Habitats and Behavior

Habitats: Roof Rats live about 90% of their lives above ground. They spend much of their time in trees or other thick vegetation off of the ground. Any good cover with small hiding spaces will do. Woodpiles, debris, and garbage piles make great habitat. People don't often see rats out in the wild, because they are nocturnal, and because the slink around in the shadows, and in the heaviest vegetation. They dart from place to place quickly, when they sense that it is safe. When they sense a threat in the area, they will often hold still.

When rats live in buildings, they usually choose the uppermost areas. The attics of homes and buildings are ideal. Although Roof Rats will commonly enter buildings at ground level, and although I have caught many with ground level traps and in crawl spaces under homes, Roof Rats prefer to be up high. They will often use a ground level entry point to gain access to the structure, and then climb up walls or pipes to get into the home. They just love to live in attics. Note the brown smudge/stain on this pipe in the photo to the right which rats habitually ran across.

Behavior: Rats tend to be very shy and cautious animals. When confronted with a new object in their environment (such as a trap), they will often avoid it for days until they are used to its presence in the area. Rats usually travel the same pathways over and over and over. This is because once they have found a proven safe route, they stick to it. They also have poor eyesight, but they leave behind a strong pheromone odor telling them where to run. In this photo to the right, rats were running up the same wires over and over again to get into the attic, so a trap on the course captured

it. They secrete oil from their fur, and this leaves the scent behind, along with brown smudges. Of course, they also make use of urine markings. Rats tend to follow this scent, which they can detect for years, to find previous rats' entryways into buildings. In fact, rats tend to establish a "scent scape" that helps them maintain familiarity with their environment. This is why is is very important to deodorize an attic that rats have been living in. Rats are considered colonizing animals within groups, and that is the reason why attics can contain several of them. However, they do exhibit territorial characteristics. In most of the cases that I deal with, there are only a few rats living in an attic.