Behaviour and daily activity of the squirrel Sciurus ingrami in a secondary araucaria forest in southern Brazil

Abstract

A study on the behaviour of a population of squirrels, the "serelepe" (Sciurus ingrami), was conducted in a secondary araucaria forest in southern Brazil. Forty-three squirrels were marked and observed between 05:00 and 18:00 daily. The largest number of males were trapped during the winter, coinciding with an increase in the number of agonistic encounters and mating chases. Two peaks in occurrence of trapped pregnant females were found, one during the winter and the other in the summer. The population density was 0.89 squirrels/ha and the mean area occupied by males was larger during the winter mating period, decreasing gradually during subsequent seasons. The diurnal activity of S. ingrami exhibited bimodal curves in all seasons, with one peak in the morning and another in the afternoon. During the winter, the morning peak was greater in amplitude than during the other seasons. In the spring and summer, a marked increase in the activity of the squirrels during the hottest hours occurred. The morning peak of activity occurred earlier in the spring and summer and later in the autumn and winter. The daily time spent inrest, displacement, feeding, and maintenance showed seasonal variation similar to that shown by other sciurids.