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GUIDELINES FOR ESTIMATING THE GREEN WEIGHT OF KRILL CAUGHT Method Equation (kg) Parameter Description Type Estimation method Unit Holding tank volume W * L * H * ρ * 1 000 W = tank width Constant Measure at the start of fishing m L = tank length Constant Measure at the start of fishing m ρ = volume-to-mass conversion factor Variable Volume-to-mass conversion kg/litre H = depth of krill in tank Haul-specific Direct observation m Flow meter V * Fkrill * ρ V = volume of krill and water combined Haul -specific Direct observation litre Fkrill = fraction of krill in the sample Haul -specific Flow meter volume correction — ρ = volume-to-mass conversion factor Variable Volume-to-mass conversion kg/litre Flow meter (V * ρ) – M V = volume of krill paste Haul -specific Direct observation litre M = amount of water added to the process, converted to mass Haul -specific Direct observation kg ρ = density of krill paste Variable Direct observation kg/litre Flow scale M * (1 – F) M = mass of krill and water combined Haul -specific Direct observation kg F = fraction of water in the sample Variable Flow scale mass correction — Plate tray (M – Mtray) * N

Mtray = mass of empty tray Constant Direct observation prior to fishing kg M = mean mass of krill and tray combined Variable Direct observation, prior to freezing with water drained kg N = number of trays Haul-specific Direct observation — Meal conversion Mmeal * MCF Mmeal = mass of meal produced Haul-specific Direct observation kg MCF = meal conversion factor Variable Meal to whole krill conversion — Codend volume W * H * L * ρ * π/4 * 1 000 W = codend width Constant Measure at the start of fishing m H = codend height Constant Measure at the start of fishing m ρ = volume-to-mass conversion factor Variable Volume-to-mass conversion kg/litre L = codend length Haul-specific Direct observation m Other Please specify Individual haul when using a conventional trawl, or integrated over a six-hour period when using the continuous fishing system. Individual haul when using a conventional trawl, or a two-hour period when using the continuous fishing system. Observation steps and frequency Holding tank volume At the start of fishing

Measure the width and length of the holding tank (if the tank is not rectangular in shape, then additional measurements may be required; precision ± 0,05 m) Every month Estimate the volume-to-mass conversion derived from the drained mass of krill in a known volume (e.g. 10 litres) taken from the holding tank Every haul Measure the depth of krill in the tank (if krill are held in the tank between hauls, then measure the difference in depth; precision ± 0,1 m) Estimate the green weight of krill caught (using equation) Flow meter Prior to fishing Ensure that the flow meter is measuring whole krill (i.e. prior to processing) More than once per month Estimate the volume-to-mass conversion (ρ) derived from the drained mass of krill in a known volume (e.g. 10 litres) taken from the flow meter Every haul Obtain a sample from the flow meter and: measure the volume (e.g. 10 litres) of krill and water combined estimate the flow meter volume correction derived from the drained volume of krill Estimate the green weight of krill caught (using equation) Flow meter Prior to fishing

Ensure that both flow meters (one for the krill product and one for the water added) are calibrated (i.e. show the same, correct reading) Every week Estimate the density (ρ) of the krill product (ground krill paste) by measuring the mass of a known volume of krill product (e.g. 10 litres) taken from the corresponding flow meter Every haul Read both flow meters, and calculate the total volumes of the krill product (ground krill paste) and that of the water added; density of the water is assumed to be 1 kg/litre Estimate the green weight of krill caught (using equation) Flow scale Prior to fishing Ensure that the flow scale is measuring whole krill (i.e. prior to processing) Every haul Obtain a sample from the flow scale and: measure the mass of krill and water combined estimate the flow scale mass correction derived from the drained mass of krill Estimate the green weight of krill caught (using equation) Plate tray Prior to fishing Measure the mass of the tray (if trays vary in design, then measure the mass of each type; precision ±0,1 kg) Every haul Measure the mass of krill and tray combined (precision ± 0,1 kg)

Count the number of trays used (if trays vary in design, then count the number of trays of each type) Estimate the green weight of krill caught (using equation) Meal conversion Every month Estimate the meal to whole krill conversion by processing 1 000 to 5 000 kg (drained mass) of whole krill Every haul Measure the mass of meal produced Estimate the green weight of krill caught (using equation) Codend volume At the start of fishing Measure the width and height of the codend (precision ± 0,1 m) Every month Estimate the volume-to-mass conversion derived from the drained mass of krill in a known volume (e.g. 10 litres) taken from the codend Every haul Measure the length of codend containing krill (precision ± 0,1 m) Estimate the green weight of krill caught (using equation) A new period will commence when the vessel moves to a new subarea or division. Individual haul when using a conventional trawl, or integrated over a six-hour period when using the continuous fishing system.