SANBI

Rationale (Changed due to Same category and criteria)

Listed as Critically Endangered because its area of occupancy (AOO) is 7 km², its distribution is severely fragmented, and there is a continuing decline in its AOO, and in the extent and quality of its habitat.

Distribution

This species occurs only in the coastal lowlands (between 10–80 m Asl) in the south-western part of Western Cape Province, South Africa, where it formerly ranged from Cape Town east to the Agulhas Plain – with an extent of occurrence (EOO) of 1,399 km². However, it is now extinct on the Cape Flats near Cape Town, except for a cluster of breeding sites at Kenilworth Race course. Its eastern distribution is much more fragmented than is shown on the map (four subpopulations), since it occurs only in very isolated localities. Its AOO is 7 km² and its EOO is 1,559 km².

Decline

Over 50% of individuals are in isolated patches and the distances between subpopulations are considered to be too great for dispersal within one generation.

Habitat View more ecological information

Population trend

Trend

It occurs in high densities at breeding sites, which are few and far between. Historically this species was known from a greater extent in the western part of its range, with sites at Crawford, Lansdowne, Princess Vlei, Retreat, Ottery and Varkensvlei, but habitat degradation caused by development is believed to be responsible for their disappearance there (A. Rebelo pers. comm. August 2016). The spatial distribution of this species is now considered to be severely fragmented as over 50% of individuals are in isolated patches, and the distances between subpopulations are considered to be too great for dispersal within one generation. Due to ongoing decline in the extent and quality of habitat, the population is decreasing at the localities of Betty's Bay and Kleinmond (A. de Villiers pers. comm. July 2016).

Threats

It has a very restricted range in an area that is subject to the impacts of urbanization, agricultural expansion, the spread of alien vegetation (leading to an alteration in water quality and the drying out of breeding pools), and the drainage of breeding habitats. There has been a gradual decline in habitat quality in two subpopulations (Betty's Bay and Kleinmond), and invasive alien vegetation remains a threat to all subpopulations. Three of the four subpopulations in which it occurs are under constant pressure from development.

Uses and trade

There are no records of this species being utilized.

Conservation

Conservation Actions
Agulhas National Park is the only statutory protected area in which this species occurs, although it is also present in various other local authority and private nature reserves.

Conservation Needed
Additional habitat protection is needed in view of the species’ fragmented distribution.

Research Needed
As its name implies, it is a very small frog and this research can be challenging. However, high priority should be given to resolution of the taxonomic status of disjunct populations. A further priority is to continue with the systematic monitoring of breeding activity by estimating the number of calling frogs at the breeding sites for this species.

References

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 title = {Amphibians of Central and Southern Africa},
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 year = {2004}
}
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,@inbook{9773,
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,@article{13318,
 author = {Visser, J.},
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}
,]

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