Larval & Post-Larval Responses of Pacific Oysters to Elevated CO2
Ginger, K.W.K., Vera, C.B.S., Dineshram, R., Dennis, C.K.S., Adela, L.J., Yu, Z. and Thiyagarajan, V. 2013. Larval and post-larval stages of Pacific oyster (Crassostrea gigas) are resistant to elevated CO2. PLoS ONE 8: e64147.
Against this backdrop, and based on multiple physiological measurements made during various life stages of the oysters, Ginger et al. studied "the effects of long-term (40 days) exposure to pH 8.1, 7.7 and 7.4 on larval shell growth, metamorphosis, respiration and filtration rates at the time of metamorphosis, as well as the juvenile shell growth and structure of C. gigas. In doing so the seven scientists discovered that (1) "mean survival and growth rates were not affected by pH," that (2) "the metabolic, feeding and metamorphosis rates of pediveliger larvae were similar, between pH 8.1 and 7.7," that (3) "the pediveligers at pH 7.4 showed reduced weight-specific metabolic and filtration rates, yet were able to sustain a more rapid post-settlement growth rate," and that (4) "no evidence suggested that low pH treatments resulted in alterations to the shell ultra-structures or elemental compositions (i.e., Mg/Ca and Sr/Ca ratios)."
In light of these several positive findings, Ginger et al. concluded that "larval and post-larval forms of the C. gigas in the Yellow Sea are probably resistant to elevated CO2 and decreased near-future pH scenarios." In fact, they opine that "the pre-adapted ability to resist a wide range of decreased pH may provide C. gigas with the necessary tolerance to withstand rapid pH changes over the coming century."