MEPS 637:87-101 (2020) - DOI: https://doi.org/10.3354/meps13236
Key biological responses over two generations of the sea urchin Echinometra sp. A under future ocean conditions
S. Uthicke1,*, F. Patel1, S. Karelitz2, H. M. Luter1, N. S. Webster1,3, M. Lamare2
ABSTRACT: Few studies have investigated the effects of ocean warming and acidification on marine benthic organisms over ecologically relevant time scales. We used an environmentally controlled coral reef mesocosm system to assess growth and physiological responses of the sea urchin species Echinometra sp. A over 2 generations. Each mesocosm was controlled for temperature and pCO2 over 29 mo under 3 climate change scenarios (present day and predicted states in 2050 and 2100 under RCP 8.5). The system maintained treatment conditions including annual temperature cycles and a daily variation in pCO2. Over 20 mo, adult Echinometra exhibited no significant difference in size and weight among the treatments. Growth rates and respiration rates did not differ significantly among treatments. Urchins from the 2100 treatment had elevated ammonium excretion rates and reduced O2:N ratios, suggesting a change in catabolism. We detected no difference in spawning index scores or oocyte size after 20 mo in the treatments, suggesting that gonad development was not impaired by variations in pCO2 and temperature reflecting anticipated climate change scenarios. Larvae produced from experimentally exposed adults were successfully settled from all treatments and raised for 5 mo inside the mesocosm. The final size of these juveniles exhibited no significant difference among treatments. Overall, we demonstrated that the mesocosm system provided a near natural environment for this urchin species. Climate change and ocean acidification did not affect the benthic life stages investigated here. Importantly, in previous short-term (weeks to months) experiments, this species exhibited reductions in growth and gonad development, highlighting the potential for short-term experiments with non-acclimated animals to yield contrasting, possibly erroneous results.
KEY WORDS: Ocean acidification · Ocean warming · Climate scenarios · Calcifying invertebrates
Full text in pdf format  Supplementary material | Cite this article as: Uthicke S, Patel F, Karelitz S, Luter HM, Webster NS, Lamare M
(2020) Key biological responses over two generations of the sea urchin Echinometra sp. A under future ocean conditions. Mar Ecol Prog Ser 637:87-101. https://doi.org/10.3354/meps13236
Export citation Share: Facebook - - linkedIn |
| Previous article Next article |