Damian Wiehle, Grzegorz Neubauer
Ornis Polonica 2010, 51: 195–203
https://doi.org/10.12657/ornis.2010.3.2
Abstract: The paper presents results of year-round surveys of three species of non-breeding large gulls in the Vistula River Valley, Małopolska region (S Poland). 522 field surveys were conducted between 2001 and 2008 resulting in 26 110 large gulls recorded in total. The mean number of large gulls per survey increased significantly during 8 years of the study, which was caused mainly by the increase in size of winter concentrations. The wintering population of large gulls in Małopolska is estimated at 2 000–4 000 individuals in recent years. Throughout the year the dominant species was Caspian Gull, which constituted 90–99% of all gulls. Herring and Yellow-legged Gulls were much less numerous, with the former occurring mainly during winter (up to 12 ind. at one site), while the highest numbers of the latter were found in summer–autumn (up to 41 ind.), a patterns similar to that recorded in central Poland. The Caspian Gull dominance over the remaining species is much more distinct in Malopolska compared to central Poland.
