The Yukon River is a major watercourse of northwestern North America. From its source in British Columbia, it flows through Canada's territory of Yukon. The lower half of the river continues westward through the U.S. state of Alaska. The river is 3,190 kilometres (1,980 mi) long and empties into the Bering Sea at the Yukon–Kuskokwim Delta. The average flow is 6,400–7,000 m3/s (230,000–250,000 cu ft/s). The total drainage area is 854,700 km2 (330,000 sq mi), of which 323,800 km2 (125,000 sq mi) lies in Canada. The total area is more than 25% larger than Texas or Alberta.
Salmon is the common name for several commercially important species of euryhaline ray-finned fish from the genera Salmo and Oncorhynchus of the family Salmonidae, native to tributaries of the North Atlantic (Salmo) and North Pacific (Oncorhynchus) basins. Other closely related fish in the same family include trout, char, grayling, whitefish, lenok and taimen, all coldwater fish of the subarctic and cooler temperate regions with some sporadic endorheic populations in Central Asia.
The Arctic National Wildlife Refuge or Arctic Refuge is a national wildlife refuge in northeastern Alaska, United States, on traditional Iñupiaq and Gwich'in lands. The refuge is 19,286,722 acres (78,050.59 km2) of the Alaska North Slope region, with a northern coastline and vast inland forest, taiga, and tundra regions. ANWR is the largest national wildlife refuge in the country, slightly larger than the Yukon Delta National Wildlife Refuge. The refuge is administered from offices in Fairbanks. ANWR is home to a diverse range of endemic mammal species; notably, it is one of the few North American locations with all three endemic American bears—the polar bear, grizzly bear, and American black bear, each of which resides predominantly in its own ecological niche. Besides the bears, other mammal species include the moose, caribou, wolves, red and Arctic fox, Canada lynx, wolverine, pine marten, American beaver, and North American river otter. Further inland, mountain goats may be seen near the slope. Hundreds of species of migratory birds visit the refuge yearly, and it is a vital, protected breeding location for them. Snow geese, eiders and snowy owls may be observed as well.
The Mackenzie River is a river in the Canadian boreal forest. It forms, along with the Slave, Peace, and Finlay, the longest river system in Canada, and includes the second largest drainage basin of any North American river after the Mississippi.
The Kobuk River, also known by the names Kooak, Kowak, Kubuk, Kuvuk, and Putnam, is a river located in the Arctic region of northwestern Alaska in the United States. It is approximately 280 miles (451 km) long. Draining a basin with an area of 12,300 square miles (32,000 km2), the Kobuk River is among the largest rivers in northwest Alaska, with widths of up to 1,500 feet and flows reaching speeds of 3–5 miles per hour in its lower and middle reaches. The average elevation for the Kobuk River Basin is 1,300 feet (400 m) above sea level, ranging from sea level at its mouth on the Bering Sea to 11,400 feet near its headwaters in the Brooks Range.
The Stikine River is a major river in northern British Columbia (BC), Canada and southeastern Alaska in the United States. It drains a large, remote upland area known as the Stikine Country east of the Coast Mountains. Flowing west and south for 610 kilometres (379 mi), it empties into various straits of the Inside Passage near Wrangell, Alaska. About 90 percent of the river's length and 95 percent of its drainage basin are in Canada. Considered one of the last truly wild large rivers in BC, the Stikine flows through a variety of landscapes including boreal forest, steep canyons and wide glacial valleys.
A salmon run is an annual fish migration event where many salmonid species, which are typically hatched in fresh water and live most of the adult life downstream in the ocean, swim back against the stream to the upper reaches of rivers to spawn on the gravel beds of small creeks. After spawning, all species of Pacific salmon and most Atlantic salmon die, and the salmon life cycle starts over again with the new generation of hatchlings.
The Chinook salmon is the largest and most valuable species of Pacific salmon. Its common name is derived from the Chinookan peoples. Other vernacular names for the species include king salmon, Quinnat salmon, Tsumen, spring salmon, chrome hog, Blackmouth, and Tyee salmon. The scientific species name is based on the Russian common name chavycha (чавыча).
The term freshet is most commonly used to describe a snowmelt, an annual high water event on rivers resulting from snow and river ice melting.
The Yolo Bypass is one of the two flood bypasses in California's Sacramento Valley located in Yolo and Solano Counties. Through a system of weirs, the bypass diverts floodwaters from the Sacramento River away from the state's capital city of Sacramento and other nearby riverside communities.
Puget Sound salmon recovery is a collective effort of federal, state and local authorities and non-profit coalitions of universities, scientists, business and industry aimed at restoring Pacific salmon and anadromous forms of Pacific trout (Oncorhynchus) within the Puget Sound region. The Puget Sound lies within the native range of the Pacific Salmon (Oncorhynchus) and two sea-run forms of Pacific trout, the coastal rainbow trout or steelhead and coastal cutthroat trout. Populations of Oncorhynchus have seen significant declines since the middle of the 19th century due to over fishing, habitat loss, pollution and disease. Salmon species residing in or migrating through the Puget Sound to spawning streams include Chum, Coho, Chinook, Sockeye, and Pink salmon. Pacific salmon require freshwater rivers for spawning and most major tributaries of the Puget Sound have salmon, steelhead and cutthroat trout spawning runs.
Yukon is in the northwestern corner of Canada and is bordered by Alaska, British Columbia and the Northwest Territories. The sparsely populated territory abounds with natural scenery, snowmelt lakes and perennial white-capped mountains, including many of Canada's highest mountains. The territory's climate is Arctic in territory north of Old Crow, subarctic in the region, between Whitehorse and Old Crow, and humid continental climate south of Whitehorse and in areas close to the British Columbia border. Most of the territory is boreal forest with tundra being the main vegetation zone only in the extreme north and at high elevations.
Aufeis is a sheet-like mass of layered ice that forms from successive flows of ground or river water during freezing temperatures. This form of ice is also called overflow, icings, or the Russian term, naled. The term "Aufeis" was first used in 1859 by Alexander von Middendorff following his observations of the phenomenon in northern Siberia.
A boreal ecosystem is an ecosystem with a subarctic climate located in the Northern Hemisphere, approximately between 50° and 70°N latitude. These ecosystems are commonly known as taiga and are located in parts of North America, Europe, and Asia. The ecosystems that lie immediately to the south of boreal zones are often called hemiboreal. There are a variety of processes and species that occur in these areas as well.
Kanuti National Wildlife Refuge is a national wildlife refuge in central Alaska, United States. One of 16 refuges in Alaska, it was established in 1980 when Congress passed The Alaska National Interest Lands Conservation Act (ANILCA). At 1,640,000 acres (6,600 km2), Kanuti Refuge is about the size of the state of Delaware. Located at the Arctic Circle, the refuge is a prime example of Alaska's boreal ecosystem. It is dominated by black and white spruce, with some white birch and poplars.
The Koyukuk National Wildlife Refuge is a 3,500,000-acre (14,000 km2) conservation area in Alaska. It lies within the floodplain of the Koyukuk River, in a basin that extends from the Yukon River to the Purcell Mountains and the foothills of the Brooks Range. This region of wetlands is home to fish, waterfowl, beaver and Alaskan moose, and wooded lowlands where two species of fox, bears, wolf packs, Canadian lynx and marten prowl.
The North American Arctic is composed of the northern polar regions of Alaska (USA), Northern Canada and Greenland. Major bodies of water include the Arctic Ocean, Hudson Bay, the Gulf of Alaska and North Atlantic Ocean. The North American Arctic lies above the Arctic Circle. It is part of the Arctic, which is the northernmost region on Earth. The western limit is the Seward Peninsula and the Bering Strait. The southern limit is the Arctic Circle latitude of 66° 33’N, which is the approximate limit of the midnight sun and the polar night.
Salmon population levels are of concern in the Atlantic and in some parts of the Pacific. Salmon are typically anadromous - they rear and grow in freshwater, migrate to the ocean to reach sexual maturity, and then return to freshwater to spawn. Determining how environmental stressors and climate change will affect these fisheries is challenging due to their lives split between fresh and saltwater. Environmental variables like warming temperatures and habitat loss are detrimental to salmon abundance and survival. Other human influenced effects on salmon like overfishing and gillnets, sea lice from farm raised salmon, and competition from hatchery released salmon have negative effects as well.
The Hudson Plains Ecoregion is a vast, flat, and waterlogged landscape. This ecoregion covers a 369,000 square kilometer area along the south shoreline of the Hudson Bay, which includes the Canadian provinces of Eastern Quebec, Northern Ontario and Western Manitoba. Because of the location of the ecoregion, winter prevails for many months of the year and rising temperatures, along with melting ice, makes fog common. The short summers provide a home for thousands of migrating birds. The region is used by humans for its mineral resources and hydroelectric power as a result of the abundance of water and emergent societal needs. Though relatively uninhabited and undisturbed, the natural resources of the Hudson Plains are still subject to anthropogenic activities. Its climatic, geographic, and evolutionary patterns categorize it as one of many ecoregions in North America.
The Northwestern Forested Mountains is a Level I ecoregion of North America designated by the Commission for Environmental Cooperation (CEC) in its North American Environmental Atlas.
