Sharks have been facing unprecedented pressure over the last decades, and ocean acidification may represent an additional threat, particularly during their most susceptible life stages. Hence, the present study aimed to investigate the effects of ocean acidification (control pCO 2 ~ 400 μatm; high pCO 2 ~ 900 μatm) on the growth, swimming performance and cholinergic system of juvenile white-spotted bamboo sharks (Chiloscyllium plagiosum). After 45 days of exposure, we observed that high CO 2 did not affect most of the end-points studied. However, somatic growth rate and the percentage of time that sharks spent swimming was significantly reduced under high CO 2 conditions. Moreover, AChE activity decreased in two of the seven brain macroareas analyzed, the telencephalon and optic lobes. As this near-threatened shark species showed small sub-lethal effects to high CO 2 levels, we argue that within a longer time-frame they can potentially reduce individual performance with cascading consequences to shark population dynamics.
- climate change