When our original excursion was cancelled, we hastily beat a path to the shore excursion desk and booked a 7:15 tour to Tortuguero Canal known as the Amazon of Costa Rica.  It was a fascinating trip down the canal.  As our boat made its way down the river we discovered howler monkeys, sloths, birds of all sorts and a crocodile.  It was an exciting tour.  We were blessed to get the first tour as we were told that by the time the river gets saturated with boats, much of the wildlife retreats into the jungle.