ADULT RESTING AND LARVAL DEVELOPMENTAL SITES OF STABLE FLIES AND HOUSE-FLIES (DIPTERA, MUSCIDAE) ON DAIRIES IN ALBERTA

Adult resting sites and larval developmental sites were determined for the stable fly, Stomoxys calcitrans (L.), and house fly, Musca domest ica (L.), at three dairies in southern Alberta during the summers of 1 990 and 1991. Adult stable flies were present throughout each dairy bu t showed a tendency to rest outdoors on east- and south-facing surface s of barns and fences, as well as along feed aprons. House fly adults tended to rest indoors. Stable fly larvae were most abundant in manure mounds, general lots, and indoors and were also abundant in silage mo unds and spilled silage. Fences, feed aprons, and lagoons had fewer st able fly larvae. House fly larvae were most abundant in silage mounds, followed by indoors and general lots. Peaks of stable fly capture on resting sites occurred in late August and mid-September and were prece ded by increases in the number of stable fly larvae per sample in mid- August and early September. Peak house fly captures occurred in August and early September, and larval populations peaked in early to mid-Au gust. Residual pesticides for controlling adult stable flies should be applied early to mid-August and priority given to east- and south-fac ing surfaces and barns. Applications for house fly control should begi n in early July and can be made primarily indoors. Sanitation should b e applied before july, and attention should be paid to the manure moun ds, general lots, and indoors.