Been interested in these for a while having found the first ‘Nordic Jackdaws’ in N. Ireland over a decade ago. Rewind? A brutally simpified over view:
3 Jackdaw subspecies in Europe:
ssp. spermologus. This is the one that lives and breeds in Britain. Found: western half of the Netherlands and Belgium, Britain, France, the Iberian peninsula and Italy.
ssp. monedula. (‘Nordic Jackdaw’), breeds in south-eastern Norway, southern Sweden and northern and eastern Denmark
ssp. soemmerringii. (‘Russian Jackdaw’) nearest breed S Finland but huge range extending east to Lake Baikal, Siberia, and north-western Mongolia, south to Turkey, and Israel and the Himalayas. P.S Jackies in Turkey look different to me. Maybe ‘pontocaspius‘. More on that again.
Matthew Silk sent these interesting images and a summary of his thoughts on the bird so far. It looks like an adult and think it seems a genuine candidate. Rudy Offereins who has championed the occurrence and ID of these things perhaps more than anyone notes that: more than 100 soemmerringii may winter annually in north-eastern France with 11 ringing recoveries in France of Jackdaws originally ringed from within soemmerringii breeding range. To me that makes ‘em likely to occur in England- and southern England at that.
RUSSIAN JACKDAW, Corvus monedula soemmerringii, in SUSSEX?
Martin kindly allowed me to post these photographs of a Jackdaw (Corvus monedula) showing characteristics of the subspecies C. m. soemmerringii that was present in a mid-Sussex garden in February 2007. Comments on its identification would be very welcome.
Clearly this individual belongs to one of the non-British races (monedula or soemmerringii). However, I have some experience with typical monedula jackdaws as they can be found in very small numbers most winters feeding with large corvid flocks in nearby fields, and this bird seemed different to those. The distinctive neck collar itself is within the range of monedula although it is extensive and very pale (despite the overcast/dull conditions these photographs were taken in) with a relatively distinct boundary, especially in the photos where the neck is less stretched. The collar also extended all of the way round the neck, although it was less distinct on the very back of the neck; a typical monedula should only show diffuse spots when viewed from directly behind. So whilst the neck collar indicates an eastern origin for this individual, collars looking like this do not rule out some more eastern monedula. The colour of the nape patch of itself is much more suggestive of soemmerringii, being pale (compare it to the local birds in one of the photographs) and having a distinct purple hue, in the field. Both of these features point strongly towards soemmerringii. The key feature shown by this bird which seems to suggest this bird is soemeringii rather than monedula is the colour of underparts (and the rest of the body). These were comparably dark to the local birds it was feeding with, whilst in monedula they typically do not contrast that greatly with the colour of the nape, and should appear much lighter than in spermologus. Another feature which was noted was a subtly different structure and jizz. Whilst the reading I’ve done does not suggest this to be a useful feature, this bird could almost be picked out on this alone when arriving in the garden to feed. I would be interested to know if measurements varied clinally along with plumage. Basically this bird seems to be a good candidate to be a “Russian Jackdaw” (ssp. soemeringii) but is it impossible to rule out intergrades with monedula or even perhaps an extreme monedula from the eastern part of that subspecies range? Whilst ssp. soemmerringii is not officially on the British list, it is considered a very rare winter visitor in the Netherlands so is likely to occur in Britain albeit not very often.
Some useful websites: