It was with about 2000 Barnacle Geese but the terrain was favourable ... a flat grassy field with short turf where all the birds remained in view ...
... even when its head was down the dark plainish mantle made it relatively easy to pick out ... compared with feral Canada Goose ( Atlantic Canada Goose - Branta canadensis canadensis ) the pale bars on the mantle appeared finer and more crisp ... the bill was long but slightly less broad based than that of the nominate form ...
... it was considerably larger than the Barnacle Geese ...
After the flock was flushed the birds soon returned but the Todd's looked unsettled for a while ...
... the long thin neck was very apparent ...
The overall appearance of this bird seemed very much in line with individuals of this form B.c.interior that I had seen in the Pilling area of Lancashire on 2 Jan 2017 ...
... and in the Loaningfoot area of Dumfries & Galloway on 1 Oct 2013 ...
Looking back over the years, the early part of the 21st century saw considerable interest in Canada Goose forms and Todd's Canada Goose was discussed in two articles in Birding World in 2001 ...
Then in 2006 Harold Hanson published his monumental work that reflected 50 years of study ...
... this tome along with the one that followed a year later identified 6 species of Canada Goose with the canadensis group consisting of 78 sub-species and the hutchinsii group comprising 84 sub-species ... as the cover photo suggests, the book contains lots of pictures of dead geese and quite a lot of pictures of Canadian bogs - not the lightest of reads !
Today his work seems to be viewed as a step too far ...
The Helm guide of 2014 illustrates some forms including Todd's but the illustration left me feeling not much further forward ...
The excellent work of Sebastien Reeber 2015 gives much detail and highlights some of the ID difficulties particularly regarding the B.c.parvipes form ( confusingly called Lesser Canada Goose despite being part of the canadensis - Canada Goose species rather than the hutchinsii - Cackling Goose species which was formerly known as Lesser Canada Goose ). He describes parvipes as presenting on of the most difficult ID challenges and interestingly mentions intergradation between Todd's and this form.
The current page on the BBRC website is revealing ...
... so Reeber is the man and we should be thinking interior / parvipes
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