Oxygen uptake and haemolymph oxygen tension in the stalked barnacleCalantica spinosa

Abstract

Abstract Oxygen uptake (VO2) and haemolymph oxygen tension (PO2) were determined for the intertidal, stalked barnacle Calantica spinosa (Quoy & Gaimard) during submersion and aerial exposure at 15°C. VO2 did not change significantly with emersion, but peduncular sinus haemolymph PO2 increased significantly after 1–2 h in air. The maintenance of aerobic metabolism during aerial exposure described for C. spinosa contrasts with the depressed VO2 generally reported for intertidal filter-feeding invertebrates on emersion. The increased haemolymph PO2 reported for stalked barnacles in air (characteristic of terrestrial, air-breathing decapod crustaceans) is in contrast to the respiratory pattern displayed by other aquatic invertebrates during aerial exposure. The respiratory physiology of C. spinosa in aquatic and aerial environments is discussed with particular reference to its feeding behaviour.