What are some distinguishing characteristics between the two. If I didn't know any better I would say a sucker is a trophy whitefish.

Two entirely different critters. Both are considered edible depending on where you live.


http://en.wikipedia.org/wiki/Whitefish

http://en.wikipedia.org/wiki/Catostomidae

Quickest give away is the adipose fin displayed by the whitefish whereas the sucker has no such fin.

Good thing to remember too. The way our fish stocks are going, we are going to have selective fisheries on ad clipped whitefish as the only fish available to target in the not-so-near future.

Suckers fight harder.

I dont know... i had a monster WF slam a colorado under a float sooo hard

Whitefish have a tiny mouth. Suckers have a large mouth (sucker) that opens down toward the bottom.

I know they are different sizes but you would expect a mouth to get bigger with the body of a fish. I have never caught a sucker the size of a white fish or the other way around so that is why I was thinking that they are both whitefish but a sucker just matures, colors up, and grows a bigger mouth. Now I know better, i'll just look at the adipose.

Pound for pound..(Prosopium williamsoni) or the mountain white fish do fight harder than the suckerfish common to our rivers. Have caught some 18-22 inch YT's while fly fishing on the east side.. They can fool you for a couple minutes.

A few years back side drifting the cowlitz for steel I landed a YT that had to push 5lbs... fought much better than the suckers you can occasionally hook down there of similar size.