Foraging alone, in pairs or in small flocks, sometimes with other species, the black-faced woodswallow typically hunts from the air, soaring over grassland searching for insects. Sometimes prey may be located and pursued from a perch, with lower perches chosen in windy weather. The black-faced woodswallow consumes a wide variety of invertebrates, but during locust plagues it becomes a specialist predator, taking only locusts (2). Although its diet is primarily insectivorous (2) (3), this species has also been seen feeding on Xanthorrhoea seeds (3).
The breeding season of the black-faced woodswallow is from spring to early summer, mainly October and November (2) (3). However, eggs have been recorded in all months, with the exception of June (2). Usually breeding co-operatively in groups of up to six (2), the black-faced woodswallow builds a cup-shaped nest of fine roots, twigs and grass (2) (3). The nest is placed approximately three to five metres above ground in a tree, shrub or artificial structure such as a telegraph pole. Clutches of up to 5 eggs are laid, although more commonly 3 to 4, and the eggs are usually incubated for 13 to 14 days. Incubation is carried out by all individuals in the mixed-sex co-operative group (2).
Black-faced woodswallow eggs are variable in colour and markings, but are normally bluish-white with reddish-brown blotches and spots of purplish-grey. The eggs are visibly more marked towards the wider end (3). The nestling period of the black-faced woodswallow is around 18 days, during which time the chicks are fed by all members of the group (2).
The black-faced woodswallow is a sociable species, sometimes roosting in groups of hundreds of individuals, huddling together to keep warm and save energy. More dominant birds are often found towards the centre of the clusters, burning less energy than those on the outer edge (7).