Ms Erin Pichler, Professor Ivan Nagelkerken1, Dr Jonathan Leung, Professor Sean Connell
1The University Of Adelaide, Adelaide, Australia
Ocean acidification is forecast to drive a decline in populations of calcifying organisms, in particular due to its negative effects on reproduction and early life stages. The evidence on which this prediction of population decline is made rests heavily on laboratory experiments, which often lack the mediating effects of ecosystem complexity in the natural world. Therefore, whether findings of declined urchin reproductive capacity in the laboratory translate to similar outcomes for urchin populations in the wild remains mostly unknown. Using natural CO2-seeps, we test the prediction that ocean acidification can drive a decline in reproductive potential whilst accounting for the concomitant global phenomena of lower densities at vents. This is important because declining density is also associated with increasing reproductive effort. We found low densities of urchins at vents have twice as much reproductive potential as equivalent densities in current-day conditions. These findings suggest that the general observation of greater reproductive potential at vents cannot be simply explained as a function of lower density alone. These findings leaves open the possibility that greater reproductive potential is a response to acidification. Importantly, this response is opposite to almost all laboratory studies which show a decrease in reproductive potential with ocean acidification. I will present evidence on why this reversal is likely to be a more realistic model.
Presentation Files – Erin Pichler
Biography:
Erin is a PhD candidate at the University of Adelaide. Her PhD research focuses on how human impacts shape coastal systems. She is investigating the effect of climate change on coastal ecology, and how to enhance restoration efforts using ecological theory.
