Energetics and decision making of migration or residency

The energetics and decision-making process underlying whether to migrate or not are still largely unexplored. What are the energetic benefits of migrating to milder wintering areas versus staying at the breeding sites? We investigate these questions with the partially migratory Common blackbird. Using radio telemetry and implantable heart rate and body temperature data loggers we quantify the energetic costs of different wintering strategies in free-living individuals with an unprecedented high resolution.