The Status and Occurrence of Common Gull (Larus canus) in British Columbia. By Rick Toochin and Don Cecile. Published: June 3, 2023.

The Common Gull (Larus canus) is a small gull species found breeding in the Old World from Europe to Northeast Asia (Adriaens and Gibbins 2016). Recently the Common Gull was officially split by the AOS in 2021 from the North American Mew Gull, now called Short-billed Gull (Retter 2021).  The Common Gull has three recognized subspecies: (Larus canus canus),(L. c. heinei), L. c. kamtschatschensis) (Moskoff et al. 2021). 

 

The breeding range of the nominate subspecies of the Common Gull (L. c. canus) is from Iceland eastward across Eurasia, from the Faeroe Islands, in Great Britain, into Scandinavia, and northern Russia eastward to northeastern Siberia (Anadyr and Koryakland), and south into central Europe (Netherlands and northern Germany) (Adriaens and Gibbins 2016). The second subspecies (L. c. heinei) breeding east generally north of 55°N along Volga River, Kirghiz Steppes, Minusinsk, Lake Baikal, northern Mongolia, southwestern Siberia (Stanovoy Mountains), to the southern region of the Sea of Okhotsk (Adriaens and Gibbins 2016). The third and largest subspecies (L. c. kamtschatschensis) also called “Kamchatka” Gull is found breeding from the northern region of the Sea of Okhotsk, the Kamchatka Peninsula, and the Kuril Islands, south to Sakhalin Island (Brazil 2009). The Common Gull has been found breeding on lakes in Armenia, northwestern Iran, and perhaps the Caspian Sea (Moskoff et al. 2021).

The Common Gull is a very adaptable species, breeding in both marine and freshwater habitats (Mullarney and Zetterstrom 2009). In the western Palearctic, the species is likely to be found on seacoasts or inland either near or at a distance from water (Moskoff et al. 2021). Common Gull’s are mostly found in lowland areas but can be found up to 900 m in Scotland and to 1,400 m in Norway (Moskoff et al. 2021). Most nest sites are found near lakes, pools, in bogs, or grassy or heather moorland, on open ground away from water, and cultivated grain fields (). On marine coastlines, Common Gull breeding habitat is varied: using small inshore rocky stacks, islets and islands, grassy and rocky slopes, sand dunes, and the foreshore (Adriaens and Gibbins 2016). This species uses shingle bars, stony islets, and marshes on rivers (Cramp and Simmons 1983). In Poland, colonies use sand bars without vegetation about half the time, the rest is divided between different vegetation types: dispersed with dwarf herbs (15.0%), dispersed willow (Salix spp.) bushes (17.4%), and thickets of tall willows, tall herbs, or steep banks (Wesolowski et al. 1985). Across Eurasia, the Common Gull is chiefly associated with lakes and large rivers; in the Russian Far East in Kamchatka, the subspecies (L. c. kamtschatschensis) nests on rivers, marshes, tundra, and islands in lakes (Dement'ev et al. 1968).

The Common Gull is a short-to medium-distance migrant (Adriaens and Gibbins 2016). Breeding populations in northeast Asia of the subspecies (L. c. kamtschatschensis) winter from the coast of southern Ussiriland in the Russian Far East and the Sea of Japan, south to southeastern Asia (Brazil 2009). Most breeding birds of central Russia of the subspecies (L. c. heinei) migrate to the Baltic, Black, and Caspian Seas and the Middle East, with some birds moving to southern Asia (Adriaens and Gibbins 2016). The nominate race (L. c. canus) is the least migratory, many moving relatively short distances and others being sedentary (Adriaens and Gibbins 2016). Birds breeding in Finland migrate only as far as Britain and Denmark (Moskoff et al. 2021). Other European populations winter from the Baltic to Brittany, with some reaching the Mediterranean (Burger and Gochfeld 1996). 

Spring migration of the nominate subspecies (L. c. canus) group begins departure from southernmost wintering areas from February into late March (Adriaens and Gibbins 2016) (mostly in second half of February and early March in Israel) (Shirihai 1996), peaking during mid-March to mid-April for adults, and late April to mid-May for first-year birds (Olsen and Larsson 2003, Adriaens and Gibbins 2016). In Europe, birds migrate through the maritime countries; however, numbers in central Europe have been increasing (Cramp and Simmons 1983). In Japan, the subspecies (L. c. kamtschatschensis) is generally gone from the wintering grounds by early May (Brazil 2009).

Fall migration has the adult birds leaving earlier than the juveniles (Moskoff et al. 2021). In Southern Scandinavia two main migratory waves are observable; the first involves Fennoscandian and Baltic breeders and begins in mid-June with second-years, adults peaking between mid-July into early October and juvenile birds in September–October (Adriaens and Gibbins 2016). The second peak probably involves adult Russian breeders, including some (L. c. heinei), and peaks during late October into mid-November (Moskoff et al. 2021). Most birds arrive in the Baltic and North Sea in the months of August-September; arrival at southernmost wintering localities is dependent on the severity of the winter (e.g., most south to Brittany in west, reaching Iberian Peninsula and Mediterranean only in the coldest winters) and is gradual, with birds arriving from late October into mid-January, most arriving in Israel in mid-November (Cramp and Simmons 1983, Shirihai 1996). Large-scale coastal movements are observed locally during passage periods. Large migrant roosts, of tens of 1000s of birds, occur in autumn, notably in Denmark and the Netherlands (Olsen and Larsson 2003). Birds of the group (L. c. kamtschatschensis) arrive in northern Japan at Hokkaido by late September and is common on the coastlines until late December, withdrawing as snow and ice appears; occurs in central Honshu from mid-October to early April, and has occurred as far south as Okinawa in January and February (Brazil 2009).

In most areas, habitat use during migration and winter is similar, with birds associated with nearshore waters and coasts, river estuaries, beaches, mudflats, harbors, and sewage outfalls and treatment ponds (Moskoff et al. 2021). Shortly after breeding, European birds shift to grassland and croplands as well as tidal estuaries; winters more often along seacoasts and harbors at southern limits (Cramp and Simmons 1983).

The winter range of the nominate subspecies of Common Gull (L. c. canus) is from the breeding range south to Iberian Peninsula, Mediterranean region, North Africa, Israel, Iraq, Persian Gulf, Black and Caspian Seas, Afghanistan, Pakistan (rare); also, coastal East Asia from Japan and Korea south to southeastern China and Taiwan (Vaurie 1965, Cramp and Simmons 1983, Shirihai 1996). Some breeding populations move little (e.g., present all year in Faeroe Islands and south Baltic Sea). Those breeding in Finland winter from Denmark to Britain, while other European birds’ winter from the Baltic to Brittany (Moskoff et al. 2021). Relatively few reach the Mediterranean; up to a few hundred occur in the Iberian Peninsula in the winter, where most are found on north coast, hardly any reaching the far south (de Juana and Garcia 2015). A few, mainly first-winters, reach the Moroccan Atlantic coast in winter (Thévenot et al. 2003). Birds in Eastern Siberian (L. c. kamtschatschensis) winter from the Southern Ussuriland coast and Southern Japan to Southeastern Asia, with a recent record from the Philippines at Luzon, from December 2013–January 2014) (Jensen et al. 2015). Central Russian breeders of the subspecies (L. c. heinei) winter in the Baltic, Black and Caspian Seas and in Middle East, some moving to Southern Asia; some birds of this race winter in Central Europe (Adriaens and Gibbins 2016).

In Europe the Common Gull is casual in Greenland (Olsen and Larsson 2003) and accidental to Spitsbergen and Bear Islands (Olsen and Larsson 2003); also, casual south in eastern Atlantic to the Azores, Madeira, Canary Islands, Mauritania (Cramp and Simmons 1983), and Morocco, Libya, and Senegal (Olsen and Larsson 2003). The Common Gull is a vagrant south to Nepal, Bhutan, India, and Pakistan (Cramp and Simmons 1983, Grimmett et al. 1999, Olsen and Larsson 2003). This species is accidental in the western Hawaiian Islands (Kure Atoll) and possibly Palau (Pratt et al. 1987). Also accidental in the southwestern Bering Sea to Commander Islands (American Ornithologists' Union 1998).

In North America, the nominate subspecies of Common Gull (L. c. canus) is a rare to casual species along the east coast from in winter (September-May) along Atlantic Seaboard with most records coming from Newfoundland and Labrador (Godfrey 1986) to New England with specimen records from Massachusetts, with scattered records from Nova Scotia, New Brunswick, Maine, Massachusetts (Veit and Petersen 1993), New York (Guthrie et al. 1999), Maryland, Virginia, and North Carolina (e-bird database 2021). There are also many records from Eastern Quebec, including specimen records, with a few summering records in recent years (e-bird database 2021). There are also increasing records inland to the Great Lakes region (e-bird database 2021). The central Russian subspecies (L. c. heinei) has not been recorded in North America (e-bird database 2021). The Common Gull (L. c. kamtschatschensis) is a casual vagrant in Alaska in the western Aleutians (Attu Island and Shemya Island), St. Lawrence Island, and Pribilof Island (St. Paul), based on photographs and specimens (Gibson and Kessel 1997). This subspecies of the Common Gull is accidental along the west coast to British Columbia (Toochin et al. 2018). There are photographed records from the east coast of North America of this subspecies from Pennsylvania, Connecticut, Massachusetts, Nova Scotia, Newfoundland, Quebec (e-bird database 2021). 

 

The identification of the Common Gull is covered in all standard North American, European, and Northeast Asian field guides. The Common Gull is a small gull species measuring 40-46cm in length, with a wingspan of 110-125cm, and weighs from 394-556 grams (Brazil 2009, Mullarney and Zetterstrom 2009). 

 

The Common Gull is a rather small white-headed gull with no distinct bill spot that is found commonly across much of Eurasia. The northeast Asian subspecies also known as "Kamchatka Gull" has also sometimes been considered a separate species but is evidently more closely related to the nominate than to Short-billed Gull (L. c. brachyrhynchus). For in depth discussion on the identification of the Common Gull please read Adriaens and Gibbins (2016) or it is recommended to read Sibley (2021). Good standard North American field guides that show good illustrations of the Common Gull and comparison to Short-billed Gull as well as other gull species include Sibley (2000) and Dunn and Alderfer (2011).

 

The following description is taken from Moskoff et al. (2021) unless otherwise stated.

 

The European subspecies (L. c. canus) are usually more finely spotted on head and neck in Basic plumage than is the Short-billed Gull. All Eurasian populations also differ from Short-billed Gull in having more extensive black on outer 3 primaries, extending to or nearly to primary coverts on outer 2 primaries. Although this difference is best determined on specimens, it may be discerned in flight or on resting birds. On folded wing, Short-billed Gull shows only a narrow black line along outer primary bordered by gray on remaining primaries visible below tertials and behind line of folded secondaries, whereas Eurasian subspecies shows a distinct angle of black from lower edge of tertials forward and down to outer edge of primaries. This feature may not be visible in field depending on bird's posture. The Central Russian subspecies (L. c. heinei) is larger, darker in all plumages and heavier billed than (L. c. canus). Adult has yellower bill and legs, the former often with a dark subterminal bar even in summer. The northeast Asian subspecies (L. c. kamtschatschensis) is largest subspecies and darker than (L. c. canus) in all plumages, although dark head markings of winter adult less pronounced than in (L. c. canus). In adult (L. c. kamtschatschensis) the iris can be pale straw-coloured, mid-brown or dark. 

Adult breeding (Definitive Alternate) plumage characterized by entirely white head, tail, and body, medium-gray mantle (back, scapulars, and wing coverts), large white tertial-crescent (tips of tertials), small white scapular-crescent (tips of lower scapulars), and black-tipped primaries with large white spots in outermost primaries, forming relatively large white patch at tip of wing. Adult winter (Definitive Basic) plumage differs from Alternate plumage in having heavy grayish-brown mottling and clouding on head and neck, especially the hindneck. The eyes are dark amber to dark olive-brown (often darker in breeding condition), but typically entirely pale yellow in northeastern Asian breeders, though rarely shown in other populations. Bill entirely yellow to greenish yellow (brightest on breeding birds), typically becoming marked with vague dusky band near tip of bill in winter; legs and feet variable but usually dull grayish green to yellow green, sometimes tinged pinkish (often brighter and yellower in breeding condition). Sexes similar throughout year. Size, bill shape, eye color, and wing-tip pattern vary geographically.

Distinctive subadult plumages occur from first fall through to 2nd year (Juvenile to Alternate II plumages; geographic variation is marked in these plumages). Birds in Basic II similar too adult, with more extensive black on primaries merging with black on primary coverts to form larger black wedge on outer wing (other minor differences include smaller white spots in primaries and greater number of dusky markings on head and bill). Juvenile plumage is heavily mottled with grayish brown, including forehead, becoming almost uniform brownish on lower breast and belly; tertials rather uniformly brownish with pale margins; back, scapulars, and upperwing coverts gray-brown with whitish edging (greater coverts paler overall than smaller coverts, which have a rather rounded shape to the tip of the internal brown patterning); bill dark, with paler pinkish- to yellowish-brown base; underwing coverts almost uniformly grayish brown (only diffusely spotted or checked) and underside of remiges silvery gray with darker tips to primaries. The rump and uppertail coverts white with heavy-brownish mottling or barring; the tail appears mostly dark brown with a narrow pale tip (sometimes paler grayish-white base of rectrices extensive enough to show beyond tail-coverts but is usually hidden). Fairly well-defined gray mantle (back and scapulars only) acquired by first winter (Basic I), accompanied by slight paling to underparts and grayish-pink base to bill, which usually shows distinct blackish tip (distal third or so). Legs and feet grayish pink.

Juvenile and Basic I European Common Gulls differ from Short-billed Gull in having sharply defined narrow blackish band at tip of white tail, rump, and uppertail coverts, the latter at most sparsely spotted or barred with dark markings; sparse but distinct brownish tips on the whitish underwing coverts; and generally whiter belly with scattered barring and spotting (especially on sides). Kamchatka Gull from northeast Asia is most similar to European birds in pattern, although more heavily patterned with relatively coarse, blackish marks and bars on rump and uppertail coverts, more extensively dark tail showing dusky margins to outer webs of rectrices extending basally on dorsal surface (underside appears more distinctly banded, as on European birds); northeast Asian birds also show distinct, though more extensive, dark tips to pale underwing coverts creating a coarsely marked pattern, and more extensively barred and spotted belly. All Eurasian birds in these plumages show a vague dark bar across secondaries and dark outer primaries from below, unlike Short-billed Gull, which lack this bar and are pale silvery gray across underside of remiges except for tips of primaries. Additionally, all Eurasian birds in Juvenile plumage show a pale-whitish area around base of bill and forehead, this area typically streaked brownish on Short-billed Gull; forehead becomes progressively whiter with molt to Basic I, but Eurasian birds usually paler still. First-winter (L. c. kamtschatschensis) has a broader black tailband and second winter has browner upperwing-coverts, a much darker underwing, and a trace of tailband, unlike (L. c. canus).

Separation of Common Gull from Ring-billed Gull (L. delawarensis) is a frequent identification problem. Adult Ring-billed averages slightly larger, with more robust build and has only a narrow white tertial-crescent, paler gray upperparts (beware some European Common Gulls may approach pale gray of Ring-billed), and thicker bill that is rather parallel-sided (profile along culmen and lower mandible) and that has a distinct black subterminal band. Most adult Ring-billed Gulls have quite pale-yellow eyes (Common Gull generally has darker eye, except northeast Asian birds); head finely spotted and streaked on Definitive Basic Ring-billed (Short-billed Gull heavily and diffusely mottled on head and neck in Basic plumage, but Eurasian Common Gull is patterned with sparse fine spots and streaks, like Ring-billed). In flight, large white patch formed by 2 large "mirrors" on Common Gull also distinctive from smaller white spots on Ring-billed Gull. Juvenile and Basic I Ring-billed Gulls differ most distinctly from Common Gull in usually showing a variegated tail pattern often with multiple broken bands basal to a broader dark subterminal band (Common Gull has a rather sharply defined dark subterminal band and white tail to rump, a pattern rarely exhibited by Ring-billed). By Basic I, Common Gull typically shows well-defined gray saddle (back and scapulars), whereas Ring-billed often has brownish markings in outer scapulars, disrupting saddle. Common Gull has lesser and median wing coverts more muted grayish brown with less contrasting, rounded brownish internal markings, while Ring-billed shows more strongly contrasting pattern in wing coverts, especially paler panel across greater coverts and prominent arrowhead-shaped and pointed internal pattern on lesser- and median coverts (latter pattern difficult to assess, especially if coverts worn or observer at some distance). In flight, Short-billed Gulls lack contrasting dark bar across secondaries from below shown by first-year Ring-billed, while Common Gulls are like Ring-billed in this trait. 

 

The Common Gull is currently an accidental migrant vagrant in British Columbia with 5 photographed provincial records. The first record was of a 2nd cycle bird found and photographed by Don Cecile found at the Head of the Lake, Vernon on March 29, 2003 (D. Cecile Pers. Comm.). Photographs of this bird were sent to gull experts and the identification was confirmed (D. Cecile Pers. Comm.). The second record was of an adult winter plumaged bird found on the turf farm at 72nd loafing with other gulls by Rick Toochin on January 28, 2004 (R. Toochin Pers. Comm.). Photographs of this bird were sent to gull experts and the identification was confirmed. The third record was of a very dark “Mew” Gull that was found and photographed by Mike Ashbee as it flew along the shoreline of Qualicum Beach on February 1, 2009 (M. Ashbee Pers. Comm.). The fourth record for the province was an adult in winter plumage found and photographed by Rick Toochin at the end of Potter Road in Sumas Prairie on February 19, 2016 (R. Toochin Pers. Comm.). Another bird, or possibly the same bird was found and photographed by Rick Toochin in a field at the corner of Vye Road and McDermott Road in Sumas Prairie on April 16, 2016 (R. Toochin Pers. Comm.). This bird was in the company of many species including Short-billed Gulls and stood out as larger, darker mantled, and larger billed (R. Toochin Pers. Comm.). 

 

With the recent split of Common Gull from Short-billed Gull, it is very likely keen observers will be looking harder for vagrant Common Gulls across British Columbia. It is highly likely that the odd vagrant Common “Kamchatka” Gull does occur along the west coast and at inland sites in British Columbia. The number of Short-billed Gulls found on the coast in the winter of British Columbia makes detection harder; while detection at inland areas in the winter months might be much easier as Short-billed Gulls vary in abundance at inland regions during the winter months (D. Cecile Pers. Comm.). During migration periods when Short-billed Gulls move through both coastal and inland regions, scrutiny of Short-billed Gulls will be required including excellent photographs taken of any suspected Common “Kamchatka” Gulls too document future records. As with any unusual gull learning the plumages of the common gull species first is critical before trying to find any out of place species. As stated earlier, the Common “Kamchatka” Gull is larger than the Short-billed Gull, with a much darker mantle and has a larger, longer yellow bill which should help alert keep observers to the bird’s presence. This form of the Common Gull likely can turn up anywhere in the province and should be looked for carefully. It is very likely given the increased number of records on the east coast of North America, where Short-billed Gulls are a rarity and any detected bird is given much greater scrutiny, that Common Gull will again occur in the future in the province. 

1.(1) 2nd cycle March 29, 2003: Don Cecile (photo) end of the Lake, Vernon (D. Cecile Pers. Comm.)

2.(1) adult winter plumage January 28, 2004: Rick Toochin (photo) Turf Farm, 72nd Street, Delta (R. Toochin Pers. Comm.)

3.(1) 2nd cycle October 28-29, 2007: Rick Toochin, mobs (photo) Jordan River (R. Toochin Pers. Comm.)

4.(1) adult winter plumage February 1, 2009: Mike Ashbee (photo) Qualicum Beach (M. Ashbee Pers. Comm.)

5.(1) adult winter plumage February 3, 2016: Rick Toochin (distant photo) Potter Road, Sumas Prairie (R. Toochin Pers. Comm.)

    (1) adult transition into breeding April 5, 2016: Rick Toochin (photo) Vye Road and McDermott Road, Sumas Prairie [likely same bird as above] (R. Toochin Pers. Comm.)

 

I want to thank Barb McKee for editing the original manuscript. All photos are used with permission of the photographer and are fully protected by copyright law. Photographs are not to be reproduced, published, or retransmitted on any website without the authorization of the photographer.

 

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