Rats

Rats are a pest that affects homes, green spaces, commercial establishments, among others.

Some species can transmit diseases including salmonella and leptospirosis.

They are responsible for countless deaths, namely the Black Death pandemic.

They are omnivorous animals, very adaptable and of great reproductive capacity. A female, in ideal conditions in her habitat, can give life to 2,000 descendants for one year.

Rats and rats contaminate food with urine and excrement and carry numerous diseases in addition to causing major material damage.

There are three types of rodents:

Commun rat

Field rat

Domestic Rat

RATTUS RATTUS

Aspect

  • 16 – 24 cm long, with a tail longer than the head and body together.
  • 150 – 200g of weight.
  • Pointed nose, large ears and thin body compared to the common rat (Rattus norvegicus).

Life cycle

  • 5 – 10 pups per litter; 3 – 6 litters per year.
  • Gestation period of about 3 weeks.
  • 12 – 16 weeks from birth to sexual maturity.

Habits

  • Uncommon in Portugal. They appear mainly in ports.
  • They often climb, are agile, barely dig and rarely live abroad.
  • They prefer to feed on moist fruits.
  • They eat about 15g of food a day and drink 15ml of water.

MUS MUSCULUS

Aspect
  • 7 – 9.5cm long, with a tail of almost identical length.
  • Weight 12 – 30g.
  • With small feet and head and large eyes and ears, it is easy to distinguish it from the common young rat (Rattus norvegicus).
Life cycle
  • 4 – 16 pups per litter; 7 – 8 litters per year.
  • Gestation period of about 3 weeks.
  • 8-12 weeks from birth to sexual maturity
Habits
  • They usually live on land and dig holes, but they also climb frequently.
  • Cereals are their favorite food.
  • They eat about 3g of food a day and can survive without any additional water.
  • Drink up to 3ml a day, if the diet is particularly dry.

RATTUS NORVEGICUS

Aspect

  • Up to 40 cm in length, with a tail shorter than the head and body together.
  • 350 – 500g in weight.
  • Thick nose, small ears and fatter body compared to the black rat (Rattus rattus).

Life cycle

  • 7 – 8 pups per litter; 3 – 6 litters per year.
  • Gestation period of about 3 weeks.
  • 10-12 weeks from birth to sexual maturity.

Habits

  • They usually live on the land and dig burrows, but they also climb from time to time.
  • It is the only species that appears in sewers.
  • Cereals are there favorite food. They eat about 30g of food a day and drink 60ml of water.