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The development of increasingly small devices for the satellite tracking of small birds allows us to explore aspects of avian migration that have never been studied before. Here, we provide the results of using 12- and 9.5-g platform transmitter terminals (PTTs) to track game birds of 300–385 g. Attaching PTTs to 20 Woodcocks (Scolopax rusticola), wintering in Spain from 2006 to 2012, allowed us to explore (1) migration strategies (timing, velocity and stopovers), (2) the identity of the breeding grounds; (3) inter-year site fidelity to wintering grounds. We provide details of the route, speed and timing of migration and the location of remote breeding sites that were unknown prior to this study. The departure from winter quarters (median date) was completed by 20 March. The spring migration period lasted 40 days, and our birds were found to travel from >5,000 to >10,000 km, with a mean total migratory speed (i.e., including stopovers) of 170 km/day. Woodcocks followed fairly direct routes of migration. Stopover duration tended to be shortened when birds were closer to their breeding areas, which were located further east than previously stated. The only bird that provided long-term data (>1 year) was observed to return to the same wintering area, suggesting high winter site fidelity. The use of small PTTs opens new research lines related to the study and management of small to medium-sized migratory birds.

Success of migration in birds in part depends on habitat selection. Overall, it is still poorly known whether there is habitat selection amongst landbird migrants moving across landscapes. Europe is chiefly covered by agro-forestry mosaic landscapes, so migratory species associated to either agricultural landscapes or woodland habitats should theoretically find suitable stopover sites along migration. During migration from wintering to breeding quarters, woodcocks (Scolopax rusticola) tagged with PTT satellite-tracking transmitters were used to test for the hypothesis that migrants associated to agro-forest habitats have no habitat selection during migration, at a meso-scale level. Using a GIS platform we extracted at a meso-scale range habitat cover at stopover localities. Results obtained from comparisons of soil covers between points randomly selected and true stopover localities sites revealed, as expected, the species may not select for particular habitats at a meso-scale range, because the habitat (or habitats) required by the species can be found virtually everywhere on their migration route. However, those birds stopping over in places richer in cropland or mosaic habitats including both cropland and forest and with proportionally less closed forest stayed for longer than in areas with lower surfaces of cropland and mosaic and more closed forest. This suggests that areas rich in cropland or mosaic habitat were optimal.