SANBI

Rationale (Changed due to Same category and criteria)

Listed as Endangered because its extent of occurrence is 1,371 km², its area of occupancy is estimated to be ca. 10 km², and both are experiencing a continuing decline, its distribution is restricted to four locations, and there is a continuing decline in the number of subpopulations and in the extent and quality of its habitat. Only about a quarter of the original Mistbelt grassland habitat remains, of which only 2.5% is protected.

Distribution

This species is restricted to a small area of mistbelt on the eastern escarpment of the KwaZulu-Natal Province (which includes the former enclave of Eastern Cape, now incorporated into KwaZulu-Natal), South Africa. Six fragmented and isolated subpopulations were known until 2004 (Minter et al. 2004). Recent surveys indicate that the species is extant at four of the six known sites, but it is possibly extinct at two of these sites (J. Harvey pers. comm. August 2009). In addition, it has been found to occur more extensively in Ngele Forest than previously known, at additional sites in the Ngele Mountain foothills, in the Mpur forestry area, and a new population within the Ixopo region (Roelton Dam) was also discovered (J. Harvey pers. comm. August 2009). Within the Mpur forestry area, it was recorded at several new sites (J. Harvey pers. comm. August 2009). In total, 12 subpopulations are now known, and these are aggregated in only four threat-defined locations. Surveys in 2015 and 2016 confirmed the species at Poortjie, Mpur, Ngele Forest and Qunu Falls (Trenor pers. comm. December 2015). It is known to occur between 1,020 and 1,720 m asl, and its total area of occupancy is estimated to be 12 km², while its extent of occurrence is 1,371 km².

Decline

Plantations are drying seepages.

The spatial distribution of this species is not considered to be severely fragmented as one subpopulation/location holds >50% of individuals; however, the distances between subpopulations is considered to be too great for dispersal within one generation.

Habitat View more ecological information

Population trend

Trend

Population trends are generally stable. Based on surveys conducted in 2003–2005, the global adult population size is estimated to lie between 2,495 and 3,350 individuals (J. Harvey pers. comm. August 2009). It is uncertain how many discrete subpopulations are involved, but for the purposes of this assessment we are provisionally considering twelve subpopulations, two of which may be extinct, based on the results of recent field work (J. Harvey pers. comm. August 2009). The largest single subpopulation would appear to occur in Ngele Forest, and while 'Poortje Forest' may also hold a large subpopulation, this still needs to be confirmed (J. Harvey pers. comm. August 2009). Although the Mpur forestry sites are separated, various sites may be connected as part of a larger subpopulation (J. Harvey pers. comm. August 2009). The spatial distribution of this species is not considered to be severely fragmented as one subpopulation/location holds >50% of individuals. However, other subpopulations are small and scattered and distances are considered to be too great for dispersal within one generation.

Threats

Large areas of the species’ grassland habitat have been afforested with, or have been invaded by, exotic vegetation (J. Tarrant pers. comm. October 2015). Currently very little conservation action takes place within this Key Biodiversity Area and the habitat type is recognized as Endangered (Scott-Shaw and Escott 2011). Additional threats include overgrazing, fragmentation, habitat damage due to harvest activities (J. Harvey pers. comm. 2006, 2009), and inappropriate fire and mowing regimes. The greatest threats are fires, invasive plants and habitat fragmentation resulting in population isolation (J. Harvey pers. comm. 2009). Forest populations appear to be less threatened given that their habitat patches are typically larger and not as exposed to many of the identified threats, including burning (J. Harvey pers. comm. 2006). Inappropriate use of agrochemicals for alien plant control could also potentially impact upon a population, although this has not been investigated (J. Harvey pers. comm. 2009). Climate change could also be a potential threat given predictions of loss of grassland biome and species range shifts and contractions due to changes in climatic conditions. This species has a small range and has less than half the population is distributed in subpopulations that are within a transformed land matrix and it is not likely that there is 'new' habitat to colonise, although this requires further investigation (J. Harvey pers. comm. 2009).

Uses and trade

There are no reports of this species being utilized.

Conservation

Conservation Actions
Although it occurs in the Ngele Forest Reserve, most of the habitat of this species is not protected. Recent surveys have found that the majority of populations occur on land belonging to two private forestry companies (J. Harvey pers. comm. 2006). These companies initially responded positively towards the species' conservation, and management guidelines were developed and provided to both companies, with one company implementing a monitoring programme for this species (J. Harvey pers. comm. 2006). However, no further monitoring efforts have taken place since. It is unknown whether these companies have implemented the suggested management recommendations (J. Harvey pers. comm. 2009). This is currently being followed-up through an EDGE Fellowship project (implemented by Endangered Wildlife Trust and North-West University) and management recommendations and monitoring plans are being reviewed with the current forestry management. One of the main sites, at Roelton Dam, has recently been proclaimed as a Protected Environment under the Biodiversity Stewardship Programme through Bird Life (J. Tarrant pers. comm. August 2016).

Conservation Needed
Improved protection and maintenance of the remaining habitat is a priority. Grassland sites are generally thought to be more vulnerable than forest sites and may therefore require more urgent safeguarding. Concerted research and development efforts in the area of captive breeding of this species are required to ensure against total extinction.

Research Needed
It is important to better understand this species' distribution. The natural history of this species and the relative impact of perceived threats need to be researched, and populations and habitat require monitoring. A current study is making use of automated monitoring equipment to establish density and spatial utilization.

References

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,]

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