1. Larval Pacific Oyster (Crassostreagigas)Response to Ocean Acidification Emma Timmins-Schiffman, Steven Roberts, Paul McElhany, Shallin Busch University of Washington, School of Aquatic and Fishery Sciences SICB, January 7, 2011
2. Objective How do human impacts, such as ocean acidification, affect oyster larvae?
3. Outline Background on ocean acidification Oyster development Ocean acidification effects on different stages of larval development Conclusion
4. Ocean Acidification 1000 ppm Increased CO2 in atmosphere 380 ppm Increased oceanic CO2 = lower oceanic pH
5. Timeline of C. gigas Larval Development Fertilization 2-cell Developmental Stage 0h 4-cell 1h hatching 2h pre-veliger 5h veliger Time Post-Fertilization 17h 24h
9. Timing of Development Developmental lag under OA conditions Or larvae are not developing at all Proportion Eggs in Cleavage Settlement Resource availability Optimal environmental conditions
15. Larval Gene Expression: Sptlc1 OA is altering phenotype and affecting gene expression Pathway important in normal development? Relative Expression Level
16. Conclusions Ocean acidification has significant effects on C. gigas larval development and physiology More abnormal morphology Less calcification Changes in stress-related genes
17. Conclusions Adaptation to 380 ppm CO2 may not hold true for projected greater rate of change 100 years 600 ppm 250 years, 100 ppm