Kevin Rushby visits an artists' colony on the vast Lake Nicaragua then heads down the San Juan river in search of caimans and a lizard with divine powers View a slideshow of the trip here 'You know about Jesus Christ?" asks Don Pedro in a whisper, the beam of his headtorch strafing the riverbank. I nod. It's a filthy black night. It's raining. We are on a big fast river, the Rio San Juan, in the ...