American Woodcock and Golden-winged Warbler Abundance and Associated Vegetation in Managed Habitats

作者:Bakermans Marja H; Ziegler Cassandra L; Larkin Jeffery L
来源:Northeastern Naturalist, 2015, 22(4): 690-703.
DOI:10.1656/045.022.0405

摘要

Vermivora chrysoptera (Golden-winged Warbler) and Scolopax minor (American Woodcock, hereafter, Woodcock) are 2 young-forest-dependent species of eastern North America that are experiencing population declines due to loss of breeding habitat. The goals of our study were to compare avian abundance and habitat similarities and differences in sites used by the 2 species. A portion of our survey plots were manipulated under Woodcock or Golden-winged Warbler habitat prescriptions in managed shrublands, and others were on regenerating timber-harvest sites. In north-central PA, we compared Woodcock abundance in 10-ha experimental plots assigned to one of 3 habitat prescriptions: uncut controls, Woodcock strip plots, and Golden-winged Warbler mosaic plots. We also quantified vegetation characteristics in each 10-ha study plot. Woodcock density was higher in the strip (4.8 males/10 ha) and mosaic (5.1 males/10 ha) plots compared to the uncut reference plots (3.3 males/10 ha). Woodcock density was negatively correlated with sapling cover in the north-central PA study plots. In regenerating timber harvests in northeastern PA, we demonstrated that vegetation characteristics overlap regardless of whether we detected only Woodcock or both species. Mean basal area of harvested stands with only Woodcock (i.e., 11.5 m(2)/ha) was greater than the mean basal area in stands used by Golden-winged Warbler (8.4 m(2)/ha). Our results suggest that creation of young forests at the stand level using either the Woodcock or Golden-winged Warbler habitat guidelines has benefits for both species. However, the Golden-winged Warbler is less flexible in the density of herbaceous cover and residual trees it requires. We recommend that in areas where the 2 species coexist, the Golden-winged Warbler guidelines be implemented to benefit both species.

  • 出版日期2015-12