Old man in a canoe in the middle of a lake .
Along comes a fisheries officer in his power boat

He pulls along side the canoe and sees a fish in a pail between the old man's legs .

A conversation ensues .

Sir , do you have a fishing license ?

No officer , I do not.

Explain why you have a fish in that pail !

Well Sir , that is my pet fish .

Really ?

Yes Sir . Every day around this time I bring him out to the middle of the lake and slip him in to the water so he can have a good 10 minute swim . I have taught him to return to the boat when he hears a special sound .

You can't expect me to buy that bull !

Well , that is my story .

You will have to prove it or you are going to be cited for fishing without a license.

Okay Sir. ( the old man slips the fish in to the water. The Fisheries officer starts timing the swim . Ten minutes expire )

Okay old timer , make that " special sound " that calls your fish back

What fish ?