The bird surveyor team of Birds & Bloom, 2022
Methods
To evaluate the avian response to the 2018 Oregon white oak restoration project, the Birds & Blooms team followed Bob Altman’s 2018 breeding bird survey path and conducted a presence-absence area search, supplemented by a second area search within the woodland area (See Figure 1). Bob Altman, an ornithologist in the Pacific Northwest and current coordinator at the American Bird Conservancy, previously surveyed avian species in the oak prairie at Dorris Ranch, and this data was used as the baseline data for the bird specialist sub-team. Altman’s work, as well as some adjustments made by the bird specialist sub-team to increase identifications and detectability, helped lay the foundation for the Birds & Blooms bird survey protocols. The area search protocols along Altman’s path and the oak woodland path helped the Birds & Blooms team document habitat effects on avian diversity and abundance within Dorris Ranch, especially for the 20 special status species designated by the U.S. Fish and Wildlife Service and Oregon Department of Fish and Wildlife.
Area Search Protocol
The bird specialist sub-team followed Altman’s breeding bird survey path at a strolling pace for approximately 60 minutes to listen, look, and record data. To supplement the Altman path, we also walked a path through the oak woodland restoration area, following the same area search method for approximately 45 minutes. On both paths, the sub-team practiced an intuitive meander while assessing the presence or absence of our target bird species to support our assessment of avian response. These surveys were conducted throughout the breeding/migratory season, three times over the course of the term, with at least seven days in between each survey conducted. It was required that the surveys be conducted during favorable weather conditions and between sunrise and 9:30am to minimize time-of-day and conditional biases. For each three surveys the start time was staggered at 7:30am and 8:30am to avoid time-of-day bias. All species detected within the boundaries of our site were recorded, along with the number of individuals for each of our 8 special status species.
| Highly Oak Associated Target Bird Species and Special Status Species (in bold) | ||
| Acorn Woodpecker | Chipping Sparrow | Spotted Towhee |
| Black-capped Chickadee | Downy Woodpecker | White-breasted Nuthatch |
| Black-headed Grosbeak | Hutton’s Vireo | Willow Flycatcher |
| Bewick’s Wren | Lazuli Bunting | Western Bluebird |
| Bushtit | Lesser Goldfinch | Western Tanager |
| California (Western) Scrub-jay | Purple Finch | Western Wood-pewee |
| Cassin’s Vireo | Rufous Hummingbird | Yellow-breasted Chat |
Figure 1: Routes followed by bird specialists. Route #1: Bob Altman’s survey path (yellow), #2 oak woodland path (green)
