Birds in the mist

Yesterday started very foggy and I was loathe to go out but eventually got off the sofa (I had fallen asleep watching the Japanese F1 GP) and headed out for what was only going to be a short trip. Maridalen was covered in fog and the fields still covered in snow although temperatures were +5C so it was melting quite quickly. I heard my first Green Sandpiper of the year, Oslo #118 and just about made out a Ring Ouzel plus some Woodcock tracks in the snow but quickly decided to head for Fornebu where I hoped I would be below the fog. I was but only just and there would be no chance of seeing viz mig (if there was any).

Friday’s Wheatear was still present so had survived the snow and at Storøykilen I picked out some Common Snipe with the thermal, had a couple of Green Sands fly over and noted there were quite a few thrushes flying around. At around 1130 the fog lifted a bit and as if by magic flocks of Pink-footed Geese appeared one after the other and then I could also see migrating Wood Pigeons, gulls and thrushes. I always feel torn in these circumstances and after half an hour I had to go up to Maridalen. This turned out to be the right move. The fog was just lifting and flocks of geese soon appeared but with there still being fog further north they ended up flying in all directions and many landed. My eBird checklist can be seen here but in summary I had a whopping 69 species with an adult White-tailed Eagle the highlight but also Curlew, Oslo #119, Grey Heron, Oslo #120 and a very early Wheatear, Oslo #122.

There were lots of thrushes and finches flying over and as the afternoon wore on and the sun came out and a fresh southerly wind started blowing there were suddenly Meadow Pipits and White Wagtails flying over. Skylarks were also back after a few days absence and in record numbers.

a flock of Pink-fooed Geese (kortnebbgås) coming into land at Maridalsvannet

Oslo's first Wheatear (steinskvett) of the year, a male in Maridalen

and Akershus's, a female which survived the snow

snipe thermalling season is upon us but so far only Common (enkeltbekkasin) to be found

an adult Peregine (vandrefalk) over Maridalen

and a distant adult White-tailed Eagle (havørn)

this Chiffchaff (gransanger) was feeding on the ground in a sign of how little food there is just now for them

Cormorants (storskarv) ssp carbo heading north over land, a sight that seems to be scarcer and scarcer every year whereas the sinensis are getting more and more numerous

Swan drama

Continued overnight frosts and cold northerly winds mean that birding remains very quiet. My first Chiffchaff of the year has been my only new migrant since my last update.

In Maridalen there is a lot of drama between the Whooper and Mute Swans. The Mute Swans returned a few days and begun nest building but the Whoopers have been making it very clear that their presence is not welcome. The Whooper have the upper hand and regularly give the Mutes a right proper beating. Both the Mute Swans are ringed and when they were with other Mutes this winter the male was apparently very aggressive towards the others. With the Whoopers though he seems to have met his match and then some. Time will tell how it goes but the Mutes put up with their beatings last year although that may well have contributed to their failed breeding although last year was their first attempt which will also have played a role.

I have not witnessed the big fights but others have and have documented it well on Facebook. When I was there today the Mute and Swans were about 100m apart and seemed calm. But when a flock of 6 Whoopers flew in and wanted to land then the Whooper pair started making a right old noise and flapping their winds which caused the flock to pull up and land elsewhere.

nest building Mute Swans (knoppsvane) in Maridalen

both are ringed. According to ringmerking.no the female is L071 but this birds size and behaviour suggests that must be wrong

the Whooper Swan (sangsvane) pair being dominant to warn off some of their kin who were about to land

and here are the other 6 Whoopers beating their retreat

my first Chiffchaff (gransanger) of the year

and my first migrating Cormorant flock of the year. These birds are of the North Atlantic carbo subspecies and are choosing to migrate overland to breeding areas on the coast of northern Norway. These migrating flocks are becoming far scarcer at the same time as the continental sinensis subspecies is becoming a common bird in Norway

most female Goldeneyes (kvinand) are paired off so the ones that aren't get a lot of attention

there are still flocks of Pink-footed Geese (kortnegggås) going north

and sometimes there are Beasts to see

There have been some birding highlights though which I will write more about later...

Fornebu again...

A probable female Black-eared Wheatear was seen at Fornebu yesterday evening so that was a good enough reason for me to get down there today. Unfortunately all the Wheatears I saw were bog standard Northern/Common but a pleasant time was had. Blue skies and almost no wind were not the best weather for finding something interesting and a female Redstart was the highlight on the passerine front. It took a while before I saw the tail on this bird as it skulked low down in a bush and I was thinking far rarer alternatives for a while. Alongside the Redstart was a Crested Tit in completely atypical habitat - sallow bushes in the middle of wasteland.
The nice weather did at least encourage the local raptors to show off with singles of Kestrel, Merlin, Sparrowhawk and Goshawk. The Kestrel was particularly showy and was mobbed by both the Merlin and Sparrowhawk in addition to local Crows and Jackdaws.
Lingering summer visitors were Yellow Wagtail, Chiffchaff, Blackcap and Swallow plus Dunnock.
I decided to pay attention to the Cormorants today as both subspecies (Carbo and Sinensis) have been reported and sure enough I found both to be present. The following photo has a Carbo (the northern cliff nesting subspecies) on the left and 2 Sinensis (the southern tree nesting subspecies) on the right.

How do you tell them apart? Well the differences are rather subtle. If you click on the picture you will see a large higher resolution version which will help. On the bird on the left notice how the angle of the gape (the innermost area of the yellow around the bill) is rather actute whereas on the righthand bird it is squared off. Additionally notice that the right hand bird has far more yellow around the bill (this is called the gular area) and less white surrounding the yellow than the left hand bird.

Definitely subtle differences but there are enough behaviourally differences for them to be classified as subspecies although here they seem to be quite happy hanging out together.