NWT RESEARCH DATABASE

Tags: water quality, biology, dissolved oxygen

Objective(s): To directly measure temperature and dissolved oxygen concentrations in Airport Lake throughout the year, to find out if low oxygen levels are limiting the growth rate of Lake Trout population in this lake.

Project Description: The purpose of this study is to directly measure temperature and dissolved oxygen concentrations in Airport Lake throughout the year, and to find out if low oxygen levels are limiting the growth rate of lake trout population in this lake. Repeated sampling at the same locations on the lake during fall, winter, spring, and summer will show whether oxygen levels are adequate for optimal lake trout through the year, or if there are some periods of time when oxygen is depleted. The Principal Investigator (PI) will use a sonde to measure dissolved oxygen concentrations and water temperature at 1-meter intervals through the entire water column of Airport Lake, from 0.5 m below the surface all the way down to the bottom of the lake. A sonde is a small waterproof computer & sensor that measures water chemistry, that can be lowered into the lake on a cable off the side of a boat or while standing on ice. The research team will take two complete depth profiles at three different locations on Airport Lake, once per month for one full year. In summer the research team will operate the sonde from a small boat, and in winter will ski-doo onto the lake and drill a hole at each sampling location with an ice auger. Simple charts of oxygen concentration and temperature versus depth will be produced, and compared to lake trout habitat requirements that have been developed by the Ministry of Natural Resources in Ontario for use across Canada. The PI met with the Nihtat Renewable Resource Council (RRC) to discuss this project in early June. When the team meet again in early August their council members will identify the most important locations on Airport Lake for the team to sample. This project will coordinate the fall sampling period with his Environment and Natural Resources class at Aurora College so there can be an additional hands-on training opportunity during their Limnology section this fall. The field crew will be the Technician Trainee & Summer Student at the Gwich’in Renewable Resources Board (GRRB): youth residing in the Gwich’in Settlement Area who are gaining experience and training in biology and environmental science. The principal investigator will report progress and project results directly to the Nihtat RRC at their monthly council meetings. The principal investigator will also give oral presentations on the project’s results to the GRRB at their Board meetings in September 2018. Board meetings are open to the public, and representatives from all four communities in the Gwich’in Settlement Area will be attending the Board meeting. After the year of sampling has ended, the principal investigator will write a brief written report summarizing the findings and distribute it to the Nihtat RRC and GRRB. The fieldwork for this study will be conducted from September 18, 2017 to December 31, 2017.