Hudson Bay, sometimes called Hudson's Bay (usually historically), is a large body of saltwater in northeastern Canada with a surface area of . It is located north of

Ontario Ontario is the southernmost Provinces and territories of Canada, province of Canada. Located in Central Canada, Ontario is the Population of Canada by province and territory, country's most populous province. As of the 2021 Canadian census, it ...

, west of

Quebec Quebec is Canada's List of Canadian provinces and territories by area, largest province by area. Located in Central Canada, the province shares borders with the provinces of Ontario to the west, Newfoundland and Labrador to the northeast, ...

, northeast of

Manitoba Manitoba is a Provinces and territories of Canada, province of Canada at the Centre of Canada, longitudinal centre of the country. It is Canada's Population of Canada by province and territory, fifth-most populous province, with a population ...

, and southeast of

Nunavut Nunavut is the largest and northernmost Provinces and territories of Canada#Territories, territory of Canada. It was separated officially from the Northwest Territories on April 1, 1999, via the ''Nunavut Act'' and the Nunavut Land Claims Agr ...

, but politically entirely part of Nunavut. It is an inland

marginal sea This is a list of seas of the World Ocean, including marginal seas, areas of water, various gulfs, bights, bays, and straits. In many cases it is a matter of tradition for a body of water to be named a sea or a bay, etc., therefore all these ...

of the

Arctic Ocean The Arctic Ocean is the smallest and shallowest of the world's five oceanic divisions. It spans an area of approximately and is the coldest of the world's oceans. The International Hydrographic Organization (IHO) recognizes it as an ocean, ...

. The

Hudson Strait Hudson Strait () in Nunavut links the Atlantic Ocean and the Labrador Sea to Hudson Bay in Canada. This strait lies between Baffin Island and Nunavik, with its eastern entrance marked by Cape Chidley in Newfoundland and Labrador and Nunavut ...

provides a connection between the

Labrador Sea The Labrador Sea (; ) is an arm of the North Atlantic Ocean between the Labrador Peninsula and Greenland. The sea is flanked by continental shelf, continental shelves to the southwest, northwest, and northeast. It connects to the north with Baffi ...

and the Atlantic Ocean in the northeast, while the Foxe Channel connects Hudson Bay with the Arctic Ocean in the north. The

Hudson Bay drainage basin The Hudson Bay drainage basin is the drainage basin in northern North America where surface water empties into the Hudson Bay and adjoining waters. Spanning an area of about and with a mean discharge of about , the basin is almost entirely wi ...

drains a very large area, about , that includes parts of southeastern Nunavut,

Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...

Saskatchewan Saskatchewan is a Provinces and territories of Canada, province in Western Canada. It is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and to the south by the ...

, all of

, and parts of the U.S. states of

North Dakota North Dakota ( ) is a U.S. state in the Upper Midwest, named after the indigenous Dakota people, Dakota and Sioux peoples. It is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north and by the U.S. states of Minneso ...

South Dakota South Dakota (; Sioux language, Sioux: , ) is a U.S. state, state in the West North Central states, North Central region of the United States. It is also part of the Great Plains. South Dakota is named after the Dakota people, Dakota Sioux ...

Minnesota Minnesota ( ) is a U.S. state, state in the Upper Midwestern region of the United States. It is bordered by the Canadian provinces of Manitoba and Ontario to the north and east and by the U.S. states of Wisconsin to the east, Iowa to the so ...

, and

Montana Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, an ...

. Hudson Bay's southern arm is called

James Bay James Bay (, ; ) is a large body of water located on the southern end of Hudson Bay in Canada. It borders the provinces of Quebec and Ontario, and is politically part of Nunavut. Its largest island is Akimiski Island. Numerous waterways of the ...

. The Eastern Cree name for Hudson and James Bay is (southern dialect) or (northern dialect), meaning muddy or brackish water.

Lake Winnipeg Lake Winnipeg () is a very large, relatively shallow lake in North America, in the Canadian province of Manitoba. Its southern end is about north of the city of Winnipeg. Lake Winnipeg is Canada's sixth-largest freshwater lake and the third- ...

is similarly named by the local

Cree The Cree, or nehinaw (, ), are a Indigenous peoples of the Americas, North American Indigenous people, numbering more than 350,000 in Canada, where they form one of the country's largest First Nations in Canada, First Nations. They live prim ...

, as is the location for the city of

Winnipeg Winnipeg () is the capital and largest city of the Provinces and territories of Canada, Canadian province of Manitoba. It is centred on the confluence of the Red River of the North, Red and Assiniboine River, Assiniboine rivers. , Winnipeg h ...

Description

The bay is named after

Henry Hudson Henry Hudson ( 1565 – disappeared 23 June 1611) was an English sea explorer and navigator during the early 17th century, best known for his explorations of present-day Canada and parts of the Northeastern United States. In 1607 and 16 ...

, an Englishman sailing for the

Dutch East India Company The United East India Company ( ; VOC ), commonly known as the Dutch East India Company, was a chartered company, chartered trading company and one of the first joint-stock companies in the world. Established on 20 March 1602 by the States Ge ...

, and after whom the river that he explored in 1609 is also named. Hudson Bay encompasses , making it the second-largest water body using the term "

bay A bay is a recessed, coastal body of water that directly connects to a larger main body of water, such as an ocean, a lake, or another bay. A large bay is usually called a ''gulf'', ''sea'', ''sound'', or ''bight''. A ''cove'' is a small, ci ...

" in the world (after the

Bay of Bengal The Bay of Bengal is the northeastern part of the Indian Ocean. Geographically it is positioned between the Indian subcontinent and the Mainland Southeast Asia, Indochinese peninsula, located below the Bengal region. Many South Asian and Southe ...

). The bay is relatively shallow and is considered an epicontinental sea, with an average depth of about (compared to in the

). It is about long and wide.Private Tutor
. Infoplease.com. Retrieved on 12 April 2014. On the east it is connected with the Arctic Ocean (

Davis Strait The Davis Strait (Danish language, Danish: ''Davisstrædet'') is a southern arm of the Arctic Ocean that lies north of the Labrador Sea. It lies between mid-western Greenland and Baffin Island in Nunavut, Canada. To the north is Baffin Bay. The ...

) by

; on the north, with the

by Foxe Basin (which is not considered part of the bay), and

Fury and Hecla Strait Fury and Hecla Strait is a narrow (from wide) Arctic seawater channel located in the Qikiqtaaluk Region of Nunavut, Canada. Geography Situated between Baffin Island to the north and the Melville Peninsula to the south, it connects Foxe Basin o ...

. Hudson Bay is often considered part of the Arctic Ocean: the

International Hydrographic Organization The International Hydrographic Organization (IHO) (French: ''Organisation Hydrographique Internationale'') is an intergovernmental organization representing hydrography. the IHO comprised 102 member states. A principal aim of the IHO is to ...

, in its 2002 working draft of ''Limits of Oceans and Seas'', defined Hudson Bay, with its outlet extending from 62.5 to 66.5 degrees north (just a few miles south of the

Arctic Circle The Arctic Circle is one of the two polar circles, and the northernmost of the five major circle of latitude, circles of latitude as shown on maps of Earth at about 66° 34' N. Its southern counterpart is the Antarctic Circle. The Arctic Circl ...

) as being part of the Arctic Ocean, specifically "Arctic Ocean Subdivision 9.11". Other authorities include it in the Atlantic, in part because of its greater water budget connection with that ocean.

History

The search for a western route to

Cathay Cathay ( ) is a historical name for China that was used in Europe. During the early modern period, the term ''Cathay'' initially evolved as a term referring to what is now Northern China, completely separate and distinct from ''China'', which w ...

and the

East Indies The East Indies (or simply the Indies) is a term used in historical narratives of the Age of Discovery. The ''Indies'' broadly referred to various lands in Eastern world, the East or the Eastern Hemisphere, particularly the islands and mainl ...

, which had been actively pursued since the days of

Christopher Columbus Christopher Columbus (; between 25 August and 31 October 1451 – 20 May 1506) was an Italians, Italian explorer and navigator from the Republic of Genoa who completed Voyages of Christopher Columbus, four Spanish-based voyages across the At ...

and

John Cabot John Cabot ( ; 1450 – 1499) was an Italians, Italian navigator and exploration, explorer. His 1497 voyage to the coast of North America under the commission of Henry VII of England, Henry VII, King of England is the earliest known Europe ...

, in the latter part of the 15th century, directly resulted in the first sighting of Hudson Bay by Europeans. English explorers and colonists named Hudson Bay after Sir

who explored the bay beginning 2 August 1610, on his ship ''

Discovery Discovery may refer to: * Discovery (observation), observing or finding something unknown * Discovery (fiction), a character's learning something unknown * Discovery (law), a process in courts of law relating to evidence Discovery, The Discovery ...

''. On his fourth voyage to North America, Hudson worked his way around

Greenland Greenland is an autonomous territory in the Danish Realm, Kingdom of Denmark. It is by far the largest geographically of three constituent parts of the kingdom; the other two are metropolitan Denmark and the Faroe Islands. Citizens of Greenlan ...

's west coast and into the bay, mapping much of its eastern coast. ''Discovery'' became trapped in the ice over the winter, and the crew survived onshore at the southern tip of

. In the spring, as the ice receded, Henry Hudson expressed a desire to continue exploring the uncharted region. However, on 22 June 1611, the crew mutinied. They left Hudson and others adrift in a small boat. The fate of Hudson and the other men stranded with him remains undetermined. Nevertheless, there is little evidence in historical documents to suggest that they persisted for a long time thereafter. In May 1612, Sir Thomas Button sailed from England with two ships to look for Henry Hudson, and to continue the search for the

Northwest Passage The Northwest Passage (NWP) is the sea lane between the Atlantic and Pacific oceans through the Arctic Ocean, near the northern coast of North America via waterways through the Arctic Archipelago of Canada. The eastern route along the Arctic ...

to Asia. In 1668, '' Nonsuch'' reached the bay and traded for

beaver Beavers (genus ''Castor'') are large, semiaquatic rodents of the Northern Hemisphere. There are two existing species: the North American beaver (''Castor canadensis'') and the Eurasian beaver (''C. fiber''). Beavers are the second-large ...

pelts, leading to the creation of the

Hudson's Bay Company The Hudson's Bay Company (HBC), originally the Governor and Company of Adventurers of England Trading Into Hudson’s Bay, is a Canadian holding company of department stores, and the oldest corporation in North America. It was the owner of the ...

(HBC), which still bears the historic name. The HBC negotiated a trading monopoly from the

English Crown This list of kings and reigning queens of the Kingdom of England begins with Alfred the Great, who initially ruled Wessex, one of the seven Anglo-Saxon kingdoms which later made up modern England. Alfred styled himself king of the Anglo-Sax ...

for the Hudson Bay watershed, called

Rupert's Land Rupert's Land (), or Prince Rupert's Land (), was a territory in British North America which comprised the Hudson Bay drainage basin. The right to "sole trade and commerce" over Rupert's Land was granted to Hudson's Bay Company (HBC), based a ...

. In 1670, the English Crown granted a charter to facilitate fur trading within the

. France contested this grant by sending several military expeditions to the region, but abandoned its claim in the

Treaty of Utrecht The Peace of Utrecht was a series of peace treaty, peace treaties signed by the belligerents in the War of the Spanish Succession, in the Dutch city of Utrecht between April 1713 and February 1715. The war involved three contenders for the vac ...

(April 1713). The Treaty of Utrecht, signed on 11 April 1713, marked a significant agreement between Britain and France. The treaty was negotiated in Utrecht, Netherlands, and marked a crucial stage in the conclusion of the

War of the Spanish Succession The War of the Spanish Succession was a European great power conflict fought between 1701 and 1714. The immediate cause was the death of the childless Charles II of Spain in November 1700, which led to a struggle for control of the Spanish E ...

. Its provisions had a significant impact in shaping the postwar landscape and establishing a new order in both Europe and North America. French concessions in North America as outlined in the Treaty of Utrecht included: Hudson Bay region,

Nova Scotia Nova Scotia is a Provinces and territories of Canada, province of Canada, located on its east coast. It is one of the three Maritime Canada, Maritime provinces and Population of Canada by province and territory, most populous province in Atlan ...

, and

Newfoundland Newfoundland and Labrador is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region of Labrador, having a total size of . As of 2025 the population ...

. During this period, the HBC built several

factories A factory, manufacturing plant or production plant is an industrial facility, often a complex consisting of several buildings filled with machinery, where workers manufacture items or operate machines which process each item into another. Th ...

(

forts A fortification (also called a fort, fortress, fastness, or stronghold) is a military construction designed for the defense of territories in warfare, and is used to establish rule in a region during peacetime. The term is derived from ...

and

trading post A trading post, trading station, or trading house, also known as a factory in European and colonial contexts, is an establishment or settlement where goods and services could be traded. Typically a trading post allows people from one geogr ...

s) along the coast at the mouth of the major rivers (such as

Fort Severn Fort Severn, in present-day Annapolis, Maryland, was built in 1808 on the same site as an earlier American Revolutionary War fort of 1776. Although intended to guard Annapolis harbor from British attack during the War of 1812, it never saw act ...

;

York Factory York Factory was a settlement and Hudson's Bay Company (HBC) factory (trading post) on the southwestern shore of Hudson Bay in northeastern Manitoba, Canada, at the mouth of the Hayes River, approximately south-southeast of Churchill. York ...

, Churchill; and the Prince of Wales Fort). The strategic locations were bases for inland exploration. More importantly, they were trading posts with

Indigenous peoples There is no generally accepted definition of Indigenous peoples, although in the 21st century the focus has been on self-identification, cultural difference from other groups in a state, a special relationship with their traditional territ ...

who came to them with furs from their trapping season. The HBC shipped the furs to Europe and continued to use some of these posts well into the 20th century. The HBC's trade monopoly was abolished in 1870, by a British

Order in Council An Order in Council is a type of legislation in many countries, especially the Commonwealth realms. In the United Kingdom, this legislation is formally made in the name of the monarch by and with the advice and consent of the Privy Council ('' ...

called the

Deed of Surrender The Deed of Surrender or Rupert's Land and North-Western Territory Order is an 1870 British order in council that transferred ownership of Rupert's Land and the North-Western Territory from the United Kingdom to the newly created Dominion of C ...

, ceded Rupert's Land to Canada, an area of approximately , as part of the

Northwest Territories The Northwest Territories is a federal Provinces and territories of Canada, territory of Canada. At a land area of approximately and a 2021 census population of 41,070, it is the second-largest and the most populous of Provinces and territorie ...

. In 1912, the western shore south of 60° and, following the Quebec Boundaries Extension Act, 1912, all the eastern shore were transferred to the adjacent provinces, but the bay and offshore islands remained part of the Northwest Territories. Starting in 1913, the bay was extensively charted by the Canadian government's to develop it for navigation. This mapping progress led to the establishment of Churchill, Manitoba, as a deep-sea port for wheat exports in 1929, after unsuccessful attempts at Port Nelson. The Port of Churchill was an important shipping link for trade with Europe and Russia until its closure in 2016 by owner

OmniTRAX OmniTRAX, Inc. is a transportation and transportation infrastructure holding company based in Denver, Colorado, in the United States. It primarily owns or operates railroads, with a network of 25 regional and shortline railroads in 12 U.S. state ...

. The port and the Hudson Bay Railway were then sold to the Arctic Gateway Group—a consortium of

First Nations First nations are indigenous settlers or bands. First Nations, first nations, or first peoples may also refer to: Indigenous groups *List of Indigenous peoples *First Nations in Canada, Indigenous peoples of Canada who are neither Inuit nor Mé ...

, local governments, and corporate investors—in 2018. On 9 July 2019, ships resupplying Arctic communities began stopping at the port for additional cargo, and the port began shipping grain again on 7 September 2019.

Geography and climate

Extent

The

defines the northern limit of Hudson Bay as follows:

Climate

Northern Hudson Bay has a

polar climate The polar climate regions are characterized by a lack of warm summers but with varying winters. Every month a polar climate has an average temperature of less than . Regions with a polar climate cover more than 20% of the Earth's area. Most of ...

(

Köppen Köppen is a German surname. Notable people with the surname include: * Bernd Köppen (1951–2014), German pianist and composer * Carl Köppen (1833-1907), German military advisor in Meiji era Japan * Edlef Köppen (1893–1939), German author ...

: ''ET'') being one of the few places in the world where this type of climate is found south of 60 °N, going farther south towards

, where Inukjuak is still dominated by the

tundra In physical geography, a tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. There are three regions and associated types of tundra: #Arctic, Arctic, Alpine tundra, Alpine, and #Antarctic ...

. From

Arviat Arviat (, Inuktitut syllabics, syllabics: ᐊᕐᕕᐊᑦ; formerly called Eskimo Point until 1 June 1989) is a predominantly Inuit Hamlet (place)#Canada, hamlet located on the western shore of Hudson Bay in the Kivalliq Region of Nunavut, Canada ...

, to the west to the south and southeast prevails the

subarctic climate The subarctic climate (also called subpolar climate, or boreal climate) is a continental climate with long, cold (often very cold) winters, and short, warm to cool summers. It is found on large landmasses, often away from the moderating effects of ...

(Köppen: ''Dfc''). This is because in the central summer months, heat waves can advance from the hot land and make the weather milder, with the result that the average temperature surpasses . The bay receives water from various surrounding rivers and currents originating from the Foxe Basin in the north, resulting in a counterclockwise overall flow. At the extreme southern tip of the extension known as James Bay arises a

humid continental climate A humid continental climate is a climatic region defined by Russo-German climatologist Wladimir Köppen in 1900, typified by four distinct seasons and large seasonal temperature differences, with warm to hot (and often humid) summers, and cold ...

with a longer and generally hotter summer. (Köppen: ''Dfb''). The average annual temperature in almost the entire bay is around or below. In the extreme northeast, winter temperatures average as low as . The Hudson Bay region has very low year-round average temperatures. The average annual temperature for Churchill at 59°N is and Inukjuak, facing cool westerlies in summer at 58°N, an even colder . By comparison,

Magadan Magadan ( rus, Магадан, p=məɡɐˈdan) is a Port of Magadan, port types of inhabited localities in Russia, town and the administrative centre of Magadan Oblast, Russia. The city is located on the isthmus of the Staritsky Peninsula by the ...

, in a comparable position at 59°N on the Eurasian landmass in the

Russian Far East The Russian Far East ( rus, Дальний Восток России, p=ˈdalʲnʲɪj vɐˈstok rɐˈsʲiɪ) is a region in North Asia. It is the easternmost part of Russia and the Asia, Asian continent, and is coextensive with the Far Easte ...

and with a similar

, has an annual average of . Vis-à-vis geographically closer Europe, contrasts stand much more extreme.

Arkhangelsk Arkhangelsk (, ) is a types of inhabited localities in Russia, city and the administrative center of Arkhangelsk Oblast, Russia. It lies on both banks of the Northern Dvina near its mouth into the White Sea. The city spreads for over along the ...

at 64°N in northwestern Russia has an average of , while the mild continental coastline of

Stockholm Stockholm (; ) is the Capital city, capital and List of urban areas in Sweden by population, most populous city of Sweden, as well as the List of urban areas in the Nordic countries, largest urban area in the Nordic countries. Approximately ...

at 59°N on the shore of an analogous large hyposaline marine inlet – the

Baltic Sea The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by the countries of Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden, and the North European Plain, North and Central European Plain regions. It is the ...

– has an annual average of . Water temperature peaks at on the western side of the bay in late summer. It is largely frozen over from mid-December to mid-June, when it usually clears from its eastern end westwards and southwards. A steady increase in regional temperatures over the last 100 years has led to decreases in the extent of the sea ice in Hudson Bay by 19.5% per decade. As well as a lengthening of the ice-free period, which was as short as four months in the late 17th century. The polar climate of Hudson Bay means it is home for a variety of polar climate animals, in the Western Hudson Bay (WHB) beluga whale population is the most significant known group in the

Canadian Arctic Northern Canada (), colloquially the North or the Territories, is the vast northernmost region of Canada, variously defined by geography and politics. Politically, the term refers to the three territories of Canada: Yukon, Northwest Territories a ...

, estimated to consist of approximately 54,473 individuals.

Waters

Hudson Bay has a lower average

salinity Salinity () is the saltiness or amount of salt (chemistry), salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensio ...

level than that of ocean water. The main causes are the low rate of evaporation (the bay is ice-covered for much of the year), the large volume of terrestrial runoff entering the bay (about annually, the Hudson Bay watershed covering much of Canada, many rivers and streams discharging into the bay), and the limited connection with the Atlantic Ocean and its higher salinity.

Sea ice Sea ice arises as seawater freezes. Because ice is less density, dense than water, it floats on the ocean's surface (as does fresh water ice). Sea ice covers about 7% of the Earth's surface and about 12% of the world's oceans. Much of the world' ...

is about three times the annual river flow into the bay, and its annual freezing and thawing significantly alters the salinity of the surface layer. Although its exact effects are not fully understood currently, the cyclonic storms in the bay are responsible for synoptic variability of salinity along the coast. One consequence of the lower salinity of the bay is that the

freezing point The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state of matter, state from solid to liquid. At the melting point the solid and liquid phase (matter), phase exist in Thermodynamic equilib ...

of the water is higher than in the rest of the world's oceans, thus decreasing the time that the bay remains ice-free. The increase of river inflows during the winter has decreased the season of sea ice by more than one month since the 1960s. The lower salinity of the bay also has effects on the distribution and prevalence of common marine life such as micro algae. Research has shown that the lower salinity of the Hudson Bay limits the growth of micro algae, which causes a notable change in biomass along the bay's salinity gradient.

Shores

The western shores of the bay are a

lowland Upland and lowland are conditional descriptions of a plain based on elevation above sea level. In studies of the ecology of freshwater rivers, habitats are classified as upland or lowland. Definitions Upland and lowland are portions of a ...

known as the

Hudson Bay Lowlands The Hudson Bay Lowlands is a vast wetland located between the Canadian Shield and southern shores of Hudson Bay and James Bay. Most of the area lies within the province of Ontario, with smaller portions reaching into Manitoba and Quebec. Many wide ...

, covering , and are Canada's largest continuous

peatland A peatland is a type of wetland whose soils consist of Soil organic matter, organic matter from decaying plants, forming layers of peat. Peatlands arise because of incomplete decomposition of organic matter, usually litter from vegetation, du ...

. Much of the landform has been shaped by the actions of

glacier A glacier (; or ) is a persistent body of dense ice, a form of rock, that is constantly moving downhill under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires ...

s and the shrinkage of the bay over long periods of time. The coastal area, located in a region characterized by permanently frozen layers of soil, known as

permafrost Permafrost () is soil or underwater sediment which continuously remains below for two years or more; the oldest permafrost has been continuously frozen for around 700,000 years. Whilst the shallowest permafrost has a vertical extent of below ...

, is a low-lying wetland that receives water from lakes and fast-flowing rivers. Signs of numerous former beach fronts can be seen far inland from the current shore. A large portion of the lowlands in the province of Ontario is part of the Polar Bear Provincial Park, and a similar portion of the lowlands in Manitoba is contained in

Wapusk National Park Wapusk National Park () is Canada's 37th national park, established in 1996. The name comes from the Cree word for polar bear (''wâpask''). Located on the shores of Hudson Bay in the Hudson Plains ecozone south of Churchill, its accessibil ...

, the latter location being a significant

maternity den In the animal, animal kingdom, a maternity den is a lair where a mother gives birth and nurtures her young when they are in a vulnerable biological life cycle, life stage. While dens are typically subterranea (geography), subterranean, they may al ...

ning area for

polar bear The polar bear (''Ursus maritimus'') is a large bear native to the Arctic and nearby areas. It is closely related to the brown bear, and the two species can Hybrid (biology), interbreed. The polar bear is the largest extant species of bear ...

s. In contrast, most of the eastern shores (the Quebec portion) form the western edge of the

Canadian Shield The Canadian Shield ( ), also called the Laurentian Shield or the Laurentian Plateau, is a geologic shield, a large area of exposed Precambrian igneous and high-grade metamorphic rocks. It forms the North American Craton (or Laurentia), th ...

in Quebec. The area is rocky and hilly. Its vegetation is typically

boreal forest Taiga or tayga ( ; , ), also known as boreal forest or snow forest, is a biome characterized by pinophyta, coniferous forests consisting mostly of pines, spruces, and larches. The taiga, or boreal forest, is the world's largest land biome. I ...

.The northern shores are

. Measured by shoreline, Hudson Bay is the largest bay in the world (the largest in area being the Bay of Bengal). The distinctive arcuate segment on the eastern shore of Hudson Bay is referred to as the Nastapoka arc.

Islands

There are many islands in Hudson Bay, mostly near the eastern coast. All the islands, including those in James Bay, are part of Nunavut and lie in the

Arctic Archipelago The Arctic Archipelago, also known as the Canadian Arctic Archipelago, is an archipelago lying to the north of the Canadian continental mainland, excluding Greenland (an autonomous territory of the Danish Realm, which is, by itself, much larger ...

. Several are disputed by the Cree. One group of islands is the Belcher Islands. The Belcher Islands are located in the centre of the Nastapoka arc. Another group includes the Ottawa Islands which are located near the eastern shore of the Hudson Bay.

Geology

Hudson Bay occupies a large

structural basin A structural basin is a large-scale structural geology, structural formation of rock stratum, strata formed by tectonics, tectonic warping (Fold (geology), folding) of previously flat-lying strata into a syncline fold. They are geological dep ...

, known as the Hudson Bay basin, that lies within the

. The collection and interpretation of outcrop, seismic and drill hole data for exploration for oil and gas reservoirs within the Hudson Bay basin found that it is filled by, at most, of

Ordovician The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era, and the second of twelve periods of the Phanerozoic Eon (geology), Eon. The Ordovician spans 41.6 million years f ...

to Devonian

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

, dolomite,

evaporite An evaporite () is a water- soluble sedimentary mineral deposit that results from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporite deposits: marine, which can also be described as oce ...

s, black

shale Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of Clay mineral, clay minerals (hydrous aluminium phyllosilicates, e.g., Kaolinite, kaolin, aluminium, Al2Silicon, Si2Oxygen, O5(hydroxide, OH)4) and tiny f ...

s, and various

clastic Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus,Essentials of Geology, 3rd Ed, Stephen Marshak, p. G-3 chunks, and smaller grains of rock broken off other rocks by ...

sedimentary rock Sedimentary rocks are types of rock (geology), rock formed by the cementation (geology), cementation of sediments—i.e. particles made of minerals (geological detritus) or organic matter (biological detritus)—that have been accumulated or de ...

s that overlie less than of Cambrian

strata In geology and related fields, a stratum (: strata) is a layer of Rock (geology), rock or sediment characterized by certain Lithology, lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by v ...

that consist of unfossiliferous quartz sandstones and conglomerates, overlain by sandy and stromatolitic dolomites. In addition, a minor amount of terrestrial

fluvial A river is a natural stream of fresh water that flows on land or inside caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of its course if it ru ...

sands and gravels of the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...

period are preserved in the fill of a prominent ring-like depression about across created by the dissolution of

Silurian The Silurian ( ) is a geologic period and system spanning 23.5 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the third and shortest period of t ...

evaporites during the Cretaceous period.Burgess, P.M., 2008, ''Phanerozoic evolution of the sedimentary cover of the North American craton.'', in Miall, A.D., ed., ''Sedimentary Basins of the United States and Canada'', Elsevier Science, Amsterdam, pp. 31–63.Lavoie, D., Pinet, N., Dietrich, J. and Chen, Z., 2015. ''The Paleozoic Hudson Bay Basin in northern Canada: New insights into hydrocarbon potential of a frontier intracratonic basin.'' ''American Association of Petroleum Geologists Bulletin'', 99(5), pp. 859–888.Roksandic, M.M., 1987, ''The tectonics and evolution of the Hudson Bay region'', in C. Beaumont and A. J. Tankard, eds., ''Sedimentary basins and basin-forming mechanisms.'' Canadian Society of Petroleum Geologists Memoir 12, p. 507–518.Sanford, B.V. and Grant, A.C., 1998. ''Paleozoic and Mesozoic geology of the Hudson and southeast Arctic platforms.'' ''Geological Survey of Canada Open File 3595'', scale 1:2 500 000. From the large quantity of published geologic data that has been collected as the result of hydrocarbon exploration, academic research, and related

geological map A geological map or geologic map is a special-purpose map made to show various geological features. Rock (geology), Rock units or stratum, geologic strata are shown by color or symbols. Bed (geology), Bedding planes and structural features such ...

ping, a detailed history of the Hudson Bay basin has been reconstructed. During the majority of the

Cambrian The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordov ...

Period, this basin did not exist. Rather, this part of the Canadian Shield area was still topographically high and emergent. It was only during the later part of the Cambrian that the rising sea level of the Sauk

marine transgression A marine transgression is a geologic event where sea level rises relative to the land and the shoreline moves toward higher ground, resulting in flooding. Transgressions can be caused by the land sinking or by the ocean basins filling with water ...

slowly submerged it. During the Ordovician, this part of the Canadian Shield continued to be submerged by rising sea levels except for a brief middle Ordovician

marine regression A marine regression is a geological process occurring when areas of submerged seafloor are exposed during a drop in sea level. The opposite event, marine transgression, occurs when flooding from the sea covers previously-exposed land. Descript ...

. Only starting in the Late Ordovician and continuing into the Silurian did the gradual regional

subsidence Subsidence is a general term for downward vertical movement of the Earth's surface, which can be caused by both natural processes and human activities. Subsidence involves little or no horizontal movement, which distinguishes it from slope mov ...

of this part of the Canadian Shield form the Hudson Bay basin. The formation of this basin resulted in the accumulation of black

bituminous Bitumen ( , ) is an immensely viscous constituent of petroleum. Depending on its exact composition, it can be a sticky, black liquid or an apparently solid mass that behaves as a liquid over very large time scales. In American English, the m ...

oil shale Oil shale is an organic-rich Granularity, fine-grained sedimentary rock containing kerogen (a solid mixture of Organic compound, organic chemical compounds) from which liquid hydrocarbons can be produced. In addition to kerogen, general compos ...

and evaporite deposits within its centre, thick basin-margin limestone and dolomite, and the development of extensive

reef A reef is a ridge or shoal of rock, coral, or similar relatively stable material lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic component, abiotic (non-living) processes such as deposition (geol ...

s that ringed the basin margins that were tectonically uplifted as the basin subsided. During Middle Silurian times, subsidence ceased and this basin was uplifted. It generated an emergent arch, on which reefs grew, that divided the basin into eastern and western sub-basins. During the

Devonian The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian per ...

Period, this basin filled with terrestrial

red beds Red beds (or redbeds) are sedimentary rocks, typically consisting of sandstone, siltstone, and shale, that are predominantly red in color due to the presence of ferric oxides. Frequently, these red-colored sedimentary strata locally contain t ...

that interfinger with marine limestone and dolomites. Before deposition was terminated by marine regression, Upper Devonian black bituminous shale accumulated in the south-east of the basin. The remaining history of the Hudson Bay basin is largely unknown as a major

unconformity An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval ...

separates Upper Devonian strata from glacial deposits of the

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

. Except for poorly known terrestrial Cretaceous fluvial sands and gravels that are preserved as the fills of a ring of subsided strata around the centre of this basin, strata representing this period of time are absent from the Hudson Bay basin and the surrounding Canadian Shield. The Precambrian Shield underlying Hudson Bay and in which Hudson Bay basin formed is composed of two

Archean The Archean ( , also spelled Archaean or Archæan), in older sources sometimes called the Archaeozoic, is the second of the four geologic eons of Earth's history of Earth, history, preceded by the Hadean Eon and followed by the Proterozoic and t ...

proto-continents, the Western Churchill and Superior cratons. These

craton A craton ( , , or ; from "strength") is an old and stable part of the continental lithosphere, which consists of Earth's two topmost layers, the crust and the uppermost mantle. Having often survived cycles of merging and rifting of contine ...

s are separated by a tectonic collage that forms a suture zone between these cratons and the Trans-Hudson Orogen. The Western Churchill and Superior cratons collided at about 1.9–1.8 Ga in the Trans-Hudson orogeny. Because of the irregular shapes of the colliding cratons, this collision trapped between them large fragments of juvenile crust, a sizable

microcontinent Continental crustal fragments, partly synonymous with microcontinents, are pieces of continents that have broken off from main continental masses to form distinct islands that are often several hundred kilometers from their place of origin. Caus ...

, and

island arc Island arcs are long archipelago, chains of active volcanoes with intense earthquake, seismic activity found along convergent boundary, convergent plate tectonics, tectonic plate boundaries. Most island arcs originate on oceanic crust and have re ...

terrane In geology, a terrane (; in full, a tectonostratigraphic terrane) is a crust fragment formed on a tectonic plate (or broken off from it) and accreted or " sutured" to crust lying on another plate. The crustal block or fragment preserves its d ...

s, beneath what is now the centre of modern Hudson Bay as part of the Trans-Hudson Orogen. The Belcher Islands are the eroded surface of the Belcher Fold Belt, which formed as a result of the tectonic compression and folding of sediments that accumulated along the margin of the Superior Craton before its collision with the Western Churchill Craton.Darbyshire, F.A., and Eaton, D.W., 2010. ''The lithospheric root beneath Hudson Bay, Canada from Rayleigh wave dispersion: No clear seismological distinction between Archean and Proterozoic mantle'', ''Lithos''. 120(1–2), 144–159, doi:10.1016/j.lithos.2010.04.010.Eaton, D.W., and Darbyshire, F., 2010. ''Lithospheric architecture and tectonic evolution of the Hudson Bay region'', ''Tectonophysics''. 480(1–4), 1–22, doi:10.1016/j.tecto.2009.09.006.

Free-air gravity anomaly

Hudson Bay and the associated structural basin lie within the centre of a large free-air gravity anomaly that lies within the Canadian Shield. The similarity in areal extent of the free-air gravity anomaly with the perimeter of the former Laurentide ice sheet that covered this part of

Laurentia Laurentia or the North American craton is a large continental craton that forms the Geology of North America, ancient geological core of North America. Many times in its past, Laurentia has been a separate continent, as it is now in the form of ...

led to a long-held conclusion that this perturbation in the Earth's gravity reflected still ongoing glacial isostatic adjustment to the melting and disappearance of this ice sheet. Data collected over Canada by the

Gravity Recovery and Climate Experiment The Gravity Recovery and Climate Experiment (GRACE) was a joint mission of NASA and the German Aerospace Center (DLR). Twin satellites took detailed measurements of Earth's gravity field anomalies from its launch in March 2002 to the end of it ...

(GRACE) satellite mission allowed geophysicists to isolate the gravity signal associated with glacial isostatic adjustment from longer–time scale process of

mantle convection Mantle convection is the very slow creep of Earth's solid silicate mantle as convection currents carry heat from the interior to the planet's surface. Mantle convection causes tectonic plates to move around the Earth's surface. The Earth's l ...

occurring beneath the Canadian Shield. Based upon this data, geophysicists and other Earth scientists concluded that the Laurentide Ice Sheet was composed of two large domes to the west and east of Hudson Bay. Modelling glacial isostatic adjustment using the GRACE data, they concluded that ≈25 to ≈45% of the observed free-air gravity anomaly was due to ongoing glacial isostatic adjustment, and the remainder likely represents longer time-scale effects of mantle convection.Tamisiea, M.E., Mitrovica, J.X. and Davis, J.L., 2007. ''GRACE gravity data constrain ancient ice geometries and continental dynamics over Laurentia''. ''Science'', 316(5826), pp. 881–883.

Southeastern semicircle

Earth scientists have disagreed about what created the semicircular feature known as the Nastapoka arc that forms a section of the shoreline of southeastern Hudson Bay. The Nastapoka arc forms a 155 degree curve and appears to be very circular. Noting the paucity of impact structures on Earth in relation to the Moon and Mars, Carlyle S. BealsBeals, C.S., 1968. ''On the possibility of a catastrophic origin for the great arc of eastern Hudson Bay.'' In: Beals, C.S. (Ed.), pp. 985–999. ''Science, History and Hudson Bay'', Vol. 2, Department of Energy Mines and Resources, Ottawa. proposed that it is possibly part of a

Precambrian The Precambrian ( ; or pre-Cambrian, sometimes abbreviated pC, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of t ...

extraterrestrial impact structure that is comparable in size to the

Mare Crisium Mare Crisium (Latin ''crisium'', the "Sea of Crises") is a lunar mare located in the Moon's Crisium basin, just northeast of Mare Tranquillitatis. Mare Crisium is a basin of Nectarian age. It was formed by the flooding of basaltic lava that fill ...

on the Moon. In the same volume,

John Tuzo Wilson John Tuzo Wilson (October 24, 1908 – April 15, 1993) was a Canadian geophysicist and geologist who achieved worldwide acclaim for his contributions to the theory of plate tectonics. He added the concept of ''hot spots'', a volcanic region hott ...

Wilson, J.T., 1968. ''Comparison of the Hudson Bay arc with some other features.'' In: Beals, C.S. (Ed.), pp. 1015–1033. ''Science, History and Hudson Bay'', Vol. 2. Department of Energy Mines and Resources, Ottawa. commented on Beals' interpretation and alternately proposed that the Nastapoka arc may have formed as part of an extensive Precambrian continental collisional

orogen An orogenic belt, orogen, or mobile belt, is a zone of Earth's crust affected by orogeny. An orogenic belt develops when a continental plate crumples and is uplifted to form one or more mountain ranges; this involves a series of geological proc ...

, linked to the closure of an ancient

ocean basin In hydrology, an oceanic basin (or ocean basin) is anywhere on Earth that is covered by seawater. Geologically, most of the ocean basins are large  geologic basins that are below sea level. Most commonly the ocean is divided int ...

. The current general consensus is that it is an arcuate boundary of tectonic origin between the Belcher Fold Belt and undeformed basement of the Superior Craton created during the Trans-Hudson orogeny. This is because no credible evidence for such an impact structure has been found by regional magnetic, Bouguer gravity, or other geologic studies. However, other Earth scientists have proposed that the evidence of an Archean impact might have been masked by deformation accompanying the later formation of the Trans-Hudson orogen and regard an impact origin as a plausible possibility.Goodings, C.R. & Brookfield, M.E., 1992. ''Proterozoic transcurrent movements along the Kapuskasing lineament (Superior Province, Canada) and their relationship to surrounding structures.'' ''Earth-Science Reviews'', 32: 147–185.Bleeker, W., and Pilkington, M., 2004. ''The 450-km-diameter Nastapoka Arc: Earth's oldest and largest preserved impact scar?'' ''Program with Abstracts – Geological Association of Canada; Mineralogical Association of Canada: Joint Annual Meeting, 2004'', Vol. 29, pp. 344.

Economy

Arctic Bridge

The longer periods of ice-free navigation and the reduction of Arctic Ocean ice coverage have led to Russian and Canadian interest in the potential for commercial trade routes across the Arctic and into Hudson Bay. The so-called Arctic Bridge would link Churchill, Manitoba, and the Russian port of

Murmansk Murmansk () is a port city and the administrative center of Murmansk Oblast in the far Far North (Russia), northwest part of Russia. It is the world's largest city north of the Arctic Circle and sits on both slopes and banks of a modest fjord, Ko ...

. The increase in ships traversing the proposed Arctic Bridge could result in an increase in accidents. Any pollutants released into the environment would be harder to remove as the cleanup would be complicated by ice sheets.

Port

The biggest port in the Hudson bay is the city of Churchill, which lies on the river with the same name, Churchill River. The Port of Churchill is a privately owned

port A port is a maritime facility comprising one or more wharves or loading areas, where ships load and discharge cargo and passengers. Although usually situated on a sea coast or estuary, ports can also be found far inland, such as Hamburg, Manch ...

on Hudson Bay in Churchill, Manitoba, Canada. Routes from the port connect to the

North Atlantic The Atlantic Ocean is the second largest of the world's five oceanic divisions, with an area of about . It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for ...

through the

. As of 2008, the port had four deep-sea berths capable of handling

Panamax Panamax and New Panamax (or Neopanamax) are terms for the size limits for ships traveling through the Panama Canal. The limits and requirements are published by the Panama Canal Authority (ACP) in a publication titled "Vessel Requirements". ...

-size vessels for the loading and unloading of grain, bulk commodities, general cargo, and tanker vessels. The port is connected to the Hudson Bay Railway, which shares the same parent company, and cargo connections are made with the

Canadian National Railway The Canadian National Railway Company () is a Canadian Class I freight railway headquartered in Montreal, Quebec, which serves Canada and the Midwestern and Southern United States. CN is Canada's largest railway, in terms of both revenue a ...

system at HBR's southern terminus in

The Pas The Pas ( , ) is a town in Manitoba, Canada, at the confluence of the Pasquia River and the Saskatchewan River and surrounded by the unorganized Northern Region of the province. It is approximately northwest of the provincial capital, Winn ...

. It is the only port of its size and scope in Canada that does not connect directly to the country's road system; all goods shipped overland to and from the port must travel by rail. The port was built and owned by the

Government of Canada The Government of Canada (), formally His Majesty's Government (), is the body responsible for the federation, federal administration of Canada. The term ''Government of Canada'' refers specifically to the executive, which includes Minister of t ...

, but was sold in 1997 to the American company

to run privately. In December 2015, OmniTRAX announced it was negotiating a sale of the port, and the associated Hudson Bay Railway, to a group of

based in northern Manitoba. With no sale finalized by July 2016, OmniTRAX shut down the port and the major railroad freight operations in August 2016. The railway continued to carry cargo to supply the town of Churchill itself until the line was damaged by flooding on 23 May 2017. The Port and the Hudson Bay Railway were sold to Arctic Gateway Group—a consortium of First Nations, local governments, and corporate investors—in 2018. On 9 July 2019, ships resupplying Arctic communities began stopping at the port for additional cargo, and the port began shipping grain again on 7 September 2019.

Coastal communities

The coast of Hudson Bay is extremely sparsely populated; there are only about a dozen communities. Some of these were founded as trading posts in the 17th and 18th centuries by the Hudson's Bay Company, making them some of the oldest settlements in

Western Canada Western Canada, also referred to as the Western provinces, Canadian West, or Western provinces of Canada, and commonly known within Canada as the West, is a list of regions of Canada, Canadian region that includes the four western provinces and t ...

. With the closure of the HBC posts and stores, although many are now run by The North West Company, in the second half of the 20th century, many coastal villages are now almost exclusively populated by

and

Inuit Inuit (singular: Inuk) are a group of culturally and historically similar Indigenous peoples traditionally inhabiting the Arctic and Subarctic regions of North America and Russia, including Greenland, Labrador, Quebec, Nunavut, the Northwe ...

. Two main historic sites along the coast were

and Prince of Wales Fort. Communities along the Hudson Bay coast or on islands in the bay are (all populations are as of 2016): * Nunavut **

, population 2,657 ** Chesterfield Inlet, population 437 ** Coral Harbour, population 891 ** Rankin Inlet, population 2,842 ** Sanikiluaq, population 882 ** Whale Cove, population 435 * Manitoba ** Churchill, population 899 * Ontario ** Fort Severn First Nation, population 361 * Quebec ** Akulivik, population 633 ** Inukjuak, population 1,757 ** Kuujjuarapik, population 686 ** Puvirnituq, population 1,779 ** Umiujaq, population 442 **

Whapmagoostui Whapmagoostui (, "place of the beluga") is the northernmost Cree village in Quebec, Canada, located at the mouth of the Great Whale River () on the coast of Hudson Bay in Nunavik. About 906 Cree with about 650 Inuit, living in the neighbourin ...

, population 984

Military development

The

built forts as fur trade strongholds against the French or other possible invaders. One example is

with angled walls to help defend the fort. In the 1950s, during the

Cold War The Cold War was a period of global Geopolitics, geopolitical rivalry between the United States (US) and the Soviet Union (USSR) and their respective allies, the capitalist Western Bloc and communist Eastern Bloc, which lasted from 1947 unt ...

, a few sites along the coast became part of the Mid-Canada Line, watching for a potential Soviet bomber attack over the North Pole. The only Arctic deep-water port in Canada is the Port of Churchill, located at Churchill, Manitoba.

Notes

References

General sources

* ''Atlas of Canada''
online version
* Some references of geological/impact structure interest include: ** Rondot, Jehan (1994). "Recognition of eroded astroblemes". ''Earth-Science Reviews'' 35, 4, pp. 331–365. ** Wilson, J. Tuzo (1968). "Comparison of the Hudson Bay arc with some other features". In: ''Science, History and Hudson Bay'', v. 2. Beals, C. S. (editor), pp. 1015–1033. *

External links

* {{Authority control Borders of Nunavut Landforms of Nord-du-Québec Bodies of water of Manitoba Bodies of water of Kivalliq Region Bodies of water of Qikiqtaaluk Region Bays of Ontario Bays of Quebec Bodies of water of the Atlantic Ocean Seas of the Arctic Ocean Seas of Canada Bays of Nunavut

Description

History

Geography and climate

Extent

Climate

Waters

Shores

Islands

Geology

Free-air gravity anomaly

Southeastern semicircle

Economy

Arctic Bridge

Port

Coastal communities

Military development

See also

Notes

References

General sources

External links