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Knowledge of spatio-temporal animal distribution patterns is one of the main chapters of wildlife research, not only due to its biological and ecological importance but also its usefulness in the conservation and management of animal populations. Iberia is a target wintering region for the Eurasian woodcock (Scolopax rusticola). The aim of the present work is to determine which factors shape woodcock distribution patterns during the winter period. To ascertain this, we used data collected over three consecutive years (winter of 2010/2011–2012/2013) in a region from northern Iberia (Gipuzkoa). Woodcock numbers (W) were modeled using generalized linear mixed models. The models that best fitted our data included a significant effect of latitude, land uses, sampling year, and type of meadow on W (once weighted for the number of visits and the area of each meadow). Overall, W tended to be lower in sites from southern Gipuzkoa, in those areas where there was a higher proportion of tree plantations, in grazed mountain pastures, and during the winters of 2011 and 2012 in relation to 2010 (mean ± SD values in 2010, 0.4 ± 0.5 woodcocks/ha; 2011, 0.2 ± 0.3 woodcocks/ha; 2012, 0.2 ± 0.4 woodcocks/ha). Part of the observed variance was due to the “year” effect, which could include several potential explanatory variables. Future research should try to add variables such as year-associated meteorological conditions, at both breeding and non-breeding quarters. Locally, a mosaic of some forest/woodland with abundant meadows would allow numbers of woodcocks to reach an optimum within the region. Moreover, the species was more abundant in the north; hence, the zones close to the coast had more importance from a conservation standpoint.

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.

Seasonal fluctuations in marine prey availability aroundbreedingcoloniesareoneofthemajorfactorsaffecting resident behaviour in seabirds. This is particularly applicable to large gulls (Larus spp.). The effect of refuse management on large gulls has been studied chiefly in relation to breeding dynamics, but it is less understood with regard to movement patterns. Our aim was to test whether the closure of one large dump andtheuse offalconryto detergull access to two others, within the southeastern Bay of Biscay area, affected the forag- ing distance of local yellow-legged gulls (Larus michahellis). During a period of seven consecutive winters between 2005 and 2011, the proportion of gulls that moved less than 50 km from their natal site was 70 %. However, during the winter of 2010, when they were deterred from accessing refuse tips within the region, gulls were found to travel longer distances. This result was explained neither by a decreasing survey effort near colonies nor by a decrease in apparent availability of marine prey, thus supporting the hypothesis that refuse man- agement within the region influenced the movement patterns of local gulls.