MSU Extension Integrated Pest Management

Spotted wing drosophila (SWD) is an important insect pest of berry crops, including blueberries, blackberries, raspberries, strawberries, and cherries. SWD is native to Asia and was first detected in the mainland United States in California in 2008. It has since spread throughout the U.S. and has become the most economically important insect pest of berries. Male SWD have dark spots on the outer margins of their wings. Female SWD have a saw-like ovipositor (organ for laying eggs) that they use to cut the skin of ripe or ripening fruit and deposit eggs inside the fruit (Figure 1). Larvae feed inside the berries and develop through three larval stages within the fruit,
causing the fruit to degrade (Figure 2). Larger larvae are visible to the naked eye, and if they are detected
in the fruit, distributors may reject the contaminated loads of fruit. SWD injury also increases the risk of damage by other pests and fungal infections.