In hot water? Study says warming may reduce sea life by 17%

Every degree Celsius that the world’s oceans warm, the total mass of sea animals is projected to drop by 5 per cent

The world’s oceans will likely lose about one-sixth of their fish and other marine life by the end of the century if climate change continues on its current path, a new study says.

Every degree Celsius that the world’s oceans warm, the total mass of sea animals is projected to drop by 5%, according to a comprehensive computer-based study by an international team of marine biologists. And that does not include effects of fishing.

If the world’s greenhouse gas emissions stay at the present rate, that means a 17% loss of biomass — the total weight of all the marine animal life — by the year 2100, according to Tuesday’s study in the Proceedings of the National Academy of Sciences. But if the world reduces carbon pollution, losses can be limited to only about 5%, the study said.

“We will see a large decrease in the biomass of the oceans,” if the world doesn’t slow climate change, said study co-author William Cheung, a marine ecologist at the University of British Columbia. “There are already changes that have been observed.”

While warmer water is the biggest factor, climate change also produces oceans that are more acidic and have less oxygen, which also harms sea life, Cheung said.

Much of the world relies on the oceans for food or livelihood, scientists say.

READ MORE: Canada to ban single-use plastics in 2021

“The potential ramifications of these predicted losses are huge, not just for ocean biodiversity, but because people around the world rely on ocean resources,” said University of Victoria biology professor Julia Baum, who wasn’t part of the study but says it makes sense. “Climate change has the potential to cause serious new conflicts over ocean resource use and global food security, particularly as human population continues to grow this century.”

The biggest animals in the oceans are going to be hit hardest, said study co-author Derek Tittensor, a marine ecologist at the United Nations World Conservation Monitoring Center in England.

“The good news here is that the main building blocks of marine life, plankton and bacteria may decline less heavily, the bad news is that those marine animals that we use directly, and care about most deeply, are predicted to suffer the most as climate change is working its way up the food chain,” co-author Boris Worm, a marine biologist at Dalhousie University in Canada, said in an email.

Tropical areas, already warm, will also see the biggest losses, Cheung said.

Scientists had already thought that climate change will likely reduce future ocean life, but past computer simulations looked at only part of the picture or used only one model. This study uses six different state-of-the-artcomputer models thatgive the best big picture look yet, Cheung said.

It is hard to separate past climate change impacts from those of fishing, but past studies have shown places where observed fish loss can be attributed to human-caused climate change, Chung added.

Tittensor pointed to lobsters off Maine and North Atlantic right whales as examples of creatures already being hurt by global warming hitting the ocean.

University of Georgia marine biologist Samantha Joye, who wasn’t part of the research, praised the study as meticulous and said it is also “an urgent call for action.”

“Healthy oceans are required for planetary stability,” Joye said in an email. “Aggressive global action to slow climate change is a moral imperative.”

Seth Borenstein, The Associated Press

Like us on Facebook and follow us on Twitter.

Just Posted

Queen Charlotte name change will be a long process

Mayor says conversations still to be had with all residents

Haida Gwaii support workers strike deal with school district

New agreement will be in effect for the next three years

Northern Haida Gwaii Hospital to get secure room for psychiatric patients

Cost anticipated at close to $1 million for Masset hospital

B.C. oil tanker ban squeaks through final vote in Senate

Bill C-48 bars oil tankers from loading at ports on B.C’s north coast

Queen Charlotte explores banning single use plastics

Council seeking community input on options to reduce plastic waste

WATCH: Killer whale has the final catch in Prince Rupert waters

Fishing duel sees salmon stolen by eager orca

Fate of accused in Canadian couple’s 1987 killings in jury’s hands

William Talbott’s lawyer says DNA doesn’t prove murder

Child killed after being hit in driveway on Vancouver Island

The driver of the vehicle remained at the crash scene and is fully cooperating

Eating sandwiches, putting on makeup behind the wheel could land you a fine

RCMP say if you cause an accident while eating you could be penalized

Cat badly hurt in animal trap was likely stuck for days, B.C. owner says

Blu, a three-year-old house cat, suffered severe damage to his hind leg after being stuck in trap for days

40 cats surrendered in apparent hoarding at B.C. home

Officers found the cats living among piles of garbage and feces, suffering from fleas

Vancouver Aquarium drops cetacean ban lawsuit in new lease agreement

Ocean Wise CEO Lasse Gustavsson called the updated lease an exciting new chapter for the aquarium

Thieves steal two $40K chairs featuring gold serpents from B.C. furniture store

Chairs believed to be the only two of its kind in Canada, police said

Rising gas prices force B.C. residents to rethink summer road trips: poll

63 per cent of respondents reported gas prices are impacting their day-to-day finances

Most Read