Thanks to a combination of greenhouse gasses, over-fishing, climate change and pollution, the entire marine food chain is at serious risk of collapsing by 2050, according to the results of some startling new scientific research.
The study, which was led by Australia's University of Adelaide and published in the Proceedings of the National Academy of Sciences, looked at 632 already-published experiments from oceans across the globe collectively, and found that a combination of factors is chipping away at the number and variety of marine species in the world at an alarming rate.
A report from The Guardian notes that part of the problem is that oceans are getting more and more acidic due to the release of carbon dioxide from fossil fuels being burned, and explains that this "acidification" causes changes in the pH of the water, which "will make it hard for creatures such as coral, oysters and mussels to form the shells and structures that sustain them." In other words, the water is now so acidic it literally eats away the life-sustaining shells of tiny sea creatures...which feed bigger sea creatures...which feed us.
In addition to acidification, the oceans are also getting significantly warmer as a result of climate change, which the Guardian notes is already "changing the behavior and habitat range of fish" with visibly damaging effects all the way up the food chain. The researchers observed that very few marine species are currently showing any signs of being able to adapt to/deal with the rising temperatures of ocean waters.
“There is more food for small herbivores, such as fish, sea snails and shrimps, but because the warming has driven up metabolism rates the growth rate of these animals is decreasing,” associate professor Ivan Nagelkerken from Adelaide University told The Guardian. “As there is less prey available, that means fewer opportunities for carnivores. There’s a cascading effect up the food chain."
The Guardian notes that "Since 2014, a massive underwater heatwave, driven by climate change, has caused corals to lose their brilliance and die in every ocean. By the end of this year 38 percent of the world’s reefs will have been affected. About 5 percent will have died. Coral reefs make up just 0.1 percent of the ocean's floor but nurture 25 percent of the world's marine species."
We rely on marine food chains not only for seafood, but also for medicines and economic stability, so the impact of a marine food chain collapse would be devastating. If we want to stop it, scientists say we'll need to slow climate change by reducing our reliance on fossil fuels, stop over-fishing, and clean up pollution in the oceans.
“These effects are happening now and will only be exacerbated in the next 50 to 100 years,” Nagelkerken said. "But if we reduce additional stressors such as over-fishing and pollution, we can give species a better chance to adapt to climate change.”