In the short term, the fishing must be regulated and the pollution of the sea with sewage must be stopped. In the long term, to save life in the sea, carbon emissions must be stopped

Says Nancy Knowlton, the chief marine biologist of the Smithsonian Institution and the Museum of Nature in Washington, in a conversation with the science site. Knowlton is currently visiting Israel and will participate in a conference at Tel Aviv University

The oceans are in trouble, but just as it is difficult for people to understand that even the air, which seems infinite, is limited, so it is also difficult to explain to them that the sea, and in particular the animals and plants living in it or from it, are suffering as a result of human activity at all levels. This is what emerges from a special conversation for the scientist website with Nancy Knowlton, a veteran researcher of life in the sea and currently the Sant Chair for Marine Science at the Smithsonian Institution, whose familiar arm to us is the Museum of Natural History in Washington.
Today, Wednesday, Knowlton will participate in the conference on taxonomy, biological diversity, the expected global environmental change and its impact on society in Israel, organized by Tel Aviv University in collaboration with the Israel Society for Taxonomy.

One of Knowlton's tasks is to expand the display of the ocean hall in the museum, with a large display on the human impact on the oceans: overfishing, water pollution, climate change and their impact, the most prominent of which is the increase in sea acidity, and the issue of invasive species. "In the new display, we will tell about the history of man's relationship with the sea, about the ancient dependence of humans on the resources of the sea and how humans have changed the sea.

Will there be no fish in the sea in 2050?
"There is a debate about this, but there is no doubt that if we continue with all these things - overfishing, climate change, acidity, etc., we are affecting the chemistry of the seas, the temperature of the sea in a bad way. We are doing a big experiment on the oceans, which make up 70% of the surface and 95% of the usable area - and even the volume: we have all the depths of the ocean, the volume of the ocean compared to the volume of the biosphere on land is much larger."

What is being done to stop the problem in the oceans?

"In the short term, we need to create protected marine areas, where fishing will be monitored. In a developed country like Israel this means areas where there will be no fishing at all so that there are places where the fish can reproduce. In developing areas, you need to rotate between fishing grounds.
As for pollution - the problem is in the connection between the sea and the land. Policies must be adopted regarding afforestation to prevent siltation, as well as to prevent the flow of sewage into the sea to keep the water clean and the fish healthy. This will help not only the fish. Healthy fish help corals because they eat the algae that hinder their development. These are entire ecological environments and not just the fish.
In the long term, if we do not reduce the level of carbon emissions in the atmosphere, the days will be too hot and acidic and a lot of damage will be caused. Just for example, any creature that grows in oysters will suffer from the acidity."

"The warming of the sea water is also a danger and we will see it initially in the coral reefs which are like canaries in coal mines - a sign of the distress of the marine biosphere."

The whole earth is a global system, the air moves so fast. It is not only the air pollution and carbon emissions that are absorbed by the sea, but everything on land eventually reaches the sea through the river system. It is less extreme in Israel because you don't have big rivers. But in general rivers bring pollution to the sea.

Are you optimistic about the success of the campaign, in particular against carbon emissions?

"People oppose changes and especially the identification of the problems as arising from the activities of corporations, but science does not dictate policy. What the scientists can say if we do this is what will happen. Science provides the information about the consequences, but policy is the result of discussions. Scientists can contribute to the debate. The opponents should be asked if we want to live in a healthy world or in one big parking lot? I have my own opinions as a citizen of the planet, but as a scientist I can say that if you want a healthy marine environment that supports fishing and tourism you have to limit fishing and maintain water quality in the short term and in the long term you have to solve the problem of carbon dioxide emissions because from a physical and chemical point of view it will not improve with the oceans. If the oceans matter to us, this is what the scientists tell you to do. People need to recognize the value of the oceans, for example for those who come to places like Eilat to dive. They won't come if it's a marine desert and a garbage can."

In conclusion, Knowlton mentions two of the greatest experts in the field who work from Israel - Dr. Maoz Payne from Bar-Ilan who studies the effect of acidity on the corals in Eilat. and Prof. Yossi Loya from Tel Aviv University (member of the Academy of Sciences) whom Knowlton considers one of the greatest marine biologists in the world.