fruit-flies is very high.

For host fruit surveys, remember to collect as many varieties/species as possible; do not restrict the collections to common fruits only, but include non-commercial types, native and inedible ones too.

Additionally, when placing the traps, keep in mind the distance of attractiveness of the two common lures – CUE: approx. 300 m; and ME: approx. 500 m – for efficient use of resources.

Later, a member in St Helena asked about trap designs and baits for the fruit flies present there: B. cucumis, B. cuurbitae, B. dorsalis, Ceratis cosyra, C. rosa and C. capitata. In response, another member suggested looking at the FAO fruit fly trapping guideline:

The Fruit Flies Surveillance Program in Mozambique(see link below) also looks at the species of fruit flies you’re interested in. There is a table in that document that should help with the attractants. They should be mixed with an insecticide (see FAO guidelines for more details). In Samoa in the early 1990s Steiner traps were used, and later in Mozambique, Lynfield traps.