Black and brown rats are considered omnivores and eat a wide range of foods, including seeds, fruit, stems, leaves, fungi, and a variety of invertebrates and vertebrates. They are generalists, and thus not very specific in their food preferences, which is indicated by their tendency to feed on any meal provided for cows, swine, chickens, cats, and dogs. They are similar to the tree squirrel in their preference of fruits and nuts. They eat about 15 grams per day and drink about 15 ml per day. Their diet is high in water content. They are a threat to many natural habitats because they feed on native birds and insects. They are also a threat to many farmers since they feed on a variety of agricultural-based crops, such as cereals, sugar cane, coconuts, cocoa, oranges, and coffee beans.

Through the usage of tracking devices such as radio transmitters, rats have been found to occupy dens located in trees, as well as on the ground. In some areas, rats have been found to form dens together. Rats appear to den and forage in separate areas in their home range depending on the availability of food resources. Research shows that in wooded areas, the black rat prefers to inhabit lower leaf litter of forest habitat. There is also an apparent correlation between the canopy height and logs and the presence of black rats. This correlation may be a result of the distribution of the abundance of prey as well as available refuges for rats to avoid predators. As found in leafy forests, there is a positive correlation between rat abundance, leaf litter cover, canopy height, and litter depth. All other habitat variables showed little to no correlation. While this species relative, the Brown (Norway) rat prefers to nest near the ground of a building the black rat will prefer the upper floors and roof. Because of this habit, they have been given the common name Roof Rat.

In a suitable environment, it will breed throughout the year, with a female producing three to six litters of up to ten young. Females may regulate their production of offspring during times when food is scarce, producing as few as only one litter a year. R. Rattus lives for about 2–3 years. Social groups of up to sixty can be formed.

Rats and roof rats are a difficult pest to tackle. We recommend being proactive and getting rid of excess trash and not leaving food on counters. If you have a rat infestation, please don’t hesitate to call us and set up a free consultation to see what we can do and recommend specifically for you. For more information about how to handle these particular pests, click below!