The timing of spring migration in trans-Saharan migrants: a comparison between Ottenby, Sweden and Capri, Italy Vårflyttningens tidsmönster hos tropikflyttare: en jämförelse mellan Ottenby, Sverige och Capri, Italien

ORNIS SVECICA 16: 27–33, 2006AbstractIntroductionOver the past decades many organisms have ad-vanced the timing of spring events, most likely in response to recent climate change (e.g. Stenseth et al. 2002, Walther et al. 2002, Parmesan & Yohe 2003). For instance, recent empirical work has demonstrated changing phenology patterns in the flowering of plant species (Fitter & Fitter 2002), in the emergence from pupae in insects (Roy & Sparks 2000), and in earlier breeding by amphibians (Beebee 1995) and birds (Crick et al. 1997). Most ornithological studies demon-strating temporal trends towards earlier spring arrival or egg-laying dates have been carried out in the temperate region of Europe and North America (reviewed by Lehikoinen et al. 2004, Dunn 2004), whereas only a few publications