Guayabo Island Biological Reserve

Guayabo Island Biological Reserve (), is a protected area in Costa Rica, managed under the Tempisque Conservation Area, it was created in 1973 by executive decree 2858-A DEL.
It is the location for many nesting sites for brown pelicans as well as various other species of birds.
Nearby are the Negritos Islands Biological Reserve in the same Tempisque Conservation Area, and Pájaros Island Biological Reserve managed under Central Pacific Conservation Area.