Using Motus Technology to Inform Conservation of the Oregon Vesper Sparrow
Fall 2020 saw the installation of the very first Motus station in Oregon at the Vesper Meadow Restoration Preserve in partnership with the Vesper Meadow Education Program. The Motus Wildlife Tracking System is a collaborative research network using automated radio telemetry stations to study the movements of small organisms. Tags are small enough to be carried by birds, bats, and even bees. Motus tags emit a radio frequency that can be detected by a nearby Motus station anywhere in the world, and the number of stations is quickly growing.
We are using Motus technology to enhance our ability to track movements of the at-risk Oregon Vesper Sparrow. In 2021, we searched for nests of this ground-dwelling bird at Vesper Meadow, and placed Motus- compatible LifeTags on 12 Oregon Vesper Sparrow nestlings that were nearly ready to fledge. LifeTags are solar-powered and emit a signal every few minutes during daylight hours for the lifetime of the bird. The automated “resighting” and location estimation from this new technology will help us study habitat use, movements, and survival of young birds during the post‐fledging period when they are particularly vulnerable, and explore dispersal of birds returning to nearby meadows next spring. We also set up an array of 18 Motus nodes around the edge of Vesper Meadow to supplement our main Motus station there. Four of the nodes formed a mini-grid around two of the nests with tagged nestlings, and this will serve to pilot the use of this technology to track precise fledgling locations and habitat use. We collected tens of thousands of detections of our tagged fledglings from the node network over the months of June-October – and likely a lot of radio frequency “noise” from other stray signals – and we look forward to sorting through and analyzing those data this winter.
The Oregon Vesper Sparrow is a subspecies of conservation concern, and it has been petitioned for listing under the Endangered Species Act due to its low population size and declining trend. We have noted low rates of fledged young returning to our field sites at Lily Glen and Vesper Meadow for their first spring as breeding adults. Motus technology will help us determine the cause – are young birds having trouble surviving the vulnerable post-fledging stage, or their risky first round-trip migration and winter? Or are they simply moving away from the meadows where they were born and choosing other nearby meadows to try raising their own young? A handheld radio telemetry antenna will allow us to more easily locate any tagged birds that disperse away from our main field sites to other nearby meadows next spring.
In addition to enhancing our Vesper Sparrow research, the Motus station at Vesper Meadow has detected two Lewis’s Woodpeckers migrating from MPG Ranch lands in Montana, one Swainson’s Thrush that was banded in interior British Columbia, and a Western Sandpiper and Semipalmated Plover from coastal British Columbia – so the station is assisting other researchers with their migration tracking projects as well! Our Motus station, node network, and tagging effort were made possible by the USFWS, MPG Ranch, Oregon Wildlife Foundation, and private donations.
Click here to learn more about our work with the Oregon Vesper Sparrow.
