Elemental composition, respiration, and excretion measurements of pteropods collected from the PAL LTER research cruises along the Western Antarctic Peninsula 2017-2019.

• Main Authors: LTER, Palmer Station Antarctica, Thibodeau, Patricia
• Format: Dataset
• Language: English
• Published: Environmental Data Initiative 2020
• Subjects: Antarctic; Antarctic Peninsula; Southern Ocean; Antarc*; Antarctica; Limacina helicina
• Online Access: https://dx.doi.org/10.6073/pasta/d5802e3bdd745dbdd10d2f7bf998027b; https://portal.edirepository.org/nis/mapbrowse?packageid=knb-lter-pal.304.3

Pteropods (pelagic snails) are abundant zooplankton in the Southern Ocean where they are important grazers of phytoplankton, prey for higher trophic levels, and sensitive to environmental change. In this study, the effects of warming seawater temperatures and shifting food availability on Limacina helicina antarctica metabolism (respiration and excretion) were determined by conducting shipboard experiments that exposed pteropods to a range of temperatures and phytoplankton (food) concentrations. Pteropods and all other macrozooplankton were collected with a 2 m square frame Metro net (700 µm mesh), towed obliquely to depths up to 120 m (Ross et al., 2008; Steinberg et al., 2015), or with shallower (0-50 m), vertical tows if pteropods were very abundant. Pteropods were exposed to varying temperature and food conditions for 12 hours and respiration and excretion were measured. Incubations were also conducted with non-shelled pteropod species and shelled pteropod, Clio pyramidata, measuring pteropod respiration under in situ conditions. Finally, a CO2 perturbation experiment measuring L. h. antarctica metabolism (respiration and excretion) under pre-industrial and elevated dissolved CO2 conditions at ambient temperature in filtered seawater (no food), during the 2018 PAL LTER research cruise. Results reveal the metabolic response of pteropods to ocean variability, increase our understanding of the role of zooplankton in biogeochemical cycles, and help predict future responses to climate change.