This species occurs in a wide variety of habitats, mainly in deserts, semi-deserts and on arid mountains. It is often found near remote habitations and camps, villages and livestock enclosures (Aspinall and Porter 2011). It is omnivorous, but feeds mainly on carrion, invertebrates, young birds and eggs, and food scraps (Jennings 2010). Individuals often concentrate along roads to take advantage of the high food availability like spilt grain, road kill and rubbish (Jennings 2010). The species can survive for long periods without drinking water (Jennings 2010). Breeding pairs form in November, and nesting commences by February (Jennings 2010). The nest is typically placed high up in a tree, preferably acacia, date palm or mangrove, or occasionally on rocks and cliffs, pylons or tall towers (Jennings 2010). The nest is made of twigs, cloths and plastic, lined with soft goat and camel hair, wool, down, grasses, feathers and cloths (Jennings 2010). Nests may be used over several years, or dismantled to provide material for a new nest (Jennings 2010). Eggs are laid in February/March; the clutch size is variable and depends on food availability (Jennings 2010). After the breeding season in early summer, individuals abandon the breeding areas in the arid regions and form large flocks until late autumn (Jennings 2010).

This species is marine; it occurs in offshore waters, but also closer to the shore near breeding colonies (Aspinall and Porter 2011, del Hoyo et al. 2019). Its diet consists of fish, squid and crustaceans, which are caught by plunge-diving, pursuits and surface-seizing (del Hoyo et al. 2019). It breeds on cliffs and slopes on barely vegetated, rocky offshore islands. There is not much known about its breeding biology; it presumably breeds during summer. While adult individuals are thought to be largely sedentary, immature birds disperse into the Gulf of Oman and occasionally into the Arabian Gulf (del Hoyo et al. 2019).

This species inhabits any kind of wetland, from open, sandy coasts and lagoons to sheltered creeks, ponds, lakes, reservoirs, sewage treatment plants and ornamental ponds in cities (Richardson 1990, Jennings 2010, Aspinall and Porter 2011). It is an opportunistic feeder; it takes predominantly fish, but also insects, reptiles and small birds (Jennings 2010). It occasionally establishes feeding territories, where it hunts by stalking or standing still to wait for prey (Jennings 2010). It feeds at any time of the day or at night, but is most active at dawn or dusk, typically roosting communally or solitary during the middle of the day and at night (Brown et al. 1982, Kushlan and Hancock 2005). The species is migratory. Individuals wintering in or migrating through the UAE breed during spring in Siberia, where they may form large colonies (Kushlan and Hancock 2005, Jennings 2010). Most migratory movements occur nocturnally in small parties or larger flocks of 200 to 250 individuals (Brown et al. 1982).

This species is very rarely observed in coastal waters (Jennings 2010, Aspinall and Porter 2011). At sea, it is often associated with patches of macroalgae (e.g. Sargassum spp.) or flotsam which it uses for perching (del Hoyo et al. 1996, Haney et al. 1999, Jennings 2010). Its diet consists predominantly of squid and surface-schooling fish less than 6 cm long as well as crustaceans and occasionally aquatic insects or molluscs (del Hoyo et al. 1996, Higgins and Davies 1996, Jennings 2010). During the breeding season from April to July, the species forms colonies on rocky or sandy islands and on the mainland coast, where enough low vegetation is present (Jennings 2010, Aspinall and Porter 2011). When nesting, the species often associates with nesting White-cheeked Tern Sterna repressa or Lesser Crested Tern Thalasseus bengalensis (Jennings 2010). One single egg is laid directly on the ground, in a small scrape or depression in shingle or sand (Higgins and Davies 1996, Jennings 2010). Nests are placed in concealed locations and always in the shade, like under a bush, in a rock crevice or on a ledge (Jennings 2010). The species is migratory and dispersive; it abandons its breeding site at the end of the breeding season to overwinter at sea (Higgins and Davies 1996, Haney et al. 1999). Its detailed migratory movements are largely unknown however (del Hoyo et al. 1996), but it is assumed that the Arabian population winters in the Indian Ocean east of Africa (Jennings 2010). Away from the breeding grounds, the species is entirely pelagic (del Hoyo et al. 1996, Haney et al. 1999).

This species is found along the coast and in inland wetlands (Aspinall and Porter 2011). It winters on sheltered coastal waters, estuaries and along large rivers, occupying harbours, jetties, piers, beaches and coastal wetlands including lagoons, rivers, lakes, swamps and saltworks, mangroves and saltmarshes (del Hoyo et al. 1996, Higgins and Davies 1996). During this season, it roosts on unvegetated sandy beaches, shores of estuaries or lagoons, sandbars and rocky shores (Higgins and Davies 1996). There is no information available about its diet in the UAE; elsewhere the species is opportunistic, its diet consisting predominantly of small fish and occasionally planktonic crustaceans and insects (del Hoyo et al. 1996). It forages in flocks over freshwater as well as marine habitats, and often follows predatory fish, waiting for panicking baitfish to surface. It is gregarious throughout the year (Snow and Perrins 1998). The species is strongly migratory (del Hoyo et al. 1996, Snow and Perrins 1998). It breeds between April and June in solitary pairs or colonially in groups (of up to several thousand pairs in central Asia) (del Hoyo et al. 1996). Individuals migrate south after breeding between August and October, returning to the breeding grounds in March or April (del Hoyo et al. 1996).

This species inhabits coastal waters (Aspinall and Porter 2011). It is gregarious throughout the year, foraging in single- or mixed-species flocks up to 400 individuals (del Hoyo et al. 1996, Snow and Perrins 1998). It forages in the surf and offshore waters by plunge-diving or surface-dipping (del Hoyo et al. 1996, Snow and Perrins 1998, Jennings 2010). Its diet consists predominantly of small pelagic fish, but it may also take crustaceans such as prawns and shrimps (Urban et al. 1986, del Hoyo et al. 1996, Jennings 2010). During the breeding season, it establishes large, densely packed colonies on sandy patches on islands up to 200 m from the coast (Jennings 2010, Aspinall and Porter 2011). Colony locations are often protected by low vegetation and shrubs from predators, e.g. introduced cats and dogs, mice or Sooty Gull Larus hemprichii (Jennings 2010). The breeding season lasts from early May to July (Jennings 2010). The nest is a shallow scrape in the sand, which may gradually get deeper during incubation (Jennings 2010). Clutches contain one egg (Jennings 2010). After the breeding season, the species disperses out into the Indian Ocean; the details of its movement are poorly known (del Hoyo et al. 1996, Jennings 2010).

During the non-breeding season, this species is almost entirely coastal, frequenting shallow inshore waters and mudflats further inland (del Hoyo et al. 1996, Aspinall and Porter 2011). It forages in shallow water close to the shore and on sandy beaches, but also inland in flooded saltflats (Jennings 2010). It mainly feeds on small fish and marine invertebrates, which it takes by plunge-diving, surface-dipping or by wading in shallow pools (Jennings 2010). Individuals may oversummer in the UAE; however, they do not breed there. Instead, migratory populations breed in central Asia (Jennings 2010)

During the non-breeding season, this species is most common in coastal habitats and tidal inshore waters, showing a preference for inlets or estuaries with sandy or muddy beaches, and generally avoiding rocky or exposed coastlines (del Hoyo et al. 1996, Snow and Perrins 1998, Aspinall and Porter 2011). It may also occur inland during this season, frequenting ploughed fields, moist grasslands, urban parks, sewage treatment plants, refuse tips, reservoirs, ponds and ornamental waters, and roosts on sandy and gravel sites or on inland reservoirs (Richards 1990, Snow and Perrins 1998, Aspinall and Porter 2011). There is no information available about its diet in the UAE; elsewhere, it feeds predominantly of aquatic and terrestrial insects, earthworms and marine invertebrates, although it may also take fish, rodents and agricultural grain (Flint et al. 1984, del Hoyo et al. 1996). The species generally remains gregarious throughout the year and may roost in large flocks during the winter (Richards 1990). The species breeds between April and May in Eurasia, where it forms dense colonies of up to several thousand pairs (del Hoyo et al. 1996, Snow and Perrins 1998). ;

This species's ecology and habitat requirements in the UAE are not well known; thus the following information refers to its global distribution range during the non-breeding season. The species inhabits inshore and offshore seas and islands, as well as lagoons, estuaries and harbours (Richardson 1990, Snow and Perrins 1998). Less frequently, it may also occur in inland habitats, such as large lakes and rivers (Urban;et al. 1986, Richardson 1990, Snow and Perrins 1998). It is often seen foraging in large flocks on arable land, pasture land, and on refuse dumps (Richards 1990, del Hoyo et al. 1996). The species is an omnivorous, opportunistic feeder that forages extensively at sea. Its diet consists of small fish, aquatic and terrestrial invertebrates, bird eggs and nestlings, carrion, offal, rodents, berries;and grain (Urban et al. 1986, del Hoyo;et al.;1996, BirdLife International 2000, Olsen and Larsson 2003). It often follows fishing fleets, feeding on discarded bycatch (BirdLife International 2000). Outside of the breeding season, the species is gregarious. The species is migratory and travels with many stopovers from its wintering grounds to the breeding grounds in northern Eurasia (del Hoyo;et al.;1996, Olsen and Larsson 2003). It breeds colonially, often with other gull species, in colonies ranging in size from a few pairs to several tens of thousands (Richards 1990, Snow and Perrins 1998,;Mitchell;et al.;2004).

This species inhabits open country inland, usually near waterbodies (Jennings 2010, Aspinall and Porter 2011). It is found close to pools of fresh or brackish water, like ditches, water treatment plants, sewage dumps, reservoirs, pits, pools, wet wadis, as well as newly formed and temporary waterbodies (Richardson 1990, Jennings 2010). It also frequents irrigated land, agricultural areas and grass or meadows, including large gardens, golf courses and camel race tracks (Jennings 2010, Aspinall and Porter 2011). There is no information available about its diet in the UAE or Arabia; elsewhere it takes beetles and other insects, as well as molluscs, worms and crustaceans. It mainly forages around dusk and dawn and at night (Jennings 2010). The breeding period starts in February, with most clutches reported between April and May. The species is territorial. Even though it may nest in groups at the same site, it is not colonial (Jennings 2010). The nest is a shallow scrape, unlined or lined with small stones and debris, usually situated near water. Clutches contain usually four eggs; however, as eggs and chicks suffer high mortality, possibly due to predation by House Crow Corvus splendens, mostly only one or two chicks fledge (Jennings 2010).