Non-significant trends towards earlier or later arrival date of the Pied Wagtail (Motacilla alba L.) in N-W Croatia

Over the past century, average global temperature increased by an approximately of 0.6°C and it has been show that global warming has been affecting many biological systems. Recent climate change has influenced birds in many ways. The aim of this work is to present trends in the first arrival date and potential impact of mean monthly temperature on the spring migration of the Pied Wagtail (Motacilla alba) in long-term study in northwestern Croatia (Mokrice rural area). The study was conducted during 1980–2011. The Pied Wagtail is a small, semi-hole nesting, migratory, insectivorous passerine breeding in Europe and Asia (also breeds in Morocco and western Alaska). This study didn’t show that over the research period the Pied Wagtail returned to their breeding sites significantly earlier. This can be explained with the fact that local temperatures for February/March, did not increase significantly (P> 0.05). The change in Pied Wagtail arrivals was very little and advanced 1.47 days (non-significant) over the study period (1980–2011).