British Birding Association UK400 Club

Hi Graham

 

Autumn black-and-white flycatchers are problematic at the best of times and with the problems of intergrades and variability, individual identification in isolation can be particularly confusing. Browse for example Martin Cade's superb website http://www.portlandbirdobs.org.uk/aa_latestnews.htm and check out his latest entry. He has provided clear evidence here of the extreme variability in autumn Pied Flycatcher - by far the most likely bird to occur on the British East Coast and elsewhere. Pied Flycatchers regularly inhibit a suite of characters more often or not associated with White-collared or Semi-collared Flycatchers.

 

Krister Mild has been exhaustive in his studies of ficedula flycatchers and he summarised many years ago the following (1992-94), which can still be adhered to today

 

''The concealed pattern of the feathers of the nape, forehead and rump are IMPORTANT for SEPARATING AUTUMN birds IN-THE-HAND. ALL birds in non-breeding plumage (irrespective of their age or sex) can be identified on these characteristics. In the field, however, the patterns are concealed by overlying feathers. WHITE-COLLARED FLYCATCHER shows an anchor-shaped white pattern in the nape feathers which is LACKING in the other two species. The forehead feathers are similarly patterned, with WC Flycatcher showing an anchor-shaped or triangular white patch. The pattern of the rump feathers is also often diagnostic - WC and Semicollared naving an anchor-shaped white patch on the centre of the feathers. However, some Semicollared share a pattern like Pied, being just slightly paler along the central part of the feather shaft''

 

In my opinion, field identification of these flycatchers in autumn is rife with complication and from what I have seen of the current Fife and Norfolk individuals leaves me with no doubt that they both fall well within the variability of normal Pied Flycatcher. Furthermore, the real prospect of intergradation has to be considered, with (in some areas of Scandinavia) upwards of 30% hybridisation between Pied and White-collared on the breeding grounds. This could explain the extreme variability in the outer tail feathers in many Pied Flycatchers, a fair proportion of them having the white outer web extending right down to the tail tip (a Collared Flycatcher feature in reality)