Regular readers might remember the ‘pigeon in the fireplace’ incident of March 2007, when a Wood pigeon Columba palumbus fell down my chimney during the small hours of the morning and had to be extricated at great personal cost to my epidermis. As I grabbed the pigeon, I was slightly dismayed that its entire rectricial array (viz, all of its tail feathers) came out in one clean, bloodless mass. The word on the street is that pigeons have very shallowly rooted rectrices and can effectively ‘drop’ the tail when grabbed by a predator, which is pretty neat I think you’ll agree.
So far as I can tell this is unique to pigeons. I’ve occasionally had to grab or restrain other birds by holding or pulling their rectrices (particularly budgies), and those feathers have always been well-rooted enough to prevent the escape of the bird. So it’s tempting to think that pigeons have ‘autotomic’ rectrices, convergently similar to the autotomic tails of some lizards, some mice, and some salamanders.
By bizarre and curious coincidence, I have recently been finding bits of evidence in the field that vindicate this idea (and by ‘finding bits of evidence in the field’ I mean ‘things I have stumbled upon while gallivanting about on various thrilling adventures’)…
Exhibit A is the dead Wood pigeon I encountered on the way to Southampton train station in August [shown above: that's the pose I found it in]. I initially walked past the bird and hurried on – after all, dead Wood pigeons aren’t quite enough to get me excited – but after a few minutes I knew I’d regret not photographing it, so I walked all the way back to where it was (partly this was to look at the ventral surfaces of the claws. I do a lot of that these days. You know why). To my mild surprise it was lacking rectrices entirely: it appears that the entire rectricial array had come cleanly away. I have no idea why it died, but it wasn’t far from the road and might have been hit by a vehicle (wood pigeons are good at this).
Exhibit B [shown here] was encountered today as Will and I walked home from school. A detached retricial array of a Wood pigeon (keys for scale). I cannot recall ever seeing a clump of retrices (of any bird) just lying on the pavement like this, and I infer that the entire tail array was dropped when, again, the bird underwent some sort of traumatic experience. If you’re wondering, yes these are definitely rectrices and not remiges based on their shape (squared-off ends) and distinctive three-shade banding.
If I didn’t already know that pigeons can do an emergency drop of their tail feathers, I doubt if I’ve had found these two discoveries interesting. But I do, so I did, and thought it worth telling you. Finally, back in May 2007 I wondered whether the pigeon I rescued would survive its ordeal. People told me that pigeons are tough and recover quickly from stress. Well, in the weeks that followed the rescue I saw what I assume was the same pigeon: a week after the rescue it had no rectrices. A few weeks later it had short ones, and so on and so forth. Of course, it might have been another pigeon that looked just like the one I rescued. There are a lot of them around and they’re not easy to tell apart. But never let the facts get in the way of a good story.
Hmm. I should write a regular column, like Carrie does in Sex and the City. Oh, maybe I already do.
Next… flightless pterosaurs!