Sharks are an essential part of the ecosystems in which they live. Many operate as apex predators. They are at the top of the food chain and help keep ecosystems balanced by preventing prey animals from spreading too quickly.
When sharks have plentiful food and safety, prey creatures can and often do grow in population too quickly. In the ocean, that leads to more respiration and therefore more carbon dioxide being released into the ocean. The ocean is already getting to the point where it can’t sequester much more greenhouse gases before acid levels rise to dangerous levels.
This is a problem, because there aren’t enough sharks anymore, and you can probably guess why. The popularity of shark fin soup throughout Asia has been decried in the past for wasteful practices such as finning, in which sharks are caught, have their fins cut off while still alive, and are dumped back into the ocean to die slowly. This, coupled with a general view of sharks as dangerous to humans, has resulted in a lack of movements to protect the creatures.
But that’s coming back to haunt us, like so many other human actions over the last century or two. We’re already fighting to keep carbon emissions down, in order to prevent the global average temperature from rising any more than it already has, and reducing shark numbers isn’t helping that issue.
Large populations of fish and sea mammals don’t have other predators to keep their populations at normal levels. Without sharks, some of which don’t have large populations in the first place, prey animal overpopulation is becoming a global problem. Perhaps this information will help to move citizens and governments to take steps to conserve sharks in the wild, and help steward them back to the populations they need in order to do their part against climate change.
Dr. Rick Stafford of the Department of Life and Environmental Sciences at Bournemouth University is the lead author of the study. Stafford says “The research really demonstrates the far-reaching consequences of overfishing and of barbaric practices like shark finning. We need to be much more aware of the importance of marine ecosystems and how they can affect all of us.”