Family Bufonidae

Bufo angusticeps Smith, 1848

Cape Sand Toad, Sand Toad, Yellow-footed Toad, Sandskurwepadda (A)

By M. Cunningham

Currently accepted name: Vandijkophrynus angusticeps
Red listing status: Least Concern



Photo by Hardaker T. & , 2012. URL: FrogMAP: 393

Distribution

B. angusticeps is endemic to the Fynbos Biome, within which it is widespread, extending from near Humansdorp (3424BA) in the east, and along the coastal flats and Cape fold mountains to Nieuwoudtville (3119AC) in the west. Most quarter-degree grid cell records (almost 95%) are located in the Western Cape Province. Within this area, the species occurs in two very distinct environments, namely coastal flats and rocky montane areas.

Most records are from the sandy coastal flats between Witsand (3420BD), at the mouth of the Breede River, and Vredenburg (3217DD) near the Berg River mouth. B. angusticeps is rarely encountered in the eastern part of its distribution, probably partly due to the limited area of coastal sand flats along the Garden Route between Mossel Bay and the Tsitsikamma River mouth. More surveys are needed, however, in the extensive coastal sand flats of the Stilbaai area, between the Breede and Gouritz rivers (3421AC–3421BD).

Montane records of this species are from scattered sites high in the Cape fold mountains, such as around 1500 m in the Swartberg Mountains (3322AC; Branch 1990; 3321BD new atlas data) and near the summit of Matroosberg (3319BD; Branch 1990). Smith (1848) described the type locality as “the interior of Southern Africa” and “in localities far apart”, which is barely more accurate than specific.

B. angusticeps is part of the Angusticeps Division of Bufo (sensu Poynton 1996), an extremely closely related and morphologically confusing group of toads endemic to southern Africa that also includes B. gariepensis gariepensis, B. g. nubicolus, B. inyangae, B. robinsoni and B. amatolicus (Cunningham and Cherry 2000). Most of these taxa are geographically variable and at some sites it is difficult to assign individuals to a particular species.

Beyond the first range of Cape fold mountains, in the Little Karoo, Bokkeveld and ranges bordering the Great Karoo, the distribution of B. angusticeps overlaps that of B. gariepensis, although these species are rarely found in true sympatry and some shared locations may be based on incorrect identifications. Boycott (1988d) commented that the small toads from mountain fynbos in the Kammanassieberg (3322DB) were similar to B. amatolicus, although these are well outside the range of that species and should probably be considered a montane variant of B. angusticeps.

In the west, B. angusticeps is distributed across the Olifants River, overlapping the ranges of both B. gariepensis and B. robinsoni in the vicinity of Vanrhynsdorp. In this area, B. angusticeps appears to be displaced from the lowlands and is only found on the Bokkeveld escarpment and Gifberg/Matsikamma Mountain at the northwestern limit of the Cape fold mountains (3118DC; new atlas data). Poynton (1964) suggested that specimens collected in Namaqualand, between latitudes 30–31°S, are intergrades between taxa. Clearly more research is needed on morphology, colouration and genetic variation within this group, and this will require extensive and systematic sampling across the entire distribution of the Angusticeps Division, including montane populations and contact zones between taxa. Typical individuals of B. angusticeps are distinguished from other species in the Angusticeps Division by their unspotted white ventrum and bright yellow flush over the dorsal surfaces of their feet. However, these characters may be absent in certain areas, making identification difficult.

The atlas data are reasonably reliable but incomplete.

Habitat

B. angusticeps generally inhabit sandy soils in areas of high winter rainfall in the Fynbos Biome. Breeding occurs in shallow temporary pools in seasonally flooded fynbos or renosterveld vegetation types. In some areas, breeding sites may be in ploughed and planted fields, such as in the Swartland around Vredenburg (3217DD), and near Moorreesburg (3318AB) where this species co-occurs with Cacosternum capense on clay soils. B. angusticeps is not commonly seen outside the breeding season, although in montane sites individuals have been found sheltering under rocks (Branch 1990). The type series was “procured at different seasons of the year . . . among decaying leaves in districts coated with underwood” (Smith 1848).

Life history

Breeding occurs in winter, May–September, after heavy rains have saturated the soil and created pools that last for many weeks. On nights after such rains large numbers of B. angusticeps may emerge from their refuges and move to breeding sites. Numerous individuals may be encountered on roads at this time, and may move considerable distances to reach breeding sites.

In comparison with the frenzied cacophony of most toad choruses, breeding aggregations of B. angusticeps are a subtle affair. Calling males are often sparsely distributed and, as with several species in the Angusticeps Division, such as B. amatolicus, calls are weak and intermittent. Males call from exposed sites near the water’s edge. Rose (1929) recorded 650–850 eggs in a clutch, relatively few for a toad, while Channing (2001) set the upper limit at 3000. Blair (1972) noted that species in the Angusticeps Division have exceptionally large testes. These characteristics suggest strong competition among males, and that B. angusticeps uses other modes of communication to locate and choose mates. A study of the mating system of this species would provide a very interesting comparison with other southern African toads.

Rose (1962) recorded insects and small snails as food items.

Conservation

The habitat of B. angusticeps is fragmented among large areas of coastal sand flats and montane isolates, and has declined in abundance due to development of the coastal flats and drainage of seasonally inundated wetlands. It has been estimated that these threats have resulted in a greater than 50% reduction in the abundance of B. angusticeps over the past century (Harrison et al. 2001). In the past 20 years, the species has virtually disappeared from sites where it was formerly abundant, such as Rondebosch Common in Cape Town (Rose 1929) and the Jan Marais Municipal Nature Reserve in Stellenbosch (E. van Dijk pers. comm.).

Nevertheless, this species still has a relatively large extent of occurrence and area of occupancy away from urban centres, and is present in large protected areas such as Kogelberg Biosphere Reserve (3419AC), De Hoop Nature Reserve (3420AD) and Cape Peninsula National Park (3418AD). Hence, B. angusticeps was assigned to the category Least Concern (Harrison et al. 2001; this publication). Its conservation status will require reassessment once the taxonomic status of inland and montane populations have been determined.

Current distribution map



Undated records;  pre-1996;  1996 to 2002;  2003 to present

Citation:

  • Web:
    FrogMAP. 2017. Bufo angusticeps Smith, 1848. Animal Demography Unit. Acceesed from http://frogmap.adu.org.za/?sp=290; on 2017-11-18 11:11:02.
  • Book:
    Minter L.R., Burger M., Harrison J.A., Braack H.H., Bishop P.J. & Kloepfer D. (eds). 2004. Atlas and Red Data book of the frogs of South Africa, Lesotho and Swaziland. SI/MAB Series no. 9. Smithsonian Institution, Washington, D.C. Published by the Smithsonian Institution and the Avian Demography Unit (now Animal Demography Unit).