Linking energy budget to physiological adaptation: How a calcifying gastropod adjusts or succumbs to ocean acidification and warming

• Published in: The Science of the total environment 2020-05, Vol.715, p.136939-136939, Article 136939
• Main Authors: Leung, Jonathan Y.S., Russell, Bayden D., Connell, Sean D.
• Format: Article
• Language: English
• Subjects: Adaptation; Adaptation, Physiological; Animals; Calcification; Carbon Dioxide; Gastropod; Gastropoda; Hydrogen-Ion Concentration; Ocean acidification; Ocean warming; Oceans and Seas; Physiology; Seawater
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2020.136939

Accelerating CO2 emissions have driven physico-chemical changes in the world's oceans, such as ocean acidification and warming. How marine organisms adjust or succumb to such environmental changes may be determined by their ability to balance energy intake against expenditure (i.e. energy budget) as energy supports physiological functions, including those with adaptive value. Here, we examined whether energy budget is a driver of physiological adaptability of marine calcifiers to the near-future ocean acidification and warming; i.e. how physiological energetics (respiration rate, feeding rate, energy assimilation and energy budget) relates to adjustments in shell growth and shell properties of a calcifying gastropod (Austrocochlea concamerata). We found that ocean warming boosted the energy budget of gastropods due to increased feeding rate, resulting in faster shell growth and greater shell strength (i.e. more mechanically resilient). When combined with ocean acidification, however, the gastropods had a substantial decrease in energy budget due to reduced feeding rate and energy assimilation, leading to the reduction in shell growth and shell strength. By linking energy budget to the adjustability of shell building, we revealed that energy availability can be critical to determine the physiological adaptability of marine calcifiers to the changing oceanic climate. [Display omitted] •Energetics and shell properties of gastropods were measured under future climate.•Ocean warming increased the feeding rate and hence energy budget of gastropods.•The boosted energy budget was linked to increased shell growth and shell strength.•Ocean acidification caused these positive effects of warming to become negative.•Energy budget determined the adjustability of shell building process in calcifiers.