Attraction of walking Tribolium castaneum adults to traps

The red flour beetle, Tribolium castaneum (Herbst), is a major pest of food processing facilities and can be monitored using pitfall type traps. To determine how beetles interact with these traps under field situations, the behavior of individual beetles released in the vicinity of traps was observed in a large arena. Specifically, the response of adults to traps baited with combinations of commercially available pheromone and kairomone attractants was measured, as was the influence of beetle sex and strain, airflow presence or absence, and distance from trap. The beetle's response to traps was strongest (e.g., more encountered trap, more remained in observation zone, more time was spent on treatment side, and decreased speed and increased turn angle) to pheromone/kairomone or pheromone baited traps when there was air movement, while kairomone alone and all attractants under still air conditions generated no significant response by the beetles. Even with the best combination of attractants and with airflow, average number encountering trap was only 40%. With airflow, beetles were successful at locating a pheromone/kairomone baited trap out to 90 cm, the maximum distance tested, but under still air conditions even at 10 cm there was no difference between traps with and without attractants. Since airflow at trap locations within commercial food facilities can vary considerably, these patterns of response to traps could significantly impact insect detection. Published by Elsevier Ltd.