| Abstract |
The Woodchat shrike (Lanius senator), is a migratory long distance passerine, which crosses the Sahara Desert and the Mediterranean sea, returning from the wintering to the breeding areas. During its trip, one of the stopover sites is Antikythera.
Based on our data (2007-2011), the median arrival date for the species in Antikythera is the 24th of April. Males were found to arrive earlier (22th of April) compared with females (26th of April). This finding enhances the theory that early arrival at the breeding areas may increase the reproductive success of males.
The adults were found to arrive earlier in Antikythera (20th of April), compared with juveniles (27th of April). This is based on the fact that juveniles lack experience, which may affect the time of arrival and the research for territories.
Investigating the correlation between the median arrival date of the migration, for all the individuals and for the all the years for which we collected data, we found that there is a tendency for birds to return earlier from Africa.
About the appearance of a specific pattern concerning the passage of the individuals from the island, no correlation was found between the median arrival date on the island and the morphometric characteristics of the species. From our data, it appears that there is an increase in the body mass of Woodchats with increasing latitude. Specifically, it seems that Woodchat shrike begins to refuel in North Africa.
From the mean body mass and the mean fat tissue of individuals who arrive on Antikythera, individuals do not seem to get under great harassment because of their migratory flight.
The direction followed by the Woodchat shrike during spring migration is north, slightly east and it is capable to reach up to Bulgaria.
The habitat of Woodchat shrike during the spring migration period, consists of open, dry grasslands with isolated trees and shrubs used as places of research and hunting. Individuals roost in the bushes and trees, of which each bird explores the territory, searching for prey on the ground. The Woodchats seems to prefer open areas with low vegetation, since these areas are characterized by greater density in prey.
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Οικολογία ενδιάμεσων μεταναστευτικών σταθμών του Κοκκινοκεφαλά Lanius senator, κατά την ανοιξιάτικη μεταναστευτική περίοδο
