Bringing to extinction some of the most unique animals in the world and modifying oceanic trophic networks
New research from the University of North Carolina at Chapel Hill, United States, concludes that the majority of marine life in the Marine Protected Areas (MPA) will not be able to tolerate the warming of ocean temperatures caused by greenhouse gas emissions greenhouse. MPAs have been established as a refuge to protect threatened marine life, such as polar bears, penguins and coral reefs, from the effects of fishing and other activities, such as the extraction of minerals and oil.
The study, which was published two days ago in the journal Nature Climate Change, ensures that, with the continuous “normal” emissions of greenhouse gases, the current protections will not matter, because, by the year 2100, the warming and reduction of the concentration of oxygen will make the AMP uninhabitable for most of the species that currently reside in them.
The study concludes that such rapid and extreme warming, such as that envisaged for a scenario in which the increase in temperature would be of the order of 2.8 degrees, would devastate the species and ecosystems currently located in the MPA, which could lead to to the extinction of some of the most unique animals in the world, the loss of biodiversity and changes in oceanic trophic networks.
It could also have considerable negative impacts on the productivity of fishing and on tourism revenues. Many of these marine species exist as small populations with low genetic diversity that are vulnerable to environmental change and are unlikely to adapt to ocean warming.
The study also calculated the year that MPAs in different ecoregions would cross critical thresholds beyond which most species could not tolerate the change. For many areas in the tropics, this will happen, for example, in the middle of the 21st century. The research revealed that there are 8,236 marine protected areas worldwide, although they only cover approximately 4% of the ocean’s surface.
It is estimated that the average sea surface temperatures within the Marine Protected Areas will increase by 0.034 degrees per year. It is anticipated that MPAs in the Arctic and Antarctic will warm up especially rapidly, threatening many marine mammals, such as polar bears and penguins. Other MPAs with higher risk are located in the northwestern Atlantic, and the recently designated no-catch reserves in the north Galapagos, Darwin and Wolf islands.