Atlantic salmon farm employees are required by regulation to examine their fish every two weeks, at a minimum, for regular sea lice counts during March 1 to June 30, to coincide with Out Migration of wild salmon. If those counts show an average of three motile lice per fish, companies are required to take action to reduce the absolute lice count over subsequent weeks. This means either treating the fish (see “Treatments”) or removing them, if a harvest is planned.
When exceeding the three-motile abundance, numbers and the planned management response must be reported to DFO within 7 days.
https://seawestnews.com/bc-salmon-farms-and-sea-lice-management/