The VENUS ocean observatory network is clarifying the degree to which waters around Vancouver Island are infused with the shipping noise. The data is reinforcing concerns that local orcas and other sea creatures are likely to experience several negative impacts, including chronic stress, the need to use more energy to talk louder, and perhaps interference in foraging. A good article in the Vancouver Island-based Times-Courier (excerpted below) details the findings.
“The noise is virtually continuous during daylight hours and quietens a little bit overnight,” Richard Dewey, associate research director on the University of Victoria’s VENUS (Victoria Experimental Network Under the Sea) project, said. “In addition to the annoyance of the constant din, [the whales] are likely to have to shout over the engine sounds and listen through the racket to pick out and identify the messages.” Tricky tasks, such as the use of broadband clicks to echo-locate fish — the sole diet for resident killer whales — is likely to be extremely difficult when boats and ships are nearby, Dewey said.
It was expected the Strait of Georgia would be noisy as it is one of the busiest shipping lanes in the world, but among recent changes is the increase in massive container freighters. “They travel at twice the speed that vessels used to travel at, they use four times as much energy and make four times as much noise in the ocean,” Dewey said.
One of the — as yet unanswered — research questions is whether the whales can survive increasing noise at the same time as they are coping with shrinking salmon runs and climate change. “Whether the whales and dolphins can adapt is an open question,” Dewey said.
Learn more at the VENUS website.