Welcome to my Identification Guide to Winter Gulls – Part 2. In this guide we will compare the three most common large gulls you are likely to encounter in a UK winter: Herring Gull, Lesser Black-backed Gull and Great Black-backed Gull. As with all things birds, and particularly when it comes to gulls, nothing is absolute. Gulls demonstrate a great range of plumages throughout their lives with much variance depending on exact age, place or origin, race, time of year, wear and tear etc. Moults in some that migrate are delayed or retarded, more northern races can show signs of hybridisation with other species and have different coloured legs etc. However, that’s all detailed stuff; all we need to concentrate on is the general look and feel.
These larger gulls take, on average, 4 years to reach maturity and become full adults. For the first couple of months of life they are clad in mottled brown/black juvenile plumage. A late summer/autumn moult will result in some feathers, mainly around the head, but also across the mantle and some other body feathers, becoming a little more crisply patterned. Subsequent years, (starting in spring and lasting until autumn), will see the plumage edging towards the adult state, when beak, and to some extent, eye colouration will also change. Using a combination of these pointers can provide a good indication of age, which for our purposes (because its used widely, we’re dealing with winter birds and it makes logical sense) we will call 1st, 2nd, 3rd Winter and Adult. You may find other terminology used in some reference works which refer to 1st Calendar Year, 2nd Calendar Year, etc or even ‘Basic’ and ‘Alternate’. All quite valid and proper, but unnecessarily confusing as far as this guide is concerned.
By far the most common large winter gull you will encounter will be the Herring Gull. In winter, our resident UK population will be swelled considerably by birds from Northern Europe, Scandinavia and Russia to make it very visible at most coastal localities, as well as at inland towns and farms. They are loud, feisty, bold and opportunistic; one reason they are so numerous.
Lesser Black-backed Gulls do nowadays winter in much smaller numbers, primarily in the southern part of the UK. Formerly, all migrated south to Iberia and even North Africa, but habits have changed either through climate variations or there being more opportunities for them to forage on landfill, pig farms etc. The wintering numbers here will be augmented by visitors from northern regions. They are far less emboldened than their close relative, and are seldom seen fighting over the spoils of discarded fish & chips.
The Great Black-backed Gull is a brute, is quite shy of people and is rarely attracted to hand outs. There are good numbers wintering in the UK, and as with the other species, these are augmented by immigration from northern latitudes. The species is really unmistakable when seen close to, but is most likely to be encountered patrolling along the coast or out to sea and at roost on lakes and estuaries.
Ok then, let’s have a more detailed look. I’m going to major on the Herring Gull for no better reason than they are the most likely you’ll come across, have general features common to all, and are, by a million miles, more easy to photograph! It’s necessary to use some specific terms for feathering, but I’m sure these will be easy to understand, i.e. main flight feathers (the wing tips) are ‘primaries’ – there’s 10 of those, the smaller trailing edge flight feathers are ‘secondaries’, then as you move towards the front edge of the wing there are a series of ‘coverts’ – greater, median, lesser and marginal. ‘Tertials’ is a term given to the feathers that sit at the base of the wing as it joins the body. At rest these are towards the end of the folded wing. Once you become familiar with these terms and the Herring Gull as a species, it should be quite easy to recognise something different.
Note: At all ages the Herring Gull has pink legs
Fig 1 – Herring Gull – 1st Winter. The juvenile plumage has been partly moulted to produce a bird with 1) mottled brown feathering on mantle and wings, 2) paler head and neck with some brown streaking, 3) dark eye, 4) black beak (sometimes with elements of a pinkish base), 5) notched tertial feathers (this is an important differentiator between Herring and lesser Black-backed Gull – see Figs 13 and 14), and 6) black primaries with a hint of pale tips.
Fig 2 – Herring Gull – 2nd Winter. The bird is now beginning to acquire some adult feathering to show: 1) pale grey mantle, 2) very pale head with much reduced streaking on neck, 3) dark eye (not reliable because some show a pale orange iris), 4) clear whitish tip to beak, 5) paler but still clearly notched tertials, and 6) dark primaries with pale tips becoming more visible.
Fig 3 – Herring Gull – 3rd Winter. Much more akin to the adult bird, but still obviously shy of full adult plumage: 1) mantle and wings pale grey with remnant brown markings on secondary and lesser coverts, 2) mainly white head with uniform dark streaking as per winter adult, 3) eye with varying degree of orange iris colouration (see Fig 11), 4) pink base to beak with distinct pale tip, 5) brown patterning on tertials much reduced, and 6) primary feathers showing clear white tips.
Fig 4 – Herring Gull – Adult. A crisp, handsome looking bird, the familiar seaside gull, with 1) uniform pale grey mantle and wings, 2) white head and neck with varying degrees of grey streaking, 3) pale yellow iris, 4) yellow beak with bold red spot near tip, 5) bright white tertials, and 6) black primaries with clear white tips.
Birds in Flight
Fig 5 – Herring Gull – 1st Winter. Points to note: 1) overall light brown mottled plumage, 2) pale patch on primary feathers contrasting with dark brown outer primaries, and 3) pale, lightly brown mottled rump with dark brown tail band edged in white.
Fig 6 – Herring Gull – 2nd Winter. Points to note: 1) pale grey mantle, 2) pale primary patch much more visible, and 3) darker, black tail band contrasting with mainly white rump.
Fig 7 – Herring Gull – 3rd Winter. Points to note: 1) majority of wing feathers pale grey with bars of light brown feathering on coverts, 2) black outer primaries, sometimes showing white tips or ‘mirrors’, and 3) bright white rump and tail with faint hint of light brown mottling.
Fig 8 – Herring Gull – Adult. Points to note: 1) uniform pale grey upper surfaces, 2) deep black outer primaries with white spots or ‘mirrors’, and 3) bright white rump and tail.
Head and Beak
Fig 9 – Herring Gull – 1st Winter. 1) Dark beak with pale pink base, 2) dark iris, and 3) densely mottled head and neck
Fig 10 – Herring Gull – 2nd Winter. 1) Clear pale tip to beak, 2) dark iris, and 3) densely mottled head and neck
Fig 11 – Herring Gull – 3rd Winter. 1) Beak mainly pale pink with distinct black band with hints of red forming on tip of lower mandible (gonys spot), 2) some degree of dark orange iris, and 3) densely mottled head and neck.
Fig 12 – Herring Gull – Adult. 1) yellow beak with red spot (gonys), 2) pale yellow iris, and 3) some degree of mottling on head and neck – not as extensive as in younger birds, although this vary widely.
The Lesser Black-backed Gull has increased its population markedly in recent years and is now a common breeder in towns and cities where it will form mixed nesting colonies with the Herring Gull. During this time, handsome breeding plumaged birds are a regular sight from spring through to autumn, but then tend to move south and/or disperse to a few favoured localities that provide rich pickings. They are nowhere as frequently encountered during winter as the Herring Gull, from which they can be distinguished in all plumage stages by their much darker overall colouration. Adults are easily told apart from Herring Gulls by their slate grey upperparts, but can then be confused with the Great Black-backed Gull, especially the more northern Lesser Black-back races that have darker backs than the UK birds. The Great Black-back Gull is, however, much larger and more heavily built and tends to shy away from humans. Oh dear, it does seem awfully complicated, but we’ll compare them and hopefully help eliminate confusion.
Let’s have a look at some basic differences between Herring and Lesser Black-backed Gulls.
Fig 13 – Herring Gull – 1st/2nd Winter. Note: 1) tertials are clearly ‘notched’, i.e. they are not one tone and have light notches eating into the dark background, 2) pink legs
Fig 14 – Lesser Black-backed Gull – 1st/2nd Winter. 1) Overall much darker toned. All dark tertials, 2) also has pink legs at this stage.
Fig 15 – Herring Gull – Adult. 1) Pale grey upperparts, 2) Pink legs
Fig 16 – Lesser Black-backed Gull – Adult. 1) slate grey upperparts, 2) A somewhat slimmer, more streamlined shape, and 3) pale yellow legs
The Great Black-backed Gull is the largest European gull, much bigger, bulkier and darker backed (adult) than the other species. However judging size is a rather subjective issue, and without being able to compare side by side can become meaningless. Then, other things will come into play such as the more ponderous flight, shorter wing proportions and general habits. For example a dark backed gull in a city centre is very unlikely to be a Great Black-back, whereas a dark backed gull patrolling offshore, harassing smaller seabirds is very likely to be this species. Development is slow in this bird, and it may take more than 4 years to reach maturity. 1st and 2nd Year plumage is very similar to the other species, but there are differences.
Note: the Great Black-backed Gull has pink legs at all ages.
Fig 17 – Great Black-backed Gull – 1st Winter. This bird was tucking into wrecked shellfish, crabs and lobsters following a North sea storm. It was also still pestering one of its parents, even though it was the February following its hatching. A big bird with 1) more evenly patterned plumage than Herring Gull, 2) pink legs with much more tibia displayed (compare Fig 1), and 3) white head with large, bulbous black beak.
Fig 18 – Great Black-backed Gull – 1st Winter. Demonstrating its tendency to concentrate on natural prey (dead or alive). Note: 1) Crisper, darker mottling on upper wing (compare Fig 5), 2) very noticeable dark secondaries, 3) relatively clean underside, and 4) white head contrasting with heavy, black beak.
Fig 19 – Great Black-backed Gull – 3rd Winter. Becoming adult like but note: 1) plumage with very dark brown/black tones, with no noticeable contrast with primaries, 2) Dark saddle, 3) white, largely unstreaked head, and 4) large beak with pale yellow tip, broken black band and hint of red gonys.
Fig 20 – Great Black-backed Gull – 3rd – 4th year (taken in late summer). Again demonstrating its preference for fresh meat. 1) Largely pink beak with dark black/red tip, 2) bright white head, and 3) dark mantle and wings (compare LBBG in Fig 16).
Fig 21 – Great Black-backed Gull – Adult. And here is the finished article: 1) Dark black back and wings, 2) pure white head and neck (compare Figs 15 and 16), 3) small beady eye which is pale grey/green with a red orbital ring (compare Fig 12), 4) large yellow beak with bright red gonys, and 5) pale pink legs
Just for completeness, and because it is always possible to encounter something unusual (especially in more northern localities of the UK), we can have a brief look at a pair of other large gulls, Glaucous Gull and Iceland Gull. These are high arctic breeders, but will venture south in winter, the extent of dispersal depending on weather conditions.
On average, the Glaucous Gull is between the Herring Gull and Great Black-backed Gull in size. As with all things gulls there is variation largely depending on sex, with females generally being smaller than males and some males being as large as Great Black-backs. Most birds seen in the southern regions of the UK are young ones, northern isles tend to have a higher degree of adults, but it is never common anywhere. In all plumages they are very pale birds and quite distinctive.
Fig 22 – Glaucous Gull – Adult. I apologise for the rather poor quality image, but this is a copy of a colour transparency I took sometime in the 1980s at Cley, Norfolk. This adult was given the nickname ‘Boy George’ and spent the winter patrolling the north Norfolk coast each winter between 1982 and 1990. He was so named because the original ‘George’, another regular wintering bird, frequented the same area between 1963 and 1979. Source: The Birds of Norfolk 1999. In this image you can see the relative size compared to a Black- headed Gull.
Fig 23 – Glaucous Gull – Adult. Boy George again showing: 1) very pale grey mantle and wings (compare Fig 4), 2) absence of any black feathering in wing, unlike all the common species that have black outer primaries, 3) deep pink legs, 4) extensive mottling on breast, and 5) mottling on head with small pale yellow iris in eye.
Fig 24 – Glaucous Gull – 1st Winter. 1st and 2nd winter birds are very similar with overall pale creamy plumage. Points to note: 1) all over very pale brown patterning, 2) large deep pink beak with black tip, and 3) dark eye.
Fig 25 – Glaucous Gull – 1st Winter. Another view of a young bird (probably 1st winter since this was taken in early April). The same features are visible as in Fig 24 but with better light the bird appears a shade darker, but still very pale, compare with Figs 1, 14 and 17
The Iceland Gull is smaller than the Glaucous Gull and approximates to Herring Gull in size, although of course there is great variation. Plumage is almost identical to that of Glaucous Gull at all ages, but the overall smaller size and shape should differentiate most birds. They originate from Greenland, but winter in Iceland and will move south from there in small numbers. As with the Glaucous Gull, they are almost exclusively coastal.
Fig 26 – Iceland Gull – 3rd Winter. Note: 1) very pale upper side, 2) rounded head recalling Common Gull – click here for comparison – 3) pink bill with black tip (compare Fig 24 for size), and 4) benign expression with eye having a pale yellow/green iris. Image: Ros Burrough.
Fig 27 – Iceland Gull – 3rd Winter. Same bird as in Fig 26 showing better the near adult plumage with very faint light brown shading, small head and relatively compact size. Image: Ros Burrough.
Fig 28 – Iceland Gull – 1st Winter. Note: 1) overall creamy brown mottling, 2) small, domed head, 3) two tone pink/black beak, and 4) lack of black feathers in wing.
Fig 29 – Iceland Gull – 2nd Winter. An older bird showing 1) moult into more adult, pale grey, mantle feathering, and, 2) small, rounded head shape.
Fig 30 – 1st Winter Iceland Gull showing overall creamy brown mottling, two tone beak and no black feathering.
Fig 31 – 2nd Winter Iceland Gull (left) showing relative size and pale plumage comparison with Common Gull (foreground) and 2 Herring Gulls (right).
That’s all I have! I hope this gives you some useful pointers towards identifying these rather impressive birds. Gull watching can be addictive, but always good fun and rewarding. The identification of various races and potentially new species therefrom, is improving all the time. There are now excellent reference works, and web sites, dedicated to gulls which will supplement the basic information I have provided. In this regard the Helm Guide – Gulls of Europe, Asia and North America – click here for more detail – is a marvellous resource.
Next time you feel like feeding or just watching gulls during winter, try and identify a few and let me know if this article has helped – without feedback I have little idea whether it fits the bill.
For other guides in the series click here
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