Another Ole from Minnesota joke...
Ole was down at the pond where he often was catching some fish by hand, a skill he'd developed as a kid in Norway. Sitting next to him was a bucket with some of his catch.
He's just sitting there watching for movement in the water for his next catch when a ranger comes up behind him and says, "Hey there old man, you got a fishing license?"
Ole looks up and says, "Vat fir?"
The ranger responds, "You have to have a license to fish in these waters."
Ole looks up and says, "I'm a nat fish'in. Dees here are my pet fish. I'm a just given dem some exercise ya know!"
The ranger says, "Huh? Pet fish, and you're giving them exercise? You have to be kidding me!"
Ole says, "Ya. Vee do dis all da time. I bringa dem downa here to da pond, let dem loose in da pond, day svim around a bit, dem I whistle and day jumpa back into da bucket anda vee go home!"
The ranger says, "Yeah, right old man. I gotta see this!"
Old say, "Sure, I do it fir ya right now." He then goes over places the bucket in the water and lets the fish go. He then puts the bucket down and sits there for a while.
The ranger is waiting there for a few minutes, watching but nothing happens. He then says, "Well, what about it old man?"
Ole says, "Vat about vat?"
The ranger responds, "When are you gonna call back the fish?"
Ole looks at him puzzled and says, "Vat fish?"