Habitat preference, feeding distance and flight direction of cattle egrets (Bubulcus ibis) in the central Free State.

Abstract

In the Free State, two thirds of all actively feeding cattle egrets (Bubulcus ibis) were observed in open grassland habitats. If the birds that fed in association with hosts are considered separately, the dominance of grassland, especially short grass, is even higher. By contrast, cattle egrets that fed independently of hosts showed a clear preference for tall grass and edges of water body. Marked differences in habitat use between cattle egrets that fed in the presence or absence of hosts even occurred on a temporal basis during the course of the day. More than three quarters (78,6%) of all cattle egrets observed in the vicinity of the Soetdoring Nature Reserve fed within a radius of 15 km of the breeding colony. Depending on the time of the year, significant changes occurred in the general flight direction from and to the colony. Positive correlations were obtained between the outward and return flights, but not between the general flight direction and prevailing wind direction.