Our Wild Neighbors

Norway Rat

Rattus norvegicus

Established Canadian resident

Image of a Norway Rat, seen from the side with its head to the left, mounted on a base with some twigs.

Description of the animal

  • Short, stocky rodent.
  • Length: body about 25 centimetres, tail about 20 centimetres.
  • Weight: about 350 grams.
  • Brown or grey fur, lighter-coloured belly.
  • Scaly, ringed tail.
  • Long whiskers, piercing black eyes, and small claw-like feet resembling human hands.

Habitat and needs

  • Active at night: nocturnal and quiet.
  • Matures in a very hierarchical group in cities in damp environments like sewer systems.
  • Eats pretty much the same food as humans, and seizes the opportunity to do so!
  • Has a life expectancy of about a year, long enough to give birth to about 60 offspring.


  • The Norway Rat is regarded as the most destructive rodent in Canada.
  • It poses a threat to food, water pipes, and electric and telephone cables. It can also transmit diseases to humans.
  • Albino rats are used in laboratories, especially for pharmaceutical research.
  • Some are adopted as pets and kept in cages.

Living with them

  • To prevent the Norway Rat from moving into a home, food and garbage must always be stored in metal or rigid plastic containers with airtight lids.
  • In case of infestation, set traps, block holes, move stacks of wood further away, and remove birdfeeders (the Rat is particularly fond of them), along with discarded items that may be used for shelter.

Participating cities where this animal has been seen