A new study published Sunday in Nature Climate Change finds that ocean acidification could cause the Southern Ocean Antarctic krill population to crash by 2300, meaning dire consequences for whales, seals, penguins, and the entire ecosystem it supports. In addition to devastating ecosystem effects, a collapse in krill populations could have serious economic implications, as the species represents the region’s largest fishery resource.
Antarctic krill is a keystone species in the fragile Southern Ocean ecosystem. Predators such as whales, seals, and penguins rely on Antarctic krill as their primary food source. Without a stable base of krill to support these top predators, each of the links in the food web would deteriorate, potentially inducing entire ecosystem collapse. When you factor in the immediate economic hit that regional fisheries will surely face as well, krill population decline becomes a problem far larger than the mere centimeters-long species itself.
The study reports that important habitats in the Southern Ocean are likely to become high-risk areas for Antarctic krill within as little as a century. But how exactly does ocean acidification play a role? Oceans have always absorbed carbon dioxide from the atmosphere, and act as vital buffers against climate change, but as man-made carbon dioxide emissions continue to rise at an alarming rate, the oceans are now changing too fast for some animals to adapt. The result is a more acidic ocean. The Southern Ocean is particularly vulnerable because cold waters hold higher levels of carbon dioxide than warmer, more tropical waters. For Antarctic krill, whose eggs naturally sink to deeper, colder waters to hatch, the high carbon dioxide results in lower hatch rates, and will likely spell disaster for their populations and subsequently the entire Southern Ocean ecosystem.
The only truly effective way of combating ocean acidification and climate change is to reduce carbon dioxide emissions. Oceana is working to reduce the cause and effects of ocean acidification by promoting clean, renewable offshore wind development and fighting to stop the expansion of offshore oil and gas drilling. If we do not act immediately to combat ocean acidification and climate change, our oceans will reach a tipping point at which we can no longer prevent ecosystem collapse. Please help Oceana save the beautiful Southern Ocean ecosystem.
This article was written by Colin Cummings for Oceana.org