TORONTO – Climate change, excessive fishing and pollution threaten coral reefs around the world, and drastically reduce their ability to provide essential benefits and services to humans, according to researchers.
one discovery Published Friday in the journal One Earth, it took a comprehensive look at the coverage of mitigating coral reefs having an impact on ecosystem services, that is, the ability of reefs to provide food and livelihoods to humans.
According to the study, the global coverage of live coral has halved since the 1950s, and has come with a proportional decline in fishing and abundance, as well as biodiversity.
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“Coral reefs are known to be important habitats for biodiversity and are particularly vulnerable to climate change, because marine ecosystems are highly vulnerable to climate change,” said Tyler Eddy, a research scientist at Memorial University of Newfoundland’s Fisheries and Marine Institute. Heat waves can cause bleaching events.” News release. “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 the coral to expel the algae living in its tissue, which turns it white. Bleached coral is still alive, but more vulnerable to disease and starvation.
In addition to providing habitat for fish, coral reefs also act as a natural barrier protecting shorelines from waves and storms.
Eddie and his colleagues analyzed live coral cover around the world against coral-associated fishing, fish abundance, biodiversity, and fish consumption by coastal indigenous groups.
They found that the amount of fish caught peaked in 2002 and has declined despite an increase in fishing efforts. Catch-per-unit effort, a metric that indicates abundance, has decreased by 60 percent since 1950.
The team of researchers also calculated a 63 percent decline in biodiversity with the loss of coral.
“Our analysis indicates that the ability of coral reefs to provide ecosystem services has declined by about half,” said William Cheung of the University of British Columbia’s Institute for Oceans and Fisheries. “This study speaks to the importance of how we manage coral reefs not only on a regional scale, but also on a global scale, and the livelihoods of the communities that depend on them.”
The study’s authors noted that achieving climate change emissions targets and mitigating local impacts could help reduce stress on reefs and allow them to continue to provide ecosystem services.
It is essential for coastal indigenous peoples to maintain these services, the authors wrote, as seafood consumption is 15 times that of non-indigenous populations, and so they are heavily dependent on these habitats for nutrition.
“Coral reef biodiversity and fisheries carry additional 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 diminished capacity of coral reefs to provide ecosystem services undermines the well-being of millions of people with historical and ongoing relationships with coral reef ecosystems.”