A new study suggests that ocean acidification could severely damage shark teeth, leaving the apex predators less able to feed effectively and potentially disrupting marine ecosystems. Sharks rely on multiple rows of rapidly replacing teeth, but increasing ocean acidity may erode their teeth faster than they can be renewed, compromising their hunting efficiency.
The research, led by Maximilian Baum at Germany’s Heinrich Heine University, tested 60 naturally shed blacktip reef shark teeth in artificial seawater tanks set to today’s average ocean pH of 8.1 and a projected future pH of 7.3. After eight weeks, teeth in the more acidic conditions suffered roughly twice as much damage, including root corrosion and dulled serrations. Such dental stress would compound existing challenges for sharks, including prey shortages from overfishing.
Ocean acidification occurs as oceans absorb carbon dioxide, lowering pH and affecting mineralized structures in marine life. Even moderate pH drops could impact shark species with fewer teeth rows or slower replacement rates. Baum noted that acidification may affect teeth across ocean predators with highly mineralized structures, not just sharks.
While some optimism remains—sharks might adapt by replacing teeth faster or repairing damage—experts stress that reducing CO₂ emissions is critical. Lisa Whitenack, a shark tooth expert at Allegheny College, added that corroded teeth may still function, but further research is needed to determine how tooth damage affects hunting performance.
