Wader in the context of "East-Atlantic flyway"

A water bird, alternatively waterbird or aquatic bird, is a bird that lives on or around water. In some definitions, the term water bird is especially applied to birds in freshwater ecosystems, although others make no distinction from seabirds that inhabit marine environments. Some water birds (e.g. wading birds) are more terrestrial while others (e.g. waterfowls) are more aquatic, and their adaptations will vary depending on their environment. These adaptations include webbed feet, beaks, and legs adapted to feed in the water, and the ability to dive from the surface or the air to catch prey in water.

The term aquatic bird is sometimes also used in this context. A related term that has a narrower meaning is waterfowl. Some piscivorous birds of prey, such as ospreys, sea eagles, fish eagles, fish owls, and fishing owls, hunt aquatic prey but do not stay in water for long and live predominantly over dry land, and are not considered water birds. The term waterbird is also used in the context of conservation to refer to any birds that inhabit or depend on bodies of water or wetland areas. Examples of this use include the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) and the Wallnau Waterbird Reserve.

Port Phillip (Kulin: Narm-Narm) or Port Phillip Bay is a horsehead-shaped enclosed bay on the central coast of southern Victoria, Australia. The bay opens into the Bass Strait via a short, narrow channel known as The Rip, and is completely surrounded by localities of Victoria's two largest cities — metropolitan Greater Melbourne in the bay's main eastern portion north of the Mornington Peninsula, and the city of Greater Geelong in the much smaller western portion (known as the Corio Bay) north of the Bellarine Peninsula. Geographically, the bay covers 1,930 km (750 sq mi) and the shore stretches roughly 264 km (164 mi), with the volume of water around 25 km (6.0 cu mi). Most of the bay is navigable, although it is extremely shallow for its size — the deepest portion is only 24 m (79 ft) and half the bay is shallower than 8 m (26 ft). Its waters and coast are home to seals, whales, dolphins, corals and many kinds of seabirds and migratory waders.

Before European settlement, the area around Port Phillip was divided between the territories of the Wathaurong (west), Wurundjeri (north) and Boonwurrung (south and east) people, all part of the indigeous Kulin nation. The first Europeans to enter the bay were the crews of HMS Lady Nelson, commanded by John Murray and, ten weeks later, HMS Investigator commanded by Matthew Flinders, in 1802. Subsequent expeditions into the bay took place in 1803 to establish the first settlement in Victoria, near Sorrento, but was abandoned in 1804. Thirty years later, settlers from Tasmania returned to establish Melbourne (now Victoria's capital city) at the mouth of the Yarra River in 1835, and Geelong at Corio Bay in 1838. Today, Port Phillip is the most densely populated catchment in Australia with an estimated 5.5 million people living around the bay; Melbourne's suburbs extend around much of the northern and eastern shorelines, and the city of Geelong sprawls around Corio Bay in the bay's western arm.

The webbed foot is a specialized limb with interdigital membranes (webbings) that aids in aquatic locomotion, present in a variety of tetrapod vertebrates. This adaptation is primarily found in semiaquatic species, and has convergently evolved many times across vertebrate taxa.

It likely arose from mutations in developmental genes that normally cause tissue between the digits to apoptose. These mutations were beneficial to many semiaquatic animals because the increased surface area from the webbing allowed for more swimming propulsion and swimming efficiency, especially in surface swimmers. The webbed foot also has enabled other novel behaviors like escape responses and mating behaviors. A webbed foot may also be called a paddle to contrast it from a more hydrofoil-like flipper.

The ruff (Calidris pugnax) is a medium-sized wading bird that breeds in marshes and wet meadows across northern Eurasia. This highly gregarious sandpiper is migratory and sometimes forms huge flocks in its winter grounds, which include southern and western Europe, Africa, southern Asia and Australia.

The ruff is a long-necked, pot-bellied bird. This species shows marked sexual dimorphism; the male is much larger than the female (the reeve), and has a breeding plumage that includes brightly coloured head tufts, bare orange facial skin, extensive black on the breast, and the large collar of ornamental feathers that inspired this bird's English name. The female and the non-breeding male have grey-brown upperparts and mainly white underparts. Three differently plumaged types of male, including a rare form that mimics the female, use a variety of strategies to obtain mating opportunities at a lek, and the colourful head and neck feathers are erected as part of the elaborate main courting display. The female has one brood per year and lays four eggs in a well-hidden ground nest, incubating the eggs and rearing the chicks, which are mobile soon after hatching, on her own. Predators of wader chicks and eggs include mammals such as foxes, feral cats and stoats, and birds such as large gulls, crows and skuas.

Gulls and seagulls are seabirds of the subfamily Larinae. 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 the resurrection and revision 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.

Gulls are usually grey or white, often with black markings on the head or wings. They normally have harsh wailing or squawking calls, stout bills, and webbed feet. Most gulls are ground-nesting piscivores or carnivores which take live food or scavenge opportunistically, particularly 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 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 a maximum age of 49 years recorded for the European herring gull.

Foxe Basin is a shallow oceanic basin north of Hudson Bay, in Nunavut, Canada, located between Baffin Island and the Melville Peninsula. For most of the year, it is blocked by sea ice (fast ice) and drift ice made up of multiple ice floes.

The nutrient-rich cold waters found in the basin are especially favourable to phytoplankton and the numerous islands within it are important bird habitats, including Sabine's gulls and many types of shorebirds. Bowhead whales migrate to the northern part of the basin each summer.