To understand the audit results, the following definitions are useful:
Y1 – year one fish, these fish have spent one year or less at the saltwater site
Y2 – year two fish, these fish have spent over one year at the saltwater site
Abundance – average number of lice per fish examined (e.g. if one fish has three lice and nine fish have no lice then the abundance is 0.3 lice per fish).