Ecological islands are patches of isolated, adjacent, often contrasting, ecosystems. Small forested areas, tree stands, shrub lands in a rural or urban areas are often classified as ecological islands. In Wielkopolska, many parks located around palaces, castles and mansions, e.g. park-arboretum in Gołuchów have such a status. The author presents the related problems using the Koszuty mansion and park as an example.