|Amy E. Maas, Leanne E. Elder, Heidi M. Dierssen, and Brad A. Seibel, |
Metabolic response of Antarctic pteropods (Mollusca: Gastropoda) to food deprivation and regional productivity:, Marine Ecology Progress Series, 2011
Pteropods are an abundant group of pelagic mollusks that, although temporally and spatially patchy in the Southern Ocean, can play an important role in food webs and biochemical cycles. We find that the metabolic rate in Limacina helicina antarctica is depressed (~23%) at lower mean chlorophyll a concentrations in the Ross Sea. To assess the specific impact of food deprivation on these animals, we quantify aerobic respiration and ammonia (NH3) production for two dominant Antarctic pteropods, Limacina helicina antarctica and Clione limacina antarctica. Pteropods collected from sites around Ross Island, Antarctica were held in captivity for a period of 1-13 days to determine their metabolic response to laboratory induced food deprivation. Limacina helicina antarctica reduced oxygen consumption by ~20% after 4 days in captivity. Ammonia excretion was not significantly affected, suggesting a greater reliance on protein as substrate for cellular respiration during starvation. The oxygen consumption rate of the gymnosome, Clione limacina antarctica, was reduced by ~ 35% and NH3 excretion by ~55% after 4 days without prey. Our results indicate that there is a link between the large scale chlorophyll a concentrations of the Ross Sea and the baseline metabolic rate of pteropods which impacts these animals across multiple seasons.