Correlates of Wing Morphology with Foraging Behaviour and Migration Distance in the Genus Phylloscopus

Are Iberian ChiffchaffsPhylloscopus (collybita) brehmiilong-distance migrants? An analysis of flight-related morphology

“…Only seven out of more than 1000 ringing recoveries could be assigned to local individuals, which were always recovered at the same site and hence gave no information on movements (see Introduction). Based on the established evidence for a correlation between flight-related morphology and migratory behaviour (Winkler & Leisler 1992, Marchetti et al 1995, Mönkkönen 1995, our results support the idea that Chiffchaffs breeding in the Iberian Peninsula (brehmii) migrate longer distances than individuals wintering in this area (collybita). After controlling for body size and allometry of feather dimensions, breeding Iberian Chiffchaffs had a shorter tail and more pointed wings than birds wintering in the same areas.…”

“…Migratory birds benefit from having longer and more pointed wings and shorter tails, as this increases speed and reduces energy consumption during long-distance flights (Winkler & Leisler 1992, Mönkkönen 1995, Norberg 1995. In the absence of costs of migration, shorter and rounded wings and longer tails are favoured because they improve manoeuvrability and hence predator avoidance and foraging efficiency (Marchetti et al 1995, Swaddle & Lockwood 1998. Consistent with these relationships, shortdistance migrants have shorter and more rounded wings than long-distance migrants (Winkler & Leisler 1992, Mönkkönen 1995; for an example with Phylloscopus warblers, see Marchetti et al 1995).…”

“…The shape of the wings and tails vary between species and populations in relation to their migratory behaviour, even though these behavioural differences may be small (Marchetti et al 1995. Migratory birds benefit from having longer and more pointed wings and shorter tails, as this increases speed and reduces energy consumption during long-distance flights (Winkler & Leisler 1992, Mönkkönen 1995, Norberg 1995.…”

Range expansion and the possibility of an emerging contact zone between two subspecies of Chiffchaff Phylloscopus collybita ssp.

“…Long-distance migrants have more pointed wings than short-distance migrants (Marchetti et al 1995, Mö nkkö nen 1995, probably because high wing pointedness results in a high aspect ratio which reduces the cost of transport by allowing faster and more energyefficient flight (Rayner 1988, Norberg 1989. We found wings to be significantly longer and more pointed in northern than southern male Chiffchaffs, suggesting that the former's wintering grounds are farther away from the breeding grounds.…”

Convergence of broad-scale migration strategies in terrestrial birds

“…The resulting selection pressures have generated a unique set of morphological, physiological, and behavioural adaptations [5][6][7], whose quality varies based on the rigors of the migratory journey. For example, individuals that migrate longer distances tend to have adaptations that improve the efficiency of migratory flight [8][9][10]. The presence of geographical barriers to migration is an additional factor that may affect the quality of these adaptations.…”