Elevated p CO2 does not impair performance in autotomised individuals of the intertidal predatory starfish Asterias rubens (Linnaeus, 1758)

• Published in: Marine Environmental Research
• Main Authors: McCarthy, Ian, Whiteley, Nia, Fernandez, Wellington, Ragagnin, Marilia, Cornwell, Tomas, Suckling, Coleen, Turra, Alexander
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2020
• Subjects: Global change; Water chemistry; Ocean Acidification; Asteroidea; growth; regeneration; Righting Time Response; Ocean acidification
• Online Access: https://research.bangor.ac.uk/portal/en/researchoutputs/elevated-pco2-does-not-impair-performance-in-autotomised-individuals-of-the-intertidal-predatory-starfish-asterias-rubens-linnaeus-1758(3ec4e8bd-7d9b-479b-8fb6-52cf7022e8a3).html; https://doi.org/10.1016/j.marenvres.2019.104841; https://research.bangor.ac.uk/ws/files/26535666/2019_Elevated_pCO2_does_not_impair_performance_in_automised_individuals.pdf

The impacts of ocean acidification remain less well-studied in starfish compared to other echinoderm groups. This study examined the combined effects of elevated p CO2 and arm regeneration on the performance of the intertidal predatory starfish Asterias rubens , as both are predicted to come at a cost to the individual. A two-way factorial experiment (~400 µatm vs ~1000 µatm; autotomised vs non-automised individuals) was used to examine growth rates, lipid content (pyloric caeca and gonads), and calcium content (body wall) in both intact and regenerating arms, as well as subsequent effects on rate of arm regeneration, righting time (behaviour) and mortality over 120 days. Autotomised individuals tended to show lower (not significant), survival and growth. Elevated p CO2 had no effect on mortality, body growth, arm regeneration, righting time or arm calcium content. Lipid content was higher in the pyloric caeca, but not in the gonads, in response to elevated p CO2 irrespective of autotomisation. The results of the study suggest that adult A. rubens remain unaffected by increased p CO2 and/or arm autotomy for 120 days, although longer term experiments are necessary as the results indicated that survival, growth and calcification may be impaired with longer-term exposure to elevated p CO2.