Elevated pCO2 increases sperm limitation and risk of polyspermy in the red sea urchin Strongylocentrotus franciscanus

Visconti

Marine Environmental Research

et al. 2014

a b s t r a c tThe increasing abundances of the thermophilous black sea urchin Arbacia lixula in the Mediterranean Sea are attributed to the Western Mediterranean warming. However, few data are available on the potential impact of this warming on A. lixula in combination with other global stressors such as ocean acidification. The aim of this study is to investigate the interactive effects of increased temperature and of decreased pH on fertilization and early development of A. lixula. This was tested using a fully crossed design with four temperatures (20, 24, 26 and 27 C) and two pH levels (pH NBS 8.2 and 7.9). Temperature and pH had no significant effect on fertilization and larval survival (2d) for temperature <27 C. At 27 C, the fertilization success was very low (<1%) and all larvae died within 2d. Both temperature and pH had effects on the developmental dynamics. Temperature appeared to modulate the impact of decreasing pH on the % of larvae reaching the pluteus stage leading to a positive effect (faster growth compared to pH 8.2) of low pH at 20 C, a neutral effect at 24 C and a negative effect (slower growth) at 26 C. These results highlight the importance of considering a range of temperatures covering today and the future environmental variability in any experiment aiming at studying the impact of ocean acidification.

Section: Impact Of Ph and Temperature On Developmental Ratesupporting

confidence: 92%

Section: Impact Of Ph and Temperature On Developmental Ratementioning

confidence: 99%

Temperature modulates the response of the thermophilous sea urchin Arbacia lixula early life stages to CO2-driven acidification

Visconti

Marine Environmental Research

et al. 2014

“…Although elevated CO 2 was not found to reduce fertilisation, nor temperature to enhance fertilisation in a range of echinoderms including once again the echinoid, Heliocidaris erythrogramma and the closely related species, Heliocidaris tuberculata, Tripneustes gratilla, Centrostephanus rodgersii and the asteroid, Patiriella regularis from a range of regions along the east coast of Australia ranging from (42°50'S, 147°15'E) to (30°12'S, 153°16'E) [48]. Nor was there a synergistic interaction between elevated CO 2 and temperature and no trend for reduced fertilisation with increased concentration of CO 2 over a range of sperm concentrations [47,54,55] Sperm concentration appears to be a significant factor for organisms when other conditions are suboptimal. Ericson et al [54] found no effect on fertilisation of elevated CO 2 and decreased pH at levels predicted for the year 2100, for the echinoid, Sterechinus neumayeri, but did find an effect of elevated CO 2 when sperm concentration was suboptimal.…”

Section: Fertilisationmentioning

confidence: 99%

“…Across a broad range of broadcast spawners with planktotrophic larvae dependent on an exogenous food supply, it is thought that fertilisation compared to larval development is relatively robust to ocean acidification and decreased pH at levels predicted for the year 2100 ( [14]; echinoderms [34,47,48]; molluscs [49]; copepod Acartia tsuensis, [50]; fish Baltic cod, Gadhus morhua, [51]), but may be negatively impacted at pH levels predicted for 2300 ( [1,52,53] [47,54,55] (Table S2).…”

Section: Fertilisationmentioning

confidence: 99%

“…Such contrasting results, even for identical species, could be due to differences in experimental methodology arising from single male and female crosses in Havenhand et al [56] versus multiple males and females in Byrne et al [34,47,48] and high fertilisation success in controls [56] 62% versus [47,48] 80-90%). It remains unclear whether intra and inter specific differences are real or due to differences in experimental techniques [47,54,55] by the pooling of gametes from males and females [34,47,48], creating arguments about polyandry versus single crosses and their influence on results and interpretation and or misinterpretations and measurement in fertilisation due to polyspermy. Whether polyandry or single crosses, even recent studies are based on small sample sizes of males and females ([34] 2 males: 2 females; [47] 3 males: 3 females; [54], 1 male: 1 female) and additionally may suffer from pseudoreplication where containers are not factored as a source of variation in the analysis.…”

Section: Fertilisationmentioning

confidence: 99%

See 1 more Smart Citation

The Impact of Ocean Acidification on Reproduction, Early Development and Settlement of Marine Organisms

Ross

Parker

O’Connor³

et al. 2011

Water

144

112

Predicting the impact of warming and acidifying on oceans on the early development life history stages of invertebrates although difficult, is essential in order to anticipate the severity and consequences of future climate change. This review summarises the current literature and meta-analyses on the early life-history stages of invertebrates including fertilisation, larval development and the implications for dispersal and settlement of populations. Although fertilisation appears robust to near future predictions of ocean acidification, larval development is much more vulnerable and across invertebrate groups, evidence indicates that the impacts may be severe. This is especially for those many marine organisms which start to calcify in their larval and/or juvenile stages. Species-specificity and variability in responses and current gaps in the literature are highlighted, including the need for studies to investigate the total effects of climate change including the synergistic impact of temperature, and the need for long-term multigenerational experiments to determine whether vulnerable invertebrate species have the capacity to adapt to elevations in atmospheric CO 2 over the next century.

Sensitivity of sea urchin fertilization to pH varies across a natural pH mosaic

Kapsenberg

Okamoto

Dutton

et al. 2017

Ecology and Evolution

In the coastal ocean, temporal fluctuations in pH vary dramatically across biogeographic ranges. How such spatial differences in pH variability regimes might shape ocean acidification resistance in marine species remains unknown. We assessed the pH sensitivity of the sea urchin Strongylocentrotus purpuratus in the context of ocean pH variability. Using unique male–female pairs, originating from three sites with similar mean pH but different variability and frequency of low pH (pHT ≤ 7.8) exposures, fertilization was tested across a range of pH (pHT 7.61–8.03) and sperm concentrations. High fertilization success was maintained at low pH via a slight right shift in the fertilization function across sperm concentration. This pH effect differed by site. Urchins from the site with the narrowest pH variability regime exhibited the greatest pH sensitivity. At this site, mechanistic fertilization dynamics models support a decrease in sperm–egg interaction rate with decreasing pH. The site differences in pH sensitivity build upon recent evidence of local pH adaptation in S. purpuratus and highlight the need to incorporate environmental variability in the study of global change biology.