Appearance:

• Combined head & body Length: 200 – 270mm
• Average weight: 250-500g. (Max 700 gms)
• Coarse brown (occasionally black) fur, with a pale underside.
• Tails are 150 – 210 mm.-
• Blunt nose, small ears with a tail shorter than the head and body.Lifecycle
• Sexually mature at: 8 – 12 weeks.
• Gestation period: 21 – 24 days.
• Litter size (average): 6 – 11.
• Weaning period: 3 – 4 weeks.

Lifecycle:

• Can live up to 18 months in the wild, but 3 – 4 years domestically.

Habits & Behaviour:

• Rats are very adaptable and can be found in a variety of habitats, usually in close conjunction with humans. Burrowing, but sometimes climbing they are the only species to occur in UK sewers.
• Norway rats are omnivorous eating fish, vegetables, weeds, earthworms, nuts and fruit, but prefer protein-rich foods, such as cereals.
• They will eat around 30g of food a day and drink 60ml.
  Rats are typically nocturnal, although they will sometimes forage for food
• during the day if colonies become too over populated.
• They live in loose colonies, made up of aggregations of clans – usually defending their territory from other rats – the biggest rats are dominant over their smaller counterparts.
• Brown rats swim well and are sometimes mistaken for water voles. They have well-developed senses of hearing and smell.

Important:

• As with mice, look out for holes, droppings, smear marks and unpleasant smells as these are signs a building may be being used as a run.
• They are subject to persistent pest control due to the damage they cause and the numerous diseases they spread.
• Along with house mice, they are considered to be the most widespread terrestrial mammal.

Appearance:

• Combined head and body length: 70 – 90mm.
• Mice usually less than 23g (average 15 – 18g)
• Length of hind feet: 16 – 19mm- Brown-Grey fur, with slightly lighter under-parts.
• House mice have large ears, a pointed nose and the tail is usually around 80% length of the head and body.

Lifecycle:

• Sexually mature at: 8 – 12 weeks.
• Gestation period: 17 – 20 days.
• Litter size (average): 5 – 6.- Weaning period: 3 weeks.

Habits & Behaviour:

• Mice are usually ground living, found in areas near to human habitation nesting around the undisturbed parts of buildings climbing through wall cavities and voids using them as tunnels.
• They are also found in open fields burrowing, building complex tunnel systems with several exits.
• Mice are omnivorous but prefer to eat cereals and insects.
• They will eat around 3g of food and drink up to 3ml a day if their diet is particularly dry, although the can survive without any additional water.
• Mice are typically nocturnal, although they will sometimes forage for food during the day if colonies become too over populated.

Important:

• Look out for holes, droppings, smear marks and unpleasant smells as these are signs a building may be being used as a run.
• Mice are subject to persistent pest control due to the damage they cause and the numerous diseases they spread.
• Along with rats, they are considered to be the most widespread terrestrial mammal.