Baffin Bay and Davis Strait are two large basins between Nunavut’s Baffin Island and Greenland that connect the Arctic Ocean with the Atlantic. Stretching over 1.1 million square kilometres (425,000 square miles), they make up an area that is more than four times bigger than the Great Lakes combined. The region includes the North Water Polynya, one of the Arctic’s largest open-water areas and one of the most biologically productive volumes of water in any polar region. The icy habitat of Baffin Bay and Davis Strait is an ideal home for globally important populations of bowhead whales, narwhals, fish, seabirds and cold water corals.
Corals and sponges in the Davis Strait
© Mountains in the Sea 2004. NOAA Office of Ocean Exploration; Dr. Les Watling, Chief Scientist, University of Maine
Marine Life
Baffin Bay’s estimated population of 50,000 narwhals accounts for 80 to 90 percent of the world’s population. Narwhals are year-round residents of Baffin Bay, feeding and mating in the winter. Swimming under the ice to depths of 1,500 to1,800 metres (5,000-6,000 feet), narwhal feed on turbot during the winter, surfacing at breathing holes, cracks and polynyas in the ice.
The region is also a refuge for the eastern population of bowhead whales. Hunted to the point of extinction in the Atlantic by European and American whalers, bowhead in Baffin Bay and Davis Strait are still listed as a threatened species. But Inuit have reported the population is increasing, an observation now confirmed by scientists. In the summer, bowheads live in shallow bays, sounds and fjords around Baffin and neighboring islands. As ice forms in the fall, the whales move to the open-water areas in polynyas and unconsolidated pack ice that they can break through with their large heads.
Western Baffin Bay is home to an estimated one million seabirds and millions more that visit to feed in the summer. The North Water Polynya in the northern part of Baffin Bay is a critical feeding area for an estimated two-thirds of the world population of dovekie and thick-billed murres that breed on adjacent shores.
Baffin Bay and Davis Strait provide habitat for 116 species of fish ranging from Arctic char, an important staple in the diet of Inuit in Nunavut, to deep water fish like turbot. Every year, turbot gather from Greenland, Newfoundland and Labrador to spawn in the deep waters. The capelin and herring populations of southern Davis Strait are important forage fishes.
Sun over ice
© Bruno Tremblay
Cold Water Coral
Breathtakingly bright forests of deep water corals live on the bottoms of many northern oceans. Unseen, and only recently discovered, the corals are vital to the health of the ocean ecosystem because they provide habitat for a large variety of species. High concentrations of fish and crustaceans live, spawn and feed around corals. Unlike the more familiar tropical corals, deep water corals are not dependent on the sun so they grow in the depths of the continental shelf at 200 metres (650 feet) or more. Cold water corals can take 100 years to grow one metre and can live for more than 2,000 years, making them perhaps the oldest living animals in the world.
Bottom corals not only attract fish but fishermen. Their trawl nets that drag along the bottom to catch fish have decimated coral in many places. One study estimated that 90 per cent of a reef discovered off eastern Canada was killed by bottom trawling. Others estimate that deep-sea corals may be disappearing faster than tropical corals.
Baffin Bay and Davis Strait are home to large reefs of cold water coral, documented from federal Department of Fisheries and Oceans groundfish surveys and from observer records measuring bycatch in bottom trawls. Without dedicated research on corals in the area, it is very difficult to estimate the range of this critical habitat or how quickly it is being destroyed by bottom trawling. In neighboring waters to the south, scientists and fishermen have found 27 species of coral. Based on observations made during underwater expeditions in Alaskaand British Columbia, cold water corals in Baffin Bay and Davis Strait are likely much more prevalent than is currently known.
Climate Change
Baffin Bay's deepest waters have been warming for the last 100 years, likely as a result of Atlantic waters moving north into the eastern part of the Bay. But colder and fresher Arctic waters also move south into the Bay along the shores of Baffin Island. One such pulse of freshwater in the early 1990s through Baffin Bay may have abruptly changed the populations and structure of the marine food web in the Northeast Atlantic as far south as North Carolina. Perhaps reflecting these complex and competing oceanographic influences, sea ice cover in Baffin Bay has been variable. The ice increased from 1952 to 2002 but appears to be decreasing since then.
Bottom trawler
© NOAA Photo Library, NOAA Central Library; Personnel of NOAA Ship MILLER FREEMAN 1985
Although the exact impact of climate change on Baffin Bay’s ecosystem is impossible to predict, already scientists tell us:
- Melting ice has allowed the first migration of Pacific plankton into Baffin Bay in 800,000 years.
- Increased killer whale use of northern waters likely means increased predation on Baffin Bay bowhead whales.
- Narwhal could suffer if there is a significant loss of sea ice in Baffin Bay because it is likely the Arctic marine mammal most sensitive to climate change.
- Warming water and increased fishing pressure could lead to a decrease in cold water Arctic species such as char and turbot and contribute to population swings of shrimp and cod.
Inuit
The Inuit have lived along the coast of Baffin Bay for thousands of years. Today, about 16,000 people live in the Baffin, or Qikiqtaaluk, region that includes islands to the north. The waters of Baffin Bay provide hunting platforms and transportation corridors for Inuit residents. The near-shore areas are also used for small community-based fisheries of Arctic char and turbot. Four local fish plants process some of the catch. However, the development of a near-shore fishery has been hampered by the lack of a permanent small boat harbour. The Government of Canada recently announced plans for a port facility in the Baffin community of Pangnirtung.
Commercial Fishing
Commercial Fishing
Baffin Bay and Davis Strait have the only large-scale commercial fisheries in Canada’s Arctic. Fishing vessels drag bottom trawls for turbot (also called Greenland halibut) and shrimp under quotas set by Canada’s participation in the North Atlantic Fisheries Organization, an international regional fishery management organization.
Turbot fishing in Davis Strait has a long history of exploitation by foreign and, more recently, Canadian trawlers. Baffin Bay’s northern fishery began in 1996 as a small test fishery. It expanded between 2001 and 2005 and again in 2009. The entire fish quota for the northern fishery goes to Baffin communities. In the south, Nunavut communities receive only part of the quota but have repeatedly petitioned for a greater catch share under the Nunavut Land Claims Agreement.
The federal government assigns the turbot and shrimp quota to Baffin Island communities and manages the fishery under a plan developed with the Nunavut Wildlife Management Board, a public governance body established by land claims. But without local ports, most of these communities have combined their allocations and leased them to the Baffin Fisheries Coalition that uses a Nunavut-owned trawler based in Iceland.
The federal government assigns the turbot and shrimp quota to Baffin Island communities and manages the fishery under a plan developed with the Nunavut Wildlife Management Board, a public governance body established by land claims. But without local ports, most of these communities have combined their allocations and leased them to the Baffin Fisheries Coalition that uses a Nunavut-owned trawler based in Iceland.
The ecological effects of the northern fishery’s expansion are difficult to measure or predict, especially in light of the dramatic shifts under way due to climate change. Bottom trawling can have a major impact on fish, corals and habitat. In the winter, narwhal feed on turbot below the ice at depths of up to 1,200 metres (400 feet) in places also targeted by bottom trawlers. In 2006, the Department of Fisheries and Oceans and the Nunavut Wildlife Management Board closed part of Baffin Bay to turbot fishing to protect narwhal winter habitat, a closure that was still in effect in 2009.
Turbot
© Smithsonian Institute
The 2006 turbot closure showed that the Nunavut Land Claims Agreement provides important tools for management of Baffin Bay through public governance bodies such as the Nunavut Wildlife Management Board and the Nunavut Marine Council. Together with the government of Nunavut and the Department of Fisheries and Oceans, these Inuit-led bodies provide a way to ensure Baffin’s marine wealth will be available for decades to come.
Many commercial fisheries around the world have been overfished, leaving habitats destroyed and communities bankrupt. Baffin Island has a chance to combine what Inuit have learned over thousands of years with lessons from past industrial fishing disasters.
Northern Solution
Oceans North Canada supports a community-led ecosystem study of Baffin Bay to develop a sustainable fishing plan that respects Inuit traditional practices, protects marine mammals, cold water corals and sensitive habitat, and provides jobs and fishing income over the long-term for Nunavut.
ENDNOTES:
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__ 2006. Fishery Management Plan Greenland Halibut NAFO Subarea 0 2006-2008 http://www.dfo-mpo.gc.ca/Library/333912.pdf
__ 2007. Development of a Closed Area in NAFO 0A to protect Narwhal Over-Wintering Grounds, including Deep-sea Corals.
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