This panel manages all the parameters for dispersal during growth or reproductive season.
The first group of options let the user change the probability to move from a reach during growth season, and during reproductive season. This probability is given per month. The user can also change the symmetry of dispersal. Finally, the user can change the probability that an individual will use a homing migration type during reproduction: this migration is directed toward the reach of birth, and the fish will attempt to reach its birth place by the shortest path possible.
The second group of options describes the connectivity or “passability” parameters. Roughly, the score for passability can range between user specified boundaries, but the range cannot exceed [0,128]. Using a large range just helps to have a more progressive scale for the difficulty to cross obstacles. The passability for each weir is provided by the user in the inventory file, and the maximum passability is updated based on these data. However, the user can also, from this panel, change the value of this maximum, therefore applying a general modification for connectivity in the whole watershed.
The last group of options let you tune the migration process during reproduction for non-homing fish. Fish will migrate upstream without having a specific direction, on a given reach number each month. If desired, they can sample habitat quality (here the substratum score, ranging between 0 and 20) to decide if they settle in a reach.