Use of hollow trees as diurnal resting shelter byLutzomyia shannoniDyar was studied on Ossabaw Island, Chatham County, GA. This species was collected in large numbers from constrictive openings (tree holes) leading into living hardwood trees that contained larger internal hollows. Laurel oak (Quercus laurifoliaMichaux) and live oak (Q. virginianaMiller) were the most commonly used species. Regression analysis demonstrated no significant correlation between mean number of sand flies trapped from individual tree holes and six environmental variables: tree species, crown class, and diameter of the trees containing the holes; and area, compass bearing, and height above ground of tree holes from which flies were collected. The mean number of sand flies captured from individual hollow trees in 1990 was similar to and significantly correlated with the mean number of sand flies collected from the same trees in 1988, indicating that the tree-hole niche is stable for sand flies over time at this site.