What is the author referring to when he says 'real monkey on a stick'?

I think that is a persin on a pole sinking into the river.

The writer had an interesting story to tell when he was punting with his friends. A young man was walking up and down the punt, working with his pole with a careless grace that was quite fascinating to watch. " Up he would march to the head of the punt, plant his pole, and then run along right to the other end, just like an old punter."

while punting he looked round to enjoy the scenery,Mistakenly he took a step further without noticing and walked off the punt altogether. The pole was firmly fixed in the mud and the man was left clinging to it while the punt drifted away. " A rude boy on the bank immediately yelled out to a lagging chum to " hurry up and see real monkey on a stick "