Date Time Invasive Flies Prefer Untouched Territory When Laying Eggs A recent study finds that the invasive spotted wing drosophila (Drosophila suzukii) prefers to lay its eggs in places that no other spotted wing flies have visited. The finding raises questions about how the flies can tell whether a piece of fruit is virgin territory – and what that might mean for pest control. D. suzukii is a fruit fly that is native to east Asia, but has spread rapidly across North America, South America, Africa and Europe over the past 10-15 years. The pest species prefers to lay its eggs in ripe fruit, which poses problems for fruit growers, since consumers don’t want to buy infested fruit.