Various species of Drosophila are known as vinegar or pomace flies.
Populations build up as the fruit harvest season progresses.
Oblong pupae occur wherever larvae are found and have a forked breathing tube at one end. Eggs are laid in damaged or exposed fleshy tissue and larvae feed on the berries. The primary damage by this pest, however, is the sour rot organisms that it vectors from bunch to bunch in the vineyard. Any practice that reduces bunch rot will decrease populations of vinegar flies. Good sanitation practices in storage or processing plants are helpful in reducing populations of this pest.