Q: Why are gates installed on abandoned mines?
A: A primary reason is safety. Many abandoned mines are unstable with rotting timbers and collapsing walls. Some mines contain dangerous environments of bad air, dangerous chemicals and hidden shafts. Another very important reason is to protect bat colonies that use these mines as roosts.
Q: What's the difference between a Mine and a Cave?
A: Caves are naturally formed voids in the rock, whereas Mines are man-made structures that have been dug open. Caves are much more stable than mines and last for thousands of years. Mines may only last tens to hundreds of years before they collapse.
Q: Why do bats roost in Mines and Caves?
A: There are a variety of reasons, but one of the most important is the constant temperatures of these underground places. Also, Mines and Caves offer fairly safe roosts to avoid predation by other animals.
Q: How many Abandoned Mines are there?
A: The numbers are unclear since most of the early miners did not record their prospects. The overall number is certainly in the hundreds of thousands if not millions. The state of Arizona alone is estimated to contain over 100,000 Abandoned Mines.
Q: Bats seem to have a bad reputation, why are bats important?
A: Historically bats have had bad connotations, but this was really based in ignorance about this unique little mammal. Bats play a hugely important role in controlling insect populations. Some species of bats eat half their body weight in insects every night. That's a lot of pest control. Other bat species are critical in pollinating certain species flowering plants. The desert Saguaros rely heavily on bats for their pollination and continued existence.
Q: Who decides if a Mine or Cave will be gated?
A: The land owner or land manager where the mine or cave resides makes this decision. Normally on government lands a biologist will inspect and inventory the site, and then make recommendations on the best solution for that specific site.
Q: Is it illegal to modify a gate for entry?
A: Passing a gate without permission is normally considered breaking and entering, and is a felony in many states. Nothing you will see on the other side of a gate is worth the risk. Most mines that are gated are done so mostly for safety issues. Most mines contain very little of interest anyway.
Q: Do snakes have eyelids?
A: No, snakes do not have eyelids. Some rodents take advantage of this fact in their get-away strategies. They will kick dirt in the face of an attacking snake and then dart away to safety.
Q: Do bats have any problems flying through gates?
A: Bat-friendly gates have bar spacing gaps of 5 3/4 inches, which is large enough for even large bats to fly through. Some species of bats seem to not like gates very much, but the research on this is still being debated. Animal behavior is a difficult thing to precisely determine, since there are so many variables that might affect the outcome of a research experiment.