I am only a sometime-ornithologist and one that looks mainly at dead birds. I don't know the real reason why mynas appear bald-headed at times. Our local myna expert, Dr Kang Nee, noted this phenomenon of botak (Malay for bald-headed) Common Mynas (Acridotheres tristis) when she studied them in the late 80s and early 90s. She noted that birds that have their crown feathers actually do not have the yellow skin on the head. It's only when the feathers are gone that the skin turns yellow. Why? Don't know. Did the feathers drop off because of moult or fighting? Don't know. She never obtained any observations even though she spent several years studying and radio-tracking them in the wild and breeding them in captivity.I have also written to the world's leading sturnid expert, Dr Chris Feare many years ago about botak mynas. He knew about them but couldn't offer any explanations either.
I think it might not be typical moulting, otherwise all Common Mynas would have the botak head at every moult cycle, which is usually once a year, and you should see a very high percentage of botak birds in the myna population.
Do mynas that are timid and smaller get pecked on the head until they are botak or do birds become more timid after they become botak? I have no answer. I wish I could lay my hands on some of these botak birds so that we may learn something from them.
Contributed by Wang Luan Keng in response to queries about these strange birds
its not my theory, but something i have heard/read and always assumed to be the truth till this blog entry.
ReplyDeletethe feathers drop because of illness or stress.
could it be a version of avian 'Male Pattern Baldness?" aka 'Mynah Pattern Baldness'?
hmmmm strange..
Are any feather mites observed in the collared individuals by any chance (unlikely since it was not mentioned), since the head cannot be preened effectively, mites could be a reason, or some nutrient deificiency; since I came to Singapore, I ve seen mynas very common in food centres, where they have a diet that is very different from their natural diet (which comprises of insects which have proteins which constitute basically the hair structures (keratin). This cooked food might not have enough protein supplements. So protein deficiency could be one reason, Are mynahs inhabiting lawns/natural habitats observed with such baldness ? It would be interesting to analyze hair samples across different individuals !
ReplyDeleteMy 2 cents worth was an actual sighting of the ever resourceful mynah trying to get their food in out of reach area. Thus craning their neck through fences and other obstacles, some of these birds tend to lose their head feathers. As to protein diet, well, one should come to Benoi Place Kopitiam, there the mynah feed on anything and everything - but they still maintain their full crown! BTW - botakness not restricted to mynah, but also to pigeon, and chicken kept in cages. TC Tan
ReplyDeletewell, deficiency and feather mites are only two of many possibilities :-) Physical abberation counts to three
ReplyDeleteon the contrary! I owned a Myna as a child and I have another one now. His name is Apu (named after the shop keeper in the simpsons). Anyway, I found that when they are still very small, they get all their feathers and the head feathers are the last to grow! I have also found that they are very clean and tidy birds and spend alot of time cleaning and checking their feathers.
ReplyDeleteIt is not my theory,
ReplyDeletei have seen many such balded mynas in Aligarh-UP-India, during the starting of winter,i am not sure that it is due to cold ,
but many individuals were seen as balded in the season.
See the discussion happening at
ReplyDeletehttp://www.facebook.com/groups/indianbirds/?view=permalink&id=10150269536017411
i have a 8 month old common mynah,and have been worried as in the last week he has lost his head feathers..he has been thru a molt and hoped it was just that,however now i've read this i'm happy that its nothing serious :)
ReplyDelete