Meeting Abstract
Salps are pelagic tunicates that are found throughout the world’s oceans and marginal seas. They play an important role in carbon and food importation into the deep sea as a result of their relatively large, dense, fecal pellets that sink quite rapidly and reach the bathypelagic intact. There is limited understanding of salp physiology, and how it is impacted by environmental changes. Here, I present data from Salpa fusiformis, a cosmopolitan species that is known to vertically migrate, and experiences a range of environmental temperatures and oxygen partial pressures. Temperature had a significant effect on routine metabolic rate with mean MO2 =3.95 ± 0.53 µmol O2 g-1 h-1 at 17ºC (n=18), and 1.65 ± 0.17 µmol O2 g-1 h-1 at 10ºC (n=15) (ANCOVA, p<0.0001) resulting in a Q10 temperature coefficient of 3.48. Additionally temperature appeared to have an effect on critical partial pressure with Pcrit = 3.4 kPa at 17ºC (n=2) and 1.9 kPa at 10ºC (n=1). Individual zooids were able to consume oxygen below detectable levels in respirometery chambers and recover when reoxygenated at both 17ºC and 10ºC. The observed temperature effect on metabolism and apparent hypoxia tolerance would assist S. fusiformis in diurnal vertical migrations in areas with pronounced oxygen minimum zones. Expansion of this work across a broader set of species will help elucidate the impact salps have in carbon cycling in the world’s oceans and the influence climate change could have on salp mediated carbon cycling to the deep sea.
