Alan Dalton post's birding diaries and original artwork from Sweden. Established in 2006, this now long running blog is now a complete overview of my birding experiences. As an artist I greatly enjoy sketching birds in the field and you will find a wide selection of that work here, from fieldwork to finished paintings. I am very passionate about my artwork and try to depict birds in their natural habitat, as I see them in the wild. My artwork is for sale and can be viewed at http://www.alandalton.net/
As regards to my photography, since 2008 I have used a Nikon D90 DSLR camera coupled with a Sigma 150-500mm OS lens for since March 2012 for bird photography, all previous images being digiscoped. Regarding sound recording, I have been usung a Telinga Stereo Dat Mic and parabol to record birds in the field, coupled to a Marrantz 661 digital recorder, a superb piece of kit. Interest in butterflies, dragonflies and damselflies has recently seen the accquisition of a Sigma 150mm macro lens. I hope you enjoy the blog and please feel free to leave comments or contact me at alandltn@gmail.com

Friday, September 04, 2009

Caspian Gull?; Skeppsbrön; 4th September 2009

Caspian Gull? Sub adult bird in 4th Calender plumage, Skeppsbrön. Note mirror on p10.


At rest on the water, note the length and shape of the bill, pale lemon iris, darkish mantle(was easily picked out amongst Herring Gulls on upperpart tone alone), smallish head and long slender appearance of the neck as well as the long primary projection. No obvious bulk with regard to the tertials, which sat rather level over the primaries with no signs of a "step" often seen in Herring Gull. The primaries were held raised off the water. All in all, the bird appeared elegant and attenuated, with a rather gentile expression facially.


In flight showing the underwing well. Obvious signs of moult on the inner primaries. The single mirror on the longest primary(P10?) well shown in this shot. Note also the dull flesh butterscotch legs shown by the bird here...

Taking off, another good view of the underwing features and limited views of the upperwing. Fresh inner primaries clearly visible in this photo, P1 through to P5 apper to to new, with p6 missing or in early stages of growth. p7 through to p12 are old and showing wear, they remain to be replaced, by which time p9 and p10 should both show a mirror at their respective tips...


The best shot I managed of the upperwing as the bird flew off after being spooked by an incoming boat. Limited dark upperwing coverts seen in this shot.

Caspian Gull location shot for all you swedish birders, never a bad idea to squeeze the national flag into the frame for reference...


A shot from the 5th September, the bird a litlle backlit on this occasion. Slighly closer views today all the same. The birds ID is now causing problems with me personally, as it doesn't quite seem to fit with a classic Caspian sub adult. Mantle tone the subject of some debate and was remarkably dependent on light conditions. In neutral light however the bird could appear alarmingly dark and more like a graellsi/hueglini Lesser Black Backed Gull...


Flight shot showing the underside of the wings. This photo clearly shows black markings on th primaries all the way back to P3, a little extensive for Caspian Gull?


The only shot I managed in close proximity to any other gull. Argentatus Herring Gull here for a size comparison. Throughout it's stay this bird was constantly the most distant gull on view, the bird would not mix closely with Argentatus of Fuscus and would not even compete for food in the form of bread and fish handouts which I tried to tempt the bird onto land with on several occasions.

Another backlit shot, this time of the bird in flight and showing the upperwing...



Hopefully a usefull shot of the upperwing. The only mirror is clearly visible on P10, though variable the bird should perhaps show a mirror on P9 if a Caspian Gull?


Caspian Gull is an extreme rarity here in Stockholm, so reports of a possible sub adult bird were enough to see me at the site at Skeppsbrön today. The bird duly obliged with its presence for an hour and I managed the above shots of the bird before it departed. Discussion of features under the images of a bird I reckon is a classic sub adult Caspian despite no previous experience with the species in the field. A cracking bird....
Edit; Following further views of this bird I now have doubts as to its identity as Caspian Gull and am starting to lean in the direction of a least some eastern Lesser Black Backed Gull genes, perhaps involving Barabensis or Heuglini races. Extremely difficult area this, little documentation on these birds at all, though hybrids occur, which only confuses matters further, Having no experience of these races and little enough of Caspian Gull I am rather out of my depth on this bird! Comments most welcome on this bird. Have also attached a number of decent photos of the bird taken by various birders during the birds stay...

Have trawled through Svalan's archives and dug up the following photos, which should prove useful, some rather good photos here. Unfortunatly cannot link to archived shots and have had to resort to photographing my computer monitor...




Photo above; Peeter Boldt Christmas

Photo above; Magnus Croon


Photo above; Mans Grundsten

Photo above; Hannu Koho

Photos Below; Mans Grundsten

No comments: