Evidences on alterations in skeleton composition and mineralization in a site-attached fish under naturally acidified conditions in a shallow CO2 vent

Abstract

Background: Ocean acidification may affect fish mineralized structures (i.e. otoliths and skeleton).

Methods: Here, we compared the elemental composition of muscle and skeleton and the mineral features of skeleton in the site-attached fish Gobius bucchichi naturally exposed to high pCO₂/low pH conditions in a shallow CO₂ vent with fish of the same species exposed to normal pH.

Results: Overall, no skeleton malformations were found in both pH conditions, but among-site differences were found in the elemental composition. Interestingly, higher Ca/P values, inducing a moderate skeleton maturation, were found in fish exposed to acidified conditions than in controls.

Conclusion: Our findings suggest that ocean acidification may play a significant role in physiological processes related to mineralization, fostering skeleton pre-aging.

Keywords: Gobius bucchichi; Infrared spectroscopy; Metals bioaccumulation; Ocean acidification; Skeletal composition; Skeletal structure.