Publication Type: | Journal Article |
Year of Publication: | 1976 |
Authors: | Gyllin, R, Källander, H |
Journal: | Ornis Scandinavica |
Volume: | 7 |
Issue: | 1 |
Date Published: | 1976 |
ISBN Number: | 00305693 |
Keywords: | Coloeus, Coloeus monedula, Corvidae, Corvus, Corvus monedula, Sweden |
Abstract: | Jackdaws Corvus monedula roosting in the town of Örebro, Central Sweden, were studied from autumn 1956 to autumn 1961. Roosting occurred from mid-summer to March/April. Six distinct flight lines were used. The highest total, about 7,000 birds, was recorded in mid-winter. Maximum travelling distance was 35 km. Flights to the roost took place much earlier in relation to sunset in summer than in winter. In mid-winter up to 15 per cent of the day-time was spent flying to and from the roost. Persistent persecution had only temporary effect. A breeding-time roost outside Örebro was used from March/April to July. Hypotheses regarding the adaptive significance of communal roosting and of roosting in town centres are discussed. |
URL: | http://www.jstor.org/stable/3676179 |
Short Title: | Ornis Scandinavica |
Taxonomic name: