A Nature-based Solution for Resilient Oceans
June 24, 2022
As carbon sinks, oceans play an important role in mitigating the effects of climate change. Considered as the main source of life on Earth, oceans are home to billions of species and contribute to the livelihood of a third of humanity. This year’s United Nations World Oceans Day, on 8 June 2022, theme is the Revitalization: Collective Action for the Ocean.
Unfortunately, persistent pressure from human activities is accelerating the warming and eutrophication of oceans, resulting in the melting of polar ice caps and the spread of dead zones around the world. Today, ocean heat has reached record levels. If nothing is done to collectively reverse this trend, vital ecosystems such as coral reefs will disappear by 2050.
During the 2016 global coral bleaching event in Mauritius, 40 percent to 50 percent of the total live coral cover was impacted, while over 60 percent of sites in Seychelles experienced high or extreme bleaching, with a coral mortality rate of approximately 30 percent. This impact is especially alarming for Small Island Developing States such as Mauritius and Seychelles which depend on the ecosystem services of their lagoons for livelihoods.
According to the International Coral Reef Initiative (ICRI) Plan of Action 2021-2024, actions should be taken to “understand and promote the resilience of coral reefs and related ecosystems through policies and conservation practices that encourage resilience-based management and recovery of coral reefs worldwide”.
Adaptation through Coral reef rehabilitation
The United Nations Development Programme invests in the protection of coastal communities, fisheries and marine ecosystems, including coral reefs from climate change impacts, particularly disaster risks, through nature-based climate solutions such as mangrove restoration, coral reef rehabilitation, and marine protected areas.
In 2020, the UNDP started the implementation of the ‘Restoring Marine Ecosystem Services by Restoring Coral Reefs to Meet a Changing Climate Future’ project (known as Coral Restoration project) in the Republic of Mauritius and the Republic of Seychelles. Funded by the Adaptation Fund (AF), this 6-year project has for overall objective to reduce the impacts of climate change on local communities and coral reef-dependent economic sectors. The project also aims at improving food security and livelihoods and mitigate disaster risk through active restoration of coral reefs degraded by coral bleaching. The project’s objective includes the rehabilitation of at least 3.2 hectares of degraded sites in Mauritius and 2.5 hectares in Seychelles. This also entails a positive outcome for at least 800 people, as a result of new and sustained employment and business opportunities.
Heat Resilient Corals: A Nature-based solution
Over the past years, several methods have been developed for coral restoration. Traditionally, corals which have resisted past bleaching events were used as mother colonies for propagating ocean nurseries and coral restoration activities. However, the concern with this method is that there is no certainty as to whether or not these restoration sites will survive future coral bleaching events.
One of the initiatives under UNDP-AF Coral Restoration project is to determine the heat resilient corals in Mauritius, Rodrigues and Seychelles for future restoration activities. This scientific approach, which began in January 2022, involves the identification of coral reefs that have been exposed to recurrent thermal stress and which have proved to be tolerant against heat.
The genomic studies will help establish which corals in Mauritius, Rodrigues and Seychelles are more resilient to heat, and can subsequently be propagated in ocean and land-based nurseries. A higher survival rate of restored corals following heat waves is expected with this technique.