The sightings and occasional thoughts of an English birder in Oslo
Friday, 30 August 2024
Return of the Taiga Beans
This spring there were still 2 of the “Scottish” Taiga Bean
Geese with functioning GPS collars one of which uses the Norwegian migration
route and the other the Swedish route. During the summer a lack of plots led me
to think the collars had stopped working but 05, the Norwegian bird, has come
online again so the birds were maybe just in wilderness areas without mobile coverage.
05 who is a female and paired with a tagged bird V8 (they
both were tagged on 5 Nov 2022) left her moulting grounds, close to the
breeding areas in Sweden, before dawn on 24 August and arrived at a favoured
field 4 and a half hours later. This favoured autumn field is one of the very first
to be harvested and I think this is the reason it is chosen initially. There
was a bit of a lag in the plots but once I was aware of her arrival on Monday I endeavoured to go find them on Wednesday. Sure enough they were on
the same field and it was the only one in the area to have been harvested. It
is right by a road and passing cars and lorries cause them no alarm but as soon
as I stopped my car all their heads went up. They soon resumed feeding though
but I chose not to leave the car which did rather reduce by viewing options.
Every time I counted the flock (both in the field and from
pictures) I came up with a different number but have settled on 93 being the
most accurate. I could only see three collars: 05, V8 and 27. 27 is a no longer
functioning GPS collar which was ringed on 24 October 2019.
The number of collared birds is declining for every season
(some lose their collars but still have leg rings which can only be seen in
very favourable conditions which I did not have today as the stubble was too
high and I did not have birds in flight at close range when photos can reveal
the rings) but we are certainly losing a lot of birds to old age, predation and
quite possibly hunting. This is also supported by a general decline in the
number of birds using the area in both spring and autumn.
They can live quite a long time with one of the ringed birds,
6U, having been ringed on 12 Oct 2011 (when the first birds were ringed) and last seen (by me) on 30 March 2023
when it was at least 12 years old (I don’t know if it was a juv or adult when
ringed). The flock size is declining year on year and although some birds maybe
are choosing different routes there seems to be a real lack of reproductive
success.
I usually find it difficult to pick out the young birds but
the conditions yesterday were perfect for doing so. Unfortunately I forgot to
do so whilst watching them but luckily took enough photos that I have been able
to go through most of the flock and looks for juvs. What I found is worrying. The tagged
bird 27 and his mate had 3 young but other that that I have only managed with
certainty to find two single juveniles in the flock.
To the right is 27 whose watchful behaviour shows him to be a gander. To his right is his mate and then three juveniles
the same bird with another adult to the left
a single juvenile
and another juvenile
V8 and his mate with the GPS collar 05. These two can also be seen in the video (below) including how O5's collar moves up and down her neck which looks as though it must be quite uncomfortable
V8 telling someone off
the flock moved a 100 metres or so at one stage
here I have enlarged 27 who leg ring with the code Y7 can also be made out
the whole flock
my viewing position off the road
here I have briefly stopped the car on the road and the flock are ca. 100m away
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