Pauline Cove, on the southeast side of Herschel, is the only protective harbour between the Mackenzie River Delta in the Northwest Territories and Point Barrow, Alaska. The cove is deep enough to harbour modern, ocean-going vessels and has the added advantage of being protected from the prevailing northerly winds and drifting ice pack. Its role as a haven for ships made Herschel a key port during the last days of the oldtime whaling industry. The waters around Herschel Island are also a haven for fish and marine mammals. Generally, arctic waters are less productive than the warmer oceans to the south. Near Qikiqtaruk, however, the Mackenzie River empties into the Beaufort Sea and its warmer, nutrient-rich waters drift westward along the shore as far as Herschel Island. Invertebrates and other tiny sea creatures feed on these nutrients and are in turn eaten by larger fish, seals and whales. Arctic cod, pacific herring, and arctic flounder are all found in this area. Arctic char migrate out of the coastal rivers to spend part of their lives feeding in the ocean before returning to the rivers to spawn. The waters of the Mackenzie also bring wood from forested lands further south. The northern coast of the Yukon is barren of trees so this driftwood is the only local source of timber for building and burning. Pauline Cove has a number of historic buildings that date back to the turn of the century when American whalers would spend the winters between short whaling seasons.