BIRD GUIDING AROUND OSLO

Monday, 19 January 2015

Confusion

Constantly falling snow today caused a re-influx of hungry Blackbirds (svarttrost) into the garden and provided me with some interest today. In the half-light a good hour before dawn I could see from the kitchen window 7 individuals waiting in the snow but after I put some apples out there were never as many birds at one time however I did identify a minimum of 11 different individuals during the day including at least two new ones bringing the total now to at least 14 birds. Today there were a minimum of 8 males: 2 lacking black on the bill including the partially leucistic bird, 4 with some black and 2 2cy males plus at least three females including the tailless individual. The new birds were one of the 2cy males (I’ve only ever recorded one before) plus one of the females (two birds with black bills and tails today but of normal colouration).

This means in total I have identified a minimum of 14 Blackbirds in the last week: 2 adult males without black on the bill, 5 (presumed) adult males with varying amounts of black on an otherwise orange bill, 2 cy males and 5 females. It’s all getting a bit complicated now keeping track of them. I’ve tried googling to see what I can find out about the varying amounts of black on the bill and there seem to be three reasons: age, physical form (affecting carotenoid levels which causes the bill colour) plus also a reference on the BTO website to males acquiring a brighter bill when breeding. The 2cy males are quite easy to identify but the 5 other birds with varying amounts of black may be very advanced 2cy birds, 3cy birds, not in top form or quite simply in non-breeding plumage (it could be they are immigrants whereas the two with no black are local birds who still consider themselves to be in their breeding territories)


one of the two 2cy male Blackbirds. Yellow just at the tip. Whilst looking at this picture I now wonder if this is actually an old female that has an almost male like plumage - does a young male in January have paler edges to the breast and belly feathers? As I said this is starting to get confusing

the other 2cy male. Yellow at the base of the bill. The picture was taken through the window but this bird was without doubt a 2cy male.

I did manage a quick trip looking for gulls but could hardly anywhere almost as though there had been an exodus. At Kongshavn the Pintail (stjertand) which is usually at Østensjøvannet was seeking refuge as it often seems to do at the outset of snowy or very cold weather before it returns to Østensjøvannet again after a few days. Quite a few Goldeneye (kvinand) including an array of plumages which reminded me that my Blackbird problems are probably just down to individual variation.
 
Three 2cy (1st winter) male Goldeneyes all showing different development of the white spot on the face
an adult male on the left with the least developed of the three 2cy birds from the first photo


Three females. The bird closest uson the right is an adult female due to it bright golden eye and the yellow on the bill. The bird behind it has a dark eye and dark bill and is therefore a 2cy (1st winter). The bird on the left has a black bill but a pale eye so what age is it? I assume that is also a 2cy but one that has already developed a pale eye

The male Pintail
 

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