Jelentés a Gönyű-Szob közti Duna-szakasz (1791 – 1708 fkm) 2021. augusztus – 2022. április időszakának vízimadár felméréseiről

• Published in: Magyar Vízivad Közlemények
• Main Author: Faragó, Sándor
• Format: Article in Journal/Newspaper
• Language: Hungarian
• Published: 2023
• Subjects: Olor; Duna; Haliaeetus albicilla; Larus canus; Mergellus albellus; Sterna hirundo; Pandion haliaetus
• Online Access: http://publicatio.uni-sopron.hu/3232/; https://doi.org/10.17242/MVvK_37.17; http://publicatio.uni-sopron.hu/3232/1/magyar-vizivad-kozlemenyek-2023-37-297-303.pdf

Report on the waterbird censuses of Danube River between Gönyű and Szob (River kms 1791 – 1708) during the period August 2021 and April 2022. Based on the results of the waterfowl counts (shown in Tables 2 and 3) completed during the 2021/2022 season in the section between Gönyű and Szob of the Danube river, we recorded the largest number of waterbirds (n=16 2014) in January, while the smallest total number of birds occurred in September (n=324). The daily water level of the Danube River on the observation days shows Table 1. We observed the highest number of species (18 species) in November, while in August we saw only 6 species. During the 9-month study, we observed 29 species. Species that only appeared occasionally or in small numbers (˂100 per observation) included Cygnus olor (max. 80), Anser anser (max. 1), Anser albifrons (max. 65), Clangula hyemalis (max. 2), Mergellus albellus (max. 9), Mergus serrator (max. 2), Aythya fuligula (max. 95), Spatula clypeata (max. 1), Mareca penelope (max. 34), Anas crecca (max. 40), Tachybaptus ruficollis (max. 3), Podiceps cristatus (max. 2), Gavia stellata (max. 3), Egretta garzetta (max. 1), Ardea alba (max. 39), Microcarbo pygmeus (max. 1), Pandion haliaetus (max. 1), Haliaeetus albicilla (max. 5), Larus cachinnans (max. 8), Larus marinus (max. 1) and Sterna hirundo (max. 1). Species that appeared in larger numbers and quantities (˃100 per observation) were as follows: Bucephala clangula: 0–1176, Aythya fuligula: 0–95, Mergus merganser: 0–186, Anas platyrhynchos: 23–11 068, Ardea cinerea: 0–124, Phalacrocorax carbo: 7–745, Larus michahellis: 12–943, Larus canus: 0–1198 and Croicocephalus ridibundus: 9–3020, Figures 1 present the dynamics of common species. There are 3 known Great Cormorant nesting colonies in the studied section of the Danube; in 2022, 290–330 pairs nested there. There were 115–125 pairs of Grey Heron (Ardea cinerea) which, like the Great Cormorant, also nests in 3 colonies. On the Süttői Island are nesting 5 pairs of Black-crowned Night Heron ...