In 2018, Klamath Bird Observatory began in-depth monitoring of the survival, nest success, and habitat preferences of Rogue Basin birds located near Howard Prairie, 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 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 100 nests! 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 caused the failure of many nests. Changes in spring weather patterns may exacerbate threats to this species at high-elevation meadows.
94 adult sparrows and 144 nestlings have been banded with unique combinations of colored leg bands so that we can identify each individual. Resighting efforts have taken place annually to keep track of how many of these banded birds survive and return to the area year after year. KBO field crews have completed ongoing resighting efforts at the primary field site at Lily Glen. We also partnered with 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 lower return rates for juveniles, which is not 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 2023, we will estimate the annual survivorship of adult males and females and fledglings.
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 (see Expanding Research with Cutting-Edge Technology).
Next spring, KBO’s researchers will hit the ground running (or more accurately, patiently watching and listening!), looking for returning sparrows, and noting which individuals have survived another year’s round-trip migration. Stay tuned for more updates!
This extensive research and community science effort are funded in part by the BLM National Conservation Lands Management Studies Support Program, Carpenter Foundation, Charlotte Martin Foundation, Oregon Wildlife Foundation, Oregon Zoo’s Future for Wildlife Fund, and Friends of the Cascade-Siskiyou National Monument.