THREE NEW ZOOPLANKTON NETS DESIGNED FOR UNDER-ICE SAMPLING; WITH PRELIMINARY RESULTS OF COLLECTIONS MADE FROM ELLIS FJORD,

Abstract: Three new zooplankton nets have been designed to enable improved collection of zooplankters from ice-covered waters. These nets also enable quanti-tative sampling of species not adequately sampled by other methods. The first net is a vertical tow net which can be folded like an umbrella to pass through a small ice hole (10 cm). This 'Umbrella Net ' takes an integrated sample of zoo-plankton from all sample depths. The second net is a collapsible free-fall net designed to collect mobile zooplankters capable of avoiding towed nets. This was the only net used which was capable of collecting all furcilia stages of Euphausia crystallorophias from Ellis Fjord, Vestfold Hills, Antarctica. The third net is a diver-operated push net designed to collect zooplankters in the top 15 cm of the under-ice water column. Because of the high standing crop of phytoplankton at and near the under-ice surface at particular times of the year, some species of zooplankton tend to congregate there. These species, particularly Paralabidocera antarctica, were collected in great abundance using the push net, but were rare in samples collected by other methods. 1