The economic theory used by investors is showing early signs of helping save coral reefs.
Modern portfolio theory, a mathematical framework developed by the economist Harry Markowitz in the 1950s to help risk-averse investors maximize returns, was used by researchers at Australia's University of Queensland to identify the 50 coral sanctuaries that are most likely to survive the climate crisis.
The study suggests that the most promising projects to protect priority reefs should be targeted for investment. The gains go beyond positive ecological outcomes and include important social, economic, health and nutrition benefits for communities, according to partners, organisation and funders interviewed by Blue Earth Consultants.
Prof Ove Hoegh-Guldberg, a climate scientist at the University ofQueensland, who helped lead the "50 reefs" project, said: "It's essentially a strategy to help us make decisions about what to protect, if we are to have corals at the end of
He said that it was the best chance of having a long-term future for coral reefs.
Coral reefs are in dire need of repair. 70% to 90% of today's corals would disappear if global heating was limited to 1.5C above pre-industrial levels.
There is coral at Ko Losin. In the past decade, about 14 percent of coral reefs have been lost. There is a photograph of Jorge Silva.
A study in October found that coral reef health has been lost in less than a decade due to rising sea- surface temperatures.
Portfolio theory aims to reduce risk while maximizing returns, according to Hoegh-Guldberg. It is treating the environment as an investment opportunity.
The strategy came out of a meeting of scientists at the Hawaii Institute of Marine Biology in 2017, which used the theory to help scientists choose a balanced portfolio of coral reefs.
Hoegh-Guldberg said there are hundreds of these reefs across the planet. Which one do you pick, so that you concentrate on it?
Dr Hawthorne Beyer, a fellow at the University of Queensland, said that people in the business world would get it immediately if they talked to them. It makes a lot of sense. Ours was the first to apply it on a global scale.
The scientists divided the world's coral reefs into "bioclimatic units" of 500 sq km. They used 174 metrics, in five categories, including temperature history and projections, ocean acidification, invasive species, and connectivity to other reefs. They used a process called "scalarisation" to make estimates for each BCU. The widest range of possibilities was captured by this. We don't know which metrics are the best at predicting risk.
The team used MPT to quantify threats and identify the best options for preservation, while allowing for uncertainty over future risks from climate change.
He said that you don't want to put all your eggs in one basket, or bet on one measure of risk, when you have massive uncertainty about what the risks will be.
A clownfish is on coral in the Great Barrier Reef, which was identified as a priority area by the study. William West is pictured.
The project identified reefs in the Middle East, northern and eastern Africa, Australia, the Caribbean, Pacific islands, South America, and south-east and south Asia. The Great Barrier Reef in Australia, the Egyptian and southern Red Sea, and parts of the "coral triangle" around Indonesia, Malaysia, and the Philippines are included. Hawaii and the Barrier Reef were excluded from the model due to the criteria for climate and connection.
The project has been funded by a number of organizations. At least 26 organizations have been helped by the 50 reefs-inspired approach, and eight funders have prioritised 60 coral reef ecosystems across more than 40 countries.
Coral reefs are home to at least a quarter of all marine species and support hundreds of millions of people. Five threats to coral have been focused on by the study, including fishing, non-point source pollution, wastewater pollution, and coastal development.
Emily Darling, director of coral reef preservation at the Wildlife Conservancy, said that part of the benefit was having a clear plan of where to focus their efforts.
One of the biggest benefits of the 50 reef approach is that it gives reefs a fighting chance by showing that climate change is a critical threat to coral reefs.
The WCS has $18 million in funding for work in 11 countries to help communities reduce pressure on the precious ecosystems on 21 of the 50 reefs.
We are looking at non-climate threats such as overexploitation, destructive fishing, unsustainable tourism, coastal development, water pollution. We ask what the top local pressures are. That is how we identify which intervention to use.
WSC has supported a no-take marine protected area between Kenya and Tanzania to protect the corals from the pressures of global warming.
She said that by doing that, we will safeguard coral reef biodiversity, as well as the whales, spinner dolphins, the dugong, and the fish.
The Guardian reported last year on the "happy coral" sanctuary in Tanzania, where coral species have thrived despite warming events that have killed nearby reefs.
