US Fish & Wildlife Service
Date of this Version
2004
Citation
NORTHWESTERN NATURALIST 85:95–103 WINTER 2004
Abstract
The Tongass National Forest encompasses a large expanse of temperate rainforest in southeastern Alaska and contains 12 designated Research Natural Areas (RNAs). Existing in as near a natural condition as possible, RNAs receive minimal commercial and recreational use. Because few bird studies have been conducted on RNAs, we used point counts and area searches to determine the occurrence and abundance of breeding landbirds present in vegetation communities of RNAs. Of 49 species of small landbirds detected during area searches, the most widely distributed birds among RNAs were rufous hummingbird (Selasphorus rufa), chestnutbacked chickadee (Poecile rufescens), winter wren (Troglodytes troglodytes), golden-crowned kinglet (Regulus satrapa), Swainson’s thrush (Catharus ustulatus), hermit thrush (C. guttatus), varied thrush (Ixoreus naevius), and Townsend’s warbler (Dendroica townsendi). The 8 most abundant species recorded on 187 point counts (.0.5 birds/point) were Pacific-slope flycatcher (Empidonax difficilis), hermit thrush, varied thrush, winter wren, golden-crowned kinglet, Townsend’s warbler, and chestnut-backed chickadee. Several species had significant differences in abundance between low- elevation hemlock-spruce forest and their abundance in either high- elevation fir-spruce forest or mixed conifer-shore pine muskeg. Because RNAs provide forests that are not disturbed by human activities, these sites could provide a standard to evaluate changes in bird abundance and richness that may occur on developed land in southeastern Alaska.
Comments
U.S. Government Work