This is a common reed frog (Hyperolius marmoratus) found in an ornamental pond at the Satemwa Tea Estate. This photo shows the in-between colour. It started with a completely white back, and then must have slowly gotten annoyed with me, because after 10 minutes, its back had gone quite black, except for the white stripe down the middle. If I had to guess, while white it mimics a bird dropping, and when black, it was very hard to see over the dark pond...
