The descriptive text, below the map, is from the Cornish Red Data Book (2009). The map on this web page depicts the organisms distribution and shows the records made pre-2000 and those made since.
Range & Status
A very widespread distribution in Europe, Asia and Africa: this species occupies most of the Palaearctic to Korea but is absent from most of Spain, north-west France and Great Britain (Harris & Yalden, 2008). It is also present on some French offshore islands, on Jersey and Sark in the Channel Islands, and in the Isles of Scilly (where densities are greater than on Jersey and Sark). Absent from the rest of Britain and Ireland (Corbet & Harris, 1996). The Scilly Lesser White-toothed Shrew was recognised as a distinct subspecies ( Crocidura suaveolens cassiteridum ) on the basis of its darker colour. Subsequent evidence, however, suggests that this is invalid. Animals from the various Scilly Islands are more alike than those from Jersey or Sark: but from skull and tooth row length are
intermediate in size between the largest on Sark and the smallest on Jersey (Harris & Yalden, 2008).
On the Isles of Scilly Lesser White-toothed Shrew occurs on all but some of the smaller Islands: St. Mary' s, St. Martin' s, Tresco, Bryher, St. Agnes, Gugh, Samson, St. Helen' s, Annet, Great Ganilly, Great Innisvouls and Te\'e4n (Parslow, 2007), and especially common on St. Mary' s and Tresco (Temple, 1996). It is thought that this species was introduced to the Isles of Scilly during, or before, the Iron Age (Corbet & Harris, 1996). A total prebreeding population estimate of 14,000 is given by Harris et al . (1995), with a maximum of one per 30m\'b2 (Corbet & Harris, 1996). However, Temple (1996) estimated a mean current population of 158,000 individuals. Given this figure it is clearly under-recorded on the ERCCIS database, and it appears that many records exist from research work that needs to be located and captured for local analysis. Although the population on the Isles of Scilly is under no evident immediate danger, it probably qualifies for Red Data Book status in Great Britain, since island populations are vulnerable.
Habitat & Ecology
On the Isles of Scilly, Lesser White-toothed Shrew occurs amongst boulders, vegetation and rotting seaweed on the sea-shore, especially on sheltered boulder beaches near the high-tide line where it can retreat to terrestrial vegetation (Harris & Yalden, 2008). In other locations it is found in most habitats that provide enough cover: commonly found in tall vegetation which includes Bracken Pteridium aquilinum , hedgebank cover and woodland, as they can climb readily, and around houses, which they occasionally enter (Parslow, 2007). It feeds predominantly on sandhoppers (on the shore), the amphipod Arcitalitrus dorrieni , millipedes, adult and larval flies, adult and larval beetles, spiders and mites (Corbet & Harris, 1996; Cooper, 2006).
This species is well established: no threats to the population are apparent (Harris et al ., 1995).
The population should be monitored and ERCCIS could trace records of this species from past research work such as that by Temple (1996). This species is partially protected by the Wildlife and Countryside Act, Schedule 6; they can not be trapped without a licence and precautions must be taken to ensure they remain alive. Listed (long list) as a globally threatened/declining species (BSGR, 1995) and included in the Isles of Scilly Biodiversity Audit 2008.
I.J. Bennallick, S. Board, C.N. French, P.A. Gainey, C. Neil, R. Parslow, A. Spalding and P.E. Tompsett. eds. 2009. Red Data Book for Cornwall and the Isles of Scilly. 2nd Edition.Croceago Press.
The Cornish Red Data Book Project was led by the Cornwall and Isles of Scilly Federation for Biological Recorders (CISFBR). The full text and species accounts (minus the maps) are available on the CISFBR website.