The forest was given further protections as a nature reserve on October 16, 1985, by the Puerto Rico Planning Board (Spanish: Junta De Planificación), and all provisions from Law No.

[4][6] The Guánica State Forest is of great natural complexity and scientific importance as it serves as a critical habitat to numerous species of animals and plants that are unique to the region.

[4] The last remaining natural population of Puerto Rican crested toads (Peltophryne lemur) can be found in the intermittent freshwater pools which are created by seasonal rains.

This species proliferates in the natural conditions created by the karstic geology of the forest, and current efforts by the Association of Zoos and Aquariums (AZA) include breeding programs and projects to release individuals of this species in similar ecosystems in Coamo and in the Northern karst of Puerto Rico.

Fishing and biking are allowed in special designated areas, while scuba diving is also popular in the coral reefs and in the beaches.