September 8, 2022 · 0 Comments
As part of their on-going monitoring of local waterways and restoration projects, the Nottawasaga Valley Conservation Authority conducted a survey of fish species along a section of the Nottawasaga River in Adjala-Tosorontio on Wednesday, August 31.
NVCA staff and volunteers spent the morning at a section of the river that runs through farm property on the Adjala 20 Side Road.
They moved their research to another property on Hockley Road in the afternoon.
NVCA previously did a restoration of the river bank in the area and they were back to see how it affected fish species in the river.
Most of the fish species in the river are cold water fish meaning they need cooler temperatures to survive.
The group collect fish using a technique called “electro fishing.”
As most of the fish are small and hidden under logs and other obstructions, collecting them for study is difficult.
With electro fishing, an electric current is sent into the water via hand held wands that are power by a generator. The electric current causes the fish to swim out from their hiding spots and they are easily captured in a net. After identifying and counting the fish, they are released back into the river.
The group discovered lake trout, Chinook salmon, brook trout, rainbow trout, bass, brown trout, river lamprey and several other species.
“The work we’re going to stabilized the banks and improve habitat and control sediment also helps lake sturgeon downstream,” explained Fred Dobbs, a fisheries biologist and Manger of Stewardship Services for the NVCA. “What we’re doing today is working on year five of what may be the biggest trout stream initiative in all of southern Ontario right now, called the Nottawasaga River Restoration Program. We’ve actually flattened out the banks and put a whole series of invasive tree root wads that not only stabilize the structure, it provides a place for fish cover and provides attachment habitats for bugs that filter feed and clean the water.
“We’ve just finished 900 metres of restoration on this property. This area was sampled in 2018 and 19, before we did the restoration work. The restoration was done by volunteers but also followed up with heavy machinery. Now that the bank stabilization and habitat installation has been completed, we’re back to see if the abundance of fish and percentage of sensitive fish like trout and salmon has improved since before we did the work.”
The group moved to the Hockley location in the afternoon.
“We consider the village of Hockley to be in a high-quality reference condition, including water quality,” Mr. Dobbs explained. “By restoring downstream here, we are trying to bring the river down here as close as we can to that high standard coming out of the escarpment. We’ll be sampling there later today to see how close the fish community here is starting to get to that high quality. The work up at Hockley is a controlled reference reach. It sets the bar for what we are trying to achieve here.”
The volunteers worked in a close group, wading in the river to capture the fish for study.
By Brian Lockhart