Monthly Archives: December 2010

heinei Common Gull

Can you ‘do’ first winters?

Found myself asking that question once again. Yesterday came across the bird below at Catcliffe Flash, Sheffield. It’s a first winter Common Gull- no argument. However unlike many/most first winters normally seen in the U.K. This one has couple of extra dark bits. These are:

  • Rump and uppertail unusually well barred with brown
  • Dark mottling over white areas of the tail
  • Dark barring on longest auxiliaries

Note the tail band on this bird isn’t that broad: On some Common Gulls wintering in Japan, the black tail band is wide enough to reach the edge of the uppertail coverts. On others however the rump and tail pattern is very similar to this (Sheffield) bird.

I think the third feature (auxiliary barring) is not uncommon, but the tail and rump pattern on this bird seemed to be to be a bit unusual.

I have an assumption which may or may not be correct.

The eastern most taxa Kamchatka Gull kamtschatschensis has the most dark on the tail, most barred rump and most barring in underwings coverts. My assumption is that as you go ‘east’ the dark pigmentation increases in Common Gull, terminating in kamtschatschensis.

Thus, such individuals as the bird below might be identifiable heinei  – ‘Russian’ or Siberian Common Gulls. Yes or no?

Any thoughts? Input  very welcome! How common is this tail and rump pattern combo in Western Europe?

All photos Catcliffe Flash, Sheffield, 21 December 2010.

Marsh Hawk

The “Marsh Hawk” Conundrum

Julian Hough (all photos by author unless otherwise noted)

Gripper! Me holding a HY male, Northern Harrier, Cape May, NJ, USA, September 1990. Who’d have thunk back in my 20s, that these awesome beasts would not only encumber me with headaches and sleepless nights, but also many ‘wasted’ hours in front of a computer that I can never get back!

With all the current ‘hudsonius hysteria’, I hope the following may be of interest and is put forth here, not as an authoritative, in-depth identification piece but as an interesting resource, especially for those lucky enough to have seen the one of the putative HY (Hatch Year=juvenile/first-year) Northern Harriers that have graced Ireland and Norfolk recently. If anything, it is to present a pictorial expansion on criteria currently being discussed to help separate these two species/sub-species.

A typical HY male, Connecticut, October. Streaking on the underparts is variable. The sides of the breast and flanks are lightly streaked, but typically heavy streaking is absent from the central belly as is often shown by many cyaneus. Although some birds can show pencil thin-streaks on the lower belly, you don’t want your hudsonius to have thick streaking in that area!

Flash Back

It all began for me back in 2008 when I posted a request on the Surfbirds forum asking for information on ‘rufous-plumaged’ juvenile Hen Harriers (C. cyaneus). It was to solicit information that might provide insight into what features might be useful in separating these individuals from vagrant juvenile Northern Harrier (C. c  hudsonius or C. hudsonius?)– an identification issue I had been interested in from my autumn experiences in Cape May, NJ, USA. These warm-plumaged juv cyaneus were often described as variants, but a perusal of books and online galleries show that these juvenile birds are not as uncommon as was previously thought. Documenting how these birds might be separable from vagrant hudsonius was a logical first step in attempting to solve the problem. I had no idea at the time, that such interest in this race/species would soon go “Super-Nova”.

Flash Forward

Anyway, fast forward to 2009 and a hudsonius-like harrier seen on North Ronaldsay by Alex Lees, Paul Brown  and John Bell kicked off all sorts of interests in the same arena. Described as a veritable flying “Terry’s Chocolate Orange” it seemingly sported a nice quota of field marks suggestive of hudsonius. The essential reference was John Martin’s excellent paper in BB that documented the first acceptable juvenile on Scilly in 1982. From the available photo-evidence of the North Ron harrier, it was apparent from a rarities committee perspective that it might fall short of meeting criteria necessary to nail it as a hudsonius. It was this bird, and correspondence with Alex Lees, John Martin, John Bell and Martin Garner, that instigated talks about what features were valid and consistent in proving a Northern Harrier in a vagrancy context. I am also lucky enough to live 10 minutes from one of the best hawk watching spots in New England and get to see good numbers of “Marsh Hawks” each autumn. I was able to photograph quite a few.

Another typical HY male, Connecticut, January. Taken at sunset, the bird is saturated by the setting sun. Note the ‘boa’ effect extending around under the chin and streaking most notable on the flanks, not central belly.

Is three two too many??

Eerily, in October 2010, sharp-eyed Irish birder Tom Kilbane found a bird at Tacumshin. Nicely photographed by Killian Mullarney, it was as perfect candidate and ticked all the pre-requisite boxes. Cool! It seemingly could be done!  Within weeks, photos surfaced of another bird at Kilcoole, Ireland that looked equally convincing but additional information was not forthcoming. Then, in what might have seemed a cruel twist of fate another individual was claimed in Norfolk (Mark Golley, Stuart White) that seemed destined to tar and feather these ‘good’ birds. One bird, awesome! two…err, OK,…. but THREE birds in almost as many weeks seemed to defy logic. England winning the World Cup again was more likely! Probability and common sense dictated three hudsonius in one fall (after an absence of 28 years) couldn’t be true ? Surely this east coast individual was the “I told you so cyaneus” – the one individual that would reinforce the notion that maybe we didn’t quite have a grip on just how difficult telling cyaneus from hudsonius could be.  In the face of improbable odds, the photos of the Norfolk bird again ticks all the right boxes and appears as good a hudsonius as any other claim – kudos to the finders for putting out their suspicions in the face of such improbability! So, on the face of it, the only explanation is that there seems to have been a small arrival of Marsh Hawks this fall, -an hypothesis that could be superficially supported by weather patterns and the discovery of other Nearctic vagrants in 2010. Or, we are all just going completely insane!!

The final coup de grace in this drama was when Mark Newsome posted photos of a male bird he had photographed in Durham in February 2009. ( It proved to be an adult male Northern Harrier – the first undisputed male for the Western Palearctic and reaffirmation that these birds do have the stamina and wing-loading to make it across the Atlantic.

HY female (left), HY male (right) Cape May, October – note dark brown iris in female and bluish-grey in HY male. The extent of white around eye is often broken at rear. HY Northern Harriers invariably show well-marked streaks across upper breast but others can be almost uniform below. (Photos: Alec Humann, left, R. Studholme, right)

Field marks-are there any useful ones?

John Martin’s BB paper (also a chapter in ‘Frontiers in Birding’), which still stands the test of time, laid out the criteria most observers use for reference. Other features of potential use in separating  hudsonius were recently discussed and included; the width of the middle dark bar on the underwing secondary coverts; the prominence of the dark boa and the number of dark bars on the longest three primaries. Examining photos, I also had noticed independently the propensity for hudsonius to lack streaks on the undertail coverts – unfortunately a feature also shown by some cyaneus.

HY male, Cape May, NJ, September (same bird as in header photo) – note dark, chocolate upperparts and “Terry’s Chocolate Orange” outer tail feathers and wing coverts.

In an effort to validate and quantify some of these features, I had enlisted the help of Paul Napier and the Raptor Banding Project at Cape May, who kindly agreed to collect data and take some photos.  To them, particularly Robert Studholme, I owe big thanks and to Alec Humann for use of their images. The image below shows the features that were analyzed.

The following are summarized comments from data collected on 40 (25 male and 15 female) HY Northern Harriers banded at Cape May, New Jersey in October 2010.

  • Primary bars (excluding the dark tip) on P9-7 varied on both male and female. Males averaged 6 bars (lowest 5, highest 7) while females averaged 5.6 bars (lowest 5, highest 8).
  • On the males, the middle secondary bar was always significantly narrower, but in females it varied with some females having a broader bar equal to A and C, especially on S4 – 6.
  • In the hand, the undertail covert feather shaft streaking was obvious on almost all the males* but this streaking was absent on the females.

* These shaft streaks almost certainly undetectable in normal field conditions.

HY (sexes unknown) – note variation in primary barring, width of the dark secondary bar (B) and how many dark secondary bars are visible. These photos show the amount of primary barring is variable; typically 5-8 (average 6) excluding the dark tip and is not really useful in isolation. One cyaneus with 6 bars has been documented from Orkney (photographed by A. McGeehan)

HY male (left) and HY female (right). note rich cinnamon undertail coverts/vent that lack obvious dark streaking shown in many cyaneus. Some HY males show a darker feather shaft as shown, but these should not be visible in the field. While many cyaneus show more distinct brown or blackish  streaks here that are visible in the field, some can show clean undertail coverts.

It’s interesting to note that out of the 40 birds trapped, 25 of them were males (62.5 %) and 15 were females (37.5%).

A glance through my (limited) photo collection shows that of the birds I could age from my photos (on eye colour) most were males. Photographing random birds at random times suggested a higher proportion of males to females.

It is interesting to compare the above features with those of the current claimed hudsonius. Personally, I had gone backward and forwards on whether I thought I could “do” them, especially as it is obvious that some cyaneus can be so similar as to make the identification in many field condition very difficult, if not impossible.

HY male, Connecticut, January.  Note pattern of underpart streaking and middle secondary bar. This bird is well lit from below by light reflected off snow and appears less saturated.

Since many of these features may be difficult to accurately note in the field, obtaining photo-documentation seems a pre-requisite for a claim of any putative hudsonius.  In illuminating discussions in private and on Bird forum and Surfbirds Forum, it had become clear that this issue is difficult at best due to the lack of any single diagnostic field mark. Identification seems only possible using a suite of characters and only the “classic” birds will prevail. In a vagrancy context, they are the raptor equivalent to ‘smithsonianus’ Herring Gulls!

HY, Connecticut, October. A more uniformly patterned bird with only 4 -5 apparent bars on the outermost primaries. What would you do with this in Europe!!

Continued research and documentation will create a more informed (and at the same time, probably confusing) picture. More research into cyaneus and determining how many birds can actually show a similar suite of features is needed. A careful examination of photos of some of these pseudo-hudsonius shows them to be lacking in some aspects and we must take care not to muddy the identification waters unnecessarily.

HY, male, Connecticut, November.

Based on current knowledge, the criteria used for identifying hudsonius is certainly being sharpened and may yet prove to be a moving goalpost. Future data may need to be reformed, revised and validated under more scientific controls. Until then, based on what we have, birds conforming to the suite of characters described above should be taken seriously. The recent claims (including the North Ron bird in my opinion) have been thought-provoking and the finders of these birds deserve applause for having their wits about them to bring to light their presence which is not an easy task out in the field!

And finally…an “easy “one. Adult Male Northern Harrier, Connecticut, November. Colloquially known as “Grey Ghosts”, adult males are exquisite. They are more marked above than cyaneus with a thick, black trailing edge on the underwing and small brownish-orange markings on the upper flanks and undertail coverts. Younger adults have a more brown-washed head (often appearing more “hooded”) and are often more extensively spotted.

Thanks to Alex Lees, John Martin, Martin Garner, Mark Golley, Killian Mullarney, John Bell, Jerry Liguori and Bill Clark for illuminating and educational discussions on this topic. Big kudos to Paul Napier and the Cape May Raptor Banding group.  Special thanks to Martin Garner for allowing me to hijack his educational blog.

American Herring Gull

Not … but scary!

For whatever reason, it seems that some 2nd winter European Herring gulls can be INCREDIBLY dark- with virtually all dark tails and well-barred rumps. The mimic American Herring Gulls. I don’t know for sure but suspect they are part of the argentatus variation. Chris Gibbins photographed this superb looking bird yesterday at Fraserburgh , Grampian.

P.S. Please check out Chris’s superb blog, especially his recent Caspian Gulls from Lithuania:

All photos Chris Gibbins, Fraserburgh, Grampian, 19th December 2010

Evening Event: 12th January, Sheffield

Gulls on Wednesday

“Talks given by Martin are much more than a clear, enjoyable and interesting presentation on a (bird ID) subject. As I witnessed on the Dutch Birding Day in 2008, he has the gift to entertain his audience from the first second in a way that will help you remember the message for years. To everyone who has the opportunity to attend a presentation by Martin I would say: GO!”

Nils van Duivendijk, author: Advanced Bird ID Guide

Kind words from Nils- I will try and live up to them this Wednesday evening. Content includes:

  • ‘Learning the Gulls’
  • Stories of Discovery
  • New frontiers in Gull ID

Should be something for everyone. Hope to see you there.

Adult Siberian Common Gull. Chris Gibbins. These reach Britain every winter. They largely go unnoticed.


Wednesday 12th January 2010

Start Time: 7:15 pm (so arrive at 7:00!)

Sheffield University Arts Tower

Lecture Theatre 5

more details :

“One of my most enduring memories of the 2009 International Gulls Meeting is Martin Garner’s talk entitled ‘ What are the next frontiers of large gull identification?’.  Having already read Martin’s ‘Frontiers in Birding’ book I was expecting something good but his relaxed and engaging style made it absolutely inspirational.  The highlight of the weekend’s lectures?  –  undoubtedly!”

Chris Hind, Cumbria, UK

Lesser White-fronted Goose


With debate over the provenance and even identification of  a Lesser White-fronted Goose (with Taiga Bean Geese) in Norfolk, here’s a couple of hybrid Lesser White-fronted Geese which I’ve come across previously in the UK. One presumed wild and one not. Also a couple of presumed (and seemingly) normal Lesser White-fronts in captivity.

Adult Lesser White-fronted Goose in captivity. Martin Mere WWT. October

Rother Valley C.P. hybrid

The Rother Valley duo. Variously reported in the area over several years. I came across these 2 together  RVCP in October 2008. At greater distance the Lesser White-front type looks pretty convincing. dark squarish head, prominent yellow orbital ring, long-looking primaries, short pink bill and white blaze looking OK. Its only when you see it a bit closer that it just doesn’t quite look the ‘full shilling’. Bill a tad long, white blaze not quite right.Even then it can be hard to put a finger on exactly why. In a distant wild goose flock I could be fooled, I think.

Few more pics below from Oct. 2008

And what the heck are you? (I think he would like to be Blue Ross’s Goose- one day!)

Slimbridge hybrid Lesser White-front

I found this bird amoung the Russian White-fronts at Slimbridge on 15th February 2007 (It gets a mention in the ‘Frontiers in Birding book). It looked like a Lesser Whitefront on steroids! It was large but with big dark, squared head, reduced black belly streaked, prominent yellow orbital ring, steep shortish pink bill and more extensive white. Although only seen the once that winter, it had been seen the previous winter regularly by WWT and we had come to the same conclusion on the bird’s ID.

Captive adult Lesser White-fronted Goose, Martin Mere WWT, March 2005

Sheffield’s Steppe Shrike update

Looking good…

Having reviewed literature, shared notes with local birder Jim Clarke, who also saw the bird well and sought advice, this bird still appears to be a good example of homeyeri Great Grey Shrike: or as the Russians call it Steppe Shrike! At least it has  a host of homeyeri characters. I may be there is a yet-to-be-determined line of characters that acceptable vagrant homeyeri must show.  Right now, I don’t know which side of such a line, this bird will fall.

For now that doesn’t really matter to me. I have learnt a great deal already about the ‘Great Grey Shrike group’. I plan to have a look at some specimens soon and keep exploring the subject. As so often the enjoyment has been in the discovery, and it’s not over yet!

What follows are photos and text of:

1) a typical 1st winter Great Grey Shrike (nominate excubitor).

2) labelled photos of the Sheffield bird, indicating what can be noted as ‘different’.

3) photos of presumed ‘homeyeri’ to give and idea of appearance which can be compared with the Sheffield bird.

4) some apparent excubitor/ homeyeri intergrades.

5) finally comments from 3 folk with expertise in the subject

1) nominate excubitor Great Grey Shrike

1st winter Great Grey Shrike sp. excubitor. Spurn, East Yorkshire. 20th November 2010. Nigel Genn.

Aged by pink bill base, weak loral pattern, pale tips to greater coverts and worn (brownish) primaries.  Check out the short patch of white at primary bases, grey rump and upper tail coverts (same as upperparts). This bird may have some white on the secondary bases, as a section of these are covered by the greater secondary coverts, unlike on the primaries. Open wing or flight views would be needed to check this. excubitor certainly is variable (some have no white at secondary bases, others quite a bit) and we may regularly get some with gene introgression from homeyeri range. Being familiar with the normal features of nominate excubitor is good starting point.

1st winter Great Grey Shrike sp.excubitor. Spurn, East Yorkshire. 20th November 2010. Nigel Genn.

Great shot of the tail! Revealing extensive black typical of excubitor, with black in every tail feather. Some can have all white outermost feather T6  but black in T5 points towards excubitor or intergrade. Gives an idea how very different the tail pattern is on  classic’ individuals of excubitor and homeyeri respectively.

2) The Sheffield Bird

Key features of the Sheffield Shrike– noted in the field and visible in photos. No single ID feature but combined seem make strong case on current knowledge for identification as homeyeri, though more research required.

  • Paler, cleaner less saturated  upperparts- also noted by several observers who saw the bird
  • Large broad white scapulars patch diffusely bleeding into grey. More extensive than normal for excubitor
  • Odd retained juvenile head pattern including grey lores as per crown and brown forehead (and quiet bright pinky bill base). This combination seems to be normal on some homeyeri and leucopterus specimens, unusual/ exceptional for excubitor. The brown tones on the forehead of the Sheffield bird seems a particularly interesting attribute. Siberian ssp. sibiricus and Northern ssp. borealis/ invictus Grey Shrikes have obvious brown- toned upperparts in juvenile/ 1st winter plumage.  Specimens of both homeyeri and more eastern leucopterus seem to show limited brown feathers on the upperparts, particularly the forehead. I don’t know if excubitor in core range show the same kind of brown tones.
  • Classic homeyeri tail pattern present. An essential character to confirm, without which claims of homeyeri will probably always fall short. T5 appeared to be wholly white. Jim Clarke watched it snag the tail and as far as he could see T5 and T6 looked wholly white- just couldn’t quite get a tiny bit of the inner web near the base as obscured by overlying feather. The first proper black on my photos is on T4 – a bar part way in middle of outer web.
  • Wing pattern LONG white at primary bases – this can be measured in comparison to length of longest primary covert (from pale tipped alula to start of white). It’s clear that the white on this bird is longer than on many excubitor. Be interesting to see a more accurate length of white at the primary bases can be ascertained in comparison to the long primary covert.
  • Extensive white on secondaries. On closed wing appearing as broad ‘rectangular’ running about a 40 degree angle to the primary patch and  reaching down the wing about 75% as long as the primary patch on the folded wing. In flight shows extensive white on secondaries of similar length to white on primaries. Many apparent intergrades show shorter length of white in secondaries.
  • Rump whitish– this was tricky especially in changing light conditions Both Jim C.  and I agreed on independent views that rump was clearly off white or whitish especially compared with the grey uppers.  Confusingly at times the uppertail coverts looked white, other times greyer. Then I realised that white translucent feathers overlying black tail can look misleadingly grey.

Photos not great (better than none!) but labelled to show features. These features were much clearer and carefully recorded through 32 X ‘scope!

Here’s the spread tail – classic homeyeri pattern, confirmed by field views. I know the rump area look greyer here! Can’t explain why, but in careful field views the rump and uppertail coverts were similar tone to underparts- basically whitish- not gleaming but slightly off white, obviously paler than rest of upperparts.

This in-flight shot labelled by Ian Lewington shows his assessment of feather tracts. Somewhat confusingly in some flights poses, shrikes can hold the inner part of the wing semi-closed, thus hiding the true pattern of white, as here. Some of the white in the secondaries is hidden underneath the bunched greater coverts. The upper (labelled) bird is the Sheffield Shrike. The lower bird in similar pose is an apparent intergrade excubitor/ homeyeri from Krakow, S.Poland in November 2009. It differs from the Sheffield bird in having more of ‘step’ between white primary and secondary ‘bars’ and black spot on P5. See full range of shots of the latter bird and how white in wings varies greatly in appearance:

(with thanks to Grzegorz Neubauer and Ian Lewington)

3) photos of presumed ‘homeyeri’

Some here from Kazakhstan:

Photos below of adult bird taken in NW Romania in September 2009 by Luca Dehelean.

Panov (in press) notes the boundary of the ranges of nominate excubitor and homeyeri  at the border of Romania and the Ukraine and a little eastward.  Thus birds seen in south and east Poland and Northern Romania are likely to includes ‘good’ homeyeri and ‘obvious’ intergrade types.

Adult Steppe Shrike ssp. homeyeri. Arad, Romania. September 2009. Luca Dehelean. Other may identify as not 100% homeyeri– it may come down to where we draw the line!

The extent of white on the closed wing (here with  black greater coverts slightly dishevelled) is very similar to that on the Sheffield bird as it appeared in the field.

same bird as above showing classic homeyeri tail pattern

Same again showing extent of white on open wing. Also note how whiter rump and upper tail coverts appear different in above 2 photos, and not necessarily an easy feature to ‘read’ in the field.

homeyeri (left) compared nominate excubitor (right) Patrick Engstrom, September, Sweden (from Alula magazine).

This is one of Sweden 6 accepted records of homeyeri. Critical features visible in the photo include homeyeri tail pattern, longer section of white at primary bases, and broad rectangular of white at secondary bases. Both the wing and tail patterns are very similar to that of the Sheffield bird. The primary projection also looks a tad longer doesn’t it?

4) Some apparent excubitor/ homeyeri intergrades.

Intergrades and possible good homeyeri from Sweden. All trapped birds appear to be intergrade to me, but one or more of the ‘field photos’ may represent good homeyeri. Unfortunately key features such as tail pattern not ‘nailed’.

and again this bird from Krakow, S. Poland, November 2009:

Below intriguing set of photos of 2 apparently fresh juveniles from NE Poland. These birds taken same time, same area and possibly from same brood? by Lukas Krajewski in June.

Photos above taken in June so it must be a fresh young bird, isn’t it? The grey lores and wing pattern (especially the white trimmed secondaries) are homeyeri characters. However the lack of extensive  white in the scapular fringe or rump/ uppertail coverts and the big ‘step’ between white base primaries and secondaries point to an ‘intergrade’. The bird below was photographed- same time, same area, NE Poland, June.

This look like a pretty normal fresh juvenile nominate excubitor. NE Poland, June, Lukas Krajewski.

5) Expert Comment

Evgeniy Panov – author of new book on Shrikes

Dear Martin,

It seems to me that your bird looks like a typical homeyeri.

So my congratulations with  recording a new bird subspecies for UK.

All best wishes, Evgeniy

Lars Svensson (thanks to Alan Dean):

I contacted Lars Svensson and he replied that he has researched the topic of the ‘grey shrike’ complex in some depth, including excubitor, homeyeri and the notional ‘leucopterus’. Many conclusions from these studies will be presented in the passerines volume of forthcoming photographic handbook of palearctic birds, which Lars and Hadoram Shirihai are co-authoring. For clarity, it is better that the full discussion in that publication is consulted rather than attempting an over-concise summary here. Lars has, however, offered the following comment on the photos of the Sheffield bird:

‘I took a look at the photographs. To me this is just about enough characteristic to be labelled homeyeri. Thus not a v. przewalskii [= ‘leucopterus’]. It is clearly a young male. It appears much paler and cleaner grey (bar the crown on images taken in shadow) than is normal for young excubitor. The wing patch shape and size is the wanted one, and on the tail I count two all-white outer tail-feathers and a r4 with dark limited to inner web (?) of inner 2/3. (Sharper images might refute or confirm this interpretation.)’

Thus, with the necessary proviso that his opinion is based upon an assumption that the photos are accurately representative, Lars is supportive of an id of homeyeri.


Grahame Walbridge:

“It’s a long while since we examined the skins at Tring, we examined them all but only looked closely at exhubitor, homeyeri & pallidirostris. The Sheffield bird appears to show typical wing and tail pattern for homeyeri with additional supporting features. On that basis, it is most certainly not exhubitor (in my opinion) so that just leaves the question of a possible intergrade. Since it shows no intermediate characters there is no reason to support that theory……



Interesting UK Grey Shrike

Forest of Dean, March 2009

Here, some video grabs by Ian Lewington of a Great Grey Shrike from March 2009. It goes with the next post. It illustrates that ‘interesting’ Great Grey Shrikes have been around. This one has clearly white rump/ uppertail coverts. The tail pattern looks interesting though can’t be fully resolved. The white on the secondary bases is a little less than you would hope for on homeyeri claim (too short), but the white on the scapulars does look extensive. I wonder if it has some homeyeri in it.

Where’s it from? I don’t know. What I have learned over the years is to collect data and see how it pans out. We may be getting true homeyeri Steppe Shrikes and some genuine intergrades more often than the ZERO British records indicate! It’s all about paradigms.We see what we think should be there. History teaches us, how much we miss!

All videograbs, Forest of Dean, March 2009. Ian Lewington.