Ecological variables governing habitat suitability and the distribution of the endangered Juliana’s golden mole

Abstract

Juliana's golden mole (Neamblysomus julianae) occurs in three isolated populations in the northeastern parts of South Africa. This cryptic species is not evenly distributed throughout its restricted range and appears to have very specific habitat requirements. Its endangered status reflects the necessity for a conservation management programme, which to date has not been comprehensive. A primary hindrance to such initiatives has been the lack of information pertaining to its habitat requirements. We assessed various soil and vegetation parameters, at each population site, in areas where the animals were found to be present or absent. A multiple logistic regression model highlighted the importance of soil hardness (governed by soil particle size distribution), in combination with the cover provided by trees, as the two ecological factors that best explained habitat suitability for Juliana's golden mole at the three localities. An IndVal analysis failed to identify any plant species that could reliably act as an indicator of habitat suitability for this fossorial mammal. These results have important implications for the conservation of the species.

Predicting the potential distribution of an endangered cryptic subterranean mammal from few occurrence records

“…Despite occurring less than 15 km from the centre of South Africa's capital city, Pretoria, this species was only described in 1972 (Bronner & Bennett, 2005). Although recent studies have investigated certain aspects of its biology (Jackson et al, 2007(Jackson et al, , 2008(Jackson et al, , 2009, it is still relatively poorly known. The distribution range of the species is highly restricted.…”

“…This region is dominated by the savanna biome (Mucina & Rutherford, 2006). This area was chosen since the species is only known from savanna vegetation types (Jackson et al, 2008). Rainfall in the savanna biome is highly seasonal, resulting in wet summers and dry winters.…”

“…Occurrence records for the species were collected as part of a study on the habitat utilisation of the species (Jackson et al, 2008). The species was initially known only from the Bronberg Ridge and in the vicinity of Nylsvley Nature Reserve (Fig.…”

“…In this way species of conservation concern will gain a level of protection from threatening processes by being part of a network of conservation areas, whilst the biodiversity of the region will simultaneously be conserved. The endangered Juliana's golden mole (Neamblysomus julianae; Chrysochloridae) is a small (35 g), habitat-specific mammal that is particularly difficult to study due to its subterranean lifestyle (Jackson et al, 2008(Jackson et al, , 2009. Despite occurring less than 15 km from the centre of South Africa's capital city, Pretoria, this species was only described in 1972 (Bronner & Bennett, 2005).…”

“…Recently a thorough ecological assessment that specifically documented the species' habitat requirements was undertaken (Jackson et al, 2008). Using this information we aimed firstly to make use of ecological niche modelling to produce a potential distribution map for Juliana's golden mole that could be used to search for new populations.…”