Loons breed across North America from the high arctic south to about 43 north latitude. (AOU 1983). Populations, particularly of Common Loons (Gavia immer) have recently declined in the continental U.S. and southern Canada (Sutcliff 1979, Titus and VanDruff 1981, McIntyre 1988). As a result, state and private natural resource organizations began more intensive monitoring of loon populations (in McIntyre 1986, Strong 1988). These surveys, however, are restricted to areas accessible by road, although recently aircraft were used for more remote areas (Lee and Arbuckle 1988, Strong 1990).