Classification of Stream Types in Beaufort Sea Drainages between Prudhoe Bay, Alaska, and the Mackenzie Delta, N. W. T., Canada

Abstract

Arctic streams in Beaufort Sea drainages from Prudhoe Bay, Alaska, to the Mackenzie River delta are described and classified. Mountain Streams originate in the Arctic Mountain Province and are the largest streams in the study area. These are cold waters (usually less than 10°C) which flow about five months of the year. Arctic char is the common fish species in these streams, and the density of benthic invertebrates is typically low (100 organisms/m²). Spring Streams are small spring-fed tributaries of Mountain Streams. Most are fresh water with temperatures of 3 to 7°C although thermal and mineral springs do occur. The springs are inhabited by Arctic char and high densities of benthic invertebrates (10.000 organisms/m²). Tundra Streams originate in the Foothills and Coastal Plain Provinces and flow for 3.5 to 4.5 months of the year. Their waters are stained brown and have a lower pH, conductance and lower concentrations of calcium than found in Mountain or Spring Streams. Summer water temperatures may exceed 16°C. These streams are used as spawning and rearing areas by grayling. Densities of benthic invertebrates are between the other stream types.