Offshore renewable energy installations are lauded for their potential to combat climate change but they can also inflict a heavy toll on marine life and their ecosystems, according to a study released Tuesday.
The study, published in the journal Trends in Ecology and Evolution, reports that as more countries and companies around the world embrace greener, marine-based technologies that help communities fulfill their energy needs, it is becoming evident that such technology can wreak havoc on underwater marine life if implemented irresponsibly.
Researchers suggest that if marine renewable energy devices (MREDs) – such as wave energy converters and wind turbines – are placed in marine environments without consideration of environmental consequences, marine life could be severely damaged.
That stands in stark contrast to the environmentally friendly mindset that drives such devices in the first place.
The study insists that these energy devices can greatly advance climate goals but cautions that greater thought must be given to when, where and how they are implemented.
“MREDs and other renewable options are integral to any nation’s climate strategy because they are undoubtedly less climate-forcing than burning fossil fuels. However, as nations tackle the problem of climate change, they must not ignore the potential for damaging wildlife populations and ecosystems in the process: It matters little to a species if the habitat loss driving them to extinction is caused by climate-related changes or MRED installations,” the study states.
Researchers say that one of the most obvious threats these devices pose to marine life are their propellers. As more large propellers and blades whirl underneath the water in an effort to create energy, undersea creatures are placed at an increased risk of being struck and harmed by the machines.
Scientists note that similar conversations are being had about wind turbines on land and their influence on bird populations and their migration patterns.
Andrew Wright, first author on the study and an ocean and ecosystem scientist with the Natural Sciences and Engineering Research Council of Canada, reports that installation noise can also be a potential drawback to renewable energy devices.
“Installing renewable energy sources in the ocean is a loud operation. I would compare building MREDs to living next to a construction site. Think about what it’d be like to live next to all those jackhammers and power drills,” Wright said in a statement. “I don’t think a lot of people appreciate that when it’s offshore, it may be silent for humans, but if they stick their head under water where the animals live, it’s much, much louder.”
With so many marine animals relying on sound-based echolocation, a navigational ability used by many underwater creatures while they migrate and collect food, the loud and continual sounds coming from device installation activity could significantly disrupt marine life.
These problems can persist, the study says, even after installation is complete. Researchers say that some devices emit a low-frequency sound that, while unperceivable to some, routinely invade animals that can pick up that frequency, such as certain species of endangered whales.
Researchers warn that these sounds can be so pervasive they could ultimately obscure other sounds marine life needs to be able to pick up on to survive, such as the sounds of nearby predators and prey.
Wright says that the goal of the study is not to create feelings of hostility towards these devices or convince people to turn against them. Rather, Wright hopes, the study will remind people that regardless of the intentions, these kinds of device implementations need to be done carefully and with a full consideration of all potential consequences.
“We don’t want to slow anything down. We just want everyone to be a bit more strategic in their efforts. We all agree that climate change is a big problem that needs solutions, but it’s important to make sure that the solutions we implement don’t have too much collateral damage along the way,” Wright said.