Los Guatuzos Wildlife Refuge (Spanish: Refugio de Vida Silvestre Los Guatuzos) has an area of 437.5 km2 (168.9 sq mi) and is located south of Lake Nicaragua and west of the San Juan River in Nicaragua.

[3] The site has been catalogued by UNESCO as a biosphere reserve and belongs to the list of cenagales (wetlands) of international importance of Ramsar Convention.

It also has a butterfly farm, turtle and caiman nursery, and an orchid display of 92 different species.

Some of the commonly spotted animals include caimans, crocodiles, jaguars, monkeys and feral pigs.

The Atractosteus tropicus, or gaspar, has fangs and a snout that help it consume other species of fish as well as turtles and crabs.