The Development of
Ecosystem Maintenance Indicators for the Liard River Basin
The Liard River, with a drainage area of 277,000 km2, rises in Yukon
and flows southward through British Columbia, where it meets the Fort
Nelson River at Fort Nelson. It then flows north to the Northwest
Territories to meet the Mackenzie River at Fort Simpson. The Liard
River is Canada's eleventh longest river with a length of 1100
kilometres and seventh largest by mean annual discharge of 2580
m3/sec. Within the Mackenzie River system, it has a greater effect on
Mackenzie River flow, temperature, sediment load and break-up than
any other tributary. The Liard River and its numerous tributaries
support a wide range of water uses including domestic water supply,
recreation, fish and aquatic life, agriculture and smallscale
industrial processes. Although unregulated and largely undeveloped,
the basin has considerable development potential for forestry and
hydroelectric operations. The natural environment of the basin,
especially the aquatic ecosystem, is used extensively by aboriginal
and non-aboriginal people.
This paper presents a preliminary evaluation of ecosystem maintenance
indicators for the Liard River that are responsive to changes in
streamflow. The hydrology of the basin is first described to show the
range of hydrologic conditions that affect the structure and
functioning of the aquatic ecosystem. Ecosystem goals and objectives
for the Liard River are then discussed followed by the evaluation of
key fish, mammals, riparian and aquatic plants and invertebrates,
birds and physical habitat features and their metrics that serve as
ecosystem indicators for maintaining a healthy and productive
ecosystem. Recommendations for further research are presented.
