Aims: Contributing to know the migration strategies of goldfinches Carduelis carduelis passing over through the western edge of Pyrenees, focusing in time-associated variations in age and sex ratios and morphology.
Location: Txingudi and the surrounding mountain ranges, in NE Guipúzcoa (N Iberia).
Methods: Systematic sampling (ringing) sessions between Oct and Apr, from Mar 2004 to Apr 2008.
Results and discussion: Both sex and age ratios were similar among periods (autumn and spring migrations, and winter), with the same proportion of sexes and an age ratio biased to juveniles (80 % of captures). Concerning biometrics, spring migrants showed a shorter wing and tail, and were more fuel loaded than birds from autumn and winter. During autumn, adults tended to pass later than juveniles, as did long-distance like migrants (presumably from more northern breeding quarters) in relation to shortdistance like ones. Both sex and age ratios did not vary across the spring, and long-distance like migrants tended to pass over earlier than short-distance like ones.
We use own and third party cookies for the proper operation of the Website, carrying out analytical metrics, showing multimedia content and advertising, and interacting with social networks. More information in our Cookies Policy.