to investigate the distributional movement patterns of the Maui's dolphin (Cephalorhynchus hectori maui) within the Manukau Harbour region, New Zealand. Porpoise detection devices (PODs), which are self-contained submersible computers and hydrophone loggers that recognise and log echolocation ultrasound clicks of dolphins, were used. 'Acoustic fences' could be established across the width of the harbour entrance, using PODs to analyse time-specific data on direction of movement and time spent

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... side the harbour by Maui's dolphins. The pilot study was focused on calibrating the PODs and determining the feasibility of using them. Controlled POD tests were on recorded Hector's dolphin sounds over two days and again in different waterbodies within the Manukau Harbour. POD tests for dolphins actually sighted outside of the Manukau Harbour region were also done over a two-day period. Physical constraints important in planned moorings and placement of PODs across the harbour channel mouth were also reviewed. Actual and potential problems with the technique were discussed. Firm conclusions could not be drawn because of the lack of encounters with dolphins during the feasibility trials. .