Macrozooplankton taxonomic density collected using a 1 x 1 m square net with 700-μm mesh at Palmer Station, Antarctica during Palmer LTER field seasons, 2017-2020

Zooplankton are a morphologically and taxonomically diverse group of animals. Many zooplankton feed on phytoplankton in surface waters and thus provide a link between primary producers and higher trophic levels. The numerical density of common macrozooplankton taxa was determined at Palmer LTER Stations B and E. Samples were collected with a 1 x 1 m square, 700-μm mesh Metro net towed obliquely from the surface to a target depth of 50 m and back. Duplicate tows typically were conducted at each sampling site. Tows were conducted during daytime, and sampling frequency was nominally twice weekly while personnel were at Palmer Station between the months of November and March. The catch was sorted and counted live. Data are provided for the following taxa, which dominated biomass: the euphausiids Euphausia superba and Thysanoessa macrura, the thecosome pteropod Limacina rangii, gymnosome pteropods, the salp Salpa thompsoni, amphipods, and larval fishes. Density varies across taxa, seasonally, among years, and between sampling stations. Units of density are individuals per cubic meter.