It has been recorded in both wet and dry areas, from sea level to heights of more than 13,000 feet. They have sometimes been spotted hunting at night in the glow of streetlights, especially in country parks, but during the day they carefully hide themselves. Mothers with young roost in foliage along forest edges or in fencerows, generally 12 to 40 feet above ground. In a study in Iowa, these bats were most often found in fencerows between crops, protected by dense vegetation above with unobstructed space below. These features undoubtedly aid them in escaping from a variety of birds and other predators.
Hoary bats live alone except during fall migration and when mothers are accompanied by their young.
Although both sexes sometimes spend summers in the same general regions, males are normally scarce in areas where mothers raise their pups. In North America, these areas are primarily in the midwestern United States and north into Manitoba, Canada. A few rear young in eastern forests as far south as Arkansas, Louisiana, and Tennessee. Females prefer low elevations, while males are more often found in mountainous areas, particularly from West Texas through Arizona, and northward through at least Oregon. At BCI's workshops in the mountains of southeastern Arizona, we net more than a hundred hoary bats each summer.