Wildlife types at Saguaro National Park are extraordinarily diverse, reflecting the Park's ecologically strategic location.  The (east) Rincon Mountain District lies at the interface of the Sonoran and Chihuahuan deserts, and is part of the chain of scattered "sky island" mountaintops in southeastern Arizona and northwestern Mexico that connect the Rocky Mountains to the north with the Sierra Madre Mountains to the south.  Wildlife from all of these biomes are represented in Saguaro National Park.

The Rincon Mountain District ranges in elevation from 2,680 to 8,666 feet, and encompasses six structurally distinct biotic communities;  while the (west) Tucson Mountain District ranges in elevation from 2,130 to 4,687 feet, and contains two separate biotic communities.

Overall, Saguaro National Park supports a unique and diverse assemblage of thousands of invertebrates, and more than 325 vertebrates -- including approximately 70 mammal species, 200 species of birds (including 18 species of hummingbirds), 50 reptile species (including 6 species of rattlesnakes), and 8 amphibian species.  The challenge in maintaining this biodiversity is underscored by the fact that since the early 20th century, desert bighorn sheep, Mexican gray wolves, jaguars, grizzly bears, and Gila topminnows have all been extirpated from the Rincon Mountain District, while the Tucson Mountain District has lost desert bighorn and white-tailed deer.

Urbanization and development increasingly surrounds both districts ofSaguaro National Park.  Habitat fragmentation and isolation of Park habitats requires Park managers to focus on the need to maintain connective corridors for wildlife in order to sustain native biodiversity.  The National Park Service must regularly undertake scientific wildlife and habitat research in order to make informed management decisions.

In recent years, Friends of Saguaro has provided funding for research to conduct the comprehensive Saguaro BioBlitz;  complete a 5-year ecological study of mountain lions and bobcats in the Tucson Mountains;  conduct an ecological "pulse survey" at the Madrona Pools in the RMD;  support Sonoran desert tortoise research;  pursue surveys of Saguaro's population of endangered lesser long-nosed bats;  and conduct extensive surveys of Gila monsters at both districts of the Park.

Learn more by checking out the Park's website at http://www.nps.gov/sagu/