Randall Island is part of the Dundas Archipelago, a group of islands located in Hecate Strait, on the west side of Chatham Sound between Brown and Caamaño Passages, about 74 miles (119 km) southeast of Ketchikan and 22 miles (35 km) west-northwest of Prince Rupert, British Columbia. The Dundas Archipelago was named in 1792 by Captain George Vancouver for Henry Dundas, who was the British Treasurer of the Navy from 1783–1801. Dundas was granted the title of Viscount Melville in 1802 and also named Baron Dunira. The Dundas Archipelago was originally perceived by Vancouver to be one island which he named Dundas Island, but are now known to consist of several smaller islands including Baron Island, Dunira Island, Melville Island, and Randall Island. Chatham Sound is on the border between British Columbia and Alaska. It is part of the Inside Passage and extends from Portland Inlet in the north to Porcher Island in the south. It may have been named in 1788 by British Captain Charles Duncan after John Pitt, 2nd Earl of Chatham, who was First Lord of the Admiralty at that time. The sound has an area of about 383,999 acres (155,399 ha) and is connected to the open waters of Hecate Strait and Dixon Entrance via several channels including Main, Brown, Hudson Bay, and Edye Passages. Along its southern end, the sound provides access to inland passages such as the Marcus and Arthur Passages, and the Grenville Channel beyond that. The two major rivers that drain into the sound are the Nass River via Portland Inlet and the Skeena River via the Inverness and Marcus Passages. The salinity of the sound is considerably lower than the adjacent ocean because of the large inflow of freshwater. The islands of the Dundas Archipelago are part of the Alexander terrane, a tectonic fragment that underlies much of Southeast Alaska, Yukon, and British Columbia. The Alexander terrane was further subdivided into the Craig subterrane to the south and Admiralty subterrane to the north based on apparent differences in their geologic records. The Dundas Archipelago belongs to the Craig subterrane which consists of Late Triassic limestone, basalt–andesite, and rhyolite which overlie limestone from the Late Paleozoic.

The Cordilleran ice sheet during the Last Glacial Maximum, about 18,000 years ago, advanced and overrode the Dundas Archipelago. Glacial ice flowed west toward the coast from the interior through major outlets including the river valleys of the Skeena, Nass, and Stikine. The coast was isostatically depressed by the mass of continental ice sheets and when the ice began retreating, post-glacial rebound contributed to keeping shorelines above the rising sea level. However, coastal archaeological sites dating to the late Pleistocene and early Holocene are rare due to the rapidly changing relative sea level. There are currently no archaeological sites in the Americas that are widely accepted as dating to the period before the Last Glacial Maximum. The effects of late-glacial sea-level change continued well into the early part of the Holocene period with continued isostatic adjustment and eustatic sea-level change. The Dundas Archipelago is within Coast Tsimshian territory and the archaeological evidence suggests that humans appeared along the present shoreline near Prince Rupert about 5,000 years ago. Tsimshian translates to ‘Inside the Skeena River’ and at one time the Tsimshian lived on the upper reaches of the Skeena River. According to Tsimshian oral history, after a series of disasters befell the people, a chief led a migration away from the interior to the coast and established the village of Kitkatla. Over time, these coastal bands developed a new dialect of their ancestral language and came to regard themselves as a distinct population. When the Hudson’s Bay Company moved their fort from the Nass River to present-day Port Simpson in 1834, about 15 miles (24 km) northwest of the Dundas Archipelago, most of the coastal Tsimshian villages moved to what is now called Lax Kw’alaams. The islands of the Dundas Archipelago are now part of the Lax Kwaxl/Dundas and Melville Islands Conservancy. In 2006, the conservancy designation was first introduced as a protected area in British Columbia. The designation is unique in that the legislation explicitly recognizes the importance of these protected areas for social, ceremonial, and cultural uses, while also allowing First Nations to pursue opportunities for low-impact, sustainable economic development. The islands have a rich cultural and social significance to the Tsimshian people and contain numerous seasonal camps with historical importance that are still used for fishing and gathering subsistence foods.

The diurnal tidal fluctuation in the Dundas Archipelago is 23 feet (7 m) from maximum low tide to maximum high tide. The combination of the crenulated shoreline morphology, large tidal fluctuation, flat topography, and strong currents, has resulted in a large and highly productive intertidal zone. The islands have extensive peat bogs and flat poorly drained areas are widespread characterized by sphagnum, lodgepole pine,  and yellow cedar. Climax vegetation is dominated by western red cedar, red alder, and western hemlock in better-drained areas. The terrestrial fauna is very limited given the small size of the isolated islands, but the grey wolf was introduced sometime in the 1980s and now inhabits all the islands of the archipelago. The grey wolves of coastal British Columbia are a remnant group of a much larger population that once inhabited most of North America. Coastal wolves are found west of the Coast Mountains in remote temperate rainforests. This range includes the many islands and archipelagos on the coast, as they are very capable swimmers. The presence of deer in wolf diet is more common close to the mainland compared with isolated islands such as the Dundas Archipelago which is 7.5 miles (12 km) from the mainland and where they must consume higher quantities of smaller prey. As islands increase in insularity, deer are most often replaced by small mammals, birds, salmon, and seals. Their reliance on salmon is highest during the spawning season in the fall. Coastal wolves are part of an ecosystem that has a strong land-sea connection where nutrients that are taken up by salmon at sea are brought to shore during the spawning migration. Studies of stable isotopes have shown that when salmon are caught and consumed by predators such as coastal wolves, the nutrients are passed on and taken up by a range of terrestrial organisms including scavenging insects, small mammals, and even plants. Read more here and here. Explore more of Randall Island and the Dundas Archipelago here: