Among the grazers the salp (primarily Salpa thompsoni), which is a free-floating tunicate, is very abundant. To a certain degree their distribution overlaps with that of Antarctic krill, but the salps tend to occupy lower-production regions and tolerate warmer waters than the Antarctic krill.
The large order of Amphipods can be benthic or pelagic, parasitic or free-living depending on species. Of the pelagic species in the Souther Ocean, Themisto gaudichaudii is the most abundant. It is likely the most abundant pelagic crustacean in the Southern ocean after copepods, krill and salps, which are all mainly planktivorous. T. gaudichaudi is carnivorous and may in some Antarctic regions be observed in dense swarms, for instance around South Georgia. It is an important food source for many top predators including species of penguins, flying birds, whales, fish and squid.