Long-term and trans-life-cycle effects of exposure to ocean acidification in the green sea urchin Strongylocentrotus droebachiensis

Abstract

Anthropogenic CO 2 emissions are acidifying the world's oceans. A growing body of evidence demonstrates that ocean acidification can impact survival, growth, development and physiology of marine invertebrates. Here, we tested the impact of long-term (up to 16 months) and trans-life-cycle (adult, embryo/larvae and juvenile) exposure to elevated pCO 2 (1,200 latm, compared to control 400 latm) on the green sea urchin Strongylocentrotus droebachiensis. Female fecundity was decreased 4.5-fold when acclimated to elevated pCO 2 for 4 months during reproductive conditioning, while no difference was observed in females acclimated for 16 months. Moreover, adult pre-exposure for 4 months to elevated pCO 2 had a direct negative impact on subsequent larval settlement success. Five to nine times fewer offspring reached the juvenile stage in cultures using gametes collected from adults previously acclimated to high pCO 2 for 4 months. However, no difference in larval survival was observed when adults were pre-exposed for 16 months to elevated pCO 2 . pCO 2 had no direct negative impact on juvenile survival except when both larvae and juveniles were raised in elevated pCO 2 . These negative effects on settlement success and juvenile survival can be attributed to carryover effects from adults to larvae and from larvae to juveniles. Our results support the contention that adult sea urchins can acclimate to moderately elevated pCO 2 in a matter of a few months and that carry-over effects can exacerbate the negative impact of ocean acidification on larvae and juveniles.

Long-term exposure to elevated pCO2 more than warming modifies early-life shell growth in a temperate gastropod

“…Bark-like crystal shapes such as the ones found in the acidified samples in this study seem to be a phenomenon not yet widely described in the literature. Seeing as the current literature is still dominated by short-term single stressors studies of adult specimens, our results highlight the need to investigate the development of shell mineralogy and ultrastructure in juvenile molluscs under high temperature and CO 2 environments, over extended time periods, and considering the cumulative effects of exposure (such as here and in Dupont et al, 2013). Adult individuals transplanted into conditions of elevated pCO 2 exhibit distinctly different calcification patterns in localized, newly built shell areas, including Long-term exposure to elevated pCO 2 unorganized crystals with varying growth directions (Hahn et al, 2011).…”

Tolerance of Hyas araneus zoea I larvae to elevated seawater PCO2 despite elevated metabolic costs

“…It seems that the zoea I stage of H. araneus is able to compensate for the elevated costs associated with the development in a high PCO 2 environment. However, as it has been found by Dupont et al (2012) this compensation might be an energy consuming process and might therefore affect performance of later stages by carry-over effects due to depletion of energy reserves.…”

Ocean acidification and temperature rise: effects on calcification during early development of the cuttlefish Sepia officinalis

“…The effect of raised pCO 2 should be investigated on the animal entire life cycle considering possible carry-over effects (e.g. Parker et al 2012, Dupont et al 2012 and not only from the calcification point of view. Linked to buoyancy abilities, further studies on feeding behavior under projected scenarios of future environmental change would be required in order to assess CO 2 impacts on population dynamics of the cuttlefish S. officinalis.…”

“…Additionally, very few studies have considered the impacts of global change on several successive life-stages (e.g. Parker et al 2012, Dupont et al 2012, while the transition from one stage to another (e.g. metamorphosis, hatching) can be radical.…”