Myosorex Cafer – Dark-Footed Forest Shrew

Myosorex cafer – Dark-footed Forest Shrew and Mozambique population are considered a new species (M. meesteri) and the Limpopo lineage was tentatively assigned to M. tenius based on small cranial size. A detailed molecular and morphological analysis of the latter assignment is underway. Assessment Rationale This newly recognised endemic species is a forest habitat specialist, occurring primarily in moist afromontane forest. The current estimated area of occupancy (AOO) of forest habitat, based on remaining natural habitat in 2014, is 1,263 km2. Climate modelling work shows that forest James Harvey habitat and thus AOO will be reduced by 37–48% by 2050 (since 1975). If we assume a linear rate of loss, 4.9–6.4% of suitable available habitat will be lost in the next 10 Regional Red List status (2016) Vulnerable years. This model is corroborated by recent land cover B2ab(i,ii,iii,iv)*† analysis in KwaZulu-Natal which showed there was a National Red List status (2004) Data Deficient 19.7% loss of natural habitat in from 1994 to 2011, with an average loss of 1.2% per year. Although the niche models Reasons for change Non-genuine change: predict a shift towards the coast as the climate changes, Taxonomy, newly split there are very few natural areas left as coastal Global Red List status (2016) Least Concern development has proceeded rapidly (between 2000 and 2013, there has been a 5.6% and 1.1% rate of urban and TOPS listing (NEMBA) None rural expansion in KwaZulu-Natal Province respectively) CITES listing None and thus this represents an outright loss of AOO. Furthermore, remaining forest patches are fragmented Endemic Yes and the species is suspected to have poor dispersal rates. *Watch-list Data †Watch-list Threat Thus, we list this species as Vulnerable B2ab(i,ii,iii,iv) as it has a restricted and severely fragmented AOO, with an Although once considered to occur in Limpopo inferred and projected ongoing decline in both outright Province, Zimbabwe and Mozambique, recent habitat, habitat quality (if moist conditions deteriorate) and morphological and genetic evidence indicates forest patches (construed as subpopulations) from climate that M. cafer is endemic to the KwaZulu-Natal and change, residential and industrial expansion and edge Eastern Cape provinces of South Africa (Willows- effects. Key interventions include protected area Munro 2008; Taylor et al. 2013). expansion of forest habitats, including the creation of corridors between patches and across elevational gradients to facilitate gene flow and allow adaptation to climate change, as well as the enforcement of regulations Taxonomy restricting disturbance to protected forests. Myosorex cafer (Sundevall 1846) ANIMALIA - CHORDATA - MAMMALIA - EULIPOTYPHLA - Distribution SORICIDAE - Myosorex - cafer Although previously thought to exist in South Africa, Mozambique and Zimbabwe, recent molecular work has Common names: Dark-footed Forest Shrew (English), confirmed it as endemic to the assessment region Donkerpoortbosskeerbek (Afrikaans) (Willows-Munro 2008; Taylor et al. 2013). It is now thought Taxonomic status: Species not to occur within Limpopo or Mpumalanga provinces, where these specimens may instead refer Mysorex cf. Taxonomic notes: Meester et al. (1986) recognised the tenuis (Taylor et al. 2013). However, further molecular and subspecies M. c. cafer and M. c. sclateri but biochemical taxonomic work of existing museum specimens is and morphological data suggested a rise to full species necessary to fully delineate the two species. Similarly, it is status for both (Maddalena & Bronner 1992; Kearney not certain whether Dark-footed Forest Shrews occur in 1993). Isolated populations in the highlands of Zimbabwe Swaziland (Table 1). They occur in KwaZulu-Natal and and Mozambique; and north-eastern Limpopo have been Eastern Cape provinces (Figure 1), as far west as the previously assigned to M. cafer (Friedmann & Daly 2004). Amathole Forest at Hogsback (Skinner & Chimimba Within the M. cafer complex, Willows-Munro (2008) and 2005). They are sympatric in some areas with the more Taylor et al. (2013), using a combination of molecular and widespread M. varius. They are restricted to moist morphological characters, demonstrated considerable evergreen Afromontane (above 1,000 m asl) and lineage diversification. Myosorex sclateri and M. cafer temperate forests, which are highly fragmented within the were split in 2008 (Willows-Munro 2008). The Zimbabwe assessment region. The estimated extent of occurrence is Recommended citation: Willows-Munro S, Baxter R, Taylor PJ. 2016. A conservation assessment of Myosorex cafer. In Child MF, Roxburgh L, Do Linh San E, Raimondo D, Davies-Mostert HT, editors. The Red List of Mammals of South Africa, Swaziland and Lesotho. South African National Biodiversity Institute and Endangered Wildlife Trust, South Africa. The Red List of Mammals of South Africa, Lesotho and Swaziland Myosorex cafer | 1 Figure 1. Distribution records for Dark-footed Forest Shrew (Myosorex cafer) within the assessment region Table 1. Countries of occurrence within southern Africa Number of mature individuals in largest subpopulation: Unknown Country Presence Origin Number of subpopulations: Unknown, but may Botswana Absent - correspond to discrete forest patches. Lesotho Absent - Severely fragmented: Yes Mozambique Absent - Namibia Absent - Habitats and Ecology South Africa Extant Native Dark-footed Forest Shrews are restricted to moist, densely Swaziland Presence uncertain Native vegetated forests and grasslands. In KwaZulu-Natal Zimbabwe Absent - Province, it occurs almost exclusively in Afromontane (mistbelt), scarp and coastal forests (Taylor 1998), while in the Eastern Cape Province they can be the dominant 59,384 km2. The current estimated area of occupancy small mammal species in Afromontane forest (Baxter & (AOO) of forest habitat, based on remaining natural Dippenaar 2013b). In captivity, they are predominantly habitat in 2014, is 1,263 km2. nocturnal (Baxter et al. 1979), but, although almost entirely nocturnal in summer, are trapped during the day during winter (R. Baxter, unpubl. data). In the Amathole Forest, Population they have been observed to forage in the soil substrate, This species generally occurs at densities of around 10–30 presumably searching for soil invertebrates (R. Baxter individuals / 0.01 km2 in suitable habitat (R. Baxter, pers. obs.). unpubl. data). Extrapolating this density estimate across Ecosystem and cultural services: Candidate for flagship its estimated area of occupancy yields a population size of species in forest biodiversity stewardship schemes. Both 1,263,000–3,789,000 individuals. It is more abundant in the Barn Owl (Tyto alba) and the Grass Owl (Tyto damp microhabitats and tends to be more common in capensis) are known to prey on this species (Skinner & forests while M. varius dominates in grasslands (Baxter & Chimimba 2005). Dippenaar 2013a). Current population trend: Declining. Inferred from Use and Trade ongoing forest habitat loss. There is no known subsistence or commercial use of this Continuing decline in mature individuals: Unknown species. Number of mature individuals in population: 1,263,000 Myosorex cafer | 2 The Red List of Mammals of South Africa, Lesotho and Swaziland Table 2. Threats to the Dark-footed Forest Shrew (Myosorex cafer) ranked in order of severity with corresponding evidence (based on IUCN threat categories, with regional context) Evidence in the Scale of Rank Threat description Data quality Current trend scientific literature study 1 7.2 Dams & Water Management/Use: Driver et al. 2012 Indirect (land National 65% of wetland ecosystem types wetland loss through drainage/water cover change threatened. abstraction during agricultural, industrial from remote and urban expansion. sensing) 2 2.3.2 Small-holder Grazing, Ranching or Bowland & Perrin Empirical Local Possibly increasing with human Farming: wetland and grassland 1989 settlement expansion and degradation through overgrazing intensification of wildlife farming. (removal of ground cover). Driver et al. 2012 Indirect National 45% of remaining wetland area exists in a heavily modified condition. 3 7.1.2 Suppression in Fire Frequency/ - Anecdotal - - Intensity: human expansion around forests has decreased natural fire frequency. Current stress 1.2 Ecosystem Degradation: altered fire regime leading to bush encroachment (including alien vegetation invasion) and thus loss of moist grasslands. 4 11.1 Habitat Shifting & Alteration: moist Taylor et al. 2016 Simulation National Increasing: a potential reduction microhabitats lost from Afromontane in area of occupancy of 27–33% forest cover reduction and aridification. between 1975 and 2050. 5 1.1 Housing & Urban Areas: forest habitat GeoTerraImage Indirect (land Regional Continuing. Area of urban lost to residential and commercial 2015 cover change expansion has increased by development. Current stress 1.3 Indirect from remote 5.6% and 6.3% for KwaZulu- Ecosystem Effects: fragmentation and sensing) Natal and Eastern Cape isolation of remaining forest patches with provinces, respectively, between limited dispersal between. 2000 and 2013. available. The fragmented nature of forest patches is likely Threats to exacerbate the effects of climate change. Habitat in The main threat to shrews is the loss or degradation of neighbouring areas is arid and unsuitable for this species moist, productive areas such as wetlands and rank and thus it would not be able to disperse to other areas if grasslands within suitable

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