Friday 28 February 2014

Ross's Goose x Barnacle Goose

Ross's Goose x Barnacle Goose hybrid, Snettisham (Norfolk, UK), 17th March 2009 - copyright Dave Appleton
(photo ID: 0162)


Next to Greylag Goose x Canada Goose, this seems to be the most frequently-occurring goose hybrid in Norfolk at the moment, although I am not sure why.  Several reports of Snow Geese have turned out to be these birds.  This first two shown here were alongside 2 Ross's Geese among a flock of feral Barnacle Geese.


Ross's Goose x Barnacle Goose hybrid (same bird as in photo ID 0162 above), Snettisham (Norfolk, UK), 17th March 2009 - copyright Dave Appleton
(photo IDs: 0163-0164)




Ross's Goose x Barnacle Goose hybrid (the second individual), Snettisham (Norfolk, UK), 17th March 2009 - copyright Dave Appleton
(photo IDs: 0165-0167)


The next individual also normally associated mainly with a small feral flock containing both Barnacle Geese and Ross's Geese, although when I first saw it it was in a flock of Canada Geese.



Ross's Goose x Barnacle Goose hybrid (with Canada Geese), Salthouse (Norfolk, UK), 4th December 2010 - copyright Dave Appleton
(photo IDs: 0168-0170)





Ross's Goose x Barnacle Goose hybrid (with Barnacle Geese and Ross's Goose - same hybrid as at Salthouse in photo IDs 0168-0170 above), Cley (Norfolk, UK), 3rd January 2011 - copyright Dave Appleton
(photo IDs: 0171-0174)


This bird was also reported at nearby Bayfield Lake, which is the same location as where the next photos were taken 3 years later.  However the two birds photographed this time were much closer to Barnacle Goose in appearance than this hybrid usually appears, prompting questions over whether they could be backcrossed.  The working assumption is that this intra-generic hybrid should be infertile, in which case they cannot be backcrossed, so either it's just within variation for the hybrid or else the assumption is incorrect.







Ross's Goose x Barnacle Goose hybrid (with Barnacle Geese), Bayfield Lake (Norfolk, UK), 25th January 2014 - copyright Dave Appleton
(photo IDs: 1513-1519)


The following two birds were photographed in a wildfowl collection but according to the owner they did not belong there and arrived on their own accord.  In most respects they resemble other examples of this hybrid but the neck appears a bit long in some photos.  The possibility that Canada or Cackling Goose might be a parent instead of Barnacle Goose is perhaps not completely eliminated, but I would expect it to look browner if that were the case.  Note how one of the birds has a much brighter bill than the other.







presumed Ross's Goose x Barnacle Goose hybrids (first 4 photos are one bird, next 3 are the other), Blakeney (Norfolk, UK), 12th February 2011 - copyright Dave Appleton
(photo IDs: 0177-0183)


Although never far away from feral Barnacle Geese the next bird is often mingling with wild Pink-footed Geese, and in at least winters it has been reported erroneously to the rare bird news services as a blue morph Lesser Snow Goose.



Ross's Goose x Barnacle Goose hybrid, Burnham Overy (Norfolk, UK), 12th January 2013 - copyright Dave Appleton
(photo IDs: 0186-0189)


The next bird appeared among wild Pink-footed Geese.  Unfortunately it was very distant so not seen well, and photographed even less well.  Even in poor views it was clearly different from the widely-observed hybrid that had been wintering with Pink-footed Geese in Norfolk during previous winters (see here), being much smaller, darker backed, having more white on the neck and a duller bill.  It seems to fit Ross's x Barnacle fairly well, but had more white in the tail than this hybrid usually shows.


probable Ross's Goose x Barnacle Goose hybrid, between Anmer and Shernborne (Norfolk, UK), 9th January 2011 - copyright Dave Appleton
(photo IDs: 0175-0176)


Another bird that turned up among feral geese in Norfolk - perhaps one of the same birds as seen elsewhere?


Ross's Goose x Barnacle Goose hybrid, Raynham Lake (Norfolk, UK), 2nd April 2012 - copyright Dave Appleton
(photo IDs: 0190-0191)


The next bird is intriguing as it differs from most examples I've seen of this hybrid in having much more white in the plumage, most obviously on the upperparts.  The white plumage and white edges to the tertials suggest Snow or Ross's Goose parentage with the small size and the structure fitting the latter best (although we are not agreed on that - one view is that the size/shape of the bill and shape of feathering at the base is subtly different from Ross's x Barnacle and more like what we might expect on Snow x Barnacle).  It does not resemble Ross's Goose x Canada/Cackling Goose hybrids and the blue-grey tones to the wing feathers seem to me to suggest Barnacle Goose.  As always, comments are welcome so if anyone has any other thoughts please get in touch.  Other photos of this bird appear on the Devon Birds website (those on the entry for 18th February 2015 are perhaps the best).




probable Ross's Goose x Barnacle Goose hybrid (with Canada Geese), Wrafton (Devon, UK), 5th April 2016 - copyright Chris Bollen
(photo IDs: 2801-2804)


This bird remained asleep for the whole duration of my visit, but as I knew there was a Ross's x Barnacle Goose here I assumed it was the same bird.


captive? Ross's Goose x Barnacle Goose hybrid, Cleethorpes Boating Lake (Lincolnshire, UK), 7th April 2012 - copyright Dave Appleton
(photo IDs: 0184-0185)


I'm not sure if this one was the same bird too - if so it looks quite different from how I'd imagined mine would have done had it woken up.  In fact it recalls the Devon bird above in the extent of white in the plumage.  The grey areas seem unsually dark too.  Howver it is hard to see what else it could be.


captive? Ross's Goose x Barnacle Goose hybrid, Cleethorpes (Lincolnshire, UK), 3rd February 2016 - copyright Philip Ridsdale
(photo IDs: 3102-3103)


(See also: Snow Goose x Barnacle Goose, Ross's Goose x Canada Goose, Ross's Goose x Cackling Goose)



Ross's Goose Anser rossii or Chen rossii
Barnacle Goose Branta leucopsis 

Ross's Goose x Cackling Goose

Ross's Goose x Cackling Goose hybrid, Longmont (Colorado, USA), 16th November 2013 - copyright Cathy Sheeter
(photo ID: 1848)


This bird was smaller than a Snow Goose x Cackling Goose hybrid Cathy photographed at the same site a couple of days earlier, and other differences confirmed it was indeed a different individual.


Ross's Goose x Cackling Goose hybrid (same bird as in photo ID 1848 above), Longmont (Colorado, USA), 16th November 2013 - copyright Cathy Sheeter
(photo IDs: 1846-1847)


Steve informs us that the next bird was clearly the smallest goose among several hundred Canada Geese (both parvipes and moffitti) and Cackling Geese (mainly hutchinsii but also a couple of taverneri).  The tiny size shows up in the next photo as does the very delicate head and bill.  Steve believes that what looks like a hint of a grin patch is mostly due to the extensive dark on the lower mandible.




Ross's Goose x Cackling Goose hybrid, Broomfield (Colorado, USA), 26th February 2012 - copyright Steve Mlodinow
(photo IDs: 1310-1313)


The next one is also tiny, with a very small bill lacking any grin patch.



Ross's Goose x Cackling Goose hybrid, Longmont, Boulder County (Colorado, USA), 17th November 2013 - copyright Steve Mlodinow
(photo IDs: 1133-1135)


In life the next bird appeared slightly smaller than the Cackling Geese it accompanied and its bill was even shorter than the Cackling Geese.  Steve considers that the Cackling Geese are probably Richardson's hutchinsii but isn't ruling out Taverner's taverneri.



Ross's Goose x Cackling Goose hybrid (with Cackling Geese), Stewart's Pond, Weld County (Colorado, USA), 16th March 2015 - copyright Steve Mlodinow
(photo IDs: 2139-2141)


Steve says that the next bird, smaller than nearby Cacklers with a tiny bill, is pretty clearly a Ross's x Cackling Goose:

Ross's Goose x Cackling Goose hybrid (with Cackling Geese), Lower Latham, Weld County (Colorado, USA), 22nd February 2016 - copyright Steve Mlodinow
(photo ID: 2729)


Steve describes these as "especially cute, with round heads and dinky bills."  Yes, I suppose they are cute...


Ross's Goose x Cackling Goose hybrid (with Cackling Geese), Frederick, Weld County (Colorado, USA), 29th November 2016 - copyright Steve Mlodinow
(photo IDs: 2881-2882)


(See alsoSnow Goose x Cackling Goose, Snow Goose x Barnacle Goose, Ross's Goose x Canada GooseRoss's Goose x Barnacle Goose



Ross's Goose Anser rossii or Chen rossii
Cackling Goose Branta hutchinsii