bald blackbird

dickybird · #1 (**permalink**) 08-10-2009, 12:42 PM

i have a blackbird visiting my garden that is completely bald from the top of its head to just above the wings--it looks as though someone is unravelling its jumper! the rest of its plumage appears fine and it has all its tail and wing feathers. it appears well and not noticeably affected by its state.
i wonder what may be causing this condition? ive seen blackbirds in moult but this seems extreme.
any ideas please?

dickybird

Dutchess · #2 (**permalink**) 08-10-2009, 12:50 PM

Sounds like a mite infestation to me, db. Apparently, this is being talked about on the Autumnwatch message boards. You may want to pay them a visit.

hth.

D.

Jason Claxton · #3 (**permalink**) 08-10-2009, 12:52 PM

Hi ,I just googled bald blackbirds on the internet,quite a few on there ,people variously suggest mites ,stress and moulting,but I do not know for certain.

Jason

Dutchess · #4 (**permalink**) 08-10-2009, 12:56 PM

Apparently, a mite infestation can give the affected bird the appearance of "looking like a vulture"! Sounds very similar to the unravelling woolly scenario described by db...

dickybird · #5 (**permalink**) 08-10-2009, 01:00 PM

thats interesting,duchess-will follow with interest.

thanks too,jason

dickybird

wonder if theres anything that can be done about it? ive got numerous b.birds in the garden at the mo(for windfalls) id hate to see them all affected. i presume they wont survive the cold...?

Jason Claxton · #6 (**permalink**) 08-10-2009, 01:12 PM

Another site suggests that when birds are stressed,feathers stop growing,and that fungi and other microbial factors can break them down.Would it be a Black vulture then(sorry about that

).Hope he does survive.

Jason

heliart · #7 (**permalink**) 08-10-2009, 01:14 PM

Interestingly, our local blackbird went totally bald about a month ago - after looking very scraggy through most of the Summer, but with a steady diet of meal worms he's now looking lovely - so we put it down to a simple case of moulting.

valleyforge · #8 (**permalink**) 08-10-2009, 01:27 PM

It's not that uncommon DB ... and there are at least a couple of previous threads on this forum complete with photos (of blackbirds).

In my own experience, this appears to occur (or at least is observed) more frequently in male blackbirds than in any other species, although also occasionally seen in corvids and in some finches ... male chaffinches in particular.

Normally feathers are moulted in a sequence, so that dropped feathers are replaced by new ones ... apart from appearing untidy for a while, there usually isn't any apparent 'baldness'.

However, sometimes ... and for a variety of reasons ... the normal moulting pattern can become suspended or arrested, such that when it resumes there is a rapid loss and replacement of the plumage. To the casual observer, this is much more noticable when it involves the feathers on the head and neck of a bird.

Because we work 'up-close and personal' with those birds that are in our long term care, I can vouch that the condition isn't caused by the presence of mites or any other exoparasite ... nor is it due to any apparent dietary deficiency (although those are quite possibly factors in some birds).

Since it appears to occur more often in male birds than in females, I suspect that some hormonal imbalance might be implicated.

In some birds that have exhibited this condition, all moults in successive years have occurred normally, so the fact that it has happenned once does not predispose that it will occur again in the same bird.

At the moment, we have a magpie who is in the process of sprouting all new feathers on the head and neck, having spent last week resembling a mini-vulture ... in another week he'll have regained his overall glossy plumage and be well insulated again for the winter ... so thankfully we won't have to resort to knitting him a wee balaclava.

TeresaW · #9 (**permalink**) 08-10-2009, 03:44 PM

Quote:

Originally Posted by valleyforge

Since it appears to occur more often in male birds than in females, I suspect that some hormonal imbalance might be implicated.

That's interesting. Could this be an effect of climate change, especially as we have just had an indian summer and a seemingly longer nesting season? Perhaps resulting in a longer crossover from 'breeding mode' to 'prepare for winter' mode?

valleyforge · #10 (**permalink**) 08-10-2009, 04:19 PM

It's possible TeresaW ... but I have suspected it might be more to do with the bird having been unmated that season ... although it doesn't necessarily reoccur in the same bird if it remains unmated the following season ... so probably not the whole answer.

It's only a theory though ... and since it is only a passing phase that doesn't appear to cause the birds any undue or lasting stress, we've not seen any reason to worry unduly about it when it occurs.

The birds seem a little more self conscious and a little less outgoing than normal, but that's about all ... unless it's raining when they definitely prefer to stay under cover.

Having a bit of a balding pate myself, I can understand that perfectly.