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House mouse

Scientific name: Mus musculus

The house mouse has greyish-brown fur with longer over hairs. It is recorded throughout most of Great Britain and Northern Ireland but it less ubiquitous than commonly thought. It was probably introduced to Britain in the Iron Age.

Taxonomy chart

Animalia - Chordata - Mammalia - Rodentia - Muridae - Mus - M. musculus

Conservation status: UK Red List

GB: N/A

England: N/A

Scotland: N/A

Wales: N/A

Global: Least Concern

Species information

Habitat: Most commonly found in building within the British islands and found in chicken and pig farms. 

Description: Grey- brown fur and has long over-hairs. 

Size: Head and body length 70-90mm, hind foot length 16-19mm.

Weight: Considerable variation in weight on individuals.  

Origin and distribution

Found throughout Great Britain and Ireland, including many islands.

Diet

Omnivorous though cereal foods are preferred to low carbohydrate foods. Insect are substantial part of diet for individuals not living near farmlands.

General ecology

Communal nesting in females of same breeding groups, most often 2 females, that will both nurse young indiscriminately. Young are born naked of fur, blind, pink and weigh as little as 1.5g. Develop quickly, fully weaned by 23 days. Predators are domestic cats, rats and barns owls. 

Breeding

Litters of varying size (between 5-8) are born in roughly monthly intervals in buildings , however, when not near buildings females produce young only in the warmer summer months. 

Conservation status

According to the Mammal Society’s 2018 study, there is a stable population of the house mouse within the UK and Ireland. Their populations experience a ‘boom and bust’ cycle in reproduction making population estimates hard to get exact numbers for the population.  

Download resources

General fact sheet

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