Lesser striped swallows (Cecropis abyssinica) are one of our most common backyard residents. Every evening when the light conditions are less harsh, dozens of them land in the acacia trees, chirping away. They seem to prefer certain perches, and these two swallows always situate themselves at the end of a particular branch. Usually one will land alone and call repeatedly to the other. The second lands soon afterwards, usually with a beak full of a globular piece mud. Lesser striped swallows build their nests out of mud under rocky outcrops, sturdy branches high in trees, and in this case on human dwellings. They are well hidden inside their mud lairs, and unlike the swifts, we are rarely able to spot them inside their nests.