New research provides hope for marine ecosystem recovery, presenting a grand challenge to substantially rebuild our world’s oceans by 2050.

Our world’s oceans are inextricably linked to our wellbeing—a vital aspect of our economy, a viable food source, and a potential solution to our climate change and clean energy challenges. This same connection has taken its toll on marine ecosystems through pollution, overfishing, habitat destruction, and many more threats. Still, despite our negative impacts, new research indicates there is a reason for hope and an opportunity to reverse the decline of biodiversity if we act now.

A global team of marine conservationists, biologists, and economists recently published a review in the journal Nature evaluating the current status of marine ecosystems, the threats they face, and the time these ecosystems need to recover. Based on the recovery of marine populations and ecosystems following past conservation interventions, the team suggests that by 2050 we can rebuild marine life by 50-90%, in most cases, and poses a grand challenge to governments, non-profits, and society for swift conservation action to achieve this goal.

Conservation and Recovery

Over the past 50 years, the field of ocean conservation has made tremendous strides. In 1968 there were only a few hundred Humpback Whales left in existence, but today there are more than 40,000 as a result of an international ban on whaling; fisheries are increasingly managed for sustainability, and marine protected areas have expanded dramatically from 0.9% of the ocean in 2000 to 7.4% today. Conservation efforts have proven time and time again, the incredible resiliency of wildlife—reduce or remove a threat and ecosystems will thrive.

Although there have been many improvements, more progress is still necessary. Single-use plastics pollute the ocean; fishing practices kill seabirds and damage deep-sea ecosystems; climate change threatens coral reefs and alters the migratory patterns of wildlife. These problems do not have a single or straight-forward solution, but instead require a coordinated approach to bolster the structure, function, resiliency, and ecosystem services of our world’s oceans.

To develop a comprehensive approach, the researchers identified nine ecosystems and populations that are currently at risk: saltmarshes, mangroves, seagrass beds, coral reefs, kelp forests, oyster reefs, deep-sea habitats, fisheries, and megafauna. Each of these was evaluated based on six conservation actions that play a pivotal role in recovery, including protecting vulnerable habitats and species, adopting cautionary harvesting strategies, restoring habitats, reducing pollution, and mitigating climate change. Overall, the researchers found that by addressing these conservation concerns, a majority of ecosystems and populations will be substantially and almost entirely rebuilt by 2050.

Climate Change and Coral Reefs

Of the six conservation actions that researchers evaluated, mitigating climate change was deemed a high priority across the board and a critical priority for coral reef ecosystems. Based on the current pace of greenhouse gas emissions and the lack of real climate solutions, coral reefs are expected only to achieve partial recovery or a 10-50% rebound over the next three decades. Coral reef conservation is a slow and costly effort that lags other marine conservation initiatives. Immediate and comprehensive approaches to coral reef conservation are necessary, explained the researchers:

Mitigating the drivers of coral loss, particularly climate change, and developing innovative approaches to restoration within this decade are imperative to revert coral losses at scale.”

Despite these challenges, continued research into coral reef conservation points to promising and beneficial solutions from temperature tolerant corals to the benefits of invasive species removal on oceanic islands for fish biomass and coral resiliency. Each new mechanism for conservation brings hope, but only if governments and society also make strides to address climate change head-on.

Global Investment

A restoration initiative of this scope and scale will require significant financial investment. Researchers predict that the estimated cost per year to implement these conservation actions would cost at least US$10-20 billion, but the economic return would be ten-fold. The financial gains from ecotourism, job creation, and benefits of ecosystem services such as carbon sequestration far outweigh the initial cost.

The United Nations has already begun to address the connection between economic growth, human well-being, and conservation through the UN Sustainable Development Goals for 2030. These 17 components of sustainable development outline a commitment to ending poverty, improving health and education, reducing inequality, and supporting economic growth as well as the importance of resource protection, climate change mitigation, and marine conservation. Key among them is Goal 14 (Life Below Water), which encourages the “[the conservation and sustainable use of] the oceans, seas and marine resources for sustainable development.” Final negotiations for the United Nations High Seas Treaty were supposed to take place this month, which would have established guidelines for conservation and restoration of the open ocean. Although the meeting is delayed due to the ongoing COVID-19 pandemic, there is hope that it will usher in a new wave of global marine conservation.

A Grand Challenge

It is not often that we hear positive news about the health of our world’s oceans, but on occasion, research emerges that offers a glimmer of hope.

Growing numbers of success stories could shift the balance from a wave of pessimism that dominated past scientific narratives of the future ocean to evidence-based ‘ocean optimism,’ conveying solutions and opportunities for actions that help to drive positive change.”

This is one of those rare cases where researchers suggest that if we act now and aggressively tackle the primary threats to marine ecosystems, then we can make a measurable impact. Although the road to substantial marine recovery over the next 30 years will not be simple, the researchers present society with a grand challenge to address these threats and quickly. Humanity and the health of our world’s oceans are deeply intertwined, and the sooner we address these threats, the better off we all will be.

Read the paper at Nature.
Featured photo: Coral gardens at Palmyra Atoll. Credit: Kydd Pollock/USFWS