Effect of trap color, bait, shape, and orientation in attraction of blueberry maggot (Diptera: Tephritidae) flies

Yellow, green, red, and blue sphere traps (9 cm diameter) were equal to or better than Pherocon AM yellow board traps in attracting blueberry maggot, Rhagoletis mendax Curran, flies. Because the sticky surface area of the Pherocon AM yellow board trap is 1.6 times greater than the sphere, sphere traps captured more flies per unit area. Both sphere and yellow board traps baited with ammonia were significantly more attractive than unbaited traps, thus ammonia may be the primary cue in attraction over trap shape or color. Ammonium carbonate dissipated within 2 wk from polycon dispensers and improvements in dispensers mat allow season-long monitoring of blueberry maggot flies. More female than male flies were captured on ammonia baited traps over the season, which is consistent with findings that Rhagoletis female flies seek a protein source for egg maturation. A shift from yellow boards to spheres as the season progressed was not observed.