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The Beaver Brown Waters of Rupert Bay 

Published 4 min read
By Thirstier News

The Cree word pahtaaunaakun seems particularly apt for describing the distinctive brown hues of the waters that drain into Hannah Bay and Rupert Bay in Canada. Meaning the “color of singed beaver” in Southern East Cree, the word evokes the rich brown of the humic-substance-stained waters that were flowing into the two bays in late September 2026, as well as the role that beavers have long played in the mythology and history of the region.

As the rivers and streams that flow into the two bays—the southernmost extensions of James Bay—wind through the boreal forests and boggy wetlands of northern Quebec and Ontario, they often carry water stained brown by colored dissolved organic matter (CDOM), which absorbs light in the blue and ultraviolet parts of the electromagnetic spectrum and causes water to appear brown. CDOM, including organic substances derived from tannins and lignins, leaches from decaying leaves, roots, bark, and soils into streams and rivers. Similar substances are what stain tea water brown.

When the OLI (Operational Land Imager) on Landsat 9 captured this image on September 27, 2026, the Moose, Nottaway, and Harricanaw rivers were carrying tea-colored water across the broad mudflats of Hannah and Rupert bays and mingling with the darker blue waters of James Bay.

The mudflats, the light brown areas along the shore, are a product of the shallow, sloping bathymetry in the southernmost part of James Bay. Postglacial rebound is slowly lifting the entire landscape, and rivers continually deposit fine mud particles and other sediments that build up the flats. The comings and goings of tides and river currents often stir up the mud, producing the lighter brown plumes of suspended sediment that mix with the incoming river water.

Differences in moisture levels and vegetation patterns likely contribute to the green dendritic, veinlike patterns visible onshore. Denser, more forested growth along stream channels appears dark green, while the poorly drained landscapes in the surrounding peat bogs have less extensive tree cover and appear lighter green.

Beavers have long played a role in the history and mythology of the lake-dotted landscapes in this part of Canada. The Cree people, who have lived in the region for thousands of years, have traditionally hunted beaver for both meat and pelts. European traders arrived in Rupert Bay as early as the 1660s to pursue the animals as well, leading to the establishment of several trading posts along the bay’s shores and the founding of the Hudson’s Bay Company to cultivate the fur trade, especially in beaver pelts.

Beavers also feature prominently in the area’s Cree mythology and environmental history in other ways. For instance, one Cree myth about this area, recorded by the anthropologist Alanson Skinner, tells of a giant pursuing an enormous mythical beaver down the Nottaway River until the beaver escaped into Rupert Bay. According to the myth, the giant then picked up a huge rock and hurled it at the fleeing animal, missing the beaver but creating Stag Rock, the distinctive island found in the river’s mouth today.

In an early example of a managed beaver preserve in Canada, the Hudson’s Bay Company worked with local Cree people in the 1830s and again a century later to set up Charlton Island as a place to raise beavers for later trapping. After predators had been removed and several breeding pairs delivered to the island, its beaver population ballooned, according to historical accounts.

NASA Earth Observatory images by Lauren Dauphin, using Landsat data from the U.S. Geological Survey. Story by Adam Voiland.

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Source: NASA