Sphinx Cave - Bat Gating Project
Coronado National Forest, Arizona.

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A few nearby holes between rocks near the installation site were also sealed off to prevent and discourage digging around or possibly breeching the gate. These were reinforced with re-bar and concrete, drilled deeply into the surrounding rock and set in place with concrete footers. The steel bars were left far enough apart that bats could still fly through these windows, but they are small enough to keep out human visitors. These windows are not along the normal bat flight path, but we try to keep them open for the occasional bat and to leave airflow in its natural state.


Window Closure

Small Passage Window Closure


Bat on Ceiling

Bat Roosting with Pup


Several types of bats use the cave seasonally throughout the year. This particular region gets heavy visitation from bats as they migrate to and from lower latitudes. Large colonies of Townsend's Big-eared bats often use the cave for roosting during the summer. Unfortunately, the accumulation of expended shotgun shells and other debris inside the gate area, indicate recent increased visitation and disturbance of these bats. People need to understand the great value bats have in our local environments. Many species of bats will eat half of their body weight in insects every night. This is a huge advantage in keeping down the populations of pest insects. Other bats in this region prey on scorpions and centipedes, which also helps to reduce the number of these pests. And some species found around this cave play an important role in pollinating our beloved Saguaros and other desert cacti. We feel that it is very important to support and protect these often misunderstood mammals, and by protecting the caves they live in, we are making our world a better place.


This is a photo of the completed gate. Notice the bat flying through the gate bars. Several large groups of bats have been recorded residing in the cave a year after the gate's installation.

Partial funding for this project was provided by The Department of Agriculture, U.S. Forest Service and the Southern Arizona Grotto. Fabrication and installation work was performed by MineGates, Inc., with the help of volunteer cavers of the National Speleological Society, Southern Arizona Grotto and the USFS Coronado Forest. This project is an example of multiple group cooperation, including Federal agencies, private organizations and volunteer groups coming together to accomplish a common goal. Thank you to all those who helped out on this project.


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Finished Bat Gate

Finished Gate with a Single Bat Flying Through the Bars


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