Data represent relative abundance and species composition of boreal forest birds in 45 aspens dominated mixedwood forest stands in central Saskatchewan, Canada. Surveys were conducted during the dawn chorus (between 04:00 and 09:00 AM) in June of 2014 that were revisits to historic research sites surveyed in June of 1993–1997. Data from a total of 235 locations (mean = 5 per stand; range = 3–10) were surveyed in 2014 compared to 257 (mean = 5 per stand; range = 4–11) in the historic surveys. Data were collected using 10-minute-long unlimited distance point-counts where all birds seen or heard were counted; however, observers only counted birds that were estimated to be within the stand and were not previously recorded on adjacent point-count stations. Two visits were conducted to each survey location within a given year. The included data represents the maximum count for a species across the two-visit which were then summed across all survey locations within a forest stand. Data from the historic (1993-1996) surveys are included. Analyses of these data suggested significant changes in the abundance of eight out of ten species examined. Red-eyed Vireo (Vireo olivaceus), Ruby-crowned Kinglet (Regulus calendula), Ovenbird (Seiurus aurocapilla), Yellow-rumped Warbler (Setophaga coronata), and Chipping Sparrow (Spizella passerina) were all less abundant than during historic surveys, whereas Mourning Warbler (Geothlypis philadelphia), Magnolia Warbler (Setophaga magnolia), and White-throated Sparrow (Zonotrichia albicollis) were more abundant. Further details on the survey methods, data manipulation, analyses and results are detailed in Van Wilgenburg et al. 2017. Avian Conservation and Ecology 13(1):3.
https://doi.org/10.5751/ACE-01145-130103. Scripts and data used in the original analyses are included.
Supplemental Information
https://doi.org/10.5751/ACE-01145-130103