A 2023. decemberi vízimadár-felmérés eredményei a Balatonon és a környező vizesélőhelyeken

Waterbird census was carried out on 59 survey plots around Lake Balaton and its surrounding wetlands on 16th December 2023, like in previous years (KOVÁCS, 2008a, 2008b, 2008c, 2013a, 2013b, 2013c, 2013d, 2015, 2023a, 2023b, 2023c, 2023d, 2023e; KOVÁCS & HAJDU, 2015a, 2015b; KOVÁCS & BRUCKNER 2022a, 2022b, 2022c, 2025a, 2025b, 2025c, 2025d) by BirdLife Hungary South-Balaton Local Group. A total of 49 waterbird species from 10 orders and 12 families were observed (Table 1). The Great Cormorant was the most numerous species (>9,200 individuals), followed by the Greater White-fronted Goose (>8,900), the Eurasian Coot (>8,600), the Goldeneye (>6,400), the Mallard (~4,900), the Common Pochard (~4,200), the Tufted Duck (>4,000), the Blackheaded Gull (~3,800) the Greylag Goose (~3,500) and the Yellow-legged/Caspian Gull (>3,200). All of these species were also significant throughout the survey area. A notable count was also recorded for the Great Crested Grebe, with more than 900 individuals observed. In fishponds and marshes, the dominant species (those with a dominance value D > 5%) were the Greater White-fronted Goose, Greylag Goose and Black-headed Gull. On Lake Balaton itself, the dominant species were the Great Cormorant, Eurasian Coot, Goldeneye, Mallard, Common Pochard, Tufted Duck and Yellow-legged/Caspian Gull. The highest number of individuals (~10,600) was recorded at the Irmapuszta fishponds, but significant aggregations were also observed at Szántód (>8,400 individuals) and Zamárdi (>6,000 individuals). Additionally, more than 1,000 waterbirds were recorded at 11 other survey locations (Table 2 and Map 1). The highest species richness was recorded at Szántód, with 19 waterbird species observed. Furthermore, at 22 additional survey plots, more than 10 species were recorded (Map 2). Several locally outstanding records were also made: 1,800 Great Cormorants at B.őszöd-B.szárszó; 1,350 Common Pochards, 2,800 Tufted Ducks and 3,100 Eurasian Coots at Szántód; 1,174 Common Pochards, 1,115 Yellow-legged/Caspian Gulls and 2,540 Great Cormorants at Zamárdi; 1,810 Great Cormorants at Tihany kikötő; 2,636 Goldeneyes at Tihany rév; a flock of 2,000 wild geese (mostly Greater White-fronted Geese) at Fenékpuszta; 1,200 Black-headed Gulls at Fonyód fishponds; 2,000 Greylag Geese and 8,000 White-fronted Geese at Irmapuszta fishponds. Species occurring at more than half of the observation sites (constancy C > 50%) included Mallard, Goldeneye, Mute Swan, Eurasian Coot, Black-headed Gull and Pygmy Cormorant, indicating their widespread presence in the study area. An interesting faunistic result was the occurrence of the following species: Common Shelduck (1 ind. at Irmapusztai-halastavak); Ferruginous Duck (8-5 ind. at Pálköve, Ábrahámhegy); Greater Scaup (70 ind. at Szántód); Common Eider (1 ind. at Bélatelep); Velvet Scoter (4 ind. at Balatonfenyves); Common Merganser (at 15 locations, with a maximum count of 75 individuals at Szántód); Red-breasted Merganser 1-4 ind. at Szántód, Ábrahámhegy); Black-necked Grebe (in numbers ranging from 1 to 4 individuals at 9 sites); Ruff, Dunlin and Common Snipe (1-12-14 ind. at Marcali-víztározó); European Herring Gull (11-1 ind. at Fonyód, Balatonfűzfő Föveny-strand); Red-throated Diver (2-1-1-1-1-1 ind. at Fonyód, Szántód, Zamárdi, Sajkod, Balatonszepezd, Révfülöp móló); Black-throated Diver (2-1-2-6 ind. at Balatonszárszó, Balatonföldvár, Szántód, Zamárdi, respectively).