No sooner have I dropped the little chunk of prime tenderloin in the muddy water than the battle begins.
It starts with a teasing nibble but quickly becomes a ferocious tug of war as the ravenous little fish gets a hold of the hook and the line is quickly veering in all directions.
A solid jerk on the line and he's stuck. I flick the rod, really just a bit of pointy stick with some line crudely tied, and a flash of silver and red is flying into the boat.
Ola! exclaims Roland our field guide, this is the big bad boy of the Amazon. He's only a few hundred grams, but the short-nosed, red-bellied piranha is the nastiest little brute in the family, of which there are 35 known species. His razor-sharp fangs will easily take off the end of your finger.
I'm travelling aboard the 40m, 400 tonne MV Aqua, based at the river port of Iquitos in Peru's northeastern state of Loreto, the last word in luxury river cruising in these parts. With just 24 passengers doted on by the same number of charming crew and guides, Aqua transports us into remote primary jungle wilderness inaccessible by any other means.