Sharks may soon have more to worry about than overfishing—new research suggests their teeth are at risk of erosion due to ocean acidification. A study published in Frontiers in Marine Science reveals that as oceans absorb increasing levels of carbon dioxide, the resulting drop in pH levels could cause shark teeth to corrode faster than they can regenerate.
Researchers from Heinrich Heine University in Germany tested this by soaking 60 recently shed teeth from blacktip reef sharks in controlled tanks. One set simulated today’s ocean conditions, while the other mimicked the much more acidic environment expected by the year 2300. After just eight weeks, the teeth in the more acidic water showed twice as much damage, including worn serrations and root erosion.
Lead author Maximilian Baum notes that this dental decay could compound the challenges sharks already face, such as declining food sources due to overfishing. While the harmful effects of acidification on corals and shellfish are well-documented, this study extends the concern to top predators with highly mineralized teeth.
Some shark species might adapt by speeding up tooth regeneration, but those with slower tooth replacement cycles could be more vulnerable. That, in turn, could ripple through marine ecosystems. Experts caution, however, that more research is needed to determine whether the observed tooth damage would actually impair sharks’ hunting abilities.