The novel coronavirus pandemic is having a profound impact on marine wildlife — and it’s both good and bad.
A new report released by Ocean Wise, a not-for-profit organization aimed at supporting the world’s oceans, found a global slowdown of marine traffic has led to several unintended consequences for marine mammals.
In COVID-19: A Story of Marine Mammals, which was co-authored by an all-woman team, researchers broke down the effects of the COVID-19 pandemic into three categories: marine vessel traffic; plastic pollution; and changes in the way data is collected.
Marine traffic is down
With the development and expansion of international trade, shipping and tourism, there are more vessels like freight tankers and ships on the water than ever. Boats are loud, and that noise comes at a price.
The report noted that cetaceans, a group of marine mammals that includes beluga whales, dolphins and porpoises, rely on sound for many aspects of their lives — to communicate and stay in touch with one another, to detect predators, and to hunt for food.
When underwater noise gets too loud, all these sensory activities become impaired, the report said, driving cetaceans to make dramatic changes to their migration paths, bypass feeding and nursing sites, “use more energy searching for food, and produce higher levels of the stress hormone cortisol.”
“Think of noise as a bit of an acoustic smog,” said Valeria Vergara, a research scientist with Ocean Wise who contributed to the report, in an interview.
“If we humans had to navigate in a visual smog, we would find that difficult. We would find it difficult to connect with each other, to see each other, to find each other. Sound to whales is like vision to us.”
Since COVID-19 was officially declared a pandemic in March, Vergara said her team found significant reductions in low-frequency noise produced by ships “pretty much immediately” — mainly because there were fewer out on the ocean.
“Locally, the number of B.C. Ferries sailings were reduced by about 80 per cent from the start of April,” the report read.
Coming out of the pandemic, Vergara said it is inevitable that traffic will pick up. But reducing the speed at which boats travel, or buying locally in order to put less demand on shipping companies, can help cut down on the amount of noise produced by marine vessels.
Plastic pollution on the rise
But while noise pollution is down, the report found pollution was up.
Once plastic gets into the ocean, it can be hard to fish it back out. Instead of biodegrading, the report noted that most plastics simply break into tinier fragments until they become known as micro-plastics, which are less than five millimetres in size.
“Plastics — both micro-plastics and larger fragments — are often mistaken for food by marine animals, which can result in malnutrition, starvation or even death,” the report states.
Researchers found that many restaurants and shops reverted back to single-use and disposable plastics to help minimize the spread of COVID-19 rather than reusable bags, and that an increase in personal protective equipment contributed to the “plastic waste stream.”
“Lost, discarded and abandoned fishing lines, nets or rope, also known as ghost fishing gear — most of which is made from plastic — are often responsible for marine entanglements,” the report states.
At the current pace, the researchers estimated up to 13 million metric tons would enter the world’s oceans per year.
Dr. Rashid Sumaila, a professor and director of the Fisheries Economics Research Unit at the University of British Columbia’s Institute for the Oceans and Fisheries, said that if this isn’t reduced, the results could be “wild.”
“There’s this fear we have if we don’t do the right things, we could end up with more plastic in the ocean than fish in terms of weight, and that is very scary,” he said.
Sumaila said solving that problem is a multi-solution approach that involves consumers reducing the amount of waste they discard, policy-level action from all levels of government, and scientific research into bacteria that can be used to replace plastic.
Amber Dearden, who co-authored the report, told Global News the report’s findings were far from surprising.
“We all know that during COVID-19, plastic use has gone up,” she said.
While expected, Dearden said she had concerns about the effect it would have on animals, more of which were at risk of getting entangled in plastic.
Due to pandemic restrictions, she said staff at the Ocean Wise Marine Mammal Rescue Centre (MMRC) have been unable to rescue as many entangled marine mammals — which could become problematic as more and more plastic is found in the ocean.
According to the report, the MMRC received nine calls for entangled sea lions between March and mid-May. Of those, researchers said they were unable to respond to six of them due to staff reductions and centre closures, including one call from a federal park that was closed at the time.
Fewer sightings, skewed data
According to the report, the number of whale, dolphin and porpoise sightings reported from land was 66 per cent higher than it was at around the same time last year, while the number of sightings reported from the sea — such as observers in boats and designated whale-watcher boats — decreased by 64 per cent.
The British Columbia Cetacean Sightings Network (BCCSN), which Rowley described as a “small army of volunteer observers,” report sightings from anywhere across the coast.
Those sightings are sent as real-time alerts to captains of larger commercial vessels via the Whale Report Alert System to help prevent ships from accidental whale strikes or contributing too much underwater noise.
“The idea is that by alerting ship captains to the presence of whales that we know are in that vicinity or in their path, they can slow down, be more vigilant, post an extra watch or even change course around the whale,” said Rowley.
She said her team found a 46 per cent drop in marine mammal sightings around B.C. since the pandemic began.
Amy Rowley, a report contributor and research assistant with the BCCSN, said the drop in sightings could be easily attributed to public health regulations that shut down tourism and ferries, which account for most sighting reports used by tracking systems.
To make up for the lack of data in some areas, Rowley said she anticipated a targeted outreach into areas where land observations were high, which she hoped would encourage more cetacean sightings and fill in the blanks where there is missing information.
“The more sightings we receive, the more protected the whales are,” she said.