Sunday 15 September 2013

Not a Nordic Jackdaw?, Craigmillar, Edinburgh


I have seen this Jackdaw several times in and around Craigmillar over the last year or so. When I first sighted it in November 2012 it had a clear pale half-collar and it seemed a reasonable assumption to consider it to be a Nordic Jackdaw. Over the year I saw it again briefly in March but have been surprised to see it in both August and September in the same area. What is more, it is clearly part of a pair.


These first three photos were taken yesterday. I suppose the question is whether this bird is Nordic Jackdaw (monedula subspecies) that has pair-bonded with a local bird or whether it is a male Western Jackdaw (spermologus subspecies) towards the edge of its variation...


Here is the same bird taken with my phone cam out of the car in August - clear headlights...


To try to get an idea of how common Jackdaws with pale neck collars are among our breeding birds I tried to get some shots of representative individuals earlier in the year. Most birds observed showed no collar or if they did so it was very dependent on the angle of illumination. On the other hand a small number of birds seemed to show faint collars. For example, here is a shot of a group of Jackdaws and a Magpie at Duddingston in May. The left hand bird, in particular, showed a faint collar at all angles both in life and in photos. I think that I am now less confident rather than more confident of any of my previous records of the C. monedula monedula in and around Edinburgh, and that any identification of Nordic Jackdaw be resticted to individuals with very pronounced collars along with the other identification criteria (e.g. contrast between wing and body plumage giving Hooded Crow effect).



4 comments:

welchs said...

Hmmm, thought I spotted it again at the same spot last week; I last saw it there on 30 Januuary, but have not been past that often. You may recall I tried to turn "it", assuming it is one and the same, into a Nordic back in 2011:

http://sedgewarbler.blogspot.co.uk/2011/09/nordic.html

Morg said...

Stephen

Had forgotten that... but it is exactly the same location, and is almost certainly exactly the same bird.

So, it is a bird that is distinctive enough to get both of us to stop their vehicles and start digiscoping at a busy roadside... From that alone I think that we can conclude that it is not a typical spermologus. But given that it is resident in Edinburgh I think that we can also conclude that it is not a typical monedula either!

Is this a case for "showing some characteristics of"...

What do you think?

Geoff



welchs said...

Needs some more research I think - the Offereins article* has lots of useful insights, including for example that monedula plumage is variable and clinal; agreed this bird is a resident but does its residence here trump the fact that were it to be found in the range of monedula it would not be considered unusual? Unless there is any strong evidence to suggest that it would be very unlikely to be a displaced resident it seems to me we should not just dismiss the plumage - aberrant can't explain it either. So potentially a very interesting bird I think.

* http://calidris.home.xs4all.nl/monedula.htm

welchs said...

Another perspective (from Sweden!): http://sedgewarbler.blogspot.co.uk/2013/12/nordic-jackdaws-stockholm.html

Also check the nest-building Pembs bird on the link in that post - so it is certainly not unprecedented to find these as residents here, though I expect pretty rare! Very seldom taking car to work post-atlas, so not had chance to check on our little friend for a while...