Overnight we sailed north up the channel between Isabela and Fernandina arriving about dawn off the beach of Punta Tortuga Negra. We had been allowed the very unusual privilege of being permitted to land on this beach which is one of the few sites where the critically endangered Mangrove Finch can be found; there are another one or two sites on Isabela and it has recently been re-found on Fernandina just across the channel though some dispute this. The number of Mangrove Finches may be as small as 40 pairs. We quickly found one singing bird which gave good views but poor photographs; another two or three birds were heard calling but could not be located in the impenetrable tangle of mangroves.