I missed the execpt salmon part in freshwater.
I found this though from dfo.
http://www.pac.dfo-mpo.gc.ca/fm-gp/rec/points/packaging-emballage-eng.htmPackaging your Salmon
Chinook, Coho, Pink, Chum, & Sockeye
When packaging your catch, if a maximum size limit applies, the head and tail must remain attached until you prepare and consume your catch, arrive at your ordinary residence, or deliver your catch to a registered processing facility.
The head of your salmon can be removed only if the length with the head off is equal to or greater than the minimum legal size of that species for the waters in which it was caught. Leave the tail attached so species can be determined. For example, if a Chinook salmon is caught where the minimum size limit is 62 cm and it is filleted and packaged for transport, one of the fillets must have the tail attached and be at least 62 cm long.