NWT RESEARCH DATABASE

Tags: water quality, biology, environmental monitoring, climate change, benthic invertebrates

Objective(s): To establish a baseline for benthic invertebrates’ community structure and composition in the transboundary reaches of the Slave and Hay Rivers.

Project Description: The objectives of this project is to establish a baseline for benthic invertebrates’ community structure and composition in the transboundary reaches of the Slave and Hay Rivers and to track their status and conditions over time to assess ecosystem health and provide an early warning of change or stress in the environment. The monitoring plan involves selecting and sampling several 500m long reaches of shoreline for benthic macroinvertebrates. The sampling method is a 3-minute travelling kick method, similar to the Canadian Aquatic Biomonitoring Network (CABIN) protocols developed by Environment Canada, where the sampler holds a sampling net downstream and kicks and disturbs the substrate for a period of 3 minutes moving upstream. The benthic invertebrates collected in the net are then preserved and sent to a lab for identification. Artificial substrate samplers will also be deployed in the river for a period of up to 6 weeks to collect benthic macroinvertebrates. The results from that passive sampling technique will be compared to the results obtained through the other sampling technique (modified CABIN method). Other supporting variables will be collected including water quality samples which will be analyzed for major ions, nutrients, metals and physical measures, algae, and information about the stream reach and habitat (e.g., velocity and depth of the water, description of the riparian vegetation). The project includes 2 phases. Phase 1 (Summer 2017) is a reconnaissance year where monitoring reaches and sub sites will be selected and the methods will be tested. The data from the initial sampling will be used to begin to characterize the benthic macroinvertebrate communities. A low level of sampling will be conducted at a small number of test stations (4-5 reaches). Artificial substrate samplers will also be deployed at some locations during Phase 1. Phase 2 (Summer 2018-2020) is a pilot monitoring phase that involves an intensive data collection to ensure the range of natural variability is captured. There will be between 6 and 10 reaches of each river (Slave and Hay) that will be sampled. Depending on the results from Phase 1, artificial substrate samplers may be deployed in Phase 2. The first year of the project the research team will explore the shoreline of the rivers to find appropriate sites and will test the sampling methods. ENR will hire a community member who knows each of the rivers to navigate and drive the boat (one person for the Slave River and one person for the Hay River). During the following 3 years, the research team would like to involve community members in the sampling part of the monitoring program, which will involve the collection of benthic macroinvertebrates through active sampling method, such as kick sampling, in addition to the deployment and retrieval of artificial substrate traps. The objective of this multi-year monitoring program is to test the methodology for monitoring benthic macroinvertebrates in Northwest Territories (NWT) large transboundary rivers and to collect baseline data for future assessment purposes. The NWT Water Stewardship Strategy Aboriginal Steering Committee, which includes representative from most Aboriginal governments, will be kept informed in all stages of the program. Updates will also occur in the Alberta-NWT Annual Report to the responsible Ministers which will be made public and posted on the NWT Water Stewardship Strategy website (http://www.nwtwaterstewardship.ca/). Public presentations of work under the transboundary agreement also will occur from time to time. The fieldwork for this study will be conducted from August 10, 2017 to October 15, 2017.