A new drop net is described which samples a column of water from surface to bottom. The net is non-sprung and falls freely to bottom. Surface pontoons release the net as a ring covering 182 m2; the net assumes a cylinder shape closed at the top, and then strains the water column as it descends. On bottom, the net is pursed and retrieved. A parachute effect combined with vertical vectors of downward force keeps the net at full aperture. Field tests with 1.0-m and 15.2-m diameter models in depths to 28 m were made in Green Bay, Lake Michigan. Details of net construction and the delivery device employed are provided.
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