I'm curious what would possess someone to come to the big lake for fishing. At this same time, relatives of mine were operating a fishing resort near Park Rapids, and I get the sense that there was a well developed fishing-centric tourism industry there. But I always had the idea that Duluth didn't come into its own tourism wise until the last few decades. 

Maybe these people were outliers. They seem to be launching from a small-commercial scale landing slightly up the shore from the canal. Any details on the source?

I am pretty sure the first fishing trip was out of Knife River. Trolling on Superior with oars is gutsy if you ask me. And it looks to me like the guy at the end was using a salami as a phallic symbol to the amusement of all. Also the Chico Marx hat he sports is something else. 

I do remember driving up to Rice lake with the old man and renting a wood row boat for a buck and rowing to the fishing hole. Slow hard work and you need to bail a bit. That would be in the 60s.