Tuesday, 23 April 2019

A massive die-off of fish in Shoal Lake, in western Manitoba, has raised the possibility of a huge cleanup ahead.

by Larry Powell
Countless dead fish litter the shores. 
The magnitude of the die-off has emerged over the past few days, with spring breakup in full swing. The receding ice is revealing a shocking scene - thousands of fish carcasses piled up along the shorelines. Many more can be seen beneath the ice that hasn't melted yet. 
Gulls feast on the remains. (Eagles have also been seen doing the same.

The Mayor of the local government involved - Mervin Starzyk of the RM of Yellowhead  - tells PinP, he's waiting for more information from the province on what has happened. He says the Manitoba department of Sustainable Development (SD) has told him it may have been "winter kill." (That's usually a process involving a serious depletion of oxygen in the water.) 

The lake shares its name with a town
of some 700 people at its north end.
(Google map.)

Starzyk says any attempt to clean up will be both expensive and - without outside help - beyond the ability of the RM to carry out. 

Besides, he says, it's not really a local government responsibility anyway, since it's the province that's in charge of water resources. 

He says sewage from the Town of Shoal Lake's treatment plant drains into the lake. So phosphorous levels there are high and so is plant growth. These conditions can contribute to a process known as eutrophication, depleting oxygen and suffocating aquatic life. 

The Mayor says - if lack of oxygen is the problem - raising the lake level might help. But that would not be easy, since Oak River, which runs into the lake from the north, sometimes dries up.  Besides, controlling water levels is also the province's responsibility and not within his local government's jurisdiction. 

The Mayor adds, the RM is looking to purchase some marshland property east of town with lots of cattails, plants that are efficient at further cleansing treated sewage. If the deal can be completed, the town's sewage, rather than flowing into the lake, would be piped there, instead. But that plan, he notes, could prove expensive, as well - perhaps a million dollars. 

Starzyk says its depressing this has happened since many of the fish are scattered along the shore, right next to the golf course and clubhouse. It's a popular spot for locals and tourists alike, for both golfing and dining. It's feared the decomposing fish are almost certain to create an odour problem as the weather warms up. 
Some 2 years ago, hundreds of fish shown here,
struggle to get over a dam to spawn, just upstream
from Shoal lake, on the Oak River. All photos by PinP.
The lake is home to walleye, northern pike and perch. Another species, considered less desirable to anglers - the sucker - has also been abundant in the waterway for some time.