Warming and pCO2 effects on Florida stone crab larvae

Greenhouse gas emissions are increasing ocean temperatures and the partial pressure of CO2 (pCO(2)), resulting in more acidic waters. It is presently unknown how elevated temperature and pCO(2) will influence the early life history stages of the majority of marine coastal species. We investigated the combined effect of elevated temperature (30 degrees C control and 32 degrees C treatment) and elevated pCO(2) (450 rho atm control and 1100 mu atm treatment) on the (i) growth, (ii) survival, (iii) condition, and (iv) morphology of larvae of the commercially important Florida stone crab, Menippe mercenaria. At elevated temperature, larvae exhibited a significantly shorter molt stage, and elevated pCO2 caused stage-V larvae to delay metamorphosis to post-larvae, On average, elevated pCO(2) resulted in a 37% decrease in survivorship relative to the control; however the effect of elevated temperature reduced larval survivorship by 71%. Exposure to both elevated temperature and pCO(2) reduced larval survivorship by 80% relative to the control. Despite this, no significant differences were detected in the condition or morphology of stone crab larvae when subjected to elevated temperature and pCO(2) treatments. Although elevated pCO(2) could result in a reduction in larval supply, future increases in seawater temperatures are even more likely to threaten the future sustainability of the stone-crab fishery. (C) 2018 Elsevier Ltd. All rights reserved.