Covas R, Huyser O, Doutrelant C. 2004. Pygmy Falcon predation of nestlings of their obligate host, the Sociable Weaver. Ostrich 75:325-326.

The Pygmy Falcon Polihierax semitorquatus is a small, raptor which does not build its own nest. In southern Africa it is dependent on the communal nest masses of Sociable Weavers Philetairus socius to breed and roost in. This falcon usually feeds on small reptiles, large insects and only occasionally on small birds and rodents. There are very few reports of Pygmy Falcons preying on Sociable Weaver nestlings, and these authors report some new records.

A falcon pair was observed at Benfontein Game farm near Kimberley.

• In the Mar-Apr 2000 breeding season a falcon was seen leaving a nest chamber with a chick. The chamber had contained 2 chicks of 9-10 days and remains of the second were found nearby, suggesting the falcon fed on both.
• In Oct 2000 a female falcon was seen taking 2 chicks, one from each of 2 chambers; these chacks were close to 5 and 15 days old.
• The authors also refer to Colin Sapsford's unpublished study near Nossob, where Colin collected pellets of the falcons from 1984–1992. Birds (presumably mostly Sociable Weavers) constituted less than 4% of the falcons' diet, but this could be an underestimate.

Recently Jacky Spiby photographed a Pygmy Falcon feeding on a Sociable Weaver nestling at Benfontein, and submitted a PHOWN record.
Some more records may be seen here.