Moulting Mishaps (1 Viewer)

It's that time of year when I guess we all see some extremes of Moult; the birds look odd to us, but I doubt they care

I thought I'd post two pics; one of a Jay, and one of a Blackbird. The Blackbird looks like it's escaped from a Sparrowhawk (I'm pretty sure it hadn't; no other missing feathers visible). The Jay is one of three with a head full of pin feathers. This doesn't trouble the birds, they still feed and fly normally.

Feel free to add any pics if you see any yourself... I might add more, or I might forget that I started this thread... it wouldn't be the first time

(Pics taken through double glazing, not that it matters for this)

Magpie with a 'bad hair day' . . .

Magpies and Jays do seem to look a bit of a mess during moulting

Interesting photos. This from the Cornell website--

"Each year FeederWatchers report several cases of bald-headed birds, mostly Blue Jays and Northern Cardinals.

One possible explanation for this phenomenon is an abnormal replacement of feathers (molt). Most bald-headed-bird reports occur in summer and fall, which are typical molting times. Many of these strange-looking birds may be juveniles undergoing their first prebasic molt, which produces the first winter adult plumage. For some unknown reason, the bald birds may have dropped all of their head feathers at once. Staggered feather replacement is the normal pattern.

Other cases of baldness may result from feather mites or lice, or some environmental or nutritional factor. But no one knows for sure, and the condition has not been well studied. Fortunately, new head feathers grow in within a few weeks."

I'm quite surprised that it's not been studied fully, Fred. Although I've seen no evidence of it affecting the bird (I doubt they care what they look like, and not many species can recognise their reflection ), I do wonder about it.

A few questions spring to mind:

Are these birds more likely to be noticed by predators? (IME, looking a bit different means more likely to be noticed by a predator)

Are these birds treated differently by other birds of the same species? (Breeding is over, so it shouldn't affect which mate they get, but do they get picked on?)

Related to the last question; Does it affect their status? (If a bird was high up the pecking order, does it remain so?)

At a guess, since it happens so much in some species, there hasn't been any strong evolutionary pressure to select againt it happening. Food is plentiful and sex drive is low, so status and pecking orders are less likely to be enforced, and temperatures are warm so baldness doesn't result in dangerous chilling.

It'd be interesting to see if moult baldness is less common in birds in colder regions (e.g. NW Scotland, arctic areas, high altitude cloud forest in the tropics, etc.).

Good questions. I wonder if it affects their flight at all? Even a very small effect--e.g. slightly reduced streamlining--might make them a bit more vulnerable to predation. And then there's the effects of the loss of insulation in the defeathered regions. Even if not important under normal conditions, severe heat spells or lengthy periods of wet & cold might be a different story.

Had this moulting mishap the other day, and found it quite amusing