This blog is about my birding exploits, which mainly take place in the Weymouth/Portland area, in Dorset. Will also include stuff from elsewhere, plus some other critters too. Hope you enjoy. All photographs are © Brett Spencer, unless indicated otherwise. The above image is of a Siberian Rubythroat, taken in Holland in 2016.

Friday, 30 October 2015

Identification Of Continental Coal Tit

After yesterdays fucking waffle, thought I'd revert back to interesting stuff. Chris Patrick took some photos of British Coal Tits today and in this post, thought it would be good to compare images of the 2 forms.

Note the differences in the extent of the black bib that can be used as a guide when getting onto a particular individual Coal Tit.


British.  © Chris Patrick/RNBWS

Continental. Black of bib extends onto upper breast and is crisp/well demarcated. Note also, the more extensive breast side blotching. The black of the bib can sometimes bleed into and include the breast side blotches as part of the bib.


British© Chris Patrick/RNBWS

Continental. Note how the black of the bib splays out at bottom and reaches the shoulder.


British. Even though the black bib splays out at bottom on this bird, black doesn't quite reach shoulders. Note, how in this photo it is difficult to interpret upperpart colouration, so important to view such colouration in the best light possible. © Chris Patrick/RNBWS

Continental. Black of bib splays out at bottom and black reaches shoulder. This individual doesn't have a particularly big bib and is possibly a female. Note mantle/scapular colouration though and tiny crest.


British© Chris Patrick/RNBWS

Continental.

Nape Patch differences.


British. Slightly narrower. Note the obvious olive toned mantle/scapulars, also shown in the wing and tail fringes. © Chris Patrick/RNBWS

Continental. Slightly wider. Note the blue grey mantle/scapulars, also shown in the wing and tail fringes.

Mantle/scapular colour and cheek patches.


British. Mantle/scapulars can have a grey look to it, but has an olive tone. Same colour in wing and tail fringes. Also, the lower rear of the cheek patches have a very very slight yellowish wash. The latter can only be detected at very close range in dull flat light and is probably lost through wear. © Chris Patrick/RNBWS


Continental. Mantle/scapulars steely blue grey, with no olive tone. Same colour in wing and tail fringes. Cheek patches purer white. 

Be aware how light can make judging mantle/scapular colour difficult at times, both in the field and especially from photographs. Differences in the Spring/Summer may be less obvious, but more research needed on this point.

Other more subtle features that may be seen are that Continentals look slightly bigger/bulkier and the steeper forehead, more raised crown, the latter producing a little crest when feathers raised, and more bull neck gives them a bigger headed look. Also, underparts may look less suffused with yellow buff on underparts, thus looking cleaner, but I suspect there is some overlap in this respect. 

Continental. The raised feathers on the crown shows a little crest. Note, how the blue grey can be seen on the outer fringes of the greater coverts on this bird.

Be aware how posture can affect some of the features noted here.

A word of caution on the bib size. I think that some, presumed male, British birds can overlap with, presumed female, Continental birds. Males, probably, generally have bigger bibs than females, but females can match males in bib size, so there is a degree of variation here. Like all these things, to come to a correct id, a combination of features must be used. Also helps if you're not fucking pink and green colour blind.

There is more to learn, for example, the possibility of vocal differences. Also, how numerous are Continental Coal Tits in Britain and their distribution? 

Has been great to learn more about these stunning little birds though.

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