Monday 23 March 2015

Ruffled feathers, and worse

I first noticed this poor bird at the end of last year and took this photo on 2nd January.  As described in a previous post, it had abnormal body and tail feathers and discoloured wing feathers.  I sent pictures to the BTO but they didn't know what was wrong with it.

In a follow up post on 4th February the feathers looked worse but the bird was still behaving normally.

The last time I saw it was on 27th February, by which time it had lost its tail feathers altogether, plus a lot of body feathers.  I presume it died or was predated.



At the same time as the last photos above I noticed a similar but less severely affected bird in the garden but I didn't manage to photograph it until 8th March.  It still has fairly normal tail, head and wing feathers but deranged body feathers and a lot of missing feathers around its neck.  Like the other one it flies and feeds normally but it spends a lot of time preening, as if the feathers are irritating.  I have had a good look around on the internet and I wonder if these two birds might have a severe feather mite infestation.



This is the same second bird now.  It doesn't look significantly worse than two weeks ago and still behaves normally.





In recent days I have also seen this blue tit in the garden.  It has lost its tail, which happens, but its body feathers are abnormally fluffed up and it doesn't fly well.  It rarely gets on the peanut feeder but behaves like a dunnock, catching what the other birds drop from the feeder.  It also has an obvious bill deformity, so it not just a missing tail or just a feather problem.




And then there is this bird with a localised and rather different feather abnormality.  I don't know if all these problems are connected, or the cause of any of them.  If you know what they are please leave a comment.

5 comments:

  1. You seem to have an outbreak! Quite a stunning range of pathology!

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  2. If these birds do have a mite infestation which seems quite likely, how is it transmitted?

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    1. I'm not an expert Liz but from what I read it is direct bird to bird transmission without, for instance, an insect vector. It seems that there are a lot of different mites and most birds carry some so why these two are so badly affected isn't clear. I think the problem with the last two birds is different. The cause of beak deformities seems to be unknown but there must be a link with the feather problems in this blue tit. I'll keep my eye out for this last great tit and see what evolves.

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  3. How did you remedy the mite infection? It seems as though a Great Tit here in Denmark has also started to develop the same symptoms. Is there a cure?

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    1. There wasn't much I could do and I didn't treat it. I think low levels of mite infestation are fairly common and I still occasionally see a bird with a localised patch of damaged feathers. The transmission is likely to be bird-to-bird so if it was a big problem the solution is probably to stop feeding for a while.

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