Genetic studies indicate that the population on Gran Canaria in the Canary Islands (previously considered to be a separate species, Crocidura osorio) is conspecific with C. russula (Vogel et al. 2003), although differences in size, ecology, and behaviour (Hutterer et al. 1992) characterise it as a distinct island form.

European regional assessment: Least Concern (LC)
EU 27 regional assessment: Least Concern (LC)

This species is very widespread and common, with an extent of occurrence of 2,055,068 km². Evidence points towards a range expansion in Europe, and there are no serious threats, hence it is listed as Least Concern for both Europe and the EU 27 Member States.

The White-toothed Shrew (Crocidura russula) is found in southern and western Europe (including some Atlantic and Mediterranean islands). The population on Gran Canaria in the Canary Islands (previously considered to be a separate species, Crocidura osorio) seems to have been introduced from Spain (Vogel et al. 2003). It has also been recently introduced to southern Ireland, Great Britain and Norway where it is considered invasive (Gargan et al. 2016, Bond et al. 2022, van der Kooij and Nyfors 2023). It typically occurs from sea level to 1,200 m, but has also been found as high as 2,000 m in Mediterranean landscapes (Palomo et al. 2007).

Outside of the assessment region, it also occurs in North Africa, in Morocco and western Algeria (Aulagnier and Vogel 2013, Nicolas et al. 2014).

Population size is unknown, although the species is generally widespread and fairly common within its range. Several studies suggest that populations are growing. In Germany, it is stable and expanding in some parts, although it is not known if this is natural or the result of accidental human transportation (Kraft 2000). In the Netherlands, occupancy at 1 x 1 km sites increased between 1995 and 2012 (van Strien et al. 2015). It is probably the most common shrew where it occurs in Spain, and is often the dominant prey species in the Barn Owl (Tyto alba) diet in this region (Ramalhinho et al. 1999). The White-toothed Shrew can be found at similar levels of occupancy to that of abundant shrew species such as the Common Shrew (Sorex araneus) (van Strien et al. 2015, Talleraas 2021).

In the Mediterranean, it occurs in a wide range of habitats including shrubland (maquis), open habitats, forest edges with abundant ground vegetation, cultivated fields, urban areas, gardens, farms, mountainous areas and land adjacent to rivers and streams (Palomo et al. 2007). It also favours old terraces with dry stone walls. Within open habitats such as burned sites, the White-toothed Shrew tends to be more abundant, with higher population growth rates (Torre et al. 2020). The Canary Islands population is found in remnant patches of the humid laurel forests in northern Gran Canaria and also in extensively managed farmlands. This population, along with the endemic Canary Shrew (C. canariensis), has a small litter size and lower metabolism than mainland shrews, possibly in response to living in a warm and/or variable environment. In northern Europe and at higher altitudes, it is predominantly synanthropic, living in close proximity to humans, houses and gardens (Ramalhinho et al. 1999). Its gestation length is 27-30 days, and litter size typically two to six (Palomo et al. 2007). Breeding can take place between spring and autumn, during which the White-toothed Shrew forms monogamous and territorial pairs. In winter seasons, it will nest communally in mixed-sex groups (Cantoni and Vogel 1989). It primarily feeds on myriapods, isopods, arachnids, gastropods and lepidoptera larvae (Palomo et al. 2007).

Due to its synanthropic habits it may suffer from the exposure to pesticides and other toxic chemicals in the environment (Ramalhinho et al. 1999), but this is not thought to be a serious threat to the species at present.

This species is not utilised or traded.

It receives legal protection under the Bern Convention (Appendix III), and it occurs in numerous protected areas. The Canary Islands population is protected under Spanish law.