Temperature loggers deployed in rivers
Salmon association deploys temperature loggers in rivers
MARGAREE — A program taking place in Cape Breton rivers hopes to gather enough data to help the future of habitat restoration for freshwater salmon.
The temperature monitoring initiative is part of a Gulf Priority Rivers project that is being funded by the Canada Nature Fund for Aquatic Species at Risk through the Nova Scotia Salmon Association.
The temperature loggers, which began recording data on June 15 of this year, are small golf ball-sized devices that have been submerged in watersheds and rivers at certain sites and have been set to record the water temperature every 15 minutes.
“We're doing them in priority rivers,” said Amy Weston, manager of habitat programs at the Nova Scotia Salmon Association. “We have four priority rivers in the gulf side, two in Cape Breton, two in Antigonish County and other parts of the province. So it's actually a pretty big data set that we're collecting.”
The 30 temperature monitors in Cape Breton are installed along the Margaree River, the Mabou River, the South River and the West River.
“We try to have them out of site and also in the shade and as deep into the pool as possible, so that they stay submerged throughout the whole recording season,” said Weston, who noted they have small signs near the monitors so that people know to leave them alone.
“Temperature is a really driving factor for salmon and for all cold-water species, so it's of interest to us always,” said Weston.
Margaree Salmon Association president Bill Haley said one of the purposes of the project is to track the potential impact of climate change on the rivers, as well as to identify areas of refuge for cold-water fish species during summer months with intense heat.
“These species, they need cold water to survive,” said Haley. “If the water temperature gets up to 25 or 30 (Celsius) — especially if it approaches the high 20s — there's not enough oxygen in warm water to keep them alive so they'll suffocate.”
The partnership project between Margaree Salmon Association and the Nova Scotia Salmon Association will begin pulling data from the temperature loggers in September, and use it to enhance areas.
“We can do habitat restoration, whether it's deflectors, whether it's digger logs, whether it's riparian planting,” said Haley.
He said the temperature on the Margaree River is tracked remotely every day. If temperatures of 20 C or more are recorded for 48 consecutive hours, a meeting is convened with the partners that are involved with the program, including the federal Department of Fisheries and Oceans and the Unama'ki Institute of Natural Resources.
Haley said in that situation, they would “probably” decide to close the river to recreational angling.
“I say probably because we will consider the weather, whether it's going to be extremely warm temperatures coming or cold temperatures coming, if there is rain in the immediate forecast. We look at a variety of things,” he said.
The data from the temperature monitoring will also be another way to assess the impact of the Margaree Salmon Association's habitat restoration work.
“It'll allow us to see, Did that work help enhance, or lower, the temperature of the river during particular times of the year,” said Haley. “But in addition to that, it will help us identify the locations where new structure and new restoration work is needed.”
The project has been funded for four years so far, but Haley said it will be running “indefinitely.”
“As far as we're concerned, we'll find the funding to keep this watershed healthy,” he said.