By Paul Withers, CBC News, Feb 11, 2017
2-year project uses upward-facing echo sounders to observe marine life reaction to massive turbines
Researchers studying the environmental effects of tidal turbines in Nova Scotia’s Bay of Fundy are trying to answer one of the most important questions facing the technology: will fish and marine life in the Minas Passage steer clear of the turbines?
“The only way to figure out how they behave around it is to put one in the water,” said Haley Viehman, a researcher at Acadia University.
“It’s some of the most important information we can get.”
This month, Viehman began a two-year project to study fish behaviour in the Minas Passage. On Feb. 2, two upward-facing echo sounders mounted to a platform were lowered to the floor of the Minas Passage.
The echo sounders will track fish throughout the water column.
Maine research showed fish veered away
It will test a key claim by proponents: that where tidal turbines have been deployed elsewhere in the world, fish and marine mammals avoid them.
“This is why we are doing these studies at every site. To find out if this is the same at this site or not, compared to other sites,” said Viehman.
As a grad student, she studied a tidal turbine deployed in Maine. She said her research found fish veering away about 100 metres upstream.
In the Minas Passage, the first demonstration turbine — owned by Cape Sharp Tidal Ventures — is already generating enough electricity to power 500 homes.
The 1,000-tonne, five-storey turbine was deployed in November. More will be installed as companies and regulators examine the money-making potential and environmental impacts of tidal technology.
Researchers on this project, dubbed FAST 3, say the first goal is to ensure the sensors work in the churning currents, which can flow at five metres a second during peak tides. FAST stands for Fundy Advanced Sensor Technology.
Fishermen’s group opposes turbines
“I think the public needs to know we can’t take things off the shelf to expect them to work in the Minas Passage,” says Andrew Lowery, technical director of the Fundy Ocean Research Centre for Energy (FORCE), the agency managing the Crown test site.
“Something as simple as a camera. If we put that underwater in peak flood tide, it’s going to be like turning on your high beams in a snowstorm. It’s just a whitewash; you don’t see anything,” he says.
A fishermen’s group has gone to court to overturn the provincial government approval for the first turbine deployment, arguing there was not enough baseline scientific data. Justice Heather Robertson has reserved a decision on that.
Regulators dispute the fishermen’s concerns, but have ordered additional environmental effects monitoring for Cape Sharp Tidal Ventures turbine.
That program includes studies on marine mammals, fish, sea birds, lobsters and noise. The FAST 3 project is not part of that program.
“Social licence is important to us, satisfying our stakeholders is important to us,” says Lowery. “We are trying to bring our best game to the Minas Passage and satisfy everybody and answer some of these difficult questions that we do get. It is critical to make sure we can make this industry work.”
Source : CBC