Effects of environment on fish species distributions in the Mackenzie River drainage basin of northeastern British Columbia, Canada

Abstract

Abstract – The northeast of British Columbia is subject to rapid development by the oil and gas sector. In addition, forestry, tourism and agriculture are all affecting the environment. Knowledge of fish distributions in the region is limited, yet such information is important if environmental impact assessments are to be taken for future developments. Data from fish inventories for 261 stream reaches from the Milligan Creek, Halfway‐Graham River, Fort Nelson River and Gataga River were analyzed using canonical correspondence analysis, with fish presence being related to a suite of environmental variables. The most important environmental variables affecting the species of fish present in a reach were water temperature, boulder cover and reach width. As water temperature and, to a lesser extent, reach width, can be affected by industrial development in a number of ways, there is a likelihood of environmental impacts associated with the current spate of development in the region.