Salp metabolism: temperature and oxygen partial pressure effect on the physiology of Salpa fusiformis from the California Current

Abstract

Abstract Salps are pelagic tunicates that play an important role in carbon cycling by filter feeding and packaging waste into dense fecal pellets that sink rapidly to the deep ocean. There has been limited research on salp physiology and no studies that examine how changes in environmental factors such as temperature and dissolved oxygen impact basic physiological processes. Here I examine temperature and oxygen partial pressure effect on metabolism in blastozooids of Salpa fusiformis. Routine metabolic rates of 1.66 and 3.95 μmol O2 g−1 h−1 wet weight at 10°C and 17°C, respectively, resulted in a Q10 = 3.45. The observed decrease in metabolism associated with decreased temperature, as well as hypoxia tolerance, is explored in the context of observed vertical migrations into hypoxic waters in the California Current, and potential impacts on carbon output. Metabolic rates for S. fusiformis are compared to metabolic rates published for other species of salps and gelatinous zooplankton. Expansion of this work across a broader set of species is critical to quantify the impact climate change may have on salps and their role in marine carbon cycling.