I release fish too, but it really depends on a few things as I'm more "Selective Harvest" when it comes to keeping fish to eat, or to use as bait; The bigger the fish is, the more likely I'm putting it back. Mainly because bigger females can fit a lot more eggs and put more back, and bigger ones are the genetics I'd like to see. Anything around that 20 pound mark is going back in the water. But also smaller fish go back too depending on what they are; Small Perch, a pound or less, that's really good live bait, and for Sunfish species, we have no size limits but if I saw a massive Sunfish I may put that back, but if I see a Flathead swim by he may go back with some new piercings LOL. Walleye would have to be pretty damn big for me to put it back though; They are the most abundant species we have, and catching even a 5 or 6 pound one isn't really something rare, so either I'm eating it, or I'm gonna try and feed it to a Flathead, or Pike, or Musky, or a Sturgeon.
Sturgeon will go back no matter how big or small they are; Apparently I've eaten one before (I was really young, my Grandpa got one, it's legal to keep one a year here per fishing license) but they aren't so common that I'm OK with keeping one yet. Musky.... Depends. If I land a huge Tiger Musky, I want that to go back AFTER I've got a tape measure and weight and picture so I can have a Fiberglass copy made cause those are PRETTY!
Trout..... Sorry about your luck cause Catfish love you. Also it's a legal way for me to give the DNR a big middle finger (Michigan only has Lake Trout in terms of native fish, I want Blue Catfish in the Great Lakes, DNR questioned my sanity when I brought it up, and said they already have problems with Catfish eating the Trout and would NOT consider it even though they're eating invasive predators that just happen to help sell expensive out of state fishing licenses and even more expensive graphite rods to catch these teeny tiny little fish because they jump....) LOL sorry about the rant, but no, I have very little intention of releasing ANY Trout. Not that I'm trying to choke to death on all those bones, but they don't bother Channel Cats or Flatheads so I'll feed them to them
Salmon....Again, lock and load!
Pike I'd put back if it was small like a Pickerel or a nice trophy size. Same with Carp even though the DNR won't allow us to use them as live bait (They don't want Carp getting off the hook and swimming to where the Trout are...... *sigh*) so the best Musky and Flathead baits are not legal, and the Corn you'd use to catch the Carp isn't legal in Trout Streams either..... *sigh* And even though I've never seen any Trout EVER caught in the main river I fish, because of the Trout, no corn, no chumming, nothing.... LOL I see a pattern here of irritation but yes, at the very least, the DNR agrees with me on Sturgeon. I've also offered to help with their stocking efforts but I don't think that'll happen LOL.
Michigan isn't the only DNR I've gotten annoyed with; I also emailed the DNR for Texas and Florida to make sure they understood that they can piss and moan all day about Amazonian Red Tail Catfish being invasive and being caught in their rivers, and I also pointed out that it's one of the main reasons I'd ever visit Florida because I can catch one without trekking off into the JUNGLE to do it. Texas also has the Trinity River with Alligator Gar that I'd also like to catch, and even though Michigan used to apparently have them, they're from what I know, locally extinct, cause, you know.... Big fish, doesn't have the word "bass" in it's name, so it's scary and must be destroyed.... (Florida also has Peacock Bass from the Amazon invading, but, it's got bass in the name so they're now a designated game fish, even though they're actually a species of Cichlid ...) LOL.
I think I can win though; I'm gonna get some Tiger Shovelnose Catfish, and say they're "Flatheaded Bass" and then maybe they'll be considered game fish like the other invasive species LOL.