Common Rat Species
There are two main types of rats that can cause concern. The Brown Rat (or common rat) and the Black Rat. They are a common pest in both private homes and businesses.
Black Rat
(Rattus rattus)
Black rats are rare and their appearance is usually mainly confined to port areas.
Appearance
- The black rat is between 16–24cm in length, with a tail longer than the head and body.
- It grows to between 150–200g in weight.
- They have a pointed nose, large ears and a slender body when compared to the Brown Rat (Rattus norvegicus).
Life cycle and habits of a Black Rat
Life Cycle
- Black rats produce 5–10 young per litter, and have between 3–6 litters a year.
- The gestation period is about 3 weeks.
- It only takes between 12–16 weeks from birth for them to reach sexual maturity.
Habits
- They often climb as they are incredibly agile.
- It is rare for them to burrow and they are rarely found outdoors.
- Their preferred food is moist fruits. Black Rats will eat around 15g of food a day and drink 15ml.
Brown Rat
(Rattus norvegicus)
Brown rats usually prefer ground living and burrowing, but sometimes they can be known to climb.
Appearance
- The brown rat is up to 40 cm in length, with a tail shorter than the head and body.
- It grows up to between 350–500g in weight.
- It has a blunt nose, small ears and a thicker body when compared to the Black Rat (Rattus rattus).
Life cycle and habits of a Brown Rat
Life Cycle
- Rats have 7–8 young per litter, and between 3–6 litters a year.
- The gestation period is about 3 weeks.
- It only takes 10–12 weeks from birth to reach sexual maturity.
Habits
- The brown rat is the only species to occur in sewers.
- Preferred food is cereals, although they are omnivorous.
- They will eat around 30g of food a day and drink 60ml.