“These were taken late in the evening in my neighbourhood, hence grainy.
“A pair of Common Mynas (Acridotheres tristis tristis) was bringing food to young. Notice the one is almost completely bald and the other is also a bit affected. Appears that this baldness is not an obstacle to mating and having young.
“The nest is one I have posted earlier – in a junction box for an electrical system LINK. It is often used and much material added over the years. Often hotly contested during nesting period.”
Dato’ Dr Amar-Singh HSS
Canning Garden Home, Ipoh, Perak, Malaysia
19th April 2011
Note: According to Clark (2004, p3.38), “Once in a while, a bird turns up with very few feathers on its head. The head may be bare, with ear opening clearly visible, or may have a short layer of barely emerging feathers. Generally the entire head from the neck up is bare, but sometimes just patches of feathers are missing. These “bald” birds… are seen mostly in the fall, …are probably juveniles born earlier in the year undergoing their first prebasic molt. For some unknown reasons, some of these birds drop all their head feathers at one time and quickly regrow them, rather than losing and replacing them a few at a time. Why birds occasionally become bald at other times of year, and why adult birds are sometime affected, remain a mystery. It’s possible that some type of atypical molt causes baldness in these birds, or that an infestation of feather lice or feather mites is responsible.”
Clark, G. A. Jr. (2004). [‘Form and function: The external bird.’]. Pp. 3.1-3.70 in Podulka, S., Rohrbaugh, R.W. Jr & Bonney, R. (eds.) Handbook of bird biology. Ithaca, NY: The Cornell Lab of Ornithology.
Many thanks for that. Was puzzled by a low res photo sent to me for ID of a bird in Melbourne, Australia, that had the plumage of myna but a head that looked more like a friar bird! Looking at this character here the image sent to me is very clearly a myna suffering exactly the same problem! Seen many thousands of mynas here, but never a bald one before!
This condition is not very common here…