Use of artificially created Douglas-fir snags by cavity-nesting birds

C. L. Chambers; T. Carrigan; T.E. Sabin; J. C. Tappeiner; W.C. McComb

doi:10.1093/wjaf/12.3.93

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Use of artificially created Douglas-fir snags by cavity-nesting birds

C. L. Chambers·T. Carrigan·T.E. Sabin·J. C. Tappeiner·W.C. McComb

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Abstract

In western Oregon, we created snags by sawing tops off live Douglas-fir ( Pseudotsuga menziesii ) (n = 821) trees and monitored their condition and use by cavity-nesting birds. We created snags in three silvicultural treatments: modified clearcut stands, two-story stands, and small-patch group-selection stands. We used two snag patterns: clumped and scattered. Created snags averaged 3.8/ha in density, 17 m in height, and 75 cm in diameter. Chainsaw-topped snags were used by cavity nesters within 5 yr of creation. Abundance of excavated cavities increased in all silvicultural treatments (P = 0.0001) and was higher in two-story and clearcut stands than in small-patch stands (P ≤ 0.0004). We did not, however, find that snag pattern (clumped v. scattered) affected use by cavity-nesting birds based on abundance of excavated cavities (P > 0.6). We observed excavated cavities in five hardwood species indicating that hardwoods represented an important resource for cavity-nesting birds. Creating conifer snags by topping and retaining hardwoods may retain or increase populations of cavity nesters in areas with low natural snag density.

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Western Journal of Applied Forestry Article

Source-reported bounding extent: 42.03188415766749° to 46.24864258712557° latitude; -124.75465522303935° to -121.04270845604889° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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C. L. Chambers, T. Carrigan, T.E. Sabin, J. C. Tappeiner, W.C. McComb. 1997. Use of artificially created Douglas-fir snags by cavity-nesting birds. https://doi.org/10.1093/wjaf%2F12.3.93

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