Survey of winter bird communities and vegetation in the Oregon Coast Range
Data files
Aug 03, 2022 version files 2.60 MB
Nov 07, 2022 version files 2.68 MB
Dec 08, 2022 version files 2.70 MB
Abstract
We re-surveyed forest bird communities during winter in seven large plots originally surveyed by graduate student, Stanley Anderson, from 1968 through 1970, near Corvallis, Oregon, USA. The forests in plots in the Coast Range Mountain foothills were and are currently dominated by Douglas-fir (Pseudotsuga menziesii). Anderson's thesis included plot locations, summaries of vegetation characteristics and point estimates of bird densities for each plot. Because of the lack of similar data, we re-surveyed his plots after aligning methods with his and added modern components (distance and time interval sampling) to facilitate comparisons of changes in abundances. We preserved more extensive metadata than were preserved from Anderson's surveys, including georeferenced point count survey locations to facilitate more precisely repeatable future re-surveys. We also measured vegetation characteristics to compare structural changes since Anderson's measurements.
Methods
Data were collected with 10 minute stationary counts conducted during winter from 2019-2022. Counts included either two five-minute intervals or ten 1-minute intervals where each bird was noted as detected or not detected. Distances to birds were also estimated. Two observers counted each plot in each year, with minor exceptions. Vegetation was measured within circular plots following methods of James and Shugart (1970; Audubon Field Notes). Details in README files for bird surveys and vegetation surveys. The raw data are archived herein.
Usage notes
README files saved as .txt and Spreadsheets saved as .csv.