Hudson Bay is a large with an area of 1.23 million km². It is a relatively shallow body of water in northeastern Canada. It drains a very large area that includes parts of Ontario, Quebec, Saskatchewan, Alberta, most of Manitoba, parts of North Dakota and Minnesota, and the southeastern area of Nunavut. A smaller offshoot of the bay, James Bay, lies to the south.
Hudson Bay is part of the Arctic Ocean. On the east it is connected with the Atlantic Ocean by Hudson Strait, and on the north with the rest of the Arctic Ocean by Foxe Basin (which is not considered part of the bay) and Fury and Hecla Strait.
The Eastern Cree name for the Hudson and James bays is Wînipekw (Southern dialect) or Wînipâkw (Northern dialect), meaning muddy or brackish water.
Hudson Bay has a salinity that is lower than the world ocean on average. This is caused mainly by three reasons:
1) the low rate of evaporation (the bay is ice-covered for much of the year)
2) the large volume of terrestrial runoff entering the bay (about 700 km³ annually) the Hudson Bay watershed covers much of Canada, with many rivers and streams discharging into the bay) and the annual melt of sea ice provides a significant source of fresher water to the surface layer (about three times as much as the rivers)
3) its limited connection with the larger Atlantic Ocean (and its higher salinity)
The western shores of the bay are a lowland known as the "Hudson Bay Lowlands" which cover 324,000 km². The area is drained by a large number of rivers and has formed a characteristic vegetation known as muskeg (a soil type (also a peatland or wetland type called a bog) common in arctic and boreal areas). Much of the landform has been shaped by the actions of glaciers and the shrinkage of the bay over long periods of time. Signs of numerous former beachfronts can be seen far inland from the current shore. A large portion of the lowlands is part of the Polar Bear Provincial Park.
In contrast, most of the eastern shores (the Quebec portion) form the western edge of the Canadian Shield in Quebec. The area is rocky and hilly. Its vegetation is typically boreal forest and to the north, tundra (an area where the tree growth is hindered by low temperatures and short growing seasons).
There are many islands in Hudson Bay, mostly near the eastern coast. All are part of the territory Nunavut. The main group of islands is known as the Belcher Islands.
Hudson Bay was named after Henry Hudson, who explored the bay in 1610 on his ship the Discovery. On this fourth voyage he worked his way around the west coast of Greenland and into the bay, mapping much of its eastern coast. The Discovery became trapped in the ice over the winter, and the crew survived onshore at the southern tip of James Bay. When the ice cleared in the spring Hudson wanted to explore the rest of the area, but the crew mutinied on June 22, 1611.
