Friday, 11 January 2013

Ansers on a postcard

High tide at lunchtime, and quickly running out of residents and winter regulars to call on to boost my Inverkeithing list. Sparrowhawk should be along at some point but you can't rely on them. Pinkies, where are you? "Exotic" grebes and divers should become more likely but it's a bit early. I know they're out there but this far up the Forth you're hoping more than knowing. I thought that this could be the first site visit with no new birds recorded. Until, scanning the river (very high tide) for something out of the ordinary I did indeed find something you don't see every day in Inverkeithing ...



heavily lightened to reveal tonal contrast/coloration

heavily lightened to reveal tonal contrast/coloration

OK, so ....

(1) it's an Anser, from its bill alone we have either a Bean or Pink-footed Goose - dark with a small bright patch at the distal end (although not AT the end, obviously - I like the description "cigar band" from Duivendijk's "Advanced Bird ID Guide"). In the scope it was much easier to make out the patch, although who could call pink/orange at that distance at x25? Having said that, the contrast at that distance is more likely with orange than pink.

Next ...

(2) Of the three candidates we have a goose which has a fairly chunky and short neck and lacks the swan-like schnozzle of fabalis fabalis. It's not a Taiga Bean Goose. It's either a Tundra Bean Goose or a plain old PF Goose.

What else is there ...

(3) Even from this distance the the white stripe along the side is very contrasty. Furthermore it lacks the paleness and cold coloration of upperparts, and (not visible from the photos here) when I saw it flap once it revealed neither of the aforementioned features. Please note that the bottom two crops have been heavily lightened in an attempt to reveal coloration and cold/warm tones.

I think I'm inclined to say that this is a Tundra Bean Goose, Anser fabalis rossicus.

I would welcome dissenting voices and argumentation (although this is an overstatement, clearly)

7 comments:

  1. Hi Ali - yes, a true mystery photo; I'd be inclined to say it's a Pinkfoot, just gut feeling on the overall impression, and dark (lower) neck, though I could easily be mistaken given the range and light challenge; I also think that lack of pale or cold upperparts is not sufficient to rule out a Pink as they are so variable; finally I guess a transient tundra Bean is quite possible out on the sea but Pinkfoot would still be more likely with so many in the area - I recall one I saw on the sea amongst Eider way off Seton harbour on 2/1/10, clearly just briefly lost so pitched down for a rest.

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    1. Thanks for the input, especially on upperparts. This one aside I haven't seen a goose of any sort at Inverkeithing this year yet!

      It's interesting you should comment on dark lower neck as from what I remember from Duivendijk (which sadly I have left at work) this would count as another plus for Bean rather than PF

      I guess it will have to remain a mystery. Beans do pass through here in both directions but it's not exactly peak time

      Cheers

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  2. Poor photo below of a mixed group, 6 Beans out of 11 visible, not many are clear but the one furthest left is distinct in the pale neck sides, contra some of the Pinks which has solidly dark necks.

    http://3.bp.blogspot.com/-WeYACpCMQ_g/TzreAzHzR_I/AAAAAAAAB_Q/3PoMuDR_7e4/s1600/Beans%2B1.jpg

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    1. thanks - I looked at a few more shots with both species and it's hard for me to see much between them at the neck/head, especially taking into account posture and lighting. From the shadows it's clear that the bird on the left is in strong directional light. In some shots in the link below I can see a paler shape to the Bean's neck (faintly pintail-ish). I think the feature you're talking about is more clearly seen here:

      http://www.ribbletoamazon.com/2012/04/ribble-geese.html

      In this one
      http://www.flickr.com/photos/93372558@N00/6738839509/

      I can see where somebody might get the idea that Pinks have a dark head while in Beans the dark head "matches" the upper neck.

      I'm in danger of becoming interested in geese here. It's a concern! :)

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    2. Nice example there at top of ribble link, matches my impression of *some* from the field. If you want geese you are welcome to come over here, we're sinking in them - having over 1500 at last year's Bean Goose site ystdy (see blog) I started grilling them for Bean but it was a rather tedious and unrewarding job...

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  3. PS - the ribble link is useful in showing the slight difference in head profile, smooth line forehead to bill on many Bean but steeper forehead on Pink - from what I can make out your silhouette shot seems closer to the latter...

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    1. Tedious and unrewarding is exactly how I feel about grilling geese! (except maybe for a Red Breasted). I do like the impression of masses of them, and I like them individually. In terms of finding odd ones I like grilling geese marginally less than I like grilling gulls, which is not much :)

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