I grew up in west texas and observed fish appearing in stock tanks under wind mills. There was no way that the fish could have swam into the tanks during a heavy rain because the tanks had three foot sides. We were told that birds brought the fish eggs into the tanks by a local biologist. The fish that were in the tank were too small to have been caught with a rod and reel and then put in the tank. This leaves only two possible causes A.)someone put small minnows in the tanks by catching them with nets B.)Birds brought them in.
