A weather surveillance radar view of Alaskan avian migration

摘要: Monitoring avian migration within subarctic regions of the globe poses logistical challenges. Populations in these often encounter most rapid effects changing climates, and seasonally productive areas are especially important supporting bird populations-emphasizing need for monitoring tools strategies. To this end, we leverage untapped potential weather surveillance radar data to quantify active through airspaces Alaska. We use over 400 000 NEXRAD scans from seven stations across state between 1995 2018 (86% samples derived 2013 2018) measure spring autumn intensity, phenology directionality. A large bow-shaped terrestrial migratory system spanning southern two-thirds was identified, with birds generally moving along a northwest-southeast diagonal axis east 150th meridian, northeast-southwest west meridian. Spring peak ranged 3 May 30 between, 18 August 12 September during autumn, timing predicted by longitude, rather than latitude. Across all stations, intensity greatest as compared spring, highlighting opportunity seasonal indices net breeding productivity additional years measurements amassed.