The ‘Nordic’ effect

Arriving at Summer Leys’ Screen Hide on Sunday, 8th May, morning, Bob Bullock and I were confronted by this Jackdaw, clearly one of a pair, both of which were gathering food.

Jackdaw, Summer Leys, 8th May 2011 (Bob Bullock)

It clearly exhibits a silvery collar on the side of the neck – a variable feature associated with ‘Nordic’ Jackdaw, the nominate race, monedula, which breeds in southern Scandinavia and is a scarce, though regular, UK winter visitor. In all other respects it is, however, just a ‘Western’ Jackdaw, lacking the greyer underparts and contrasting black throat of ‘Nordic’ Jackdaw. Compare it with a typical ‘Nordic’ Jackdaw, photographed also

'Nordic' Jackdaw, Hayle, Cornwall, 12th April 2008 (Bob Bullock)

by Bob, at Hayle, Cornwall in April 2008. Our British and western European Jackdaws (spermologus) have been known to interbreed with ‘Nordic’ Jackdaws in eastern Europe so is it a ‘Western’ Jackdaw with Nordic genes or just a ‘Western’ Jackdaw with notable feather wear?