Use of nest boxes by Vaux's Swifts

The use of nest boxes by Vaux's Swifts (Chaetura vauxi) was investigated because of the loss of large-diameter hollow trees used for nesting in northwestern North America. Nest attempts and nest success were compared in nest boxes among three habitat types in northeastern Oregon. Air temperatures in the boxes were monitored to determine if boxes overheated and resulted in nestling mortality. Thirty of 103 nest boxes were used by nesting Vaux's Swifts for at least one year during 1999-2002. Of 51 nest attempts, 53% successfully fledged 1-6 young ((x) over bar = 3.5 nestlings). Over this 4-yr period, 47% of the nests were in late-seral stage grand fir (Abies grandis) stands, 31% were in harvested stands of grand fir, and 22% were in ponderosa pine (Pinus ponderosa) stands. It appeared that temperature did not affect nest success in boxes because there were no significant differences in maximum and minimum temperatures between successful and unsuccessful nest attempts. Nest boxes provided alternative nest sites for Vaux's Swifts in habitats traditionally used by this species as well as in habitats that currently lack natural nest sites.