Trout
From UnReal World Wiki
Trout, along with salmon, are the biggest fish you can catch in URW. They can only be caught in deep water or rivers, and fishing in rapids may give a better chance of catching them. 1 lb of trout can fill nearly all of your hunger bar. Each trout is usually 4-5 lbs, and can be caught in nets.
A pile of 19 6-pound salmons cost one cord to dry or smoke, same as 19 perches or 19 meat cuts. Therefore it's most economical to dry/smoke salmon/trout instead of meat. The drawback is that you need to be a fairly good fisherman: 10+ Nets, 2 fishing's chants, raft or punt, one fireplace, one wall, and one floor/ceiling tile next to the fireplace.