Baffin Bay (biome)
Baffin Bay is a crucial Arctic marine biome located between Canada’s Nunavut Province and Greenland, encompassing an area of approximately 300,000 square miles (775,000 square kilometers). The bay is characterized by extensive sea ice that persists for over nine months each year, with areas known as polynyas providing vital open water that supports diverse marine life. Notably, the North Water polynya is one of the largest in the world, facilitating a rich ecosystem where species such as Arctic cod play a critical role as a food source for various marine mammals including beluga whales, polar bears, and seals.
The surrounding coastal regions feature Arctic tundra, with vegetation adapted to harsh conditions. Baffin Bay is also home to significant seabird populations, particularly in protected areas like Sirmilik National Park and several wildlife reserves. These habitats are essential for breeding and foraging, supporting large colonies of seabirds like thick-billed murres and black-legged kittiwakes.
Despite its remote setting, Baffin Bay faces development pressures, including proposed mining projects which raise concerns about environmental sustainability. The effects of climate change are evident, with melting ice impacting the habitat of polar bears and altering ecological dynamics. Conservation efforts are underway to balance human activity with the protection of this unique Arctic ecosystem, highlighting the importance of Baffin Bay in global marine biodiversity and climate resilience.
Baffin Bay (biome)
Category: Marine and Oceanic Biomes.
Geographic Location: North America.
Summary: Bordered by Canada's Nunavut Province on the west and Kalaallit Nunaat (Greenland) on the east, Baffin Bay is known for its marine mammals, seabirds, and polar bears.
Baffin Bay is positioned to the northwest of the North Atlantic Ocean, straddles the Arctic Circle, and features a surface-frozen channel that connects to the Arctic Sea. The bay, with a surface area of approximately 300,000 square miles (775,000 square kilometers), is cradled between two giant boreal islands: to the west, Baffin Island, within the Canadian province of Nunavut; to the east, Greenland. To the north is a third major island, Ellesmere; between it and Greenland the relatively constricted chain of Smith Sound–Kane Basin–Kennedy Channel–Hall Basin–Robeson Channel, together known as Nares Strait, forms a roughly 350-mile-long (565-kilometer-long) link to the Arctic Sea. To the south, the broader Davis Strait opens upon the Labrador Sea, itself a lobe of the North Atlantic.
Much of Baffin Bay is jammed with sea ice more than nine months of the year, but the biome features some polynyas, or areas of seasonal open water surrounded by pack ice, that provide oases for life adapted to the Arctic cold. The most important of these is called the North Water. A mighty polynya considered one of the world's largest, the North Water, extends across as much as 33,000 square miles (85,000 square kilometers) of northern Baffin Bay and Smith Sound late each spring. Heavy ice floes from the Arctic are blocked at this time of year by an ice arch that forms across the southern aperture of the Kane Basin.
The West Greenland Current, sweeping northward out of the Atlantic and along the Greenland coast until it enters the North Water, is somewhat saltier and warmer than the prevailing Baffin Bay waters. This helps make North Water a haven for marine life in the bay. Currents generally arc east to west through North Water, then the Baffin Island Current heads south to help generate the southeasterly Labrador Current into the North Atlantic. Thus the macrocirculation picture in Baffin Bay is counterclockwise: north along Greenland and south along Baffin Island.
Biota
Arctic tundra borders the bay in narrow coastal plains and rockbound pockets on Baffin Island and stretches of the Greenland coast. Characteristic vegetation runs from stunted stands of salt-tolerant willow and alder to a relative abundance of flowering plants such as woodrush (Juncaceae spp.), harebell (Campanula rotundifolia), and Arctic poppy (Papaver radicatum). The waters of the bay support vital algae colonies, especially pronounced in areas like Lancaster Sound (between Baffin and Ellesmere Islands) and North Water.
Arctic cod is a vital component of the ecosystem in Baffin Bay, as a prime food source for the vast marine mammal population. Humans, too, have long relied on the cod fishery of Baffin Bay and its associated inlets, sounds, and channels. Lancaster Sound alone is home to cod schools that have been estimated at up to 30,000 tons per school.
Protected Areas
Canada's Sirmilik National Park includes the Bylot Island Migratory Bird Sanctuary, adjoining Lancaster Sound near the northeastern tip of Baffin Island. Park authorities estimate up to 320,000 thick-billed murres and 50,000 black-legged kittiwakes, seabirds hailing from the North Atlantic, make use of the cliffs in spring, while nearby polynyas offer good foraging for both the seabirds and marine mammals. Another seabird, the northern fulmar, makes perhaps its largest Canadian colony at the Ellwin Inlet and Baillarge Bay areas of the park, nesting on cliffs 1,970 feet (600 meters) high. Eclipse Sound, another area of the park, is covered by ice until midsummer but offers prime habitat for narwhals and polar bears.
Besides the sanctuary on Bylot, there are five other reserves offering refuge to fowl, mammals, and other fauna around Baffin Bay. The northernmost is Nirjutiqavvik National Wildlife Area on Coburg Island, a nesting area for 385,000 birds including black-legged kittiwakes, thick-billed murre, northern fulmar, and black guillemot. Also present are polar bears, ringed seals, walruses, and narwhal and beluga whales. Cambridge Point on the island overlooks a polynya. To the southwest, on the western edge of Lancaster Sound, is Prince Leopold Island Migratory Bird Sanctuary; its vertical cliffs of sandstone and limestone rise to 820 feet (250 meters), providing additional nesting sites. Niginganiq (Iqaliqtuuq) National Wildlife Area includes summer habitat for a population of bowhead whales. Adults and adolescent whales frequent this area on the east coast of Baffin Island.
Akpait National Wildlife Area, located in southern Baffin Bay at the easternmost point of Baffin Island, includes Canada's largest thick-billed murre colonies, nesting black-legged kittiwakes, glaucous gulls, and black guillemots. Ocean cliffs here rise to 3,002 feet (915 meters), with polar bears and marine mammals active below. At nearby Qaqulluit National Wildlife Area, two rock towers rise 1,411 feet (430 meters) out of the ocean and host nesting northern fulmars. The surrounding waters are important for marine mammals.
Development and Sustainability
Despite the harsh climate, development is proposed in some areas of Baffin Bay. At the Mary River Project on Baffin Island, the Baffinland Iron Mines Corporation plans to develop an iron-ore mine. The minerals would be shipped via a new railroad south to the Foxe Basin. Seasonal access is also proposed at Milne Inlet, a southern extension of Baffin Bay known as Eclipse Sound, via a 62-mile mile (99-kilometer) haul road. The project is awaiting the approval of the Nunavut government.
In its Canadian territorial waters, Baffin Bay falls mainly within that government's Eastern Arctic bioregion and is part of one or more planned marine protected areas (MPA). The internationally recognized MPA designation attempts to frame and encourage such goals and measures as biological diversity, conservation, restoration, and integrated ocean management.
In 2009, authorities from Canada, Nunavut, and Greenland agreed on ordinances and enforcement aimed at protecting the polar bear population of Baffin Bay and Kane Basin; the bears are subject to pressures from human hunting, pollution, prey depletion, and global warming. Experts feared that melting sea ice might significantly reduce the polar bear population. However, when the ice melts in the mid- to late-summer, the bears move onto land. They have adapted to spend ninety days on land instead of sixty, as they did in the past. However, on land, polar bears have less to time to hunt seals and instead rely more on their fat reserves. This results in thinner bears with smaller litters. The polar bears in Baffin Bay continue to thrive, though, with a population of 2,800, which is larger than in the past.
Global warming is already affecting Baffin Bay, with major effects manifesting in obvious ways such as accelerated glacial melt from Greenland—adding to freshwater volume and altering the salinity balance—and in less predictable ways such as potential disruptions of the flow of higher-saline seawater from the Atlantic; greater algal blooms yielded by more open water; and increasing human industrial activity as ice-free sea channels expand to new areas and for longer periods each year, making oil drilling, shipping, and port facility development more feasible.
Bibliography
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McKinnon, L., et al. “Lower Predation Risk for Migratory Birds at High Latitudes.” Science 327, no. 5963 (2010).
Shubin, Neil. Your Inner Fish. New York: Random House, 2008.
Strong, Walter. "It's No Surprise for Inuit--Baffin Bay Polar Bears Defy Past Assumptions with Stable Population." CBC News, 3 Mar. 2020, www.cbc.ca/news/canada/north/baffin-bay-polar-bears-nunavut-1.5472492. Accessed 20 July 2022.
Tang, Charles C. L., Charles K. Ross, Tom Yao, Brian Petrie, Brendan M. DeTracey, and Ewa Dunlap. The Circulation, Water Masses, and Sea-Ice of Baffin Bay. Dartmouth, Canada: Bedford Institute of Oceanography, 2004.