Table 3.

Information contained in the post-processed dataset.

Variable	Description
Time	Minute timestamp of the measurement.
Density (Sv)	Measure for total fish biomass in the water column.
Abundance (Sa)	Measure for the abundance of fish scatterers.
Centre of mass (CM)	Mean range of fish from the transducer.
Proportion occupied (Pocc)	Proportion of cells in the water column that contain fish.
Inertia (I)	Dispersion (or spread) of fish in the water column.
Evenness (EA)	Area occupied if all samples contained the mean fish density.
Index for aggregation (IA)	Measure for the compactness of fish in smaller areas (vs. being evenly distributed in the water column).
Diel stage	Indicates if measurement was taken at night or at day. 1 indicates times after sunrise (e.g. day) and 0 times after sunset (e.g. night).
CSPD	Current speed.
Shear	The absolute mean difference in vertical velocity between the upper and lower layers.
Temperature	Temperature measurement at mooring depth.
Tidal stage	Indicates if measurement was taken during ebb when tidal currents flowed eastward towards the Tasman sea or during flood tide when tidal currents flowed westwards into the Banks Strait. 0 indicates ebb and 1 flood.