Oxpeckers never get that much attention, but they are fascinating to watch. I spent a couple of hours on the river bank recently, watching them interact with their host hippos and with each other.
They move from host to host, cleaning the exposed skin and wounds and feeding on ticks and other parasites. When a hippo turns over in the water, they move quickly to the newly-exposed skin to enjoy the parasites that had previously been concealed. In this way, they often congregate in large numbers. It was the middle of the day by this stage, so many of the birds were ‘gaping’ to cool down, giving the impression of a choir singing!
Here, 2 (slightly larger) Yellow-billed Oxpeckers out-compete their Red-billed cousins for the cleaning rights to an open wound on this hippo’s back.
Sometimes there are even fights between con-specifics!