COVID-19 might be terrifying the rest of the world, but the whales sure are probably enjoying it. Declines in the economy due to the coronavirus have slowed exports and imports by around 20 percent and this has caused a dramatic decrease in the ocean noise.
Oceanographer David Barclay of Canada’s Dalhousie University and his team have been analyzing ocean sound signals from seabed observatories run by Ocean Networks Canada near the port of Vancouver. Their observations of sound power in the 100 Hz range from two sites have revealed a decrease in noise level of up to five decibels.
“There has been a consistent drop in noise since January 1, which has amounted to a change of four or five decibels in the period up to April 1,” Barclay told The Guardian. “Generally, we know underwater noise at this frequency has effects on marine mammals.”
The two research locations include a deep-ocean site approximately 60 kilometers (37 miles) from the Vancouver port in 3,000 meters (9,842 feet) of water and a more shallow inland site. The deepwater location recorded a drop in weekly noise of 1.5 decibels.
A study of baleen whales after the 9/11 attacks in 2001 showed that the reduction in ship and air traffic was associated with a reduction in chronic stress in marine mammals.
“We are facing a moment of truth,” Michelle Fournet, a marine acoustician at Cornell University, who studies humpback whales in southeast Alaska, told The Guardian. “We have an opportunity to listen – and that opportunity to listen will not appear again in our lifetime. “
“We have a generation of humpbacks that have never known a quiet ocean,” said Fournet.
The drop in tourism has also been a source of the decline of ocean traffic, another added benefit for cetaceans. Late April generally marks the beginning of the cruise ship season in southeast Alaska with boats docking in Vancouver before heading to the 49th state.
“What we know about whales in southeast Alaska is that when it gets noisy they call less, and when boats go by they call less,” said Fournet. “I expect what we might see is an opportunity for whales to have more conversation and to have more complex conversation.”
“The clearest benefit of the reduction in vessel traffic is to humpback mothers and nursing calves, who tend to be somewhat reclusive,” Marc Lammers, research coordinator for the Hawaiian Islands Humpback Whale National Marine Sanctuary, told Hawaii’s Star-Advertiser. “Not having humans either trying to view them or, in some cases, interact with them will be a huge benefit for the mother, whose priority is to protect and nurse her calf so it can be strong enough to make the trip to Alaska. It allows her to conserve her energy and transfer that energy to her calf in peace, without having to respond to stand-up paddlers and five or six boats approaching at a time.”
