Our generation may be the last to enjoy snorkeling in coral reefs, deep-sea fishing or simply enjoy a good salmon steak. Scientists often describe our oceans as the planet’s circulatory system. In addition to providing vital resources, it produces half of our oxygen, drives our weather system and regulates our atmosphere. But now ocean life is facing a mass extinction.
A panel of distinguished marine scientists met at Oxford University, England, in April to discuss the impact of human activity on the oceans. The meeting, led by the International Programme on the State of the Ocean (IPSO), examined the combined effects of pollution, acidification, ocean warming, over-fishing and depleting levels of oxygen in the water.
These factors are present in the ocean today, and are already wreaking havoc. The mass “coral bleaching” in 1998 that killed 16% of all the world’s tropical coral reefs were caused by warmer temperatures and rapid changes in ocean chemistry. Over-fishing has reduced some commercial fish stocks and populations of by-catch species by more than 90%.
The panel concluded that the conditions in our oceans are similar to those that caused “previous major extinctions of species in Earth’s history”. Many marine species and even ecosystems, including coral reefs, may die out within a generation. Rising water temperatures and hypoxia, a loss of oxygen related to the ocean’s absorption of large quantities of carbon dioxide, are blamed as the main cause for the extinctions.
Alex Rogers, professor of Conservation Biology at the Department Of Zoology, University of Oxford, told CNN: “The rate of change we are seeing in the quantities of carbon dioxide going into the atmosphere and then being absorbed into the oceans is so great that it is difficult to compare what is happening now with what has happened in the past but we do know that past disturbances in the carbon cycle have been a feature of mass extinction events.”
If there is a silver lining to this prophecy of doom, it is that thanks to years of research by marine scientists, we know what is causing the mass extinctions.
Our generation must be ready to acknowledge the treasures we share in our oceans. We must take real efforts to reduce carbon emissions, pressure polluters everywhere to change their ways and choose to eat sustainable seafood. We must rekindle a respect for the natural world, and what it can provide for us.