Â鶹´«Ã½

Skip to main content

Ability of coral reefs to benefit humans has halved since 1950s, study finds

Fish and coral in a photograph captured by study co-author Tyler Eddy. (Courtesy Tyler Eddy) Fish and coral in a photograph captured by study co-author Tyler Eddy. (Courtesy Tyler Eddy)
Share
TORONTO -

Climate change, overfishing and pollution are threatening coral reefs worldwide, according to researchers, and their capacity to provide essential benefits and services to humans has drastically decreased.

published Friday in the journal One Earth offered a comprehensive look at the impact diminishing coral reef coverage has had on ecosystem services, that is, the ability of reefs to provide food and livelihoods to humans.

Global coverage of living coral has been halved since the 1950s, according to the study, and has come with a proportional decline in fish catches and abundance, as well as biodiversity.

"Coral reefs are known to be important habitats for biodiversity and are particularly sensitive to climate change, as marine heat waves can cause bleaching events," Tyler Eddy, research scientist at the Fisheries and Marine Institute, Memorial University of Newfoundland, said in a . "Coral reefs provide important ecosystem services to humans, through fisheries, economic opportunities and protection from storms."

Coral bleaching occurs when sources of stress, including changes in temperature, cause coral to expel the algae living in its tissue, which turns it white. Bleached coral is still alive, but much more vulnerable to disease and starvation.

In addition to providing a habitat for fish, coral reefs also act as a natural barrier protecting shorelines from waves and storms.

Eddy and his colleagues analyzed living coral cover across the globe against coral-associated fish catches, fish abundance, biodiversity and consumption of fishes by coastal Indigenous groups.

They found that the volume of fish caught peaked in 2002 and has been in decline since despite increased fishing efforts. The catch-per-unit effort, a metric that indicates abundance, has decreased by 60 per cent since 1950.

The team of researchers also calculated a 63 per cent decline in biodiversity with the loss of coral.

"Our analysis indicates that the capacity of coral reefs to provide ecosystem services has declined by about half globally," William Cheung of the University of British Columbia's Institute for the Oceans and Fisheries said. "This study speaks to the importance of how we manage coral reefs not only at regional scales, but also at the global scale, and the livelihoods of communities that rely on them."

The authors of the study note that achieving climate change emissions targets and reducing local impacts can help reduce stress on reefs and allow them to continue providing ecosystem services.

Maintaining these services is essential for coastal Indigenous peoples, the authors wrote, as their consumption of seafood is 15 times that of non-Indigenous populations, and therefore they rely on these habitats heavily for nutrition.

"Coral reef biodiversity and fisheries take on added importance for Indigenous communities, small island developing states and coastal populations where they may be essential to traditions and cultural practices," the authors wrote. "The reduced capacity of coral reefs to provide ecosystem services undermines the well-being of millions of people with historical and continuing relationships with coral reef ecosystems."

CTVNews.ca Top Stories

A team of tornado experts is heading to Fergus, Ont. after a storm ripped through the area Sunday night.

Why brain aging can vary dramatically between people

Researchers are uncovering deeper insights into how the human brain ages and what factors may be tied to healthier cognitive aging, including exercising, avoiding tobacco, speaking a second language or even playing a musical instrument.

Local Spotlight

For the second year in a row, the ‘Gift-a-Family’ campaign is hoping to make the holidays happier for children and families in need throughout Barrie.

Some of the most prolific photographers behind CTV Skywatch Pics of the Day use the medium for fun, therapy, and connection.

A young family from Codroy Valley, N.L., is happy to be on land and resting with their newborn daughter, Miley, after an overwhelming, yet exciting experience at sea.

As Connor Nijsse prepared to remove some old drywall during his garage renovation, he feared the worst.

A group of women in Chester, N.S., has been busy on the weekends making quilts – not for themselves, but for those in need.

A Vancouver artist whose streetside singing led to a chance encounter with one of the world's biggest musicians is encouraging aspiring performers to try their hand at busking.

Ten-thousand hand-knit poppies were taken from the Sanctuary Arts Centre and displayed on the fence surrounding the Dartmouth Cenotaph on Monday.

A Vancouver man is saying goodbye to his nine-to-five and embarking on a road trip from the Canadian Arctic to Antarctica.