Ravens, Corvus corax (L. 1758), nesting on high-voltage transmission line pylons in Croatia

This paper presents the first data on the occurrence of nesting of ravens Corvus corax on transmission line pylons in south-eastern Europe, based on research in Croatia. Field-work was carried out in the period 1995200 1, in the area of eastern Croatia. By 2001, 93 breeding pairs of ravens were nesting on pylons over the 3 80 kin length of transmission lines under observation, comprising 14 surveyed routes. The breeding population increased over the period of seven years to a population density of 2.45 pairs per 10 kin of the line, which is the highest recorded in the world, for ravens breeding on electricity pylons. Ravens breeding in eastern Croatia often leave a particular pylon and/or change the nest position on the pylon in a subsequent year. Evidence suggested that some ravens may disintegrate their nests on the pylons, after their young have fledged.