Yellow-legged Gull Larus michahellis Scientific name definitions

52–58 cm; 420–1600 g (all subspecies), 670–1150 g (lusitanius) (1 Galarza, A., J. Hidalgo, G. Ocio, and P. Rodriguez (2008). Sexual size dimorphism and determination of sex in Atlantic Yellow-legged Gulls Larus michahellis lusitanius from northern Spain. Ardeola 55(1):41–47. Close ); wingspan 120–140 cm. Generally more powerful, elegant  and deep-breasted than L. argentatus, with larger head , more bulbous forehead, flatter crown, fuller neck and stronger and blunter bill . Male is larger than female (2 Bosch, M. (1996). Sexual size dimorphism and determination of sex in Yellow-legged Gulls. Journal of Field Ornithology 67(4):534–541. Close ), in so-called lusitanius having larger head length, bill depth, bill length and body mass (1 Galarza, A., J. Hidalgo, G. Ocio, and P. Rodriguez (2008). Sexual size dimorphism and determination of sex in Atlantic Yellow-legged Gulls Larus michahellis lusitanius from northern Spain. Ardeola 55(1):41–47. Close ). Adult summer has white head , with red orbital ring, yellow bill with extensive red gonys spot that reaches upper mandible (unlike L. argentatus) and bright yellow legs. In some populations (NW Spain), however, 5–10% of birds have pink or partly pink legs, despite claim that yellow leg colour is a universal characteristic. Compared to L. argentatus, adult winter has slightly darker grey upperparts (lacking bluish tinge), more black on wingtips  with narrower white tips to primaries and white mirror on p10, less brown head markings than those L. argentatus with yellow legs; legs and feet are duller yellow at this season.

Juvenile is greyish brown with whitish face and dark mask , brown-mottled breast and flanks, contrasting with pale belly and central undertail-coverts, pale-fringed dark brown mantle, scapulars and tertials, inner greater coverts distinctly barred becoming gradually darker outwards, black bill and pale pinkish-colored legs and feet. First-year can acquire even more obvious but more restricted mask within overall paler head, very dark tertials, but less obviously patterned upperparts, marginally paler underparts and sometimes a slight pale base to the bill. Second-year gradually acquires grey mantle, but wings remain largely brown except blackish primaries and rounder white tips; legs and feet start to acquire yellowish tinge, but bill remains largely dark. Third-year is similar to adult, but has more extensive dark markings on bill, often with some dark markings on tertials and indistinct pale primary tips, as well as trace of dark tailband and markings on bill; legs paler yellow. Fourth-winter is basically like adult at same season, but has even paler legs and still has some dark markings on primary-coverts, tail and bill.

Race <em>atlantis</em> differs from nominate in being dark slate above  (as dark as L. fuscus graellsi, at least in adult, juvenile  and first-year plumages), as well as being on average smaller and more compact (e.g. wings and legs relatively shorter), with squarer head, often flat forehead and a stockier bill  (also defined by a generally longer gonys angle and shorter but deeper nostrils); in winter  has more obviously and extensively dark-spotted head than nominate. Within nominate race, some structural differences vary geographically, e.g. birds from Iberia/N Africa are generally smaller with flatter forehead and shorter legs, while birds in E of range often have a slenderer bill approaching L. cachinnans. Hybrids between nominate race and L. argentatus reported in Belgium, France, Spain, The Netherlands and UK (and the two have been observed courtship feeding in Spain), and with L. fuscus in Belgium, France, Iberia, Germany, Netherlands (3 Cottaar, F., and K. Verbeek (1994). Geelpootmeeuw gepaard met Kleine Mantelmeeuw broedend te IJmuiden. Dutch Birding 16(6):231–232. Close ) and UK, while mixed pairs with L. dominicanus have been observed in Mauritania, with L. cachinnans in S Poland, and mixed pairs with L. armenicus have been reported inland in Turkey.

Editor's Note: This article requires further editing work to merge existing content into the appropriate Subspecies sections. Please bear with us while this update takes place.

• Caspian x Yellow-legged Gull (hybrid) Larus cachinnans x michahellis
• Yellow-legged x Great Black-backed Gull (hybrid) Larus michahellis x marinus
• Yellow-legged x Lesser Black-backed Gull (hybrid) Larus michahellis x fuscus

Editor's Note: Additional distribution information for this taxon can be found in the 'Subspecies' article above. In the future we will develop a range-wide distribution article.

Coasts and inland habitats, being recorded breeding to > 2000 m in France (7 Leroy, T. (2008). Nidification réussie du Goéland leucophée Larus michahellis à 1186 m en Auvergne [Breeding of Yellow-legged Gull in Auvergne]. Ornithos 15(3):226–228. Close ). In W Europe, largely confined to coastal regions , but locally also rivers and inland lakes; also feeds at rubbish dumps, fields, and various other terrestrial habitats. Breeding in the Iberian Peninsula is overwhelmingly coastal; inland nesting was first reported in Catalonia in the early 1980s and remains rare and localised, chiefly involving a few pairs nesting beside lakes and reservoirs (8 Molina, B., Editor (2009). Gaviotas reidora, sombría y patiamarilla en España. Población en 2007–2009 y método de censo. SEO/Birdlife Monograph 27. SEO/Birdlife, Madrid, Spain. Close ). Breeds on rocky and sandy islands, beaches, cliffs, spits and grassy or shrubby river islands; also locally on rooftops. Around Black and Aegean Seas nests mainly on islands, ranging from barren to well vegetated, but in this region where the species overlaps with L. cachinnans at this season, it is the present species alone that breeds on cliff tops and roofs of buildings, with cachinnans favouring low-lying islets in shallow lagoons (9 Neubauer, G., M. Faber, and M. Zagalska-Neubauer (2010). Yellow-legged Gull in Poland: status and separation from yellow-legged Herring Gull and hybrids. Dutch Birding 32(3):163–170. Close ). However, further W, in S & SE Poland, the two species share the same breeding habitats (9 Neubauer, G., M. Faber, and M. Zagalska-Neubauer (2010). Yellow-legged Gull in Poland: status and separation from yellow-legged Herring Gull and hybrids. Dutch Birding 32(3):163–170. Close ), and in Germany michahellis mainly breeds in man-made habitats such as barrages and harbour installations (10 Gedeon, K., C. Grüneberg, A. Mitschke, C. Sudfeldt, W. Eikhorst, S. Fischer, M. Flade, S. Frick, I. Geiersberger, B. Koop, M. Kramer, T. Krüger, N. Roth, T. Ryslavy, S. Stübing, S. R. Sudmann, S. Steffens, F. Vökler, and K. Witt (2014). Atlas Deutscher Brutvogelarten [Atlas of German Breeding Birds]. Stiftung Vogelmonitoring Deutschland und Dachverband Deutscher Avifaunisten, Münster, Germany. Close ).

Sedentary and dispersive, but some populations at least are at least partially migratory, moving N in late summer / autumn, but mainly returning S in midwinter. W Mediterranean populations considered to be largely sedentary or dispersive, at most moving to Atlantic coasts with recent evidence from colour ringing that large numbers move to Bay of Biscay in non-breeding season (11 van den Berg, A. B., and M. Haas (2012). WP reports. Dutch Birding 34(4):255–265. Close ) and Atlantic populations (lusitanius) themselves rarely moving 100 km from their colonies (12 Munilla, A. (1997). Desplazamientos de la Gaviota Patiamarilla Larus cachinnans en poblaciones del norte de la península Ibérica. Ardeola 44(1):19–26. Close , 13 Arizaga, J., A. Aldalur, A. Herrero, J. F. Cuadrado, E. Díez, and A. Crespo (2014). Foraging distances of a resident yellow-legged gull (Larus michahellis) population in relation to refuse management on a local scale. European Journal of Wildlife Research 60(2):171–175. Close ) (in one study 69·2% of gulls were observed < 50 km from their natal colonies) (14 Arizaga, J., A. Herrero, A. Galarza, A., J. Hidalgo, A. Aldalur, J. F. Cuadrado, and G. Ocio (2010). First-year movements of Yellow-legged Gull (Larus michahellis lusitanius) from the southeastern Bay of Biscay. Waterbirds 33(4):444–450. Close ), while Balkan populations are apparently also mainly resident, although at least some move N as far as R Danube. However, SW European, Adriatic and at least some E Mediterranean populations disperse N post-breeding (Adriatic birds recorded moving almost 2000 km) (15 Kralj, J., S. Barišić, D. Ćiković, V. Tutiš, and N. D. van Swelm (2014). Extensive post-breeding movements of Adriatic Yellow-legged Gulls Larus michahellis. Journal of Ornithology 155(2):399–409. Close ), with numbers (apparently increasing, at least locally) reaching N, W & C Europe; earliest individuals in C Europe are typically young birds, as early as Apr, with adults appearing from May and the largest numbers (all ages) from July, becoming the most numerous large white-headed gull in this region until Sept (e.g. up to 10,000 on L Geneva, Switzerland) (16 Schuster, S. (2004). Die Einnischung einer neuen Vogelart am Bodensee: die Weisskopfmöwe Larus cachinnans [The niche of a new bird at Lake Constance: the Yellow-legged Gull Larus cachinnans]. Ornithologische Beobachtungen 101:115–124. Close ), but departure occurs from Aug and by early Nov few remain, spreading to W European, British and Baltic coasts, N to Denmark (mainly in E of country) and S Sweden (where > 200 records by 2001), for example, in England, mainly S, first individuals (adults) arrive in mid Jun, then first-years from early Aug, with peak numbers gathering between late Aug and mid Oct, declining from late Oct and most have gone by Dec, with a similar pattern being observed on nearby coasts of continental Europe, although very small numbers are recorded year-round in Netherlands, the species overwinters in very small numbers in Denmark and reasonable numbers remain in Germany at this season (especially in Neidersachsen and Nordrhein-Westphalia). Movements away from N African colonies less well known, but gulls at E Algerian colonies move N to E Spain and overland to Bay of Biscay, while juveniles from W colonies move N to Alborán Sea and Cádiz Bay, and return to N Africa in late autumn/winter (17 Baaloudj, A., F. Samraoui, A. Laouar, M. Benoughidene, D. Hasni, I. Bouchahdane, H. Khaled, S. Bensouilah, A. H. Alfarhan, and B. Samraoui (2011). Dispersal of Yellow-legged Gulls Larus michahellis ringed in Algeria: a preliminary analysis. Ardeola 59(1):137–144. Close ). Increasing numbers in NW Europe appear to be closely correlated with expansion N along French coast, e.g. first UK record was in 1971.

Elsewhere, apparent examples of this species have been observed in Red Sea, even as far S as Yemen, but confirmation of this is required, and such dispersal is surely rare. Nominate race is vagrant to Norway, Finland and Iceland, and has even been claimed as far S as The Gambia (18 Crewe, M. D. (2001). Selected observations from The Gambia, 1997–1999, with comments on the identification of a number of species. Bulletin of the African Bird Club 8(2):113–116. Close ), while race atlantis is known to wander to North America, where recorded in E Canada and E USA S to North Carolina, as well as N to Britain and Ireland, and also moves S at least to Cape Verdes, and perhaps also coasts of W Africa, where birds showing at least some characters of this subspecies have been observed between Senegambia and Nigeria.

Mostly fish, invertebrates , mammals (e.g. rats), refuse , scraps, offal, bird eggs and chicks (e.g. Monteiro’s Storm-petrels Hydrobates monteiroi and Audubon’s Shearwaters Puffinus lherminieri baroli in Azores (19 Monteiro, L. R., J. A. Ramos, R. W. Furness, and A. J. del Nevo, (1996). Movements, morphology, breeding, molt, diet and feeding of seabirds in the Azores. Colonial Waterbirds 19(1):82–97. Close ), White-faced Storm-petrels Pelagodroma marina and the endemic land snail Theba macandrewiana (20 Matias, R., and P. Catry (2010). The diet of Atlantic Yellow-legged Gulls (Larus michahellis atlantis) at an oceanic seabird colony: estimating predatory impact upon breeding petrels. European Journal of Wildlife Research 56(6):861–869. Close ), and Common Terns Sterna hirundo in NE Spain) (21 Hernández-Matías, A., and X. Ruiz (2003). Predation on Common Tern eggs by the Yellow-legged Gull at the Ebro Delta. Scientia Marina 67(Supplement 2):95–101. Close ) and insects. Highly opportunistic, like other large white-headed gulls, taking all manner of, sometimes unexpected, prey, e.g. Common Swift (Apus apus) (22 Gory, G., and R. André (1997). Prédation du Martinet noir Apus apus par le Goéland leucophée Larus cachinnans. Alauda 65(2):197–198. Close ), Bar-tailed Godwit (Limosa lapponica), Razorbill (Alca torda) (23 Jourde, P. (2004). Capture d’une Barge rousse Limosa lapponica et d’un Pingouin torda Alca torda par un Goéland leucophée Larus michahellis [Predation of Bar-tailed Godwit and Razorbill by Yellow-Iegged Gull]. Ornithos 11(2):93–95. Close ), and Rubia fruticosa fruits in Canary Is (24 Nogales, M., F. M. Medina, V. Quilis, and M. González-Rodríguez (2001). Ecological and biogeographical implications of Yellow-Legged Gulls (Larus cachinnans Pallas) as seed dispersers of Rubia fruticosa Ait. (Rubiaceae) in the Canary Islands. Journal of Biogeography 28:1137–1145. Close ).

Off Morocco, breeding birds fed on refuse, fish, insects, molluscs and a lizard, but fed their chicks mainly fish, but when both trawlers and purse-seine boats operate epipelagic fish account for > 60% of dietary biomass, whereas when only trawlers operated they augmented their diet mainly with human waste from refuse dumps and predation on eggs and chicks of L. audouinii increased, especially during the holy lamb festival when neither fishery operated (25 González-Solís, J. (2003). Impact of fisheries on activity, diet and predatory interactions between yellow-legged and Audouin’s gulls breeding at the Chafarinas Islands. Scientia Marina 67(Supplement 2):83–88. Close ); in Spain, availability of fishery discards was found to be strongly correlated with breeding success (26 Oró, D., M. Bosch, and X. Ruiz (1995). Effects of trawl moratorium on the breeding parameters of the Yellow-legged Gull Larus cachinnans. Ibis 137(4):547–549. Close ). Shoals of swimming crabs and anchovies are important food sources during breeding season in Strait of Gibraltar and off NW Spain; in Galicia, Henslow’s swimming crab (Polybius henslowii) is second most important food item (after refuse) and is also a key item in Asturias (27 de Juana, E., and E. Garcia (2015). The Birds of the Iberian Peninsula. Bloomsbury, London, UK. Close , 28 Munilla, I. (1997). Henslow’s swimming crab (Polybius henslowii) as an important food for yellow-legged gulls (Larus cachinnans) in NW Spain. ICES Journal of Marine Science 54(4):631–634. Close ) and in C Portugal (29 Alonso, H., A. Almeida, J. P. Granadeiro, and P. Catry (2015). Temporal and age-related dietary variations in a large population of Yellow-legged Gulls Larus michahellis: implications for management and conservation. European Journal of Wildlife Research 61(6):819–829. Close ).

Exploits human intrusion at seabird colonies, seizing eggs when incubating birds flushed. Some adults obtain food mainly by following fishing boats and taking offal. On Selvagen Is (Madeira) flies inland to feed on grasshoppers and moths, and has been recorded feeding on African desert locusts (Schistocerca gregaria) in Morocco (30 Ullman, M. (2006). African Desert Locusts in Morocco in November 2004. British Birds 99(9):489–491. Close ); also terrestrial invertebrates, mostly Coleoptera and Orthoptera, are the most frequently consumed prey items (67%) at El Hierro, Canary Is, an oceanic island surrounded by deep waters (31 López, H., A. J. Pérez, B. Rumeu, and M. Nogales, (2016). Trophic strategies of Yellow-legged Gull Larus michahellis on oceanic islands surrounded by deep waters. Bird Study 63(3):337–345. Close ). Also kleptoparasitic on L. audouinii, particularly when fishing vessels not active, and even recorded seizing prey from Peregrine Falcons (Falco peregrinus) (32 Estrada-Devesa, V., J. Marti-Aledo, M. Boix, and J. Pibernat (1997). Peregrine Falcons (Falco peregrinus brookei) kleptoparasitised by Yellow-legged Gulls (Larus cachinnans). Ardeola 44(2):225–226. Close ).

Forages mostly by wading in intertidal zone, plunge-diving, and following ships; also follows plough. However, study of foraging behaviour (based on pellets) of birds at colonies on islands off SE France found that birds used three main areas—refuse dumps, terrestrial habitats and marine habitats—and that rubbish dumps were consistently used most (evidence in 53–74% of pellets), even when refuse dump accessibility was low, but that the majority of pellets contained materials from two simultaneous habitats (evidence in 50–64% of pellets) (33 Duhem, C., E. Vidal, J. Legrand, and T. Tatoni (2003). Opportunistic feeding responses of the Yellow-legged Gull Larus michahellis to accessibility of refuse dumps. Bird Study 50(1):61–67. Close ). In Iberia foraging remains overwhelmingly coastal or near-coastal in winter; inland sites, including rubbish dumps, attract only a few individuals: only 278 birds were found inland in Spain in Jan 2009 of a winter census total of 219,599 individuals (8 Molina, B., Editor (2009). Gaviotas reidora, sombría y patiamarilla en España. Población en 2007–2009 y método de censo. SEO/Birdlife Monograph 27. SEO/Birdlife, Madrid, Spain. Close ).

Considered most similar to L. fuscus, and rather deeper and hoarser than L. argentatus, e.g. woouw or grouuw, while breeding-season long-call comprises 14–25 elements, not 8–14 as in L. argentatus. Threat call is a repeated "ow-ow-ow" and the alarm call a repeated and drawn out "aaaaow".

Similar to L. argentatus. In some colonies, territorial throughout winter; lays from mid March or, for example in Atlantic Is, early April, with hatching in latter region from mid May (19 Monteiro, L. R., J. A. Ramos, R. W. Furness, and A. J. del Nevo, (1996). Movements, morphology, breeding, molt, diet and feeding of seabirds in the Azores. Colonial Waterbirds 19(1):82–97. Close ); exceptionally, young by late April in Mediterranean Turkey. Fledging at Gibraltar is from late June but chiefly in July. Colonies of up to c. 8000 pairs (Medes Is, NE Spain); forms monospecific clusters, even when nesting beside other gulls; sometimes on high ground, hundreds of metres from water. Nests preferentially close to or under bushes, sometimes in bushes or dense copses of osier (Cornus); nesting in tree forks occurs in Gibraltar (27 de Juana, E., and E. Garcia (2015). The Birds of the Iberian Peninsula. Bloomsbury, London, UK. Close ); also increasingly on rooftops in coastal cities, e.g. in Spain: especially in the north-west and Portugal (27 de Juana, E., and E. Garcia (2015). The Birds of the Iberian Peninsula. Bloomsbury, London, UK. Close ), and in Istanbul (Turkey). Density 20–140 nests/ha, usually a few metres apart.

Nest constructed (by both sexes) of nearby vegetation, feathers, debris and old carcasses; often builds or lines nest with eelgrass (Zostera marina). Single-brooded. Homosexual pairs (female only) have been recorded in Poland (9 Neubauer, G., M. Faber, and M. Zagalska-Neubauer (2010). Yellow-legged Gull in Poland: status and separation from yellow-legged Herring Gull and hybrids. Dutch Birding 32(3):163–170. Close ). Usually 2–3 eggs (1–4), size 64–71 mm × 44·5–49·5 mm (34 Perrin de Brichambaut, J. (1998). Sur le genre Larus nidifiant aux Açores. Alauda 66(4):306. Close ), laid at 2–3-day intervals, colour very variable, but generally much like that of L. argentatus; incubation averages 26–30 days, by both sexes, but mainly female, starting with first egg; chick similar to that of L. argentatus; hatching weight c. 60 g; swims at c. 10 days, when partly feathered; fledging c. 6–7 weeks. Hatching success 83% at an Azorean colony (race atlantis) (19 Monteiro, L. R., J. A. Ramos, R. W. Furness, and A. J. del Nevo, (1996). Movements, morphology, breeding, molt, diet and feeding of seabirds in the Azores. Colonial Waterbirds 19(1):82–97. Close ). In northern Spain, where populations have stabilised or are beginning to decline after a long period of rapid increase, fledging success is most closely associated with hatching date, earlier nests being most successful (35 Delgado, S., and J. Arizaga (2017). Pre-fledging survival in a Yellow-legged Gull Larus michahellis population in northern Iberia is mostly determined by hatching date. Bird Study 64(2):132–137. Close ).

Not globally threatened (Least Concern). Global population size unknown, but European population (the majority) estimated at 409,000–534,000 pairs and increasing, especially in France and the Iberian peninsula. The Iberian population in 2007–2008 was censused at 130,449 pairs, following at least three decades of rapid population increase (27 de Juana, E., and E. Garcia (2015). The Birds of the Iberian Peninsula. Bloomsbury, London, UK. Close ). In France the population numbered just 9000 pairs in 1970 but 25,000 pairs ten years later and 41,000 pairs by late 1990s (36 Cadiou, B., J.-M. Pons, P. Yésou, and le GISOM (2004). Les oiseaux marins nicheurs en France métropolitaine à la fin du XXe siècle. Ornithos 11(6):265–282. Close ) (of which c. 50% on Mediterranean coast), by which time had spread N to coastal Normandy and inland to Alsace (and started to nest in towns); elsewhere evidence of range expansion N, breeding in Netherlands (since 1994), inland in Poland, Austria (since 1987), Slovakia (since 1984), Poland (since 1995, where most pairs are mixed, with L. cachinnans) (9 Neubauer, G., M. Faber, and M. Zagalska-Neubauer (2010). Yellow-legged Gull in Poland: status and separation from yellow-legged Herring Gull and hybrids. Dutch Birding 32(3):163–170. Close ) and S England (since 1995, but numbers still tiny) (37 Holling, M., and The Rare Breeding Birds Panel (2011). Rare breeding birds in the United Kingdom in 2009. British Birds 104(9):476–537. Close , 38 Holling, M., and The Rare Breeding Birds Panel (2013). Rare breeding birds in the United Kingdom in 2011. British Birds 106(9):496–554. Close , 39 Holling, M., and The Rare Breeding Birds Panel (2014). Rare breeding birds in the United Kingdom in 2012. British Birds 107(9):504–560. Close , 40 Holling, M., and the Rare Breeding Birds Panel (2015). Rare breeding birds in the United Kingdom in 2013. British Birds 108(7):373–422. Close ). In Germany, first bred in 1977, and population most recently (2005–2009) estimated at 170–230 breeding pairs (10 Gedeon, K., C. Grüneberg, A. Mitschke, C. Sudfeldt, W. Eikhorst, S. Fischer, M. Flade, S. Frick, I. Geiersberger, B. Koop, M. Kramer, T. Krüger, N. Roth, T. Ryslavy, S. Stübing, S. R. Sudmann, S. Steffens, F. Vökler, and K. Witt (2014). Atlas Deutscher Brutvogelarten [Atlas of German Breeding Birds]. Stiftung Vogelmonitoring Deutschland und Dachverband Deutscher Avifaunisten, Münster, Germany. Close ). Other population estimates from late 1990s: 119,200–139,200 pairs in Iberia including Balearics (including c. 13,500 pairs on Medes Is) (41 Bosch, M., and D. Sol (1996). Daily activity patterns in breeding Yellow-legged Gulls (Larus cachinnans). Ardeola 43(1):97–101. Close ), 40,000–50,000 pairs in Italy (with 8750 and 4767 pairs in Sardinia and Sicily, respectively, and evidence of recent spread), 30,000 pairs in Croatia, 15,000 pairs in Greece, 4274 pairs in Bulgaria (in 1992), 6325 pairs in Morocco, 2500 pairs in Algeria (where inland and urban breeding have been recorded, and local increases reported) (42 Moulaï, R., N. Sadoul, and S. Doumandj (2005). Nidification urbaine et à l’intérieur des terres du Goéland leucophée Larus michahellis en Algérie. Alauda 73(3):195–200. Close , 43 Moulaï, R., N. Sadoul, and S. Doumandj (2006). Effectifs et biologie de la reproduction du Goéland leucophée Larus michahellis dans la région de Béjaia (Algérie). Alauda 74(2):225–234. Close ) and 600–700 pairs in Tunisia; at this time, other populations of the species were apparently either small (e.g. 250 pairs inland in L Neuchatel, Germany/Switzerland), or insufficiently known, but in Turkey there was at least 3000–5000 pairs in Istanbul and another c. 3000 pairs in Sea of Marmara; discovered breeding in Lebanon in mid 1990s (44 Ramadan-Jaradi, G., and M. Ramadan-Jaradi (1997). Notes on some breeding birds in Lebanon. Sandgrouse 19(2):122–125. Close ). On Chafarinas Is (off NE Morocco) one colony increased from 250 pairs in 1976 to 850 pairs in 1985, while a second totalled 3000 pairs. Winter population estimates: 230,000 birds in Iberia, 123,000 in France (of which 95% in Mediterranean), 60,000–100,000 in Italy and 12,000 in Algeria, as well as 100,000–120,000 individuals of both this species and L. cachinnans in Turkey (the majority of which were thought to be the present species, although this issue probably requires further evaluation).

Race atlantis estimated to number just 2800 pairs (or 6415 individuals) (45 Monteiro, L. R., J. A. Ramos, and R. W. Furness, (1996). Past and present status and conservation of the seabirds breeding in the Azores archipelago. Biological Conservation 78:319–328. Close ) on Azores—to which some authorities restrict this taxon—where largest colonies on Ilhéus das Cabras, off Terceira (400 pairs), Ilhéu do Topo, off São Jorge (300 pairs) and at Lagoa do Fogo, on São Miguel (250 pairs), but 6000 pairs on Madeira and 4000–4700 pairs of gulls on Canary Is (most on La Gomera and Gran Canaria) are also usually also attributed to this taxon.

Threats include oil pollution and (largely in the past) general persecution. Habitat destruction and tourist disturbance affects breeding sites in Spain, while many colonies are regularly subject to harvesting of eggs by local communities. Species has been culled (adults shot and nests destroyed) in cities with rooftop populations and, in the Spanish Mediterranean and Black Sea, to prevent predation on Larus melanocephalus  and to protect Larus audouinii , while species is poisoned to reduce predation on White-faced Storm-petrel (Pelagodroma marina ) in Macaronesia (see also Food and feeding) BirdLife International (2015) Species factsheet: Larus michahellis. Downloaded from http://www.birdlife.org on 22/06/2015. .