Osprey in the context of "Aquatic bird"

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.

A food chain is a linear network of links in a food web, often beginning with an autotroph (such as grass or algae), also called a producer, and typically ending at an apex predator (such as grizzly bears or killer whales), detritivore (such as earthworms and woodlice), or decomposer (such as fungi or bacteria). A food web is distinct from a food chain. A food chain illustrates the associations between organisms according to the energy sources they consume in trophic levels, and the most common way to quantify them is in length: the number of links between a trophic consumer and the base of the chain.

Studies of food chains are essential to many biological studies.

The Mallows Bay–Potomac River National Marine Sanctuary is a National Marine Sanctuary in the United States located in the Potomac River in Charles County, Maryland. It is best known for the "Ghost Fleet," 118 historic shipwrecks in Mallows Bay in the sanctuary's northeast corner which is the largest shipwreck fleet in the Western Hemisphere. They are among more than 200 shipwrecks in the sanctuary, some of which date as far back as the American Revolutionary War and others to the American Civil War.

In addition to shipwrecks, the sanctuary preserves historical sites related to Native Americans, some of them as much as 12,000 years old, as well as a lengthy span of United States history, including the American Revolutionary War, the American Civil War, steamboat and steamship activity during the Industrial Revolution, and what was once an important Potomac River fishing industry. It also protects sites dating as far back as the 17th century related to African-American history, as well as an ecologically and biologically important area of the Potomac River and its Maryland shoreline that supports many species of plants and animals.

Abernethy Forest is a remnant of the Caledonian Forest in Strathspey, in the Highland council area of Scotland. It lies within the Cairngorms National Park, close to the villages of Nethy Bridge, Boat of Garten, and Aviemore. The forest is an RSPB reserve, close to Loch Garten Osprey Centre, which is also owned by the RSPB. It is popular with walkers, as there are various trails throughout the reserve. The forest forms part of the wider Abernethy National Nature Reserve.

There is approximately 4,000 hectares of forest within the reserve, and just under half of this is native Caledonian pine forest. Abernethy Forest is one of the largest remaining remnant of Caledonian pine forest in Scotland. The forest is home to a variety of birds and mammals, including Scottish crossbill, red squirrel, wildcat, red deer, black grouse, crested tit and osprey. There is also a capercaillie lek.

The Accipitridae (/ˌæksɪˈpɪtrɪdiː, -deɪ/) is one of the four families within the order Accipitriformes, and is a family of small to large birds of prey with strongly hooked bills and variable morphology based on diet. They feed on a range of prey items from insects to medium-sized mammals, with a number feeding on carrion and a few feeding on fruit. The Accipitridae have a cosmopolitan distribution, being found on all the world's continents (except Antarctica) and a number of oceanic island groups. Some species are migratory. The family contains 256 species which are divided into 12 subfamilies and 75 genera.

Many well-known birds such as hawks, eagles, kites, harriers and Old World vultures are included in this group. The osprey is usually placed in a separate family (Pandionidae), as is the secretary bird (Sagittariidae), and the New World vultures are also usually now regarded as a separate family or order. Karyotype data indicate the accipitrids analysed are indeed a distinct monophyletic group.

The Innoko National Wildlife Refuge is a national wildlife refuge of the United States located in western Alaska. It consists of 3,850,481 acres (15,582 km), of which 1,240,000 acres (5,018 km) is designated a wilderness area. It is the fifth-largest national wildlife refuge in the United States. The refuge is administered from offices in Galena.

The refuge was established in 1980 by the Alaska National Interest Lands Conservation Act. The northern part of the refuge, called Kaiyuh Flats, is adjacent to the Yukon River southwest of Galena. It contains 751,000 acres (3,040 km). The southern part contains approximately 3,099,000 acres (12,540 km) of land surrounding the Innoko River. The land is swampy and is the nesting area for hundreds of thousands of birds including ospreys, northern hawk-owls, trumpeter swans, bald eagles, common ravens, short-eared owls, and red-tailed hawks. Mammalian species that habitat this refuge are brown and black bears, moose, wolves, Canadian lynx, marten, porcupine, beaver, caribou, river otter, red fox, wolverine, muskrat, and mink.