The species Rhagoletis mendax is commonly known as the blueberry maggot and is a common pest to blueberry orchards, including Eastern Canada, where it is one of the most significant insect affecting blueberry crop quality and yield. The seriousness of this pest results from the presence of maggots within harvested fruit. The maggot is not hazardous to health; however, its presence makes fresh, canned or frozen fruit unacceptable for the market.
The species R .mendax has four growth stages ranging from egg, maggot, pupa and adult fly. The eggs are white in colour and extremely small. The maggot is white as well and measures approximately 8 mm in length; it is pointed at one end and blunt on the opposite end. The maggot will enter the soil around August to form the pupae. The following year the adult blueberry maggot will emerge, with the appearance of a small brown fly with white markings; of which the female has four and the male has.
Infestations of blueberry maggot can be detected before reaching a damaging level; through the trapping of adult flies. Trapping consists of yellow sticky boards baited with ammonium acetate or hydrolyzed protein. A treatment threshold of approximately 3 adults per trap per week (or 5 adults per field per week) gives adequate time for chemical control, if the traps are in place before the first flies emerge. The Blueberry maggot will cause shriveled and dropped berries, reducing both yields and the quality of the harvestable material.