Crocidura russula | Greater White-toothed Shrew



Conservation status

Least concern

Native status


First reported in the wild



Invasive species - risk of Medium Impact

Irish status


Introduction pathways - 1


Invasive score


NAPRA Ireland risk assessed


Species Biology


Larger than the native pygmy shrew (Sorex minutus), greyish or reddish brown in colour with prominent ears and long, white hairs on the tail (Churchfield,2008).


Feeds on a wide variety of invertebrates (Churchfield, 2008). Studies have shown that it has a negative impact on the abundance of wood mouse (Apodemus sylvaticus)and the occurrence of the pygmy shrew, though the mechanism is unclear (Montgomery et al., 2012), with the pygmy shrew completely absent at sites where C. russula is established. It appears to a positive impact on the occurrence of the bank vole (Myodes glareolus), which may contribute to the effects on the other two species.


Woodland, forest and other wooded land; Regularly or recently cultivated agricultural, horticultural and domestic habitats; Grasslands and lands dominated by forbs, mosses and lichens


Litter size typically 2-11 with a mean of 4, producing several litters a year with a gestation period of 28-33 days (Churchfield, 2008).

Pathway and vector description

It is not known at present how this species entered Ireland but it is thought to have been present since at least 2001, despite only being reported in 2008.

Mechanism of impact

Competition, Interaction with other invasive species, Other

Broad environment


Habitat description

Found in hedgerows, wooded land, grassland and cultivated areas (Churchfield, 2008).

Species group


Native region


Similar species

Pygmy shrew (Sorex minutus)


World distribution(GBIF)

Irish distribution

Established - Widespread and expanding. Range estimated at 7,600km2 in 2013, with a rate of expansion of 0.5-14.1km/yr depending on landscape characteristics (McDevitt et al., 2014). 

Native distribution

Native range extends from central Germany to Iberia and into Northern Africa (Churchfield, 2008)

Temporal change

Date of first record category


Fifty year date category


Records submitted to Data Centre in 2024

The following map is interactive. If you would prefer to view it full screen then click here.

How can you help

Report any sightings to the National Biodiversity Data Centre.



Montgomery, W.I., Lundy, M.G. and Reid, N., (2012). ‘Invasional meltdown’: evidence for unexpected consequences and cumulative impacts of multispecies invasions. Biological Invasions, 14(6), pp.1111-1125.

Churchfield, S. (2008) Greater white-toothed shrew Crocidura russula In: Mammals of the British Isles: Handbook, 4th Edition. (Eds) Harris, S. & Yalden, D.W. The Mammal Society, Southampton. 

McDevitt, A.D., Montgomery, W.I., Tosh, D.G., Lusby, J., Reid, N., White, T.A., McDevitt, C.D., O'Halloran, J., Searle, J.B. and Yearsley, J.M., (2014). Invading and expanding: range dynamics and ecological consequences of the greater white-toothed shrew (Crocidura russula) invasion in Ireland.  2014 Jun 23;9(6):e100403. doi: 10.1371/journal.pone.0100403. eCollection 2014

 Invading and expanding: range dynamics and ecological consequences of the greater white-toothed shrew (Crocidura russula) invasion in Ireland.

Atlas of Irish Mammals

IUCN Red List of Threatened Species