Abstract
Colour rings with alphanumeric codes have been used on the Lesser Spotted Eagles since 2000. On April 24, 2007 an eagle with a yellow ring I9 was photographed in the "Ondavská vrchovina" highlands near the village of Lieskovec in Humenné district. It was found out that the eagle was ringed on the same site on July 4, 2002 as a chick on the nest. After further observations the adult male was spotted feeding its chick in the nest, which was located only 130 m from the one it hatched at. If it could be proved that the female at the nesting site, which has been regularly surveyed since 1985 has not changed, nesting of a son and a mother could not to be ruled out in this case.