Data from: A circannual perspective on daily and total flight distances in a long-distance migratory raptor, the Montagu's harrier, Circus pygargus

Long-distance migrants are particularly recognized for the distances covered on migration, yet little is known about the distances they cover during the rest of the year. GPS-tracks of 29 Montagu's harriers from breeding areas in France, The Netherlands and Denmark showed that harriers fly between 35 653 and 88 049 km yr−1, of which on average only 28.5% is on migration. Mean daily distances during migration were 296 km d−1 in autumn and 252 km d−1 in spring. Surprisingly, males' daily distances during breeding (217 km d−1) were close to those during migration, whereas breeding females moved significantly less (101 km d−1) than males. In terms of flight distance, the breeding season seemed nearly as demanding as migration periods for males. During the six winter months, both sexes moved less (114 and 128 km d−1 for females and males, respectively) than during migration. Harriers therefore covered shorter daily distances during winter which might allow birds to compensate for the more demanding phases of migration and breeding.

The data package contains two datasets:
- Schlaich_etal_2017_BiolLetters_gps_tracking_data_20170410
This file contains the GPS-tracking data of Montagu’s Harriers used for analyses on daily and total flight distances and contains the following columns: season (name of the bird, years), population (France, Netherlands, Denmark), sex, date_time (date and time in UTC), ann.rough (annotation of annual cycle phases: breeding, autumn migration, winter, spring migration), latitude, longitude, speed_2d (instantaneous speed measured by the GPS-device).

- Schlaich_etal_2017_BiolLetters_ high_resolution_data_20170410
This file contains the high resolution GPS-tracking data of Montagu’s Harriers used to calculate correction factors according to sampling interval and contains the following columns: season (name of the bird, years), date_time (date and time in UTC), ann.rough (annotation of annual cycle phases: breeding, autumn migration, winter, spring migration), latitude, longitude, speed_2d (instantaneous speed measured by the GPS-device).