Distribution — the krill swarm model

Module 1 builds a three-dimensional field of Antarctic krill swarms. Krill are stored as discrete swarm objects (boxes positioned in space), not as a fixed grid, so the field keeps its natural patchiness. You can build a field three ways:

• By total biomass — set a target in tonnes and the field is scaled to match it exactly.
• By column density — set a mean (and spread) of depth-integrated density in g/m².
• By swarm characteristics — set the swarm size, depth, packing density, and krill length distributions directly.

Once built, the field can be flown over by a virtual acoustic transect survey (per-transect mean and CV, aggregated to management units), and its total biomass and krill length frequency are handed to Module 2 for stock assessment.

Enter Module 1