Present situation of the Barred Warbler in Ukraine and its biology according to researches in Sumy region. - N.P. Knysh. - Berkut. 14 (1). 2005. - P. 99-110.
Literature and own data about number of the Barred Warbler in Ukraine are analysed. Approximately till the beginning of 1980s gradual number increasing were observed in majority of regions, but during the next decades it was multiple decreased. Certain prosperity of the species is established for east Ukraine (Kharkiv and may be Donetsk regions). In the whole territory of the forest zone of Ukraine it is rare. The Barred Warbler has flat-wave type of long-term number fluctuations with local raisings and recessions. Breeding ecology was studied in forest-steppe part of Sumy region (NE Ukraine) in 1969–2005. Settlements of the species are mosaic, they are located as a rule in overgrowing glades of oak forests. 0,32–1,0 pairs/ha in 1970–1980s and 0,10–0,29 pairs/ha in 1995–2005 were counted here. In other habitats the population density is lower. The first males arrive in spring on 29.04 (1994, 1995) – 10.05 (1986, 2003), on average 6.05 ± 1,0 day (± SE, n = 14). 90 cases of breeding were observed. Relations with 25 plant species were recorded (Table 1). First nests with started clutches were found 11.05 (1996) – 22.05 (1980), last ones – 15.06 (1980) – 28.06 (1984), on average 17.05 ± 3,3 (n = 8) and 21.06 ± 6,2 days (n = 4). Number of begun clutches (n = 70) by ten-days since 2nd ten-day of May: 11 (15,7 %) – 37 (52,9 %) – 18 (25,7 %) – 2 (2,9 %) – 2 (2,9 %). Full clutches had 3–6, on average 4,84 ± 0,07 eggs (n = 61). May clutches (n = 40) are larger than June ones (n = 17): 4,95 ± 0,08 against 4,53 ± 0,17 eggs. Measures of 53 eggs from 13 clutches: 20,77 ± 0,11 x 15,56 ± 0,06 mm (limits: 18,2–23,2 x 14,3–16,5 mm). 20 of 24 pairs successfully raised youngs (83,3 %). Broods had 3,90 ± 0,28 (n = 21) hatchlings and 3,85 ± 0,27 (n = 20) fledglings. A breeding pair had on average 3,85 ± 0,27 hatchlings and 3,21 ± 0,38 (n = 24), 79,6 % è 74,8 % from number of eggs laid (n = 103). The largest losses of offsprings occur during brooding (69,2 %) and feeding of nestlings (19,2 %). In the study area factors, that can greatly influence on the breeding success, are absent. [Russian].
Key words: Barred Warbler, Sylvia nisoria, Ukraine, number, ecology, breeding, clutch, migration.
Address: N.P. Knysh, Sumy Pedagogical University, Dep. of Zoology, Romenska str. 87, 40002 Sumy, Ukraine.