Publication Date:
2024-03-15
Description:
Among bivalves, scallops are exceptional due to their capacity to escape from predators by swimming which is provided by rapid and strong claps that are produced by the phasic muscle interspersed with tonic muscle contractions. Based on the concept of oxygen and capacity-limited thermal tolerance, the following hypothesis was tested: ocean warming and acidification (OWA) would induce disturbances in aerobic metabolic scope and extracellular acid-case status and impair swimming performance in temperate scallops. Following long-term incubation under near-future OWA scenarios [20 vs. 10 °C (control) and 0.112 kPa CO2 (hypercapnia) vs. 0.040 kPa CO2 (normocapnic control)], the clapping performance and metabolic rates (MR) were measured in resting (RMR) and fatigued (maximum MR) king scallops, Pecten maximus, from Roscoff, France. Exposure to OA, either alone or combined with warming, left MR and swimming parameters such as the total number of claps and clapping forces virtually unchanged. Only the duration of the escape response was affected by OA which caused earlier exhaustion in hyper- than in normocapnic scallops at 10 °C. While maximum MR was unaffected, warm exposure increased RMR in both normocapnic and hypercapnic P. maximus resulting in similar Q 10 values of ~2.2. The increased costs of maintenance and the observation of strongly reduced haemolymph PO2 levels indicate that at 20 °C scallops have reached the upper thermal pejus range with unbalanced capacities for aerobic energy metabolism. As a consequence, warming to 20 °C decreased mean phasic force during escape performance until fatigue. The observed prolonged recovery time in warm incubated scallops might be a consequence of elevated metabolic costs at reduced oxygen availability in the warmth.
Keywords:
Acid-base regulation; Alkalinity, total; Animalia; Aragonite saturation state; Behaviour; Benthic animals; Benthos; Bicarbonate ion; Bottles or small containers/Aquaria (〈20 L); Calcite saturation state; Calculated; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Coast and continental shelf; Condition index; Coulometric titration; Dry mass; EXP; Experiment; Factorial aerobic scope; Force; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Haemolymph, bicarbonate ion; Haemolymph, partial pressure of carbon dioxide; Haemolymph, partial pressure of oxygen; Haemolymph, pH; Haemolymph, total carbon dioxide; Height; Identification; Laboratory experiment; Length; Metabolic rate of oxygen; Mollusca; Muscle condition index; Net aerobic scope; North Atlantic; Number of claps; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide, standard deviation; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pecten maximus; pH; pH, standard deviation; Potentiometric; Respiration; Roscoff_OA; Salinity; Salinity, standard deviation; Single species; Species; Temperate; Temperature; Temperature, water; Temperature, water, standard deviation; Time in hours; Time in minutes; Treatment; Width
Type:
Dataset
Format:
text/tab-separated-values, 3046 data points
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