GPS has revolutionized the study of bird migration by revealing details of migration routes, timing, and connectivity not discoverable through other methods. To date studies tracking migrations of raptors using GPS have been restricted to species whose size, behavior, and habitat permit the use of solar-rechargeable GPS transmitters. We tested the use of battery-powered GPS transmitters programmed on highly conservative fix schedules to track migrations of Long-eared Owls (Asio otus), a medium-sized forest owl. Long-eared Owls (n = 5) were fitted with GPS transmitters on their wintering grounds in New Jersey and tracked over the subsequent months. Mortality among the GPS-tagged owls was high, consistent with previous reports in related species. Surviving owls (n = 2) migrated north beyond currently recognized eastern North American range limits, spending summers at 50–55°N in spruce-moss and spruce-lichen (taiga) forests in a vast undeveloped region of northern Quebec. This pilot study demonstrates that lightweight, battery-powered GPS transmitters programmed on highly conservative fix schedules can reveal long-distance movements in medium-sized (e.g., <300 g) birds. This approach may help addresses data deficiencies for birds whose habitat and behavior would cause solar transmitters to perform poorly, particularly species for which details of large-scale movements are lacking.

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