Common pests

The most common species that is encountered is the common rat (rattus norvegicus). 

Facts about the rats

It is by far the most common of the town rat species and is widely distributed in both urban and rural areas. It occurs both indoors and outdoors and is the species associated with sewers. The ship or black rat is rare in this country and confined mainly to port areas.

How do they affect me?

A rat colony will often start with a single pregnant female, and unless there are obvious signs of damage, such as torn packages or droppings, the infestation may not be noticed in the early stages. Except when there are a lot of rats, or food is scarce, they will only come out at night, and daylight sightings are unlikely. Pregnancy lasts about 21 days, and a single female can have a litter of about 6 young. These can feed themselves after 3 weeks, and reproduce when about 8 - 12 weeks old. Mortality of the young is high, but even so, a rat infestation can grow quickly As the number of rats increases, signs of damage become obvious. There is damage to food containers and cartons as rats gnaw at them, droppings (black, about the size of a peanut) become noticeable.

How do you control them?

Check all food packages carefully, and throw out all open packets and any packets that show signs of damage. Transfer new food out of paper and cardboard packaging into mouse proof containers - glass jars with screw lids, or heavy plastic containers with strong snap on lids. Rat traps and cats will only remove some rats without eradicating the infestation and rats are resistant to some of the older poisons on sale to the public. Eliminating an infestation generally requires a specialist pest contractor.