Prokofyeva, I.V. (2006): Peculiarities in behaviour of black swifts during the nesting period (Russian). Russian Journal of Ornithology 333
(APUSlist No. 3780)
by IGOR FEFELOV
Prokofyeva conducted researches on Black Swifts in the Leningrad region, mainly towards the south but also near Vyritsa, during 1985-1989 and 1999-2006. 63 nests were observed, they were all in areas of human occupation. Although there were reports about Black Swifts' presence in forests, no nests were detected there.
The nests were often found in groups. In 1969 we found two nests in artificial nest boxes at one tree in an altitude 3.5 and 6 m.
It was found that some Swifts occupied nest boxes, which already contained nests of other bird species. Three such cases were found, a Swift in 1988 in a Great Tit's nest, incubating two Swift eggs and one Great Tit egg. In another Swift nests there were dead chicks of Eurasian Starling, and in a third case, four Eurasian Starling's eggs were found in a Swift's nest in an artificial nest box.
The altitude of the Swift nests was low, from 2.5 to 6 m. Two were found in boxes at 8 m, and one at 18 m in a woodpecker's hole in an aspen tree (Populus tremula).
In one of the nest boxes which was occupied by Common Swifts some unusual construction material was found, namely many thin layers from the bark of the Common Pine (Pinus sylvestris).
Following clutch sizes were found: 2 eggs in 30 nests, 3 eggs in 2 nests and 1 egg in one nest.
In three nests damaged eggs were found (one in a nest and both ones in other two nests), which had forced the Swifts to make a prolonged incubation.
Several times the expulsion of eggs was recorded. On 20 July 1965 Prokofyeva observed that in one nest the parent birds had practically stopped feeding the chicks which were 10-11 days old. They did not bring a food during 6 hours; and due to this, the chicks died.
The shortest overall period of daily feeding activity lasted 14 h 15 min, and the longest 18 h 31 min. In 1984, it was observed that two eggs were laid in one nest within 24 hours.
The author did not observe food transport events after 5 August, but there are notes of late broods from that region in the literature, which record them as occurring until the end of August.
© APUSlife 2008, No. 3850