Ocean acidification impairs vermetid reef recruitment

Area of Science:

• Marine Biology
• Ecology
• Climate Change Science

Background:

• Vermetid gastropods construct vital reefs in subtropical and warm-temperate zones, offering coastal protection, sediment regulation, carbon sequestration, and habitat provision.
• These reef-building species brood encapsulated larvae and possess limited dispersal capabilities, making them vulnerable to environmental shifts.

Purpose of the Study:

• To evaluate the impact of ocean acidification on the reef-building gastropod Dendropoma petraeum using transplant experiments along a natural CO2 gradient.
• To assess the effects of predicted future acidified conditions on the reproduction, recruitment, and shell integrity of D. petraeum.

Main Methods:

• Conducted transplant experiments with Dendropoma petraeum along a natural gradient of varying carbon dioxide (CO2) levels.
• Monitored reproductive success, larval brooding, recruitment rates, and analyzed shell composition (including Mg content) and dissolution under different CO2 exposures.

Main Results:

• Dendropoma petraeum demonstrated the capacity for reproduction and brooding even under elevated CO2 conditions.
• Recruitment success was significantly reduced under higher CO2 levels, indicating impaired larval settlement or survival.
• Long-term exposure to acidified conditions led to shell dissolution and a notable increase in shell magnesium content.

Conclusions:

• Ocean acidification poses a severe threat to Dendropoma petraeum populations and the integrity of the reefs they build.
• Urgent reductions in CO2 emissions and conservation strategies are necessary to prevent the potential extinction of these reefs and mitigate ecological and socioeconomic consequences.