BY EMILY PETSKO
APRIL 30, 2020
e can rebuild marine life and restore much of the world’s oceans in just 30 years if we take action to protect species and ecosystems at risk. A team of marine scientists from 10 countries reached this conclusion after reviewing past ocean recoveries following conservation interventions.
“This provides a window of opportunity to mitigate existing pressures over the next decade while supporting global initiatives to achieve substantial recovery of marine life by 2050,” scientists wrote in their paper, published this month in the journal Nature. “We are at a point at which we can choose between a legacy of a resilient and vibrant ocean or an irreversibly disrupted ocean, for the generations to follow.”
Oceana is already working on many of the next steps that scientists recommended – namely reducing overfishing and bycatch, as well as protecting vulnerable species and habitats. Global management reforms could help many depleted fish stocks return to a healthy enough biomass to support sustainable fishing in just 10 years.
As one of the authors of that paper, Oceana Science Advisor and marine ecologist Dr. Boris Worm said their paper “provides very clear recommendations on how [recovery] can be done in a science-based and effective way.” In a recent conversation with Oceana, he explained what they learned and why it’s encouraging news for our oceans.
What prompted this review of ocean recoveries?
This was prompted by our observation that many of the conservation and pollution control measures we were collectively aware of had borne results, and that this often happened within a reasonable time frame. We were curious as to whether there were any generalizable patterns in these recovery data.
Did any of the findings surprise you?
Yes, I was surprised how quickly and strongly some species and ecosystems recovered. For example, humpback whales in the southern hemisphere had been recovering by 10-13% per year since the late 1960s and increased from several hundred to an estimated 40,000 individuals today. That is pretty surprising for a large, long-lived creature. Another example is the recovery of fishery resource species on Georges Bank, after half of it was closed to fishing in 1994. The results for scallops and haddock, for example, are quite spectacular and demonstrate the resilience that is inherent in many ocean ecosystems even today.
Of all the marine life recoveries that you’ve encountered, did any of them strike you as especially inspiring?
I recently returned from Raja Ampat, Indonesia, where I witnessed the recovery of reefs after intense blast fishing and poaching that was rampant up to the year 2000. Since then, a community-based marine protected area (MPA) and fisheries tenure program has led to the truly remarkable recovery of the reefs – and the fish, shark, and turtle species that depend on them – and has brought about new revenue streams for local people. One example of this is dive tourism. I could not believe the growth of healthy coral in places where even 10 years ago I saw a lot of rubble.
Why are mangroves and salt marshes good examples of habitat restoration projects?
There have been hundreds of attempts to restore damaged salt marshes and mangrove forests, and in reviewing those we found that they often bore spectacular results, not just in restoring the ecosystems but also the essential ecosystem services that they provide to us. These include their capacity to buffer storms and floods, and protect our coastlines from some of the effects of climate change and sea level rise.
Your team wrote that climate change is the “critical backdrop against which all future rebuilding efforts will play out.” To what extent will our efforts to mitigate greenhouse gas emissions determine the future health of our oceans?
Climate change is the fastest rising threat to ocean ecosystems, and as such it needs to be brought under control if rebuilding and conservation efforts are to bring about the expected results. This is especially clear in coral reefs which could largely disappear by the end of the century if climate change, ocean warming, and ocean acidification are not mitigated in accordance with the Paris targets.
What other pressures need to be alleviated for ocean abundance to be restored by 2050?
Overfishing needs to be brought under control, and destructive and unselective fishing practices need to be replaced by smarter ways of harvesting. Widespread pollution with excess nutrients from fertilizer use and human wastewater, as well as persistent synthetic chemicals, including plastics, must not enter the ocean anymore. And efforts to restore damaged ecosystems need to be scaled to a global level.
Your team wrote that taking steps to rebuild marine life is not only a “smart economic objective,” but also an “ethical obligation.” Why did you feel it was important to include this moral call to action?
The extinction of species and the destruction of vital ecosystems is a moral failing as much as an ecological and economic disaster. It would be wrong to disregard this ethical dimension, in my view, especially since it is strongly felt by so many people. And because of that groundswell of dissatisfaction with the status quo, in 1992 under the Convention of Biological Diversity, humankind collectively decided to stop and reverse these trends. Our paper indicates that now we are beginning to see some of the fruits of these efforts, at least in some places.
For people who don’t live or work near a coast, the connection between humans and the ocean isn’t always apparent. In what ways would a restored ocean benefit people?
Quite simply, the ocean is an essential part of our planetary life support system that provides for all life on earth, no matter whether it’s on land or in the sea.