BLM REA CYR 2013 Swainson's Thrush Potential Habitat

Some of the CYR rasters intentionally do not align or have the same extent. These rasters were not snapped to a common raster per the authors' discretion. Please review selected rasters prior to use. These varying alignments are a result of the use of differing source data sets and all products derived from them. We recommend that users snap or align rasters as best suits their own projects. - Swainson’s thrush is a small aerial insectivore common throughout Alaska. It is a long-distant migrant that breeds in western to northern North America, and spends its winters from southern Mexico to northern Argentina. In the Yukon Territory, Swainson’s thrush inhabits willow shrub and various forest types. In the Alaska taiga, Swainson’s thrush typically inhabits forested areas more than shrub thickets. Swainson’s thrush breed in pairs between June, July, and early August, and arrive in Southeast Alaska by mid-May. Clutch sizes are typically 3–4 with incubation lasting approximately 10–14 days. Young are tended by both parents until they leave the nest approximately 10–14 days after hatching. Reproductive success is estimated at 18% to 50% of nests that rear at least one brood to independence and life spans of at least 10 years have been reported for adults. Swainson’s thrush has a varied diet including insects and other invertebrates, small fruits and seeds. It is typically insectivorous during breeding and spring migration, with some populations converting to a more frugivorous diet during autumn migration and winter. Prior to migration, Swainson’s thrush will deposit fat stores on their summer grounds and will replenish these fat stores during migration as well. While Swainson’s thrush are common throughout Alaska, populations are reported as declining across their range, particularly in Alaska and the Northeast.