fredag 29. oktober 2010

4cy Caspian gull in Fredrikstad

The strong southerlies and horrendous weather the last couple of days tempted me to go and check the gulls today - it's almost three weeks since I last checked them out. Most rare gull observations up here have coincided with similar weather conditions, and Øra outside Fredrikstad is usually the place to go. Øra was a disappointment, though, with most gulls on unobservable roofs or far out in the estuary. On my way back, I checked some flooded fields and was, to my big surprise, awarded with a 4cy caspian gull! Caspian gulls older than 2cy are terribly rare in Norway, so this was a treat!

Note that the "head streaking" is confined to the lower neck and is very weak - like thin, weak, aquarelle streaks - as opposed to the heavy blotching in most herring gulls. In caspian gulls, this is also an indication that the bird is a 4cy. Fully adults usually have completely white heads.
When confronted with a typical, long billed individual like this, I couldn't stop the mind from wandering to Monthy Pythons legendary "Life of Brian" and the the "Big-nose" scene...

Adult, or near adult caspian gulls (or herrings/yellow legged gulls) should always walk around with a hanging wing like this individual. The hanging wing exposes the crucial P5 - normally hidden under the tertials. Here it is very obvious that P5 has a complete black band on this feather. Most herring gulls have only a black mark on the outer web on this feather, but complete black banded individuals are not very rare...

In flight, note the complete black band on P5, the white slivers on the upper hand, the long light tongues eating into the black on the underside of the outer primaries and that P10 has a subterminal band separating the white tip from the mirror - indicating that the bird is a 4cy.
From below, the black in the hand of an adult or near adult caspian gull builds a boomerang. It has less black than a herring gull, but is distributed on (on average) more primaries.

onsdag 22. september 2010

Scania, Sweden - Yellow Legged Gulls

Four merry lads spent a few days in Falsterbo, Scania, Sweden to watch the famous migration of raptors. Unfortunately, strong easterly winds made the raptors wait inland for more clement conditions, so we spent a couple of afternoons checking ports and harbours of Scania for other specialities, namely caspian- and yellow legged - gulls. Both species are regular in Scania between july and november. Caspian gulls can be quite numerous following easterly winds, while yellow legged occur in much smaller numbers. Here's a collection of photos of the five 1cy yellow legged gulls we managed to find. An entry with caspians to follow.

1cy YLG near Smygehuk 10.9. Sleeping. Even from behind it shows neat, compact build. Difficult to identify on these pictures, but other crucial features seen in the field.
Resting on the water. Lower right bird...

YLG 1cy Abbekås 10.9. Appropriately positioned! (Gäst means guest in swedish). A small and neat individual, so most probably a female. Not safely identifiable from these pictures, but it showed both typical tailband and inner primaries of the species.
High ISO pictures in diminishing light.
Sleeping on the left. Note the adult caspian gull on the right.

1cy Brantevik 11.9. A relatively small individual with a weak bill and unusually white underwing.

A few new LC and a growing inner GC.This bird was discovered in flight from a distance and was then thought to be a caspian because of the unusually white underwings.

1cy Simrishamn 11.9. Loooong distance shots, solely for documentation.

1cy Skillinge 11.9. Classical individual. Note the new inner GC and a few new LC. Several coverts dropped.
Typical dark wing. Note apical spots on inner primaries.
Unusually heavily marked inner tail and uppertail coverts. So it wasn't that classical anyway...
Here with an adult caspian..

torsdag 26. august 2010

"JOHN" - The first ringed Yellow-legged gull in Norway

On the 12th of august, a 1cy yellow-legged gull was discovered at "brennevinsmyra", the city dump of Mandal. It was found by the gull-ringing enthusiasts Morten Helberg and Finn Jørgensen. Two days later, the bird was relocated, caught and ringed by Morten Helberg and Inge Flesjå. It was awarded with a black colour ring with white code "JOHN".

It was a rather small, short legged individual, suspected to be a female when first observed, and measurements later confirmed this. This constitutes the first ringed YLG in Norway and it feels absolutely right that the event happened in Mandal. It is a tiny city, even by norwegian standards, but is inhabited by more gull-enthusiasts than the rest of the country combined...

Most photos Inge Flesjå.

A short-legged individual, but apart from that it exhibits typical 1cy michahellis features: light head with dark eyemask, all-dark blunt tipped bill, advanced scapular moult (compared to the local herrings that is, many YLG are far more advanced than this), tertials with white markings restricted to the tips/edges of the outer 2/3 of the feathers, mostly white vent/belly, bubble-gum pink legs and a "half dark - half light" greater covert bar. Note also that the tail-tip aligns with P6. Typically it aligns with P7 on herring gulls. In this posture it doesn't show the typical squarish head shape, but the sudden bulge beetween the bill and eye is most typical. Note also the rather athletic shape with compact body and protruding breast, but this feature is much more pronounced in males.

Underwing a bit darker than the average YLG. They often show more whitish markings, especially on central underwing.

Typical YLG wing in the dark end of the spectrum. Greater covert bar becoming progressively darker towards the carpal joint and a very limited primary window with light confined to inner webs of the inner primaries.

Note again the bulge in front of the eye and the blunt-tipped bill.

Contrasting black tail-bar because of almost all white vent and undertail coverts.

Very typical from above with dark outer/light inner webs to inner primaries, greater covert bar, contrasting black tail-bar and pronounced dark facial mask on otherwise whitish head. Even in flight the head shape is discernible.

Note tertil pattern, greater covert bar and white rump/upper tail with a single row of black markings on upper tail feathers.

Very contrasting tail bar because of otherwise almost pure white tail. Note also light inner webs of primaries.

Morten Helberg in action, ringing "JOHN". Morten has done quite a lot of research on norwegian populations of lesser black-backed gulls, giving headaches to everyone who thought they knew the species and its variation.

Morten showing the upper wing of "JOHN".

"The gull wizard" himself - Inge Flesjå, having the time of his life, being bit by a "mich". This was apparently the first time these guys had photographed one another! It took a michahellis and quite a few years..! Inge is, of course, the man behind norways first michahellis and cachinnans. Nobody is even close to his track record in Norway, finding rare gulls. Apart from that he has found numerous other rarities, and I bet very few in europe (anyone?) has found both subspecies of Turdus naumanni on western european soil? Well, Inge has...

Written by SEN

tirsdag 15. juni 2010

2cy Lesser Black-Backed Gulls again...

I'm still fascinated by the variability of 2cy LBBGs. At times it is difficult to believe that two individuals standing side by side belong to the same species...Here are pictures of 5 different birds, all from Fredrikstad, Østfold the first week of june. See also an earlier entry here:

A small and delicately built individual and most likely a female. Mostly (2. gen) ashy grey upperparts with a broad, diffuse shaft streak on mantle/scaps and anchor-patterns on the coverts. Juvenile flightfeathers and rectrices. Very likely intermedius from the local population(?).

Individual #2
A completely different individual with pale grey mantle and scapulars with distinct anchors - a feather-pattern reflected in the renewed coverts.
Contrasting in flight, very reminiscent of an autumn/early winter michahellis. In this individual the head/bill - shape adds to this similarity. Note also the rather conspicuous window on the inner primaries, a feature many spring 2cy LBBG's show up here, probably due to wear.

3 central pairs of rectrices renewed but juvenile primaries (P1 dropped) and secondaries.

Primary window again..To me, this was a confusing individual, but I have later received feed-back from Ruud Altenburg, Holland, stating that this is a fairly common type of 2cy LBBG. There you go..

Individual #3
A big, heavy-billed LBBG, most probably a male. It was very aggressive and didn't hesitate to attack GBBGs and fight them for food. This bird had mostly slaty grey mantle, scapulars and new coverts (best seen on the flight shots) and is much purer white on the head and underparts than #1 and #2. The underwing is also predominantly white where the preceding birds where heavily marked.

P1 growing, P2 dropped, rest of flight feathers juvenile. Central pair of rectrices renewed.

Individual #4
A huge and mean-looking individual with pale, slate grey new mantle, scapulars and coverts. Very similar to #3 with which it was seen side by side, but bigger and with paler grey plumage.
P1 dropped, rest of flight feathers juvenile (and note the inner primary window on both #3 and this bird). Central pair of rectrices renewed.

Even whiter underwings than #3.

Individual #5

A small individual that unfortunately was only observed and photographed (well, sort of..) from a very long distance. The photos don't offer much, but it is visible that the bird had a full set of new primaries and secondaries. The entire tail was also renewed. This is of course indicative of fuscus, but heaven knows with these birds...