Roosts and roosting observations of the Grey Starling Sturnus cineraceus in Karuizawa, Nagano

Abstract

1) In the breeding season, March to June in 1960 and 1961, during which period observations were made, six small roosts, 24-60 birds each (only once 397 birds on June 23 possibly increased by young birds) were found scattered.
2) Roosts were found usually, but not always, at places where there was little traffic during the night.
3) Birch was most often used as roosts but larch and cherry trees were also used.
4) During the breeding season they entered directly into the roosts, coming back at sunset or as late as 30 minutes after.
5) It may well be that roost size is selected according to flock size as Kuroda has suggested.