Field Notes and Early Findings
In 2018, Klamath Bird Observatory began in-depth monitoring of the survival, nest success, and habitat preferences of Rogue Basin birds located near Lily Glen, east of Ashland, Oregon. This research is being replicated by partners in the Willamette Valley in Oregon, and the Puget Lowlands in Washington to get a picture of Oregon Vesper Sparrow population health across its entire range.
Over the last several years, KBO field crews have spent their spring mornings diligently watching Vesper Sparrows go about their business. The birds typically arrive from their wintering grounds in mid to late April and begin to settle in for the summer breeding season. We have witnessed the males defending their territories and attracting mates, watched as they paired up and the females began nest building, and observed them incubating their eggs and raising their young (for an intern’s account of his experience nest-searching, read his blog on the KBO Call Note). Field crews have located over 130 nests so far! Preliminary findings suggest nest success is within the expected range for a ground-nesting bird and likely not a cause for concern, although late-season hail and snow in 2021 and 2023 caused the failure of many nests. Changes in spring weather patterns, such as later or more severe storms, may exacerbate threats to this species in high-elevation meadows.
Over 100 adult sparrows and 180 nestlings have been banded with unique combinations of colored leg bands so that we can identify each individual on sight. Resighting efforts have taken place annually at Lily Glen to keep track of how many of these banded birds survive and return to the area year after year. We also partnered with the Vesper Meadow Education Program to implement a community science program in which volunteers searched for birds that had dispersed to the Vesper Meadow Restoration Preserve and other nearby meadows in and around the Cascade-Siskiyou National Monument. Early findings show low return rates for juveniles, which is not necessarily surprising because young birds are more likely to leave home and disperse to a different site for their first breeding season. After resighting efforts are completed in 2024, we will estimate the annual survivorship of adult males and females and fledglings if possible.
Through additional territory mapping studies at Vesper Meadow, we found that Oregon Vesper Sparrows nest on this property in relatively high densities, similar to those at our main study site. We expanded our research there in 2021 – 2024 with Motus radio telemetry technology and added GPS tagging to our activities at Lily Glen (see Expanding Research with Cutting-Edge Technology).
In 2024, KBO shifted gears to focus on a different aspect of fieldwork. We had the opportunity to explore our beautiful backyard Cascade-Siskiyou National Monument and search for meadows occupied by Oregon Vesper Sparrow. A previous inventory found several populations occupying sites in and around the Monument but was not comprehensive in surveying all potential suitable habitat. We identified and surveyed 54 mountain meadows comprising ~7400 acres of potential habitat. We observed at least one Vesper Sparrow at 27 of them, but only five sites had ≥10 individuals detected. We counted a total of 140 Vesper Sparrows within the Monument boundary, many more than the 2013 survey because we were able to cover much more ground. Understanding the population size and distribution of Vesper Sparrow in the Monument is critically important to land managers charged with maintaining biodiversity on public lands, especially if the subspecies is federally listed (currently under USFWS review).
This extensive research and community science effort in funded in part by the BLM National Conservation Lands Management Studies Support Program, Carpenter Foundation, Charlotte Martin Foundation, Oregon Conservation and Recreation Fund, Oregon Wildlife Foundation, Oregon Zoo’s Future for Wildlife Fund, Friends of the Cascade-Siskiyou National Monument, and U.S. Fish and Wildlife Service..
