Key migration numbers and 3-day mean location data of Common, Pallid and Alpine Swifts

We captured Common, Pallid and Alpine Swifts from breeding colonies at three different locations in Israel (Ramat-Gan, Mount Sodom and Haifa) during the breeding season in the years 2017 to 2020. Using a full-body harness, we attached 29 multisensory light-level geolocation (ms-GLS) loggers on Common Swift, 20 ms-GLS loggers on Pallid Swifts and 10 ms-GLS loggers on Alpine Swifts. Additionally, we equipped another 10 Pallid Swifts with light-level geolocation loggers that had the ability to remotely download the data by radio (rd-GLS). Of these, we recovered data from 35% (10/29) of the ms-GLS loggers on Common Swifts, 25% (5/20) on Pallid Swifts, and 80% (8/10) on Alpine Swifts. For the rd-GLS loggers, we successfully downloaded data from 70% (7/10) of the Pallid Swifts. We were able to use data over the full annual cycle from 10 loggers for Common Swifts, 10 for Pallid Swifts and five for Alpine Swifts. Additionally, we had data only until the arrival at the non-breeding range for one Alpine Swift and two Pallid Swifts. One of the Pallid Swifts (20MX) provided data over two annual cycles, of which we only used the first year in the analysis. In addition to attaching the GLS on the swifts, we measured their wing length and weight, and collected feather samples for molecular sexing (Griffiths et al., 1998) that was done by the Karnieli Vet Ltd. laboratory.