South African Cliff Swallow colony

These days the South African Cliff Swallow should be more appropriately called South African Bridge Swallow! Some 20 km from our home village these swallows nest under a road bridge with about 100 of their gourd-like nests, each said to be constructed with between 1,300 and 1,800 mud pellets, and each weighs nearly 1 kg. The nests adjoin and overlap each other.

Once egg laying has started and the first chicks hatch several pairs of White-rumped Swifts harass and chase the swallows out of their nests, eject the eggs and even chicks if they are present. Nests taken over by the swifts are easily identified by feathers around the short entrances. Although both Cape and House sparrows will take over swallow nests we have never observed it at this location. For the latter it is too far from human habitation and although the former are around we have never seen them at this nest site.