NESTING OF THE COMMON TERN (STERNA HIRUNDO) IN THE SILT FIELDS OF THE WATER TREATMENT FACILITIES OF KHARKIV CITY IN 2020 – 2021

• Published in: Біорізноманіття, екологія та експериментальна біологія
• Main Author: Мамедова, Ю. П.
• Format: Article in Journal/Newspaper
• Language: Ukrainian
• Published: Biodiversity, ecology and experimental biology 2022
• Subjects: The Common tern; phenology; treatment facilities; крячок річковий; гніздування; фенологія; очисні споруди; Common tern; Sterna hirundo; Black-headed Gull; Larus ridibundus
• Online Access: http://journals.hnpu.edu.ua/index.php/biology/article/view/3835; https://doi.org/10.34142/2708-5848.2021.23.2.05

The nesting biology of the Common tern (Sterna hirundo L.) in the silt fields of water treatment facilities was studied in Kharkiv in April-August of two seasons, 2020 and 2021. 228 individuals of birds were identified, features of 135 nests and 172 chicks were studied. The Common terns inhabit three areas within the studied territory, one of them is inhabited for two years (from 10 to 90 pairs). The first eggs in the clutches were found in the second decade of May, at the average daily temperature of +5±1.76°C at night and +20±0.89°C in the daytime in 2020 and at + 14.9 ± 3.08 ° in the daytime and +5 ± 2.76 ° C at night in 2021. The egg laying by the Common tern reached a peak at the end of June - beginning of July in 2020 and at the end of May to beginning of July in 2021. The difference in the timing of the beginning of reproduction between the Common tern and the Black-headed gull (Larus ridibundus) was, on average, 37 days. The first chicks in the nests were registered in the first decade of June (5.06.2020; 10.06.2021). The first flight chicks were observed at 2.07.2020 and 12.07.2021. Before migration, young birds gather in small flocks of 10–15 individuals. There are two types of nests observed. The first is typicaly built as indentations in the silt with plant litter (51.5%; n = 135) and nests, which were composed of colored tubes, the remains of plastic bags (45.5%). The second type, ‘atypical’ nests (3.0%) are built on the cellophane bag. The average size of the clutch is 2.77±0.43 (1-3) eggs, with a brown and greenish-gray tint in the color of the main background of the shell. The individual was registered, possessing two rings of the Israil Atlit Sait – Pans (27.04.2020, coordinates 32 ° 42'00 ”N 34 ° 56'00” E.) Досліджено гніздову біологію крячка річкового (Sterna hirundo L.) на мулових полях водоочисних споруд м. Харкова у квітні-серпні 2020-2021 років. Виявлено 228 особин птахів, описано особливості розміщення 135 гнізд та 172 пташенят. Крячки річкові заселяли три ділянки, одну із яких протягом ...