Cliff Swallow

On 1 July 2019, Erika and I were surprised to discover Cliff Swallows nesting under the eaves of a covered, wooden picnic kiosk along a boardwalk in the Nisqually National Wildlife Refuge. We usually find Cliff Swallows nesting under bridges. Turns out that these swallows used to be birds of the Rocky Mountains, where they nested under rock ledges. Only during the past century have these swallows moved east, through the Great Plains and into the East. At this time, land was being cleared and highway culverts, bridges and buildings were being constructed. Even today, Cliff Swallows are moving into new areas (Brown et al. 2017). These authors also write that now Cliff Swallow numbers are declining in the Northeast due to competition from House Sparrows that take over the swallow nests.