Island watershed group using ‘light’ electric shocks to monitor fish stocks
An Island watershed group is using a technique called electrofishing to record fish stocks.
The Souris and Area Branch of the P.E.I. Wildlife Federation has used the method for a few years to help it better understand fish health in its surrounding rivers and streams.
Electrofishing uses mild electrical currents — between an anode and a submerged cathode — from an electrofishing device in the water to slightly stun fish to safely capture them.
Keila Miller, a project manager with the watershed group, said the process does not harm the fish.
“Your fish will kind of float to the top, you’ll net them and you’ll put them into the bucket and by the time you’ve put them into the bucket, within 10 to 15 seconds they’ve already recovered,” she said.
“It gives them a light shock. The mortality rate is very, very low.”
Healthy fish populations
Once the fish — such as Atlantic salmon and brook trout — are captured, the non-profit records the species and measurements, and then releases them.
Miller said they can only conduct this kind of testing during the spring and fall because warmer water can negatively affect how the fish react to the electrical current.
“A lot of places — the fish populations are decreasing.” – Frances Braceland, project manager.
The group was able to acquire the machine — which costs around $13,000 — through funding it secured from a federal program.
Project manager Frances Braceland said electrofishing provides an opportunity to see how the fish stocks are doing.
“It’s great to be able to go through and pick them up and look and see that you do have a healthy population of fish in your streams. It’s kind of the reward you get for all the work you’ve put in all year round.”
The fish density surveys are part of a research project in Hay River that the group has been conducting for the past few weeks.
It’s funded by the Atlantic Salmon Conservation Foundation and the World Wildlife Federation — the goal being to get a better picture about fish health on P.E.I.
“If the numbers are down for whatever reason, we have to look at our restoration methods and think about what’s missing or what has happened that has made the numbers go down,” said Miller.
Report published later this year
Braceland said the fact that the watershed’s fish populations have remained stable is a clear sign the work it’s been doing is making a difference.
“A lot of places — the fish populations are decreasing,” Braceland said. “In our area, we’re getting fairly stable numbers so we know that, one of the main reasons we think that is anyway, is the fact that we have extensive restoration work.”
The group will finish its survey work on Friday. Once the information is analyzed, the group will produce a public report expected in December.