Aquatic habitats in arctic and sub-arctic regions are particularly sensitive to the effects of global climate change and human activities. Aquatic insects are ideal for monitoring, but information about their distributions and ecology in the north is limited. We sampled benthos from 46 tributary streams of the Mackenzie River in the Northwest Territories, Canada, during the period of 2005 to 2007, and also analyzed monitoring data from tributaries of the Athabasca River in northern Alberta. Although habitat characteristics, such as substrate, water chemistry and winter ice formation, are important in structuring the benthic invertebrate community, large-scale latitudinal gradients are also present in the system which suggest an increasingly cold-adapted fauna. An overall decrease in diversity occurs with increasing latitude, and changes in species composition are apparent. The Chironomidae increasingly dominate the stream benthic fauna in the north, and certain species of other groups of insects (Baetidae, Brachycentridae and Nemouridae, among others) become abundant only in the far north of the study area. This presentation will provide details of these latitudinal and other factors that affect the benthic invertebrate community, and discuss the implications of these gradients for monitoring climate change.