How do you catch canned salmon? Whenever I go salmon fishing, I’ve always had to use a hook and catch them live.
Poorly written sentence by the "journalist".
You can them the same as any other garden produce or meat.
I remember a Bob Hope war comedy. The supply ship with the beer goes down, Hope figures out the currents, and finds a cove full of beer cans.
Perhaps a cannery ship went down off the coast, and Damian's father "caught" such cans of salmon before the tide change?
Either that, or the father actually did the home canning thing - pressure cooking Ball jars of the salmon he caught.