News leaked out yesterday evening of a
Caspian Gull
(kaspimåke) seen in Fredrikstad first on Sunday and then again
yesterday. I wasn’t sure as to whether to go for it today given that 1.) it
would mean twitching, 2.) an hour and a half drive, 3.) it was a gull and 4.)
it was dangerously close to The Great Big Dump, Øra. I awoke in a particularly positive
frame of mind though and thought what the heck. After getting the girls off to
school and kindergarten I headed south. I was not happy about the heavy rain which as usual didn’t correspond with what the weather forecast
from yr.no was telling me it should be but as I approached Fredrikstad it dried
up.
The bird had been seen in
Gamlebyen which is the old fortified town at Fredrikstad (one of precious few such
historical fortresses in Norway) and as I made my way through the cobbled
streets and parked by the river I saw there was another birder present. It was,
as I suspected, Eirik Grønningsæter who is attempting to break the Norwegian
year list record and had left Trondheim at 2am to get here (see his Big Year
blog on my blog list). We stood there, threw out bread, scanned the gulls,
chatted with a couple of other birders who popped in (including finder Asgeir
Larsen), stood there some more, scanned some more, chatted some more, threw
some more bread and three hours passed so quickly (not!). There were around 100
Herring Gulls in the area but there was little movement (there were most likely
another 1000 just down river at the Great Big Dump). It is amazing how little
gulls do during the course of the day and they were also not so interested in
the bread we threw out to them (although the bread old ladies had to
offer was scoffed up) and it is a wonder they get enough food. As you guess
though the bird in question didn’t turn up (although it is still in the areas a
unfortunately late report came in after dark that it had been seen at the Great
Big Dump).
If you pay enough attention to
large gulls you always find some odd ones and there were a couple that stood
out today. Norway has a handful of experienced and knowledgeable larophobes and
they are split into two “schools” (or they are by me at least): the
Eastern (ES) and Western Schools (WS). From what I can see they differ in their
teachings (and both schools have their disciples) by how they deal with non
classic specimens. For the ES it would appear that anything odd that can’t be placed
with safety in a bucket gets called a “presumed Herring Gull” with Herring Gull
being the default as it is the commonest large gull in Norway. The WS however
seems to prefer to use other labels for atypical birds and one particular type of
bird causes a lot of debate namely the “Bergenshybrid” which to the ES is a pale
extreme of Herring Gull whereas to the WS are hybrids (though not necessarily 1st
generation) between Herring and Glaucous Gulls. I have spoken (tediously and at
length) about these birds before and today there was a nice example of such a
bird (pictured below). Personally I’m not really sure how to classify these birds but tend
towards them being “just” pale Herring Gulls because they seem to be so regular
in the south whereas Glaucous remain a real rarity such that I can't understand where all these birds would originate if they were really hybrids.
On the other hand there are
a number of other birds that the ES label as “presumed Herring” which show great similarity to Caspian and
Yellow-legged Gulls and for which I believe it is wrong to not try to put
another label on as they push the boundaries of what a Herring Gull looks like
and is I think far too simplistic (to put in at another way there is no way
these birds would be accepted as vagrant Herring Gulls in Southern Europe). We
had one such gull today (pictured below) which for me had a lot of Caspian features although was far from
ticking all the boxes. However, it was also outside what I would expect a Herring Gull to look
like – it could well be a hybrid which
seem to be fairly regular in many mixed colonies in Poland and neighbouring
countries. This particular bird bore a colour ring allowing part of its life history to
be found at the few clicks of a mouse. This bird was ringed in Oslo on 4th
September 2012 as a Herring Gull in its 2nd cy (i.e was over a year old). On 4th
November it was 261 km away in Hirtshals in Denmark before returning north on 23rd
November to Moss (only 50km from Oslo) when it had the misfortune to be trapped
again. It was then seen in Fredrikstad on 31.12.2013 before my sighting today.
When you stand in the same place
for three hours you see or hear a few other birds and we heard a migrating
Skylark (sanglerke) which is my earliest Norwegian spring bird by a long way.
On my drive home I had three roadside Great Grey Shrikes which is back to the
expected level after a couple of quiet months and could also well be a result
of spring migration having already started for this species. A well timed stop
to expel excess liquid also revealed calling Bearded Tits at Sorgenfrigropa.
Extreme, pale Herring Gull aka "Bergenshybrid", alternatively Herring x Glaucous Gull Hybrid (2cy)
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note the pale wing with the outer primaries being the same brown colour as the darkest feathers elsewhere on the wing. |
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Here are three birds of the same age (2 cy) with the rear two being normal Herring Gulls. Note how on the paler bird the white edges to all the wing feathers are much broader creating a much paler impression |
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the pale bird is on the left. In addition note the broad pale edges to the primaries |
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Unidentified large gull with possible Caspian Gull genes (3cy)
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