Oporornis agilis

Widespread in the breeding season, but there is evidence of ongoing declines. Possible threats not well understood. Forest conversion to agriculture is continuing along southern edge of boreal forest in western Canada.

BREEDING: east-central British Columbia across southern Canada to west-central Quebec, south to southern Manitoba, northern Minnesota, northern Wisconsin, central Michigan, and south-central Ontario. MIGRATION: Rare autumn transient through the eastern West Indies (and most notably on Bermuda) and through northern Venezuela and northeastern Colombia; western and central Venezuela, northern and eastern Colombia, western and central Amazonian Brazil, and southeastern Peru (Ridgely and Tudor 1989). WINTER: Winter range poorly known, since small population is spread over large area. Winters in northern South America, primarily east of the Andes around the Amazon basin (Pitocchelli et al. 1997). Noted rarely in spring as a transient through northern South America and Panama.

HABITAT LOSS/DEGRADATION: Few data, needs study (Pitocchelli et al. 1997). Much of the core of this species' range is in the western boreal forest, so is threatened by forest conversion to agriculture along the southern edges of the boreal zone. In Saskatchewan alone, 4368 square kilometers of forest was lost to agriculture in the period 1966-1994, a rate of -0.87%/year (Hobson et al. 2002). Much of the remaining southern boreal forest in western Canada has been leased to forestry companies (Cummings et al. 1994, Stelfox 1995). May be suffering from habitat loss on wintering grounds (Rappole 1995).

COLLISIONS: Many reports of migrants striking buildings, lighthouses, or towers (Pitocchelli et al. 1997); in Wisconsin, 300 birds were reported killed in this fashion in one season, 140 in one night in Eau Claire (Robbins 1991).