Mule deer are found in a variety of habitats, including forests, woodlands, shrublands, and grasslands. They prefer areas with a mix of open areas and cover, and they are often found near water sources. The forest behind your house is likely a suitable habitat for mule deer, and they may be using it for food, shelter, and reproduction.
The mule deer is a keystone species in the forest ecosystem. It helps to control the populations of other animals, such as coyotes and mountain lions, by providing them with food. The mule deer also helps to disperse seeds, which helps to maintain the diversity of plant life in the forest.
The mule deer is an important part of the forest ecosystem, and its presence is a sign of a healthy environment.