Effect of airflow on house fly (Diptera : Muscidae) distribution in poultry houses

Numbers of fecal and vomit spots deposited by house flies, Musca domestica L., on spot cards were about twice as high on cards placed on the downwind sides as on the upwind sides of building support posts in caged-layer poult ry houses with tunnel ventilation in Brocksville, FL. This trend was strong er at the ends of the houses where airflow is faster than in the relatively still-air center of the houses. A similar evaluation conducted in a puller house (Zephyrhills, FL) with an evaporative cooling ventilation system rev ealed significantly higher ny counts on spot cards and sticky cards in down wind compared with upwind orientations. Flies in the puller house were conc entrated in both ends of the house and in the center, with comparatively fe wer flies in the intermediate regions. There was a high degree of correlati on between spot card and sticky card counts in the pullet house.