Three different species of “white-rumped black swifts” occur in the Garden Route: Little Swifts, Horus Swifts and White-rumped Swifts. At first glance it might seem hard to tell the swifts apart, but take a second look and you might start to spot the differences.
When separating the three species, there are some important clues to consider. Firstly, listen to their calls. Little Swifts call loudly, and do so quite often. Their call is also very distinctive, and once you get to know it, you can easily identify them by their call alone. Even though the calls of White-rumped Swifts and Horus Swifts are very different to that of the Little Swift, they are, unfortunately, very similar to one another. So listening to their calls only really works to single out the Little Swift.
Secondly, look at their habitat and their inter-specific interactions. White-rumped Swifts are “pirates”, stealing the nests built by Greater (and Lesser) Striped Swallows. Therefore, White-rumped Swifts are often found in association with these swallows. These swallows nest under the eaves of buildings and the overhangs of rocks, and that relates directly to their habitat: areas where people live, as well as cliffs and gorges. Horus Swifts make their nests in a hole in a river bank. Be on the lookout for them along rivers with steep banks such as the Gourits River.
Thirdly, look at the shape of the tail and the shape of the white rump. It’s quite simple: Little Swifts have a square tail and a large square-shaped white rump; Horus Swifts have a forked tail and a large square-shaped white rump; and White-rumped Swifts have a forked tail and a smaller, sickle-shaped white rump. Each combination of tail shape and white rump shape is, therefore, notably different. Keep all of this in mind and you will no longer struggle to identify these jolly swifts.
Photo of White-rumped Swift: Geoff McIlleron