A man was stopped by a Game Warden in Northern Minnesota with two buckets of fish leaving a lake well known for its fishing.  The game warden asked the man, "Do you have a license to catch those fish?"
 
The man replied, "No, sir. I don't need a license."

Irritated, the Game Warden said, "You are over limit and fishing without a license.  I'm going to have to arrest you and confiscate those fish to use as evidence!"

The man stood his ground and replied, "I don't need a license. These are my pet fish!"
 
"Pet fish?" the warden said.
 
"Yes, sir. Every night I take these fish down to the lake and let them swim around for a while.  I whistle and they jump back into their buckets, and I take em home."
 
"That's a bunch of hooey!  Fish can't do that!"
 
The man looked at the game warden for a moment, and then said, "Here, I'll show you. It really works."
 
"O.K. I've GOT to see this!" the game warden replied.
 
The man poured the fish into the water and stood and waited.  After several minutes, the game warden turned to the man and said, "Well?"
 
"Well, what?" the man asked.
 
"When are you going to call them back?" the game warden prompted.
 
"Call who back?" the man asked.
 
"The FISH!"
 
"What fish?" the man asked as he turned to leave.