Category Archives: 09) Skuas, Gulls, Terns

Great Skuas summering off Flamborough

and them Pomarines

Martin Garner

Great Skua 28th June M Garner f (1 of 1)

Skua watching has been unusually good off Flamborough this June. However it’s not of the expected species. Up to 7 Pomarine Skuas and several Great Skuas seem to be summering in Bridlington Bay. Most individuals, especially the Pomarines appear to be immature birds as might be expected.

This Great Skua came particularly close this morning. The dark ‘hooded’ head and pale base to the upper mandibles indicate this should be an immature bird. I might take a stab at it being a 2nd summer. I haven’t looked into any literature but it would be interesting to see if the details in the photos can lead to a more definitive ageing.

Have a look:

Great Skua 28th June M Garner d (1 of 1)Great Skua 28th June M Garner a (1 of 1)Great Skua 28th June M Garner e (1 of 1)Great Skua 28th June M Garner g (1 of 1)

Ivory Gull in Varanger

I Never Dreamed…

Ooo… just missed turing up for the 2015 Gullfest. Still must a bit heart soul and body warming encounter for Simon Colenutt and Trevor Codlin in Vardo harbour  who found this adult Ivory Gull at the start of this week (22nd March 2015). Read  Biotope’s account of the Ivory Gull at Vardo,

Simon writes: ‘What a cracking bird! I never dreamed of finding Ivory Gull!”

Read more of Simon and Trevor’s visit at ‘The Deskboundbirder’

Check out that head shot!

Ivory oneb (1 of 1)Ivory one (1 of 1)Ivory onec (1 of 1)Ivory onea (1 of 1)


Juvenile/ 2cy Thayer’s Gull in Iceland

Helgavik Harbour, South West Iceland. 15th-16th March 2015

Following this 2nd winter trickier bird, Derek Charles and Edward Rickson picked up this more straightforward 2cy (juvenile/ first winter) Thayer’s from SW Iceland last Sunday and Monday (15-16th March).  It’ s a bit mealier below and paler in scapulars above than some but certainly  fits the Thayer’s ‘look’ overall. Derek also picked out a Brünnich’s Guillemot which proved popular with Icelandic birders. Nice!

One interesting point, Derek noted was that all first winter Iceland and Kumlien’s were extremely worn compared with this Thayer’s, furthermore making many Kumlien’s considerably more difficult to distinguish. All among the glorious swarm of March Icelandic Gull acton!

2cy Thayer’s Gull. Helgavik Harbour, March 2015. All photos Derek Charles:

tfive (1 of 1)

tfour (1 of 1) tone (1 of 1) tthree (1 of 1) ttwo (1 of 1)

Thayer’s Gull in Iceland?

Challenging 2nd winter plumage

Martin Garner and David Walker

First off checkout this amazing photo of the awesome gull swarm at Olafsvik, Iceland last year. From Dungeness Bird Obs warden Dave Walker- man you wanna go there!

Martin Casemore Plodding Birder and David clocked the darker bird looking a candidate 2nd winter’s Thayer’s a few days ago at Grundarfjordur, Iceland. It’s a bit of a scary bird, so a few photos and some comment. Lot more pictures of the bird on the Dungeness Bird Obs website.

gull flock (1 of 1)


 Gull sp , Grundarfjordur, Iceland, March, 2015

t12 (1 of 1)t125 (1 of 1)t123 (1 of 1)t17 (1 of 1)

 From MG:

“From the first photos it is pretty Thayer’s like. Indeed I suppose it may well be the progeny of 2 adult Thayer’s. However for ID purposes of vagrants I would not peg it as identifiable/ acceptable if it was say in the UK. There are a number of features that put it into the uncertain/ what is going on? box. On the broad front I wonder if there is some pioneer zone where there is some gene mixing- say NW Greenland and these scary ones show up from.

Specifically- and your photos show this much better- it is very mealy dark/light patterning in greater coverts- most often thayeri is quiet plain, the outer primaries have less dark than ideal- best if it crosses to the inner web- and the pattern starts going weak from p6, also not so good. There is a pale spot even if not a proper mirror on p10 and the little subterminal string of pale spots on p8 ish and inwards is definitely odd and maybe better for kumlieni I think.

So that combined set of slight oddments are a least at ‘edge’ of acceptable 2nd winter Thayer’s would make me say it’s best left as Thayer’s -like but uncertain ID. It’s not dissimilar to some we showcased here  and those features are hashed out further here. I have seen quite a few 2nd winter Thayer’s and most look more straightforward- which is of course you want when claiming vagrants! Always learning…”

argentatus Herring Gull wing tips and travels

Remarkable Movements

Martin Garner

It’s what they do, where they go, how far they travel,  the ‘gull narrative’ that adds to the wonder. While Gullfest 2015 is cooking in Vardø and folk visit the mighty Hornøya  Island. Here’s one of those stories.


JX347:  Hornøya to South Yorkshire and back again and back again

JX347 having been rung on Hornøya has wintered in South Yorkshire- two years running! As a first winter bird and as a second winter bird- and been well photographed. The variety in young northern argentatus Herring Gull is quiet considerable. This one is not an easy ‘pick-out’ on plumage. And what route did it take to reach the UK? Over the arctic top like this Great Black-backed Gull or through the Baltic? Both are possibilities. Have  look:

First Winter plumage 

(poached from excellent  Barnsley Bird Blog - photo by Steve Denny)


Second Winter plumage

In Sheffield last month- (photo by Andy Deighton)

shefield 2


Thanks to Andy Deighton and Morton Helberg for following:

CR-Code Black ring with white code: JX347 LBM;RBNW(JX347)
Ringing Centre Stavanger Museum (Norway) Ring number 4193850
Species Herring Gull  Larus argentatus
Sex Unknown Age Pullus

Date Place Coordinates Observers Days/km/°
29.06 2013 Hornoya, Vardo, Finnmark, Norway 70°23’16″N 031°09’21″E Lyng, Torben -
26.02 2014 Anglers Country Park, Wintersett, West Yorks, Great Britain 53°38’19″N 001°25’56″W Leeman, Brian 242/2464/237
02.03 2014 Wintersett Reservoir , West Yorks, Great Britain 53°37’42″N 001°25’57″W Denny, Steven 246/2465/237
02.03 2014 Wintersett Reservoirs, Great Britain, Great Britain 58°38’00″N 001°26’00″W Denny, Steven 246/1994/245
11.02 2015 Warren Street, Sheffield, South Yorks, Great Britain 53°23’21″N 001°26’41″W Deighton, Andy 592/2489/236

 to compare- a similar 1st winter was photographed at Vardø April 2012:

argy first winter  vardo (1 of 1)

Adult wing tips

Since the early 1980’s these have fascinated me (especially when the local county refused to accept the records!). The most interesting have usually been the ones with reduced black and more white in the wing tips. Some sporting the ‘thayer’ pattern on the outermost primary P10 and even on the penultimate long primary p9. What’s the thayeri pattern? As on an adult Thayer’s Gull, the pale/ white wedge on the inner primary runs right through to th white ‘mirrors’ near the tip and NO black cuts across the feather- as on the typical pattern of most dark winged Large Gulls.

Here is the thayeri pattern from  Banks from 1917- “The Status of Larus thayeri. Thayer’s Gull”

The pattern on the right show the uninterrupted white right through to the wing tip.


Thayeri wing tip Banks


So here’s some argentatus  with the thayeri pattern

from Gullfest 2013 at Vardø

ad argy white (1 of 1) argentataus adddb (1 of 1) argentataus adddbm (1 of 1) argentatus 1 (1 of 1) argentatus 45a (1 of 1)argentatus adult wing 13 (1 of 1)argentatus adult wing 4 (1 of 1)THAYERI ARGY3 (1 of 1)THAYERI ARGY4 (1 of 1)

not visible this just has thayeri pattern on p9argy wing not used

This one has nice long tongue but no thayeri

THAYERI ARGY6 (1 of 1)

Darker-winged adults

we also found darker winger birds- some with 6 black marked primaries which were intriguing. one of these had been rung further south in the Baltic.

argentatus adult wing 1 (1 of 1) argentatus adult wing 2 (1 of 1) argentatus adult wing 10 (1 of 1) argentatus adult wing 11 (1 of 1)


Ringed in Poland 

This next bird was trapped at Vardø already sported ring from Poland. Pink-legged and dark backed it was the darkest winged bird we trapped. 6 black marked primaries including dark band across p5.

argentatus adult wing 12 (1 of 1)

Gdansk ring b (1 of 1) Gdansk ring c (1 of 1)


another darker winged bird

back to those beautiful pale wing tip patternsargentatus c (1 of 1) argentatus extreme a (1 of 1) argy 3 (1 of 1)

How cold? Waiting to explore gulls and ducks…blizz (1 of 1)


Colourful ducks

with rubbery looking fish lips and amazing plumage tones- in both males and femalesstelers onee (1 of 1) fem steller's e (1 of 1)

and King DucksKing eiders (1 of 1)

and pretty smaller gulls

whose wing tip patterns we are exploring…

Kittiwake ne (1 of 1)

Glaucous Gull fest

Malted Milk

at the Northernmost Birding Festival… in the WORLD!

Gullfest 2015 poster A2 - Vardø aerial biotope

Here’s few shots of young Glaucous Gulls. Mostly taken in the harbour at Vardø, Varanger where the Gullfest 2015 is happening as I write. I can’t  be with the guys this time so I’ve dug out some old, unused and some intriguing pics from previous Gullfests.

Also I will throw in some scary unidentifieds and a little colour for those less gull- inclined :)

These are mostly juveniles or if in moulting, technically  first winters in March (2cy)

1st w Ggull (1 of 1) 1st w Glaucous (1 of 1) 1st w Glaucous b (1 of 1) 1st w Glaucous G n (1 of 1) 2cy Glaucous  (1 of 1)2cy pretty glauc (1 of 1) pale billed Glaucous (1 of 1)glaucous 1 (1 of 1)glaucous 2 (1 of 1) 2cy g ullll m (1 of 1)2cy glgg (1 of 1)

a couple of second winters (3cy) …2nd w Glauc (1 of 1) 2nd w Glaucous (1 of 1)


le flocksGlaucous g (1 of 1)


and a mystery gull (whatdoyathink?)

Viking 1 (1 of 1)Viking 2 (1 of 1)Viking n Glauc (1 of 1)

2cy gull interetsingd (1 of 1) 2cy gull interetsingh (1 of 1)

and a red thing from nearby :)

When you see Pine Grosbeaks flying around chasing each other through taiga zone trees and canopy,  they make wonderfully fluty calls


and a young red thing who will one day, look like the fella above (photo:Tony Davison)

Pine Grosbeak b 20.3.13


Calls of Thayer’s, Kumlien’s and Iceland Gulls

Peter Adriaens

(MG) A reblog from last January and one of my favourites. With Iceland, Kumlien’s and Thayer’s Gulls  around- is anyone recording calls? Come on chapesses and chaps-  a wonderful frontier...

Interminable debates have surrounded the identity and taxonomy of Thayer’s, Kumlien’s and Iceland Gulls of Arctic Canada. Until now, most of these have focused on plumage similarities and differences. Having obtained recordings of Kumlien’s Gulls in Newfoundland in early 2013, comparison could then be made between all 3 taxa. The long call of gulls is effectively their ‘song’. When the flight calls and especially long calls of the 3 are compared, the results are unexpected and surprising…

While our knowledge of birds in general has increased exponentially over the last few decades, it seems that some gull taxa have managed to remain a mystery. This is particularly true for the “Iceland Gull complex”. The taxonomic position of Thayer’s Gull, Kumlien’s Gull and Iceland Gull is a much discussed topic, but for the last 15 years or so, the debate seems to have been going in circles rather than forward. It may even be going backward: indeed, Snell (2002) in ‘Birds of North America online’ treats the three taxa as just one, monotypic species, Larus glaucoides. Thus, we are led to believe that gulls with white wing tips (glaucoides) living in Greenland are the same taxon as gulls with black wing tips (thayeri) living in western North America, 2,000 to 5,000 km further away. Convenient perhaps, but a bit despondent surely?

The debate is characterised by many unanswered questions and a lot of speculation. To add something more informative, I would like to draw attention to the calls of these taxa. For display, large gulls have a “long call” that is unique to each taxon. It is effectively the song of a gull, and consists of three separate stages, the third one being a long, loud series of fairly short, staccato notes. One thing that the three “Iceland Gull taxa” have in common, is that the staccato notes of the long call are delivered more slowly than in other large gulls: there are usually only two staccato notes per second, as opposed to four in, e.g., European or American Herring Gull. For a recording and sonogram of a displaying pair of the latter taxon, have a look at the recording >>>HERE<<< and note that about 3.5 – 4 staccato notes are delivered per second (from seconds 3 to 7), at a frequency of c 1000 to 4000 Hz.

Yet, there are noticeable differences between the three “Iceland Gull taxa” as well. Recordings have become available in recent years, except for Kumlien’s Gull, so I recorded this taxon myself in Newfoundland in January and February 2013. When discussing these recordings with Magnus Robb, it became clear that especially Thayer’s Gull is somewhat different. While gull long calls are variable, e.g. differing between male and female and depending on the kind of interaction that is going on, the difference may be significant, and has actually been hinted at before: Sibley (2000) described the long call of Thayer’s Gull as lower and flatter than (American) Herring Gull, while Iceland Gull is said to be ‘shriller’ (i.e. higher).

Thayer’s Gull

Thayer' s Gull (near) adult Choshi, Japan, 11th March 2013. Peter Adriaens

Thayer’ s Gull (near) adult Choshi, Japan, 11th March 2013. Peter Adriaens

So what do these birds sound like? The Macaulay Library has three recordings of adult Thayer’s long calls and two of flight calls. You can listen to them >>> HERE <<< . As the recordist also comments, these calls sound rather deep. If we put this into a sonogram, we can see that the fundamental (i.e. lowest) staccato notes start below 1000 Hz and have a rather flat, gently arched shape. There are also some guttural sounds, which go below 500 Hz.

Adult Thayers Gull, flight calls & long calls. Churchill, Canada 3 June 2009 (from Macaulay Library)

Adult Thayers Gull, flight calls & long calls. Churchill, Canada 3 June 2009 (from Macaulay Library)

Note also that the flight calls sound quite low, starting clearly below 500 Hz.

Thayer's Gull (near) adult, Choshi, Japan, 11th March 2012. Peter Adriaens

Thayer’s Gull (near) adult, Choshi, Japan, 11th March 2012. Peter Adriaens

Another recording of Thayer’s Gull long call is available on the Stokes CD ‘Bird songs of West America’. Again, the sonogram shows deep staccato notes (starting below 1000 Hz) with a flat shape.

Thayer' s Gull long call from Stokes CD ‘Bird songs of West America’.

Thayer’ s Gull long call from Stokes CD ‘Bird songs of West America’.

Iceland Gull

Adult Iceland Gull, Grindavik , Iceland, 28 March 2010. Peter Adriaens

Adult Iceland Gull, Grindavik , Iceland, 28 March 2010. Peter Adriaens

Compare the Thayer’s Gull calls above to the following recording of a displaying adult Iceland Gull (nominate glaucoides), made by Magnus in Iceland in spring:

Transferring this to a sonogram reveals that the call notes have a distinctly peaked shape, are all clearly above 1000 Hz and therefore higher pitched than in Thayer’s Gull:

Adult Iceland Gull long call, Iceland, Magnus Robb

Adult Iceland Gull long call, Iceland, Magnus Robb

Goethe (1986) based on several hundreds of recordings made in breeding colonies in Greenland and on birds in captivity, also describes the long call of adult Iceland Gull as higher than 1000 Hz. He also found it to be 500 to 700 Hz higher than in Herring Gull.

Adult Iceland Gull, Grindavik, Iceland, 23 March 2010. Peter Adriaens

Adult Iceland Gull, Grindavik, Iceland, 23 March 2010. Peter Adriaens

Further recordings of nominate Iceland Gull can be found on commercial CDs such as Schulze’s ‘Bird Songs of Europe, North Africa and the Middle East’ – though the long call on there is that of an immature bird.

Flight calls can be heard from about the 24th second in Magnus’ recording (first recording above and in short section extracted in 2nd recording directly above). These sound higher pitched than in Thayer’s Gull. In the sonogram, they are clearly above 1000 Hz:

Adult Iceland Gull flight call, Iceland. Magnus Robb

Adult Iceland Gull flight call, Iceland. Magnus Robb

Kumlien’s Gull

Adult Kumlien's Gull Newfoundland, 22nd January 2013. Peter Adriaens

Adult Kumlien’s Gull Newfoundland, 22nd January 2013. Peter Adriaens

The long call of Kumlien’s Gull seems similar to Iceland Gull, though perhaps sounding even higher – which is a bit unexpected in a taxon that is seen as intermediate between Thayer’s and Iceland Gull, or even as a hybrid between the two by some. In any case, the long call is clearly higher than in Thayer’s Gull, with the fundamentals starting above 1000 Hz. The flight calls sound higher pitched too; in the sonogram, they are at about 1000 Hz or higher, while Thayer’s flight calls start below 500 Hz already.

Long calls

Kumlien’s Gull adult Long calls (best 2) Newfoundland Jan- Feb 2013. Peter Adriaens

Kumlien’s Gull adult Long calls (best) Newfoundland Jan- Feb 2013. Peter Adriaens

Kumlien’s Gull adult Long calls (best 3) Newfoundland Jan- Feb 2013. Peter Adriaens

Kumlien’s Gull adult Long calls and Flight calls Newfoundland Jan- Feb 2013. Peter Adriaens

Kumlien's Gull adult Long calls (best 2) Newfoundland Jan- Feb 2013. Peter Adriaens

Kumlien’s Gull adult Long calls (best 2) Newfoundland Jan- Feb 2013. Peter Adriaens

Kumlien's Gull adult Long calls Newfoundland Jan- Feb 2013. Peter Adriaens

Kumlien’s Gull adult Long calls Newfoundland Jan- Feb 2013. Peter Adriaens

Adult Kumlien's Gull Newfoundland, 1st February 2013. Peter Adriaens

Adult Kumlien’s Gull Newfoundland, 1st February 2013. Peter Adriaens

Flight calls

Kumlien’s Gull adult Flight calls Newfoundland Jan- Feb 2013. Peter Adriaens

Kumlien's Gull adult Flight calls Newfoundland Jan- Feb 2013. Peter Adriaens

Kumlien’s Gull adult Flight calls Newfoundland Jan- Feb 2013. Peter Adriaens


It seems interesting that Thayer’s Gull appears to have a deeper, flatter voice than Iceland, Kumlien’s and even Herring Gulls. While I fully realise that many more recordings are needed, especially from the breeding grounds, I simply hope that the above information provides a fresh look at an old problem. Perhaps the taxonomic debate cannot be settled by measuring skins in musea. There is still a need for more detailed and controlled research, which should probably also take into account voice and ecology. Thayer’s, Kumlien’s and Iceland Gull certainly behave like three distinct populations; each one has its own breeding and wintering range, for instance. Each one seems to have its own plumage traits (Howell & Elliott, 2001; Howell & Mactavish, 2003) and probably also voice. If the whole Iceland Gull complex is just one big cline, as suggested by e.g. Snell (2002), how can there be three distinct populations? And if Kumlien’s Gull is merely a hybrid, as advocated by e.g. Weir et al (2000), why does it have its own range? Surely the taxonomic debate can only be settled when there are firm answers to such questions.


Goethe, F. 1986. Zur Biologie, insbesondere Ethographie der Polarmöwe (Larus glaucoides Meyer, 1822). Ann. Naturhist. Mus. Wien. 88/89(Ser. B):113-146.

Howell, S & Elliott, M T. 2001. Identification and variation of winter adult thayer’s gulls – with comments on taxonomy. Alula 7 (4): 130-144

Howell, S & Mactavish, B. 2003. Identification and variation of winter adult Kumlien’s Gulls. Alula 1: 2-15

Snell, R. R. 2002. Iceland Gull (Larus glaucoides), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online:…0.2173/bna.699

Weir, D. N., Kitchener A.C., and McGowan R. Y. 2000. Hybridization and changes in the distribution of Iceland gulls (Larus glaucoides/kumlieni/thayeri). J. Zool., London, 252: 517-530

Trickier birds would be very interesting to record…

Adult Kumlien's Gull (dark individual), Newfoundland, 25 January 2013. Peter Adriaens

Adult Kumlien’s Gull (dark individual), Newfoundland, 25 January 2013. Peter Adriaens