Ocean ecosystems are under extreme stress on several fronts including overfishing, ocean acidification, climate change and marine warming. While ocean conservation efforts often tend to focus on creating marine protected areas, researchers recently stressed the need to move beyond protection toward active recovery using a different approach: Marine rewilding.
In a new perspective paper, the researchers laid out eight key principles that can guide such rewilding.
The concept of “rewilding” is usually applied to terrestrial ecosystems, where the goal is to restore ecological processes and create resilient, self-sustaining ecosystems with minimal human interventions.
Gavin Stark, a post-doctoral researcher with the German Centre for Integrative Biodiversity Research, and his colleagues, write that one important principle of marine rewilding is that people can’t simply be fenced out of the process.
“You cannot really separate people from the rewilding process inside the marine ecosystems,” Stark told Mongabay in a video call.
Another key principle of marine rewilding is restoring food webs, which may include reintroducing top predators such as sharks. In 2024, for example, Mongabay reported on a project where eggs of the endangered Indo-Pacific leopard shark (Stegostoma tigrinum) raised in an aquarium in Las Vegas, Nevada, U.S., were shipped to nurseries in Raja Ampat, Indonesia. So far, the project has released more than 60 young sharks into the protected waters of Raja Ampat with the goal of restoring balance to the region’s coral reef ecosystem.
The authors note that along with restoring food webs, strengthening connectivity between ecosystems is also a pillar of marine rewilding. Just as fragmented terrestrial habitats make it difficult for land animals to adequately find space, mates and food, fragmented marine ecosystems are challenging for ocean wildlife.
“Protecting migration routes and ecological corridors that link coral reefs, mangroves, seagrass meadows, and deep-sea habitats helps maintain gene flow, support recolonization, and secure the ecosystem services that underpin fisheries, tourism, and cultural identity,” the authors write.
Stark said improving connectivity and marine biodiversity will, “create a resilient ecosystem that will be able to adapt to the environmental changes that we have in climate change and in pollution.”
The researchers note that other principles of marine rewilding include the need to mitigate pollution, manage invasive species and carefully monitor rewilded ecosystems so conservation efforts can be adapted as conditions change.
Ultimately, marine rewilding centers on rebuilding biodiversity and ecological function while recognizing that people and coastal communities are also an integral part of marine ecosystems, the authors add.
For Stark, the goal isn’t to recreate an ecosystem exactly as it existed in the past, but to improve the current ecosystems so they can be self-sustaining and better able to respond to future disturbances.
“These guidelines are like a blueprint to just start something that maybe will allow this ecosystem to really flourish. But we need to actually start to implement it,” he said.
Banner image: An adult zebra shark (Stegostoma tigrinum) from Western Australia. Image courtesy of Rebecca Bateman-John.
