Carlos Duarte, oceanographer, professor of Marine Sciences at the King Abdullah University of Science and Technology, in Saudi Arabia, was recently in Cala Clara, in Mallorca, where he was surprised by the abundance of large rock fish, octopus, crabs and marine plants such as Posidonia. Duarte talks about what he calls "the covid generation of marine life", born in a period in which human pressure on the fauna of the sea would have given rise to reproductive success and facilitated their recovery. Sightings of juvenile specimens of different species of sharks, such as blue sharks, in waters close to the beaches would be some demonstrations of that generation of species that were born when man "disappeared" momentarily or reduced his pressure on life in the sea. "The covid is leaving a mark on a recovery episode in marine life that can have long-term effects," he says.
Is this recovery taking place in Spain, around the world?
Not only in Spain, it is appreciated throughout the Mediterranean and throughout North America. News of this recovery and abundance of sharks and other species comes from all over the world, but they appear as local phenomena and nobody is connecting that news. I pose it as a hypothesis. But it would require an effort to sample, slaughter animals, see how old they are, and test them. But the most plausible hypothesis is that it has been the respite that the covid has given.
Is it your impression? Is it a punctual recovery, in the pause, limited to the confinement stage?
It is not just my impression, it is something that I connect to what is known on social networks and the media around the world of similar observations. There are hundreds of evidences of reduced human pressure and increased reproduction of marine animals. We collected information between March and October 2020 on the response of ecosystems on land and in oceans to confinement. In some countries the lockdown has continued for a long time. China, Japan, Korea and many countries in Asia were in lockdown for most of 2021 as well. Globally, the lockdown peaked at 60% of the human population in 2020, but in some small countries that lockdown has lasted nearly two years.
What would the impact of this pause be in the long term?
No one has done a study on what the long-term consequences of that situation have been. In science we work from hypotheses, and the hypotheses are based on some observations and that generates what can be knowledge. What we are now appreciating are observations that could encourage a systematic study to verify all this. It is a hypothesis that is based on all that data that we collected in the year 2020.
Sometimes you hear testimonies that point out, for example, a greater presence of sharks or turtles...
In the United States, the greatest abundance of sharks in history is being observed, or turtle spawning where they have never occurred or there is memory of their occurrence, but are reported as local anomalies. We had an international congress in Mallorca in June 2023, with 3,000 marine scientists, and right on the promenade a turtle spawned, without any memory of that having happened before, and two weeks later it spawned another. It turns out that the same thing happens in other local newspapers around the world. No one has connected these observations and no one has formulated the hypothesis that all this is part of a global phenomenon that is supported by the 2020 data. They are opinions that allow formulating a hypothesis. What should be checked
What would you highlight in that balance sheet?
We receive reports of a greater presence of sharks or dolphins, of animals that are about two years old.
And what about the turtles?
Turtle spawning has been reported in various places. In the case of sea turtles, what has happened is that during the anthropause there has been a recovery of that habitat that was being lost, and that is what we are seeing. We will see the response of the turtles born during the anthropause when they spawn in 30 years. The Covid-19 generation will not manifest itself to its full extent for several decades when hatchlings hatched during the anthropause reach reproductive maturity and return to the beaches where they hatched to spawn.
What species have been able to have a greater recovery?
Coastal species, those that have habitats in the coastal zone, rock fish, coastal invertebrates, underwater meadows or oceanic species that temporarily use the coastal zone, such as turtles, which use them to spawn, or even seabirds. And I think that pause would have affected population dynamics. In contrast, species in the open ocean will not have noticed any change during the anthropause. significant because oceanic maritime trade was reduced little.
In that pause they have been able to reproduce with greater tranquility.
This is documented in the case of some of the most important turtle nesting sites, such as Florida. At Gahirmatha Beach in India, which is home to the world's most endangered sea turtle, the olive ridley, the number of baby turtles hatching in 2020 was between 100 and 1,000 times higher than previously observed, as it is a very frequented area and with the passage of vehicles that crushed the nests. That there was no one on that beach for months was key. There has also been an expansion of the habitats of species that had moved away from the coasts due to impacts and noise. But the long-term consequences of that pause in human impacts have not been tracked. The reproductive success of that specific pause is a window that could have had long-term consequences, although it is a hypothesis. Those turtles I'm talking about can have a longevity of 80 or 90 years. We are talking about something similar to the 'baby boom' in our generation, which took place after the world war.
We have forgotten about the covid...
We have forgotten all that happened three years ago, but suddenly the ocean tells us that something has happened. Sightings of marine animals on the coast and abundance of these animals remind us of what happened in 2020, and the speculations that were made then about the consequences that it could have in the long term.
Regarding the structural measures for the recovery of marine life, where should they go?
Here it is key that in December 2022 the Kunming-Montreal Global Framework for Diversity was approved, which sets the objectives of the Convention on Biological Diversity for the decade. These include stopping the loss of biodiversity in this decade, with objectives such as protecting 30% including international waters; now we only have 8.5% protected, and we had to reach 10% in 2020, which we did not do. Another agreement was the commitment to recover 30% of degraded habitats by 2030, something that the Nature Law of Europe, approved by a narrow margin in parliament, does not reach.
The agreement of the European Parliament was a very complex one...
And the European Union, which was the promoter group with the greatest ambition in Montreal, when it agreed to this law in the European Parliament to consolidate it, only dared to pass it with 20%, and not with 30%.
¿Disappointed?
I note that eight months after the Montreal agreement, Europe has already lowered its ambition, and even so it has cost a lot to pass the law. But we have a global mandate and commitment to restore 30% of degraded habitats.
Do marine protected areas serve?
Marine protected areas are an effective protection instrument, but it is passive; that is, spaces are protected from major impacts and you expect nature itself to recover. But instead, restoration is an active measure to accelerate efforts to protect marine protected areas.
So...
We have a global framework to restore biodiversity; Another thing is that we comply with it because in these international conferences objectives are set for decades and in these last two decades we have fallen far short of the goals. In 2020, only 5% of the Aichi Goals were met, and now we see that the European Union has lowered its promises.
