Hennie van der Merwe was rather surprised when he recently observed a white Common Moorhen at the wetlands that form the Bird Paradise in Walvis Bay.
The sighting of this bird was extremely unusual since the normal Common Moorhen is slate-black with a dark olive-brown back and rump. Its legs and feet are yellow and the bill is a bright red with a yellow tip.
Although the first conclusion may be that the white of this particular Moorhen points towards albinism, upon closer inspection, the bird lacks the red eyes that are indicative of this genetic condition. Instead, this suggests that the bird is leucistic – a genetic disorder that causes its feathers to be white and the skin underneath to be pink. Leucistic skin does not contain melanocytes, i.e. pigment producing cells. In albinism, by contrast, these cells are present but unable to produce the pigment melanin.
Common Moorhens can be found all over Namibia where there are marshes, swamps, ponds, pans, rivers, streams, lakes and dams with fringing and emergent vegetation. They are associated with fresh water but occur along brackish waters on the Namibian coast. These birds are omnivorous, feeding on plant matter and invertebrates.
Author: Dirk Heinrich