A 1.1‐MHz acoustic array is part of a multi‐instrument experiment designed to look at the scales and causes of the patchy distribution of nearshore marine zooplankton. The transducers have narrow, dual beam patterns (0.3 and 1 from axis to −3 dB point) and will be fired with 0.1‐ms pulses. They are to be used to determine absolute target strengths and distributions of discrete copepod‐size and larger targets. Acoustic returns will also be integrated over variable ranges. The three element array is to be placed on the bottom in 70 m of water next to thermistor, current meter, and continuous fluorometer strings. Simultaneous sampling with a large volume pump will be used to identify scatterers. Patch dimensions from 10's cm to 10's km should be observable. Current and near future work consists of calibrating the transducers and determining target strength distributions of live, local plankters and plankton assemblages in the laboratory.