The biology of the Alpine accentor Prunella collaris. IV. Maintenance activities and their clusters from late autumn to early spring. 20 year observation

Abstract

The maintenance activities and seasonal rhythms in behaviour and behavioural clusters of Alpine accentor (Prunella collaris) were studied between 1984 to 2003 at Malinô Brdo, Great Fatra NP, a ski resort in the West Carpathians, Slovakia. The following episodes of behaviour were recorded: feeding, standing (sitting alert), sitting (drowsily), preening, flights, calls and songs. Notes on behaviour were simply written or dictated onto tape. One minute of an activity of one bird constituded one field sample. In total, 21 282 samples of feeding, 1699 of preening, 18 411 of seating, 2417 of standing, 3775 of songs or calls, and 1630 of flights (longer than 100 metres) were collected. Daily activity of accentors ranged frorn 8 hours per day in late December to approximately 11 hours per day in April. During November, daily feeding schedules were bipolar, with peaks in early morning and at two o´clock p.m. Rest periods rapidly increased during December. Resting was accompanied by the disappearence of vocalisation and a rapid reduction in preening. In January, the accentors exhibited a series of activities comparable to the structure of behaviour in November. The increased length of daylight in February likely induced hormonal activity in birds, and the amount of time devoted to singing rapidly increased. Subsongs often alternated with preening. In March, throughhout a day, birds displayed a mixture of many different kinds of activities including singing, preening, short flights, and standing alert. In April, accentors exhibited a series of activities that corresponded to pre – mating behaviour. Generally, birds were more stressed during feeding on cloudy than sunny days. The association between flocking and resting without additional activity, such as preening, supports the notion of a link between flocking and an efficient use of energy during winter.