Rationale (Changed due to Same category and criteria)

This endemic species remains listed as Least Concern in view of its wide (albeit fragmented) distribution within the Western and Eastern Cape, and because its habitat is largely inaccessible and unlikely to be extensively transformed. The estimated extent of occurrence is 150,917 km². There are no major threats expected to cause range-wide population decline. However, although around 76% of the Western Cape is still considered natural or near-natural, information from the Western Cape Nature Conservation Board indicates that there is a continuing decline in natural habitat from agricultural expansion, especially on lower- to mid-slope areas (below 1,000 m) from planted pastures and rooibos, wine and fruit cultivation, which may impact the species in the future as climate change makes higher elevation habitats more suitable for agriculture. Additionally, there may be localised losses of habitat quality due to the spread of invasive alien species, inappropriate fire regimes, and edge effects associated with agricultural and residential land-uses (for example, use of pesticides and predation from domestic pets). Although the species remains widespread and regularly encountered, proactive mitigation measures, including protected area expansion and habitat restoration, should be continued to counteract habitat loss. Protected area expansion to connect fragmented subpopulations, especially in the low-lying fynbos areas, would especially benefit this endemic species.

Distribution

This species is endemic to southwestern South Africa, largely restricted to the Fynbos Biome in the Western Cape Province (Mugo et al. 1995), and partially extending into the Northern and Eastern Cape provinces (Avery and Avery 2011). Their range may extend from the Olifants River in the west to the Knysna district and Plettenberg Bay in the east. They occur in a variety of habitats, including grasslands, fynbos and forests (Monadjem et al. 2010). The estimated extent of occurrence using all records is 150,917 km². Further field surveys are necessary to confirm current occupancy within its range.

Habitat View more ecological information

Population trend

Trend

Threats

The lower-lying areas of this species’ range are threatened by habitat loss and fragmentation as a result of urban and agricultural expansion (Pence 2014a), while the inaccessible montane portions of its range are unlikely to be extensively transformed. However, climate change may make higher elevations more suitable for agricultural expansion (see below) and thus represents an emerging threat.

The effects of global climate change on the endemic Fynbos Biome of South Africa, and its interaction with land transformation has been assessed by Midgely et al. (2003), who predict the potential range contraction and elimination of certain Proteaceae species. Climate change was predicted to have more of an impact on Proteaceae species than land transformation; as land transformation was considerably less prevalent in regions of higher altitude (Midgley et al. 2003). Additionally, altered fire regimes due to climate change and the expansion of invasive alien plant species may lead to habitat degradation and fragmentation, thus affecting the availability of shelter and forage resources for this species. The fynbos habitat is impacted in parts by invasive alien plants which, despite control efforts, are expanding (van Wilgen et al. 2012). Replacement of natural vegetation by non-indigenous species may reduce food resources and lead to altered fire regimes, which may become a threat if the fire return interval becomes so short that seeds preferred by the Verreaux’s Mouse cannot be produced.

Habitat is currently declining, in the lowland fynbos habitats. However, as 76% of the province remains natural or near-natural and the protected area network continues to expand (Pence 2014b), we suspect that habitat loss from agricultural expansion will only impact the species if higher-elevation areas are increasingly converted to crops, which may become likely as climate change makes such areas suitable. For example, climate change is projected to increase the suitability of upslope habitats for viticulture, increasing the footprint of winelands by 14% by 2050 (Hannah et al. 2013). Such trends in transformation of mid- and upper-slopes should be monitored.

Uses and trade

This species is not known to be traded or utilised in any form.

Conservation

This species is present within a number of protected areas of the assessment region, such as the West Coast National Park, De Hoop Nature Reserve and Vrolijkheid Nature Reserve. Although no specific conservation interventions are necessary, this species would benefit from protected area expansion, thus connecting lowland fynbos areas to patches of inaccessible montane habitat. Progress is being made in protected area expansion in the Western Cape, especially in Critical Biodiversity Areas (CBAs) (Pence 2014b). Stewardship on private lands may be particularly promising. For example, the Biodiversity Stewardship Programme has added over 490 km² to the Western Cape’s formal protected area network since its launch in 2003, by entering into biodiversity agreements with private landowners (Maree et al. 2015). Such agreements should be enhanced through best practice management techniques for both viticulture and biodiversity, a new field dubbed vinecology, which is actively implemented in South Africa (reviewed in Viers et al. 2013).

Recommendations for land managers and practitioners:
It is critical that the fight to eradicate invasive alien plant species from our protected areas continues and that every effort be made to maintain the “natural” fire regime within the Fynbos Biome. Landowners should be incentivised to employ the Working for Water Programme (Department of Environmental Affairs) to restore habitats.

Research priorities:
1) Rate of future habitat loss in the Western Cape, especially in higher altitude areas due to climate change and viticultural expansion.

2) Estimating population size through density estimates and total natural habitat available. This would enable a threshold of habitat loss to be calculated below which the population is expected to be fewer than 10,000 mature individuals.
3) Effectiveness of invasive alien plant removal in increasing small mammal occurrence and abundance.
4)Effectiveness of implementing vinecology management on small mammals should be monitored and evaluated.
5) Research into how this species responds to fire frequency and the extent of dependence on nut-fruited plants and mammal-pollinated plants.

Encouraged citizen actions:
1) Report sightings on virtual museum platforms (for example, iSpot and MammalMAP), especially outside protected areas.
2) The consistent clearance of invasive alien plant species across areas of the Cape Floristic Region reduces habitat degradation and water loss for native biodiversity.
3) Plant indigenous vegetation in gardens and ensure corridors of natural vegetation remain to allow local movements.