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Disko Bay

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Disko Bay ( Greenlandic : Qeqertarsuup tunua ; Danish : Diskobugten ) is a large bay on the western coast of Greenland . The bay constitutes a wide southeastern inlet of Baffin Bay .

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51-476: To the south the coastline is complicated with multiple waterways of skerries and small islands in the Aasiaat archipelago. Qasigiannguit and Ilimanaq are the main settlements in the southeastern inlet, just south of the outflow of Ilulissat Icefjord . From the north the bay is bounded by Qeqertarsuaq (Disko Island) , the largest island on the western coast. North of Ilulissat and west of Alluttoq Island

102-450: A behaviour seen in other animal species, such as elephants, wolves, and the fathead minnow . Lasting between 22 and 26 days, incubation begins after the first egg is laid but is not continuous until after the second egg is laid, meaning that the first two chicks hatch at about the same time, and the third some time later. Young chicks are brooded by their parents for about one or two weeks, and often at least one parent stays behind to guard

153-495: A few species do live on islands such as the Galapagos and New Caledonia . Many species breed in coastal colonies, with a preference for islands, and one species, the grey gull , breeds in the interior of dry deserts far from water. Considerable variety exists in the family and species may breed and feed in marine, freshwater, or terrestrial habitats. Most gull species are migratory , with birds moving to warmer habitats during

204-498: A higher level of synchronisation in larger colonies. The eggs of gulls are usually dark tan to brown or dark olive with dark splotches and scrawl markings, and they are well camouflaged. Both sexes incubate the eggs; incubation bouts last between one and four hours during the day, and one parent incubates through the night. Research on various bird species, including gulls, suggests that females form pair bonds with other females to obtain alloparental care for their dependent offspring,

255-521: A highly developed social structure. For example, many gull colonies display mobbing behaviour, attacking and harassing predators and other intruders. Certain species, such as the herring gull, have exhibited tool-use behaviour, for example using pieces of bread as bait with which to catch goldfish . Many species of gulls have learned to coexist successfully with humans and thrive in human habitats. Others rely on kleptoparasitism to get their food. Gulls have been observed preying on live whales, landing on

306-404: A maximum age of 49 years recorded for the herring gull . Gulls nest in large, densely packed, noisy colonies. They lay two or three speckled eggs in nests composed of vegetation. The young are precocial , born with dark mottled down and mobile upon hatching. Gulls are resourceful, inquisitive, and intelligent, the larger species in particular, demonstrating complex methods of communication and

357-534: A mixture of both natural prey and human refuse. The gulls relied substantially on the Henslow's swimming crab ( Polybius henslowii ). Yet, in times when local prey availability is low, the gulls shift to human-related food. These temporal shifts from a marine to terrestrial prey highlight the resilience adult gulls have and their ability to keep chick condition consistent. Human disturbance has also shown to have an effect on gull breeding, in which hatching failure

408-569: A number of years after the break-up. Gulls also display high levels of site fidelity , returning to the same colony after breeding there once and even usually breeding at the same location within that colony. Gull colonies can vary from just a few pairs to over a hundred thousand pairs, and may be exclusive to that gull species or shared with other seabird species. A few species nest singly, and single pairs of band-tailed gulls may breed in colonies of other bird species. Within colonies, gull pairs are territorial , defending an area of varying size around

459-410: A red spot for the larger white-headed species and red, dark red or black in the smaller species. Gulls are a generalist species that can thrive in various environments and survive on a widely varied diet. They are the least specialised of all the seabirds, and their morphology allows for equal adeptness in swimming, flying, and walking. They are more adept walking on land than most other seabirds, and

510-560: A suitable surface on which to drop shells, and apparently a learned component to the task exists, as older birds are more successful than younger ones. While overall feeding success is a function of age, the diversity in both prey and feeding methods is not. The time taken to learn foraging skills may explain the delayed maturation in gulls. Gulls have only a limited ability to dive below the water to feed on deeper prey. To obtain prey from deeper down, many species of gulls feed in association with other animals, where marine hunters drive prey to

561-427: Is a layperson's term and is not used by most ornithologists and biologists. The name is used informally to refer to a common local species (or all gulls in general) and has no fixed taxonomic meaning. In common usage, gull-like seabirds that are not technically gulls (e.g. albatrosses , fulmars , terns , and skuas ) may also be referred to as 'seagulls' by the layperson. The American Ornithologists' Union combines

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612-516: Is a list of the 54 gull species , presented in taxonomic sequence . The Laridae are known from not-yet-published fossil evidence since the Early Oligocene , some 30–33 million years ago. Three gull-like species were described by Alphonse Milne-Edwards from the early Miocene of Saint-Gérand-le-Puy, France. A fossil gull from the Middle to Late Miocene of Cherry County, Nebraska , US,

663-468: Is a single-prey specialist, and no gull species forages using only a single method. The type of food depends on circumstances, and terrestrial prey such as seeds, fruit, and earthworms are more common during the breeding season while marine prey is more common in the nonbreeding season when birds spend more time on large bodies of water. In addition to taking a wide range of prey, gulls display great versatility in how they obtain prey. Prey can be obtained in

714-426: Is an accepted version of this page 11, see below Gulls , or colloquially seagulls , are seabirds of the family Laridae in the suborder Lari . They are most closely related to terns and skimmers , distantly related to auks , and even more distantly related to waders . Until the 21st century, most gulls were placed in the genus Larus , but that arrangement is now considered polyphyletic , leading to

765-401: Is an important part of the pair-bonding process. Most gull nests are mats of herbaceous matter with a central nest cup. Nests are usually built on the ground, but a few species establish their nests on cliffs (the usual preference for kittiwakes), and some choose to nest in trees and high places (e.g. Bonaparte's gulls ). Species that nest in marshes need to construct a nesting platform to keep

816-594: Is changing, as the bay has been gradually warming up since 1997. It is uncertain when the Inuit first started venturing into Disko Bay, but the Saqqaq were present there between 2400 and 900 BC. Disko Bay has been an important location for centuries. Its coastline was first encountered by Europeans when Erik the Red started a settlement in 985 AD on the more habitable western coast of Greenland. The two settlements, called

867-423: Is darker varies from pale grey to black. A few species vary in this, the ivory gull is entirely white, and some like the lava gull and Heermann's gull have partly or entirely grey bodies. The wingtips of most species are black, which improves their resistance to wear and tear, usually with a diagnostic pattern of white markings. The head of a gull may be covered by a dark hood or be entirely white. The plumage of

918-1384: Is derived from the Old Norse sker , which means a small rocky island in the sea (which in turn derives from the Proto-Indo-European root * sker -, "cut", in the sense of a rock cut off from the land). The Old Norse term sker was brought into the English language via the Scots language word spelled skerrie or skerry . It is a cognate of the Scandinavian languages ' words for skerry – Icelandic , Faroese : sker , Danish : skær , Swedish : skär , Norwegian : skjær / skjer , found also in German : Schäre , Finnish : kari , Estonian : skäär , Latvian : šēra , Lithuanian : šcheras and Russian : шхеры ( shkhery ). In Scottish Gaelic , it appears as sgeir , e.g. Sula Sgeir , in Irish as sceir , in Welsh as sgeri , and in Manx as skeyr . Skerries are most commonly formed at

969-419: Is directly proportional to the amount of disturbance in a given plot. Certain gull breeds have been known to feast on the eyeballs of baby seals, and directly pilfer milk from the elephant seal 's teat. Gulls are monogamous and colonial breeders that display mate fidelity which normally lasts for the life of the pair. Divorce of mated pairs does occur, but it apparently has a social cost that persists for

1020-440: Is home during spring time to bowhead ( Balaena mysticetus ) and humpback ( Megaptera novaeangliae ) whales, as well as Pilot ( Globicephala melas ), killer whales ( Orcinus orca ) and narwhal ( Monodon monoceros ). On the shores, various birds can be found such as gulls , terns , eider ducks , guillemots , kittiwakes , cormorants and fulmars . Animals such as Arctic foxes , hares and ptarmigan can be found around

1071-464: Is questionable. Before the 21st century, most gulls were placed in the genus Larus , but this arrangement is now known to be polyphyletic , leading to the resurrection of the genera Ichthyaetus , Chroicocephalus , Leucophaeus , Saundersilarus , and Hydrocoloeus . Some English names refer to species complexes within the group: In common usage, members of various gull species are often referred to as 'sea gulls' or 'seagulls'; however, this

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1122-412: Is such a group of glacially formed skerries, called a skjærgård (sometimes translated into English as archipelago, but specifically one near the coast of the mainland). Many of the cross fjords are so arranged that they parallel the coast and provide a protected channel behind an almost unbroken succession of rocky islands and skerries. By this channel one can travel through a protected passage almost

1173-589: The Eastern and Western settlements , were sustenance economies that survived on animal husbandry and farming. Soon after the Western settlement was established, the Norsemen travelled up the coast during the summer thaw and discovered Disko Bay. Their interest in this bay was due to its rich resources: walruses for ivory , seals for their pelts, and whales for a variety of materials. These products became

1224-527: The Larus species. Live food often includes crustaceans , molluscs , fish and small birds. Gulls have unhinging jaws that provide the flexibility to consume large prey. Gulls are typically coastal or inland species, rarely venturing far out to sea, except for the kittiwakes and Sabine's gull . The large species take up to four years to attain full adult plumage, but two years is typical for small gulls. Large white-headed gulls are usually long-lived birds, with

1275-800: The Sternidae , Stercorariidae , and Rhynchopidae as subfamilies in the family Laridae, but early 21st-century research shows this to be incorrect. A molecular phylogenetic study published in 2022 found the following relationships between the genera, including the most recent generic change: the placement of Saunders's gull in its own genus Saundersilarus . Creagrus – swallow-tailed gull Hydrocoloeus – little gull Rhodostethia – Ross's gull Rissa – kittiwakes (2 species) Xema – Sabine's gull Pagophila – ivory gull Saundersilarus – Saunders's gull Chroicocephalus – (10 species) Leucophaeus – (5 species) Ichthyaetus – (6 species) Larus – (24 species) This

1326-817: The White Sea . The United Kingdom has a large number of skerries including Staple Island (an outer Farne Island ) in England; a small rocky outcrop near the Fowlsheugh in northeast Scotland; numerous reefs in the Hebrides such as Dubh Artach and Skerryvore ; and The Skerries , located off the Antrim coast of Northern Ireland. Skerries is the name of a coastal area of Dublin , Ireland, with many skerries offshore, including Rockabill , Shenick Island , Colt Island and St Patrick's Island . Gull This

1377-948: The Eastern settlement, which was below the Arctic Circle , became too cold for habitation. From that time until Danish colonization in the 18th century, the Inuit controlled the Disko Bay area although English and Dutch whalers sometimes visited the area after it was charted during John Davis 's third Greenland expedition in 1587. It is home to a wide range of species due to the nutrient-rich waters. This includes benthic and pelagic fish, such as capelin ( Mallotus villosus ) and cod ( Gadus morhua ). This attracts migratory seals such as harp ( Pagophilus groenlandicus ) and hooded seal ( Cystophora cristata ) and ringed ( Pusa hispida ) and bearded seal ( Erignathus barbatus ). The bay

1428-420: The air, on water, or on land. In the air, a number of hooded species are able to hawk insects on the wing; larger species perform this feat more rarely. Gulls on the wing also snatch items both off water and off the ground, and over water they also plunge-dive to catch prey. Again, smaller species are more manoeuvrable and better able to hover-dip fish from the air. Dipping is also common when birds are sitting on

1479-475: The bay transforms into Sullorsuaq Strait separating Qeqertarsuaq from Nuussuaq Peninsula . It is the largest open bay in western Greenland, measuring 150 kilometres (93 mi) north to south and 100 kilometres (62 mi) east to west. It has an average depth of 400 metres (1,300 ft) and average water temperature of 3.5 °C (38.3 °F), which in winter drops to −1.75 °C (28.85 °F) and then rises up to 12 °C (54 °F) in summer. This

1530-420: The bay. Skerry A skerry ( / ˈ s k ɛr i / SKEHRR -ee ) is a small rocky island , or islet , usually too small for human habitation. It may simply be a rocky reef . A skerry can also be called a low sea stack . A skerry may have vegetative life such as moss and small, hardy grasses. They are often used as resting places by animals such as seals and birds . The term skerry

1581-592: The bay. Later accounts report fighting and massacres on both sides. However, the primary reason for the abandonment of the Greenlandic settlements was the advent of the Little Ice Age that started in the 15th century. There was such an extreme shift in temperature that Disko Bay became inaccessible even in the warmer summer months, thereby destroying the livelihood of the Greenlandic Norse. Even

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1632-472: The black-backed gull) was heavily impacted by human fishing discards and fishing ports. Looking further at environmental drivers that structure bird habitat and distribution are human and climate impacts. Looking at waterbird distribution in wetlands, changes in salinity, water depth, water body isolation and hydroperiod altered bird community structure in both a species and guild specific way. Gulls in particular had high associations with salinity levels, being

1683-586: The chicks until they fledge . Although the chicks are fed by both parents, early on in the rearing period the male does most of the feeding and the female most of the brooding and guarding. The family Laridae was introduced (as Laridia) by the French polymath Constantine Samuel Rafinesque in 1815. The taxonomy of gulls is confused by their widespread distribution zones of hybridisation leading to gene flow . Some have traditionally been considered ring species , but research has suggested that this assumption

1734-411: The coasts near their breeding sites. A big influence on non-breeding gull distribution are food patches. Human fisheries especially have an impact since they often provide an abundant and predictable food resource. Looking at two species of gulls dependent on human fisheries, Audouin's gull ( Ichthyaetus audouinii ) and lesser black-backed gulls ( Larus fuscus) , their breeding distributions (especially

1785-510: The entire 1,600 km (1,000 mi) route from Stavanger to North Cape , Norway. The Blindleia is a skerry-protected waterway that starts near Kristiansand in southern Norway and continues past Lillesand . The Inside Passage provides a similar route from Seattle , Washington , to Skagway , Alaska , United States. Another such skerry-protected passage extends from the Straits of Magellan north for 800 km (500 mi) along

1836-400: The exceptions being Sabine's gull and swallow-tailed gulls , which have forked tails, and Ross's gull , which has a wedge-shaped tail. Gulls have moderately long legs, especially when compared to the similar terns, with fully webbed feet. The bill is generally heavy and slightly hooked, with the larger species having stouter bills than the smaller species. The bill colour is often yellow with

1887-422: The head varies by breeding season; in nonbreeding dark-hooded gulls, the hood is lost, sometimes leaving a single spot behind the eye, and in white-headed gulls, nonbreeding heads may have streaking. The gulls have a worldwide cosmopolitan distribution . They breed on every continent, including the margins of Antarctica , and are found in the high Arctic as well. They are less common on tropical islands, although

1938-703: The main environmental predictor for waterbird assemblage. Charadriiform birds drink salt water, as well as fresh water, as they possess exocrine glands located in supraorbital grooves of the skull by which salt can be excreted through the nostrils to assist the kidneys in maintaining electrolyte balance. Gulls are highly adaptable feeders that opportunistically take a wide range of prey. The food taken by gulls includes fish and marine and freshwater invertebrates, both alive and already dead; terrestrial arthropods and invertebrates such as insects and earthworms; rodents, eggs, carrion, offal , reptiles, amphibians, seeds, fruit, human refuse, and even other birds. No gull species

1989-502: The main source of income for the Greenlandic settlers who traded with Iceland, the British Isles, and mainland Europe. Without these resources the settlements would probably not have lasted as long as they did. Norse accounts describe the area as uninhabited when they first explored it. Norse accounts document an eventual trade arrangement with the Inuit who came from the north and west. For a time, both parties made peaceful use of

2040-463: The nest dry, particularly species that nest in tidal marshes . Both sexes gather nesting material and build the nest, but the division of labour is not always exactly equal. In coastal towns, many gulls nest on rooftops and can be observed by nearby human residents. Clutch size is typically three eggs, although some of the smaller gulls only lay two, and the swallow-tailed gull produces a single egg. Birds synchronise their laying within colonies, with

2091-677: The nesting site from others of their species. This area can be as large as a 5-metre radius around the nest in the herring gull to just a tiny area of cliff ledge in the kittiwakes . Most gulls breed once a year and have predictable breeding seasons lasting for three to five months. Gulls begin to assemble around the colony for a few weeks prior to occupying it. Existing pairs re-establish their pair-bonds , and unpaired birds begin courting. Pairs then move back into their territories, and new males establish new territories and attempt to court females. Gulls defend their territories from rivals of both sexes using calls and aerial attacks. Nest building

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2142-577: The northwest coast of Spain revealed a shift from a sardine to crustacean-based diet. This shift was linked to higher fishing efficiency and thus overall fish stock depletion. Lastly, closure of nearby open-air landfills limited food availability for the gulls, furthering creating a stress on their shift in diet. Between the years of 1974–1994, yellow-legged gull populations in Berlenga Island, Portugal, increased from 2600 to 44,698 individuals. Analyzing both adult and chick remains, researchers found

2193-471: The outlet of fjords where submerged glacially formed valleys at right angles to the coast join with other cross valleys in a complex array. In some places near the seaward margins of fjorded areas, the ice-scoured channels are so numerous and varied in direction that the rocky coast is divided into thousands of island blocks, some large and mountainous, while others are merely rocky points or rock reefs that menace navigation. The island fringe of Norway

2244-616: The resurrection of several genera. An older name for gulls is mews ; this still exists in certain regional English dialects and is cognate with German Möwe , Danish måge , Swedish mås , Dutch meeuw , Norwegian måke/måse , and French mouette . Typically medium to large in size, gulls are usually grey or white, often with black markings on the head or wings. They normally have harsh wailing or squawking calls; stout, longish bills; and webbed feet. Most gulls are ground-nesting piscivores or carnivores which take live food or scavenge opportunistically, particularly

2295-742: The rising islands as they break sea level, revealing till deposits and eventually clay bottoms. The skerries exist as small rocky islands before uplift of adjacent terrain changes the classification of this landform into a tombolo . In the Russian Federation , the best examples are the Minina Skerries , located in the Kara Sea , in the western shores of the Taymyr Peninsula , and the Sumsky Skerries , located in

2346-399: The smaller gulls tend to be more manoeuvrable while walking. The walking gait of gulls includes a slight side to side motion, something that can be exaggerated in breeding displays. In the air, they are able to hover and they are also able to take off quickly with little space. The general pattern of plumage in adult gulls is a white body with a darker mantle; the extent to which the mantle

2397-462: The surface when hunting. Examples of such associations include four species of gulls feeding around plumes of mud brought to the surface by feeding grey whales , and also between orcas (largest dolphin species) and kelp gulls (and other seabirds). Looking at the effect of humans on gull diet, overfishing of target prey such as sardines have caused a shift in diet and behaviour. Analysis of yellow-legged gull's ( Larus michahellis ) pellets off

2448-448: The water, and gulls may swim in tight circles or foot paddle to bring marine invertebrates up to the surface. Food is also obtained by searching the ground, often on the shore among sand, mud or rocks. Larger gulls tend to do more feeding in this way. In shallow water gulls may also engage in foot paddling. One method of obtaining prey involves dropping heavy shells of clams and mussels onto hard surfaces. Gulls may fly some distance to find

2499-555: The west coast of the South American continent. The Swedish coast along Bohuslän is likewise guarded by skerries. Even the east coast of Sweden, in the Baltic Sea , has many big skärgårdar (archipelagos), notably Stockholm Archipelago . The southwestern coast of Finland also has a great many skerries; so many, in fact, that they form an archipelago . This area is experiencing post-glacial rebound that connects

2550-444: The whale as it surfaces and pecking out pieces of flesh. Gulls range in size from the little gull , at 120 grams ( 4 + 1 ⁄ 4 ounces) and 29 centimetres ( 11 + 1 ⁄ 2 inches), to the great black-backed gull , at 1.75 kg (3 lb 14 oz) and 76 cm (30 in). They are generally uniform in shape, with heavy bodies, long wing, and moderately long necks. The tails of all but three species are rounded;

2601-460: The winter, but the extent to which they migrate varies by species. Some migrate long distances, notably Sabine's gull , which migrates from the Arctic coasts to winter off the west coasts of South America and southern Africa, and Franklin's gull , which migrates from Canada to wintering grounds off the west coast of South America. Other species move much shorter distances and may simply disperse along

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