Chipmunk Bolt Hole.........
These holes are quite a phenomenon that I still haven't any answer for. Since my property is a Wildlife Habitat everything is welcome here. We have so many Chipmunks and they are the most endearing animals. But we have so many of these " Bolt Holes " A bolt hole is so they can be able to go underground at a moments notice due to predators being around. Chipmunks live underground in long tunnels up to 12 feet. Each tunnel has specific rooms almost the same way humans live. They have a pantry [kitchen] latrine [bathroom] and sleeping rooms [bedrooms] but each chipmunk lives entirely by itself, they are solitary animals. And very territorial.
Chipmunks in the Northern climates go into a semi hibernation for the winter. So they store food for this period and wake up often to eat. They usually come above the ground in March and leave around the end of October but this all depends on the weather. The females have a couple of litters a year usually 3 at a time I have seen the babies when they come up and their almost ready to go out on their own. The mother teaches them how to run and it is so cute watching them going further and further from their hole until they are off on their own for good. After this they basically hate each other and will fight.
Now for the phenomenon, when they make these tunnels not once have I been able to figure out where the dirt goes. They do not bring it above the ground so where do they put it? This is one mystery that I have no explanation for. It has to be put somewhere but where unless one of my neighbors has a mountain in their yard. This hole was back by my compost bin and there were 3 more just outside the photo it was about 2 inches wide~