Ocean acidification research on crabs and coccolithophores

PI: Jonathan Stillman


Research Institution:          San Francisco State University

PI First name, Last name:  Dr. Jonathan Stillman

Phone:                              415-338-3790

Email:                               stillmaj@sfsu.edu

Project website link (if available):  http://online.sfsu.edu/~stillmaj



The Stillman laboratory is presently engaged in three research projects involving ocean acidification, two on crabs and one on coccolithophores.   The first crab project, on intertidal zone porcelain crabs, is supported by NSF and involves 2 aims: (1) an analysis of how OA impacts the physiology of early life history stages (embryos, larvae, recruits) and (2) synergistic effects of acidification and thermal stress in adults.   The first aim involves acclimation of crab early life history stages in water with differing pCO2 and measurement of response variables including growth rate, respiration rate, heart rate, morphology, lipid and protein content (C/N), lipid consumption rate, and molecular phenotypes at the transcriptome and proteome level.   The second aim involves acclimation to differing thermal and pCO2 variability followed by measurement of metabolic rate, cardiac rate, cardiac CTmax, and molecular phenotypes, as above.  The second crab project, a contract with the NOAA aquaculture facility in Kodiak Alaska involves examination of genomic variation in red king crab early life history stages following acclimation to differently acidified waters.  The coccolithophore project, a collaboration with Co-PIs Ed Carpenter and Tomoko Komada and postdoctoral fellows Stephane Lefebvre and Ina Benner, involves an examination of multi-factor long term acclimation responses of Emiliania huxleyi grown in continuous culture for many hundreds of generations.  In this NSF funded project we have investigated the impacts of combined effects of varying pCO2 and nitrogen source (NO3 vs. NH4), and the combined effects of varying pCO2 and temperature on the physiology of the coccolithophorids.  Response variables include growth rate, cell size, cell morphology, PIC and POC, N assimilation rates, and molecular phenotypes at the transcriptomic, proteomic and metabolomic levels.  Our first paper, showing that N source plays a larger role in regulation of calcification rate than does pH, has just been published inGlobal Change Biology (Lefebvre et al., 2011).

KEYWORDS: intertidal zone, crabs, coccolithophores, nitrogen, temperature, synergistic effects, genomics