Slendor-Nosed Crocodile or Slendor-Snouted Crocodile are listed as critically endangered by the IUCN. That means they are on the brink of extinction. Yet on this one river in Gabon, they're surpisingly common. You can only visit this are by boat and this is by far the most common sight in this national park.
Loango National Park, Gabon July 2019