Sharks might face serious feeding challenges in the future as ocean acidification threatens to weaken their teeth, crucial tools for hunting and survival. A new study found that rapidly acidifying oceans could damage shark teeth faster than they are replaced, potentially affecting both shark populations and the broader marine ecosystem.
Shark jaws contain multiple rows of teeth, which are continuously replaced. Researchers tested 60 naturally shed blacktip reef shark teeth in artificial seawater at current ocean pH (8.1) and projected future pH (7.3). After eight weeks, teeth in the more acidic water suffered roughly double the damage, including increased root corrosion and altered serrations.
Ocean acidification, caused by CO₂ absorption, could lower average ocean pH to 7.3 by 2300, with profound implications for marine life. Dental stress adds to existing threats such as prey shortages from overfishing. Even moderate acidification could affect species with slower tooth replacement or fewer rows of teeth.
Researchers note that sharks might adapt by increasing tooth replacement or strengthening teeth, but further studies are needed to determine how corroded teeth affect feeding efficiency. Previous work has shown acidification also harms shells, corals, and shark denticles, emphasizing the broader risks to ocean predators. Reducing CO₂ emissions is critical to mitigate these impacts.
