Do you know your enemy?
Rats and mice, because transmit many diseases to humans and domestic animals and can cause serious damage to the environment contaminating raw materials, can be considered the last great enemy of the animal kingdom for the modern man.
Black Rat, Roof Rat.
AVERAGE WEIGHT: 150 – 250 g
LENGTH FROM HEAD TO FEET: 16-20 cm
FUR: back grey-black, belly withe.
FEEDING: up to 28 g per day, in a lot of places.
SHELTERS: inside walls, especially in high places, loft, granaries, even on the trees.
The average feeding is 10% of their weight (7 to 15 g) of food on each day.
Like the other commensal rodents, the Rattus rattus or Black Rat is an opportunist, but compared to the Norway Rat it is less dependent from the human food. Especially in semi-tropical areas were vegetation is flourishing, it eats more vegetable food like seeds and fruits, insects or snails. If leaving near water, will feed on fish or shellfish or other aquatic organisms.
Around buildings, the Roof Rats take advantage of any source: outdoor dog pans, garbage bins, overgrown gardens, orchards, citrus groves, bird feeders, livestock feeding operations.
They feed typically at dusk and prior to down although there may be several raids for food each night. Usually, rats forage in family group up to 10 rats, if food and nesting areas are available there can be several hundred of rats foraging in the same area.
When the Roof Rats is foraging, it leaves faecal pellets, urine drops or secretion from uro-genital areas of the body. These contains pheromones which marks the territory, stimulating the use of certain way for gaining the entrance to the structures. Pheromones play a role in stimulating the use of same areas in the years. So it is important to identify these “attractive” positions for the placement of bait stations and traps.
In heavy infestation the high activities areas are saturated with pheromones which assist other rats to utilize locations, food sources, safe entrances and exit ways, safe hiding places, nesting points.
Home range is typically form 7 to 30 m but it can easily arrive to 300 m depending on several factors such as food sources, etc.
Roof rat prefer to feed in protected areas, like under dense vegetation. If the food is placed in unprotected areas, they will carry the food back to the nest or to a secluded area. So, after a roof rat infestation, a stored product infestation is subsequently common.
The Neophobic behaviour in Rattus rattus is generally more pronounced than in Norway Rat. It has hybrid behaviour in eating compare Norway rat and House Mouse: it tends to eat smaller quantity of food from several places.
Roof Rat require water on a daily basis, They dink from 30 to 60 ml. Where vegetation is lush water is normally available. Succulent food like: fruits, slugs, insects etc., may provide part or all water requirements. Inside building water source must be available.