Scientists have laid out what’s required to rebuild marine life by 2050

  Last updated April 8, 2020 at 11:38 am


Researchers say we’re at a point at which we can choose between a legacy of a resilient and vibrant marine life or an irreversibly disrupted ocean, for the generations to follow.

marine life_sharks_ocean life

Sharks and large marine predators have experienced significant decline, but evidence shows their stocks can also be rebuilt with the appropriate protection measures. Credit: Manu San Felix, National Geographic

Why This Matters: For the sake of our oceans, let’s go further.

It’s not too late to rescue global marine life, according to a study outlining the steps needed for marine ecosystems to recover from damage by 2050.

Writing in the journal Nature, scientists have warned that the ocean’s capacity to sustain human wellbeing – by mitigating climate change and providing food, water and oxygen – is at a critical junction.

“We are at a point where we can choose between a legacy of a resilient and vibrant ocean or an irreversibly disrupted ocean,” says lead author Carlos Duarte from the King Abdullah University of Science and Technology, in Saudi Arabia.

Catherine Lovelock from the University of Queensland, who was also involved in the study, says they found many components of marine ecosystems can be rebuilt if we try harder to address the causes of their decline.

“People depend on the oceans and coastal ecosystems as a source of food, livelihoods, carbon capture and, thanks to coral reefs, mangroves and other coastal ecosystems, for protection from storms,” Lovelock says.

“But people are having enormous impacts globally and it’s time to do what we must to ensure our oceans are healthy and vibrant for generations to come.”

The United Nations Sustainable Development Goal 14 recognises the urgent need to “conserve and sustainably use the oceans, seas and marine resources for sustainable development”.

There are issues to overcome to save marine life

The research highlights that climate change is a main issue that needs to be tackled.

“We can only rebuild the abundance of the world’s marine if the most ambitious goals within the Paris Agreement are reached,” says Lovelock.

The researchers identify nine factors central to reviving marine life, salt marshes, mangroves, seagrasses, coral reefs, kelp, oyster reefs, fisheries, megafauna and the deep sea.

They also outline six complementary interventions called “recovery wedges” that include a suite of strategies under the themes of protecting species and spaces, harvesting prudently, restoring habitats, reducing pollution and mitigating climate change.

“Conserving coastal wetlands could improve food security for the millions of people who depend on them, and reduce the dangers of storm damage and flooding – saving billions of dollars.”

“Mangroves, saltmarshes and seagrasses can store carbon in their soils and biomass which can help mitigate climate change.”

Also: If we want to control greenhouse gases then we need to think ‘blue carbon’

“They provide so many benefits to coastal society that investing to rebuild them is a no-brainer.”

There are also other measures that can be taken, like reducing relevant pressures, safeguarding places of remaining abundances as well as recovering depleted populations, habitats and ecosystems.

But it’s not a smorgasbord that can be picked at selectively or passively. The researchers argue that the goals need to be adopted wholly, and that the focus should be not just conservation but actively reviving dwindling species and ecosystems to sustainably feed and support the growing human population.

It is not possible to recreate ecosystems

Duarte adds the goal is not to recreate historical ecosystems.

“That’s no longer possible – rather we should improve on the status quo by re-building stocks of depleted marine populations over coming decades,” he says.

“The elephant in the room is climate change, especially for vulnerable ecosystems like coral reefs and kelp beds.

Also: Corals can’t adjust to acidic oceans

“There’s no one silver bullet – we have to address the root causes of ecological collapses.

“It’s not enough to reduce pollution or fishing pressure as the future of the ocean also depends on how rapidly greenhouse gas emissions are reduced.”

Recent interventions have led to success

Although human activities have had devastating impacts on marine life over the 20th century, the team drew on resilient responses of sea creatures, habitats and ecosystems to conservation efforts to demonstrate how they can be revived.

These include the spectacular recovery of humpback whales (Megaptera novaeangliae) in Australia, sea otters (Enhudra lutris) in West Canada and Baltic Sea grey seals (Halichoerus grypus) from the brink of extinction.

Other examples include large-scale habitat restoration of mangroves, reduction of organic pollutants and efforts to manage and recover fish stocks.

“Despite humanity having greatly distorted our oceans, recent interventions have led to a number of remarkable success stories,” Lovelock says.

The evolution of global marine protected areas compiled in the study and declared around the world shows a rapid acceleration in the 21st century. Courtesy of: King Abdullah University of Science and Technology.

Hunting regulations have become stricter through international efforts such as the Convention on International Trade of Endangered Species (CITES) and the global Moratorium on Commercial Whaling.

The researchers also point out that efforts to increase habitat protection and restoration have also expanded. In 2000 only 3.2 million km2  of the ocean was protected. Now, Marine Protected Areas cover 26.9 million km2  of the ocean.

“The world has come together before to implement moratoriums on whaling, create a Law of the Sea, prevent pollution from ships, and limit industrialised fishing – all with positive outcomes.

“For the sake of our oceans, let’s go further.”

Additional contributions from Natalie Parletta at Cosmos Magazine.

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