Standard Presentation (15 mins) Australian Marine Sciences Association 2022

Synergistic effect of increasing temperature and CO2 on hatching success of Antarctic krill embryos (#223)

So Kawaguchi 1 , Rob King 1 , Simon Wotherspoon 1 , Andrew Lenton 2 , Martin Cox 1 , Ashley Cooper 1 , Blair Smith 1 , Tasha Waller 1 , Mel Evans 1 , Dale Maschette 1 3 , Jessica Melvin 3 , Andrew Constable 1 3
  1. Australian Antarctic Division, Kingston, TAS, Australia
  2. CSIRO Oceans and Atmosphere, Hobart, TAS, Australia
  3. Institute for Marine & Antarctic Studies, University of Tasmania, Hobart, TAS, Australia

The Southern Ocean ecosystem is facing challenges as ocean temperature continues to rise and carbon dioxide level increases. Antarctic krill is a key species of the Southern Ocean ecosystem playing a crucial role in the structure and functioning of the regional marine ecosystem. Understanding how krill will fare in the changing environment is vital for the planning and development of conservation strategies for the Southern Ocean ecosystems. We, for the first time, conducted laboratory experiments to evaluate how the combined effects of increasing temperature and pCO2 may affect the hatching success of krill embryos. Our results showed temperature is likely to have a major effect on hatching success. Furthermore, we found increasing pCO2 narrowed in the temperature range for successful hatching of krill embryos. We discuss how future increases in temperature and pCO2 may lead to regional differences in the rates of krill embryo hatching success.