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Vincent S. Cavalieri

Publications and source records attributed to Vincent S. Cavalieri.

2 recordsLinked to original sources

Cerulean Warbler occurrence and habitat use in Oklahoma

Dendroica cerulea (Cerulean Warbler) is a migrant songbird that has declined rangewide in recent decades. We surveyed 150 sites in 2006–2007 to determine if this species still occupied its former breeding range in Oklahoma. We located Cerulean Warblers at 5 sites and confirmed breeding on north slopes of two heavily forested ridges in the Ouachita Mountains. We did not encounter Cerulean Warblers in any bottomland hardwoods, despite the former widespread distribution and abundance of the species in such habitats. While habitat loss and degradation may limit occurrence of Cerulean Warbler in some areas, the pattern of decline for this species at the edge of its range in Oklahoma is also consistent with abandonment of peripheral range as the range-wide population declines.

Oklahoma

A bird community on the edge: habitat use of forest songbirds In eastern Oklahoma

Several species of forest songbirds reach a western limit of their respective distributions in eastern Oklahoma. The relative infl uence of various habitat variables on patterns of occurrence in this region may differ from those same infl uences in the core of species’ ranges. We examined the infl uence of 16 habitat variables on the occurrence and density of a suite of forest songbirds. We sampled breeding birds with four, fi xed-radius point counts along 1-km transects at 75 forested sites in eastern Oklahoma in 2006. Forest cover at fi ne scales varied by numerous structural characteristics (e.g., canopy cover) as well as species composition (e.g., pines vs. hardwoods). We performed both Detrended Correspondence Analysis (DCA) and Canonical Correspondence Analysis (CCA) ordinations using 16 environmental variables and 37 bird species to examine bird habitat relationships. Forward Selection in CCA indicated that the most important environmental variables affecting bird habitat relationships were the amount of forest cover in the surrounding landscape matrix, and at a local scale, canopy height and elevation.

Oklahoma