The feeding rates of the pelagic tunicate Pegea confederata and two other salps1

The filtration rates of Pegea confederata, Salpa maxima, and Cyclosalpa a;ffinis were measured. Filtration rates increase exponentially with increasing length and body carbon. Filtration rates exceeding 100 ml min-’ were recorded. The mucous net of P. confederata can retain particles at least as small as 0.7 P. There appears to be no change in filtration rate with changes in particle concentration. Filtration rate per microgram of carbon increases with increasing body weight of salps in contrast to ascidians, perhaps because salps use muscular pumping rather than ciliary currents to transport water. The filtration rates recorded suggest that the role of salps in the open ocean ecosystem may be more important than previously assumed.