The rising issue of ocean acidification could render some of the ocean’s oldest apex predators as ‘all shark and no bite’, after a new study finds that more acidic oceans could leave many of the species with more brittle and weaker teeth.
Even the sharks’ famous ability to replace their teeth – with new ones always growing as they are using up the current set – might not be enough to stave off the pressures of the warming planet and an ocean environment left vulnerable to increasing levels of acidification.
These findings are the result of recently published research from the German institute, Heinrich Heine University in Dusseldorf in which shark teeth were examined under different ocean acidification scenarios. It found that shark teeth – “despite being composed of highly mineralised phosphates” – are still vulnerable to corrosion under future ocean acidification scenarios.
“They are highly developed weapons built for cutting flesh, not resisting ocean acid,” said the paper’s first author, Maximilian Baum, a biologist at Heinrich Heine University Dusseldorf in Frontiers in Marine Science. “Our results show just how vulnerable even nature’s sharpest weapons can be.”
Ocean acidification is the process by which the ocean’s pH values keeps decreasing, resulting in more acidic water. It is mostly driven by the release of human-generated carbon oxide. According to the article, the current average pH of the world’s ocean is 8.1. It is expected to drop to 7.3 by the year 2300, making it tens times more acidic than it currently is.
Damage to coral reefs, loss of habitats, and a threat to the survival of shell-building marine creatures are among the impacts already being felt across the ocean due to ocean acidification. Until only recently, it was deemed not to have crossed its ‘planetary boundary’, but a major study led by the UK’s Plymouth Marine Laboratory and the US’ National Oceanic and Atmospheric Administration released in June this year cited that the boundary had in fact been crossed five years ago.
As a result of the ocean acidification experienced so far, selected tropical and sub-tropical coral reefs have lost 43% of their suitable habitats, sea butterflies in polar regions have lost up to 61% of their habitat, and coastal shellfish species have lost 13% of their global coastline habitats in which they can sustain their essential biological processes.
Now, it would appear that sharks could stand to lose their teeth.