He may or may not have been pulling your leg, but I have eaten a lot of canned carp. Way back when I was a kid we didn't have a freezer and we only went to town about every two weeks. Beef was a rare treat, so canned carp was a welcome change from cured pork. There was a large creek (crick was the local term) that ran through our farm. When the carp were rolling in the fall Dad, and many other folks in the area, harvested lots of them by various means. While I don't remember the exact method she used Mom canned them in glass quart jars and pressure cooked them, similar to canning greens beans. I think she just put chunks of fish in a jar added a little salt and filled it with water. The pressure canning process cooked the bones until they were hardly noticeable. If they are out of clear water the taste does resemble salmon, and is used pretty much the same. I have eaten a lot of carp croquettes and carp loaf.