Leucistic Speckled Mousebird at Grootvadersbosch Nature Reserve

While birding at Grootvadersbosch Nature Reserve on Saturday I was surprised to bump into an albino Speckled Mousebird. The bird was seen close to the reserve office – see map below – and was very obvious amongst its grey team mates.

Grootvadersbosch map reduced

It wasn’t particularly obliging, but you get the idea from the photo below.

Speckled Mousebird albino

I gleaned the following from Wikipedia:

Albinism in birds is rare, occurring to any extent in perhaps one in 1800 individuals (Terres 1980). A bird that is albino (from the Latin albus, “white”) has white feathers in place of coloured ones on some portion of its body.

Four degrees of albinism have been described. The most common form is termed partial albinism, in which local areas of the bird’s body, such as certain feathers are lacking the pigment melanin. The white areas may be symmetrical, with both sides of the bird showing a similar pattern. In imperfect albinism, the pigment is partially inhibited in the skin, eyes, or feathers, but is not absent from any of them. Incomplete albinism is the complete absence of pigment from the skin, eyes, or feathers, but not all three. A completely albino bird is the most rare, lacking any pigment in its skin, eyes, and feathers. The eyes in this case are pink or red, because blood shows through in the absence of pigment in the irises. The beak, legs, and feet are very pale or white.

Completely albino adults are very rarely spotted in the wild. They are likely easier targets for predators because their colour distinguishes them from their environment. Falconers have observed that their trained birds are likely to attack a white pigeon in a flock because it is conspicuous. A complete albino often has weak eyesight and brittle wing and tail feathers, which may reduce its ability to fly. In flocks, albinos are often harassed by their own species. Such observations have been made among red-winged blackbirds, barn swallows, and African penguins. In a nesting colony of the latter, three unusual juveniles—one black-headed, one white-headed, and one full albino—were shunned and abused by companions. [more here]

What was very striking about this individual was how obvious it was in flight – at first glance it looked like a cockatiel! The photo below is a rather embarrassing attempt at a flight shot, but you get the idea.

Speckled Mousebird albino flight

Based on what Wiki says regarding albinism in birds, I would say this is a completely albino individual. Any thoughts?

Correction: it has since been brought to my attention that this bird is probably leucistic rather than an albino.  You can read about the reasons here, but essentially the dark eye gives it away. A complete albino would have no pigment in the eye.

2 comments to Leucistic Speckled Mousebird at Grootvadersbosch Nature Reserve

  • David Jobson

    re – White speckled Mousebird

    I’m inclined to think that this bird is leucistic rather than albino – the eyes are dark and in albinoms should be pink.

    Have a look at Leucism in Wiki and see what you think!

    Love you site though – particularly as two years ago I must have missed the Tern colony when I went to Harold Porter and the penguins but did not know about the Terns!!!

    David Jobson
    UK

  • Thanks David – I’ve always understood that leucistic birds show partial original feather colouration, but perhaps this is incorrect. I’ll have to do some more research.

    Yes, the tern colony is not well known, however I’m sure Harold Porter and the penguin colony kept you entertained!

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