Shetland mouse-ear (Cerastium nigrescens)
| Kingdom | Plantae |
|---|---|
| Phylum | Anthophyta |
| Class | Magnoliopsida |
| Order | Caryophyllales |
| Family | Caryophyllaceae |
| Genus | Cerastium (1) |
| Size | Plant height: up to 5 cm (2) Leaf length: 4 – 7 mm (2). |
Classified as Vulnerable in Britain and receives general protection under the Wildlife and Countryside Act, 1981 (3).
Shetland mouse ear is endemic to Shetland (it is found no-where else in the world) (2). It is a diminutive tufted herb (4), with densely hair-covered stems and leaves (2). It was once thought to be a subspecies of the related species Arctic mouse-ear (Cerastium arcticum), but it has since been given full species status. It differs to Arctic mouse-ear in that its leaves are elliptic in shape and dark green in colour with a deep purplish tinge (5).
Found on two sites on the island of Unst, Shetland (4) (5), one of which is in the Keen of Hamar National Nature Reserve (3). Although numbers of the plant fluctuate from year to year, the overall distribution has not changed and the long-term population trend is apparently stable (4).
Inhabits extremely exposed debris areas of shattered serpentine rocks that are very sparsely vegetated. This species has been found at altitudes of only 80 m, yet the habitat in which it lives is very similar to montane habitats (3).
Little is known of the ecology of this perennial species (4).
Part of the Keen of Hamar site was destroyed in 1967 as a result of agricultural improvement. Other areas have suffered as a result of livestock grazing and the resulting nutrient enrichment of the site. Mining has also been a problem (3).
The UK Biodiversity Action Plan (UK BAP) lists Shetland mouse-ear as a priority species. The Species Action Plan produced to coordinate conservation efforts targeted at this plant aims to expand the current populations (3). Researchers have already introduced the species to another suitable site on Unst. Furthermore, the Keen of Hamar is a National Nature Reserve, and the other site that supports Shetland mouse-ear is a Site of Special Scientific Interest (SSSI), so both areas benefit from a level of protection; grazing animals have already been excluded from the sites (3). It is hoped that with continued conservation efforts, the future of this vulnerable endemic mouse-ear species will be secured.
The UK BAP Species Action Plan for Shetland mouse-ear is available from:
http://www.ukbap.org.uk
This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact: arkive@wildscreen.org.uk
- Endemic: a species or taxonomic group that is only found in one particular country or geographic area.
- Perennial: plants that live for at least three seasons; after an initial period they produce flowers once a year.
- Subspecies: a population usually restricted to a geographical area that differs from other populations of the same species, but not to the extent of being classified as a separate species.
- National Biodiversity Network Species Dictionary (September 2003): http://www.nhm.ac.uk/nbn/
- Clapham, A.R., Tutin, T.G. & Moore, D.M. (1987) Flora of the British Isles: 3rd Edition. Cambridge University Press, Cambridge.
- UK BAP Species Action Plan (October 2003): http://www.ukbap.org.uk
- Preston, C.D., Pearman, D.A. & Dines, T.D. (2002) New Atlas of the British and Irish Flora. Oxford University Press, Oxford.
- Stace, C. (1991) The New Flora of the British Isles Cambridge University Press, Cambridge.