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Home , Hudson Bay, Hudson Bay Lowlands, Hudson Strait

662 Hudson swamp life, because of their ability to adapt to the NatureWorks. “Swamps.” New Hampshire Public changing environment,and to take advantage of a Television, 2012. http://www.nhptv.org/nature range of water levels. Fish here include largemouth works/nwep7i.htm. bass, bluegill, warmouth, red-ear sunfish, alligator Nickell, Joe. “Tracking the Swamp Monsters.” gar, freshwater drum, flathead catfish, and buffalo Committee for Skeptical Inquiry 25, no. 4 (2001). fish. Enormous quantities of crawfish thrive in Honey Island Swamp.

Human Impact In 1980, President Jimmy Carter authorized the 37,000-acre (15,000-hectare) Bogue Chitto National Wildlife Refuge (NWR), located north of and adja- Category: Marine and Oceanic Biomes. cent to Honey Island Swamp. The swamp is now a Geographic Location: . permanently protected wildlife area under the con- Summary: The second-largest bay in the world, trol of this refuge, and managed by the Louisiana Hudson Bay supports diverse cold-water coastal Department of Wildlife and Fisheries. A larger part and marine ecosystems. of the swamp is claimed as the Pearl Wildlife Management Area (WMA). The Pearl River WMA, Named for the Dutch explorer , at 35,000 acres (14,000 hectares), is comparable to Hudson Bay is the second-largest bay in the world, the Bogue Chitto NWR in size. after the . It is a marine bay and mar- Honey Island Swamp remains intact except for ginal in northern that drains most of its waterways. The swamp is accessible only by the central area of the country as well as parts of boat or on foot; few roads exist in the area, and the upper Midwest of the United States, about 1.5 none within the borders of the swamp. As desig- million square miles (3.9 million square kilome- nated by the Nature Conservancy, Honey Island ters) in all. The Hudson connects with the North Swamp is Louisiana’s first Nature Preserve (with Atlantic via the , and to the the pine forests of the northern portion of the Ocean via the Northwest Passages. area controlled by the Bogue Chitto NWR). This ecosystem provides habitat and food sources for and the surrounding plant and animal life, water pre- Many streams and contribute to its waters, serves, water filtering, spawning and fishing areas, but not nearly enough to offset its brackish salin- as well as flood control from major storm surges. ity. Hudson Bay is surrounded by vast expanses of Global warming poses a real and growing threat , shrubland steppes, or boreal for- to the Honey Island Swamp biome, in particular est, and ecosystems. from the projected impact of sea-level rise. At the Hudson Bay is a relatively shallow saltwa- most pessimistic estimates, the swamp could remain ter body, with an average depth of 330 feet (100 substantially inundated, such that areas today fed meters). It is about 900 miles (1,450 kilometers) and refreshed by tidal flows would become entirely long north to south—including its southernmost different, permanently submerged habitats. Saltwa- lobe, —and about 650 miles (1,050 kilo- ter intrusion, and its habitat-changing dynamic, is meters) across at its widest. Total surface area is an associated impact risk that seems imminent. approximately 450,000 square miles (1.16 million square kilometers). Hudson Bay is ice-covered for Sandy Costanza half the year; ice begins to form in early November, and the whole bay has very low year-round aver- Further Reading age temperatures. The ice cover begins to melt in Keddy, Paul A. Water, , Fire: Louisiana’s Natural mid-June, usually clearing from the eastern shores Heritage. Bloomington, IN: Xlibris, 2008. first. Water temperature rises to 46–48 degrees F Hudson Bay 663

(8 to 9 degrees C) on the western side of the bay intertidal, and habitats here. Most such by late summer. species—at least 100—find breeding zones on While it is a saltwater or brackish body, Hud- shore. Cranes, plovers, herons, bitterns, loons, son Bay receives freshwater inflow at an annual pelicans, ducks, geese, swans, osprey, falcons, volume of some 170 cubic miles (700 cubic kilo- eagles, and owls share the Hudson. meters); even more comes from and Less is known about the prevalence and range ice melt. Consequently, and also due to its limited of marine fish species here, due to the near- hydraulic exchange with the Atlantic, the bay is absence of commercial fisheries; even traditional less salty than the ocean. subsistence fishing has been somewhat limited. Some 60 or so fish species are known in these Rich Base of Life waters, however, and many of these are adapted to Because of its vast dimensions, the Hudson Bay the relatively shallow, brackish environment here. marine ecosystem has many aquatic and coastal Of the recognized species, about two dozen stay ecozones with varied habitats that are used year- in the marine environment all their lives; half that round by Arctic and sub-Arctic species, as well as many species are marine but frequent the estu- seasonally by migratory fish, marine mammals, aries as seasonal nursery grounds; another nine and birds. The , for instance, supports the feed in the brackish coastal realm, but spawn in seals upon which polar bears depend. Millions of freshwater zones; as many as 16 freshwater spe- geese and shorebirds feed and breed in vast salt cies have evolved salinity tolerances sufficient to marshes. Productive submarine eelgrass beds spend some time here in brackish coastal reaches provide food for waterfowl migrating to and from or estuaries; and one—the Atlantic salmon—win- breeding habitat in the Arctic Islands, and shelter ters in saltwater in between the freshwater spawn for crustacean and fish populations. Numerous and final act of its anadromous life cycle. estuaries provide habitat corridors for anadro- mous fish like salmon and Arctic char, and sup- Conservation and Climate Change beluga whales. The governance of the Hudson Bay area is largely The Hudson Bay supports great numbers of a series of compromise decisions and shared large mammals, both aquatic and terrestrial. responsibilities between federal, provincial, local, Migratory species such as belu- and bodies. As global warming gas, , and bowhead whales frequent the proceeds—and faster here in its effects than in as permitted by ice conditions across the many if not most other parts of the world—such northern channels. Other cetaceans, such as orca organizations will have to work more closely in and minke whales, are rarer visitors. Large con- concert to help determine the growing number centrations of up to 20,000 beluga whales are of issues. These will range from plans for hydro- found in the estuaries of the Nelson and Churchill electric dams and other water diversion schemes; Rivers in July and August. new deepwater port facilities and related marine Ringed seals, bearded seals, and harbor seals, as transport strategies; mining, agriculture, grazing, well as walruses, reside in the bay year-round, while and aquaculture rights; tourism pursuits such as harp and hooded seals visit seasonally. Subsistence hunting; real estate development; and encompass- harvesting of these marine mammals is important ing all of these areas: conservation. to the aboriginal peoples and the economy of the There has already been considerable focus on bay. Arctic foxes and polar bears reside on coasts the impact of climate change and transboundary in the summer, and on sea ice during the rest of contaminants on Hudson bay. Historic commer- the year; they, too, are hunters of the seals. cial , particularly for bowheads and belu- At least 130 species of birds migrate to the Hud- gas, depleted these populations, some of which son’s waters each summer, and depart in late fall. have not entirely recovered. The steady increase in Waders, water fowl, and raptors share pelagic, regional temperatures over the last 100 years has 664 caused a lengthening of the ice-free period, and the southern shores of Hudson and James Bays. continues to jeopardize the sustainability of ice- Encompassing parts of the Canadian provinces dependent species such as polar bears and seals. of , , and , the lowlands These ice-dependent marine mammals are vul- are along the ecotone (overlap) between the boreal nerable to both airborne contaminants and global forest to the south and Arctic tundra to the north. warming. Because these carnivorous animals are The area faces significant change, however, from high in the food chain, they accumulate contami- the effects of climate change as well as isostatic nants such as heavy metals, carcinogenic hydro- rebound (rising ground elevation) of a landscape carbons, and radioactive materials in their fatty once burdened by the fantastic weight of continen- and other tissues. tal, ice-age . Diminished sea-ice cover, decreasing flow from The location of Hudson Bay and the lowlands its tributary rivers, and increasing precipitation to its southwest and south, correspond with the are some of the long-term trends already detected approximate center of the — in the Hudson Bay; each of these vectors is pro- the massive ice load that covered North America jected to intensify, along with other effects such as during the period, before it retreated sea-level rise, that will have as yet undetermined and melted some 20,000 years ago. The mas- but certainly serious impacts on the habitats here. sive weight of that ice, which was as much as two miles thick, compressed the ground below, allow- Magdalena A. K. Muir ing incursion of salt water in areas far beyond the current shores of Hudson Bay. In addition, the ice Further Reading scoured the ground beneath it, effectively bulldoz- Ferguson, Steve H., Lisa L. Loseto, and Mark L. ing or filling in the original drainage network and Mallory, eds. A Little Less Arctic: Top Predators in ensuring, because of that disrupted drainage, that the World’s Largest Northern , Hudson large swaths of the region would remain wet and Bay. New York: Springer, 2010. bogged down after the glaciers retreated. Ritchie, J. C. Postglacial Vegetation of Canada. The landforms left behind include gravel ridges Cambridge, MA: Cambridge University Press, 1987. and hills—usually derived from glacial deposits— Stewart, D. B. and W. L. Lockhart. “An Overview of raised beaches, occasional rocky outcrops, per- the Hudson Bay Marine Ecosystem.” Fisheries and mafrost hummocks, and extensive lowlands filled Canada, 2005. http://www.dfo-mpo.gc.ca/ with glacial or marine sediments. Upland areas are libraries-bibliotheques/toc-tdm/314704-eng.htm. often dominated by boreal forest vegetation, in par- ticular white spruce—one of the dominant species of the North American boreal forest—with balsam fir, quaking aspen, balsam poplar, and paper birch. Important plant associates include dogwood, wil- Hudson Bay Lowlands low, lingonberry, bearberry, twinflower, miterwort, false toadflax, wintergreen, or mosses such asHylo - Category: Forest Biomes. comium or Pleurozium. Stands of black spruce and Geographic Location: Canada. jack pine may also be important components of the Summary: The Hudson Bay Lowlands biome is forests of upland sites. the largest wetlands in North America, but the region faces significant changes as a result of Lowland and Wetland Types isostatic rebound and climate change. The type of lowland sites are influenced in large part by site conditions. Tundra, dominated by The Hudson Bay lowlands are the largest wetland shrubs such as blueberry, lingonberry, bearberry, area in North America, covering a vast expanse and lichens such as Cladonia, occurs in relatively of Canada between the and well-drained sites in a strip along the Hudson and