Roof rats are common rodents found globally, especially in coastal and southern regions. Understanding their behavior helps identify their presence.
The Night Life of Roof Rats
Roof rats are primarily nocturnal, active after sunset and before dawn. This behavior is an evolutionary adaptation, allowing them to avoid diurnal predators like birds of prey and to utilize the cooler, darker conditions for their activities. If a roof rat is seen during daylight hours, it can sometimes indicate a large population or a significant food shortage, compelling them to forage more broadly.
At night, roof rats forage for food and water. They are omnivorous, consuming seeds, nuts, fruits, berries, insects, slugs, and snails. They often hoard food. They find water in sources like leaky pipes, birdbaths, or pet water bowls.
Movement between nesting sites and food sources is a significant nighttime activity. Roof rats use established pathways, traversing utility lines, fences, and tree branches. Their excellent climbing abilities enable them to access elevated areas. Social interactions occur within their colonies, and they communicate through squeaks.
Recognizing Roof Rat Presence and Behavior
The nocturnal habits of roof rats contribute to specific signs that indicate their presence, making direct sightings less common. One of the most noticeable indicators is the sounds they produce, particularly at night. Homeowners often hear scratching, scurrying, or gnawing noises from attics, walls, or ceilings as the rats move, forage, and build nests. They may also squeak.
Another clear sign of roof rat activity is the presence of their droppings. These are typically small, dark, and about 0.5 inches (12-13 mm) long, with pointed ends, often resembling grains of rice. Unlike Norway rat droppings, which are larger and have blunt ends, roof rat droppings often have a tapered or pinched appearance. Droppings are commonly found near food sources, nesting sites, or along their travel routes.
Gnaw marks are a frequent indicator. These marks can be found on electrical wires, pipes, wooden beams, insulation, and cardboard boxes. Roof rats also leave greasy rub marks on frequently traveled surfaces like walls, baseboards, and pipes.
Roof rats are highly adept climbers, a trait that directly influences their preferred nesting sites. They use sharp claws and long tails for balance to scale vertical surfaces. This leads them to establish nests in elevated locations, including attics, rafters, eaves, wall voids, and dense outdoor vegetation. This preference differentiates them from Norway rats, which are typically ground-dwelling and create burrows.