Scientists look for endangered eels
Task precedes pier work in Port
Research scientists are combing the waters of Port Dalhousie in the dead of night searching for an endangered species of eel in anticipation of construction work on the piers.
The team from Fisheries and Oceans Canada were on the waters in the wee hours of the morning Tuesday to determine if American eels are living in the piers and old break walls.
“Initially our survey is just going to try and determine if they’re present and if they are, we’re going to try and re-locate them,” said Tom Pratt, a research scientist with Great Lakes laboratory for fisheries and aquatics sciences.
Pratt said the team didn’t find any of the nocturnal eels in five hours overnight Monday to Tuesday but are expecting to be out each night until Thursday, weather permitting.
The American eel is listed as endangered under the Ontario’s Endangered Species Act and threatened under the Federal Species at Risk Act.
“It’s a pretty rare fish and it’s extremely unique in Canada,” Pratt said. “It’s the only fish that we have in Ontario that spawns in the ocean and then completes the rest of its life cycle here in freshwater.”
A fish with a long, snake-like body, the American eel spawns south of Bermuda in the Sargasso Sea and migrates along the east coast of North America. It lives in fresh water until it’s 10 to 25 years old and then returns to the Sargasso Sea to spawn.
Pratt said researchers don’t know what they’ll find in Port Dalhousie, but historically the eel would live in piers and break walls in the area.
“They certainly love the kind of habitat that’s available there,” he said, explaining they like big rocky outcrops.
The idea is to remove the fish to safety because of the impending piers reconstruction.
The researchers are electrofishing in and around the harbour — a technique used to determine the presence and abundance of fish populations. They use a special boat with electrodes that puts a very low level of electricity in the water. Fish are temporarily stunned for a few seconds so the team can make observations and net eels if there are any. There is no permanent harm done to the fish.
Pratt explained if they manage to net eels, they’ll put some in a large tank, tag them and release them near Jones Beach, about five kilometres away. The tags will be picked up by audio receivers.
The scientists will come back to Port Dalhousie in two months and if the tagged eels have not returned, they’ll know they can start removing and re-homing all eels as soon as they wish.
If the tagged eels have come back, the scientists will know that re-hom-
ing needs to be done closer to the start date for refurbishing the piers.
“There’s no point in removing them if we know they’re going to sneak back,” Pratt said. “But if they stay away, then any kind of removals can be done starting right away and there isn’t quite as much urgency at that point.”