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The Southern African Frog Atlas Project: progress, problems and prospects
J.A. Harrison and M. Burger
Avian Demography Unit, University of Cape Town,
Rondebosch 7701, South Africa
 If
ever reliable baseline distribution information were necessary for a group of
organisms, it is necessary for amphibians. Worldwide, disturbing reports of
population declines, mass mortalities and species extinctions of amphibians have
been accumulating for the last two decades (Wyman 1990; Wake 1991; Blaustein
& Wake 1995), so much so that the IUCN has established a Declining Amphibian
Populations Task Force (DAPTF). On a global scale, South Africa has a high
amphibian diversity, but 23 (21%) of the nation's frog species are Red Data
listed or, in other words, are either threatened with extinction or are likely
to become threatened in the near future (Siegfried 1989; Harrison et al. 2001).
Although the amphibian declines are not fully understood, and several factors
are implicated, there is no doubt that many populations and species are
experiencing extraordinary environmental pressures. At present in southern
Africa, the most important factor impacting on frog populations is almost
certainly habitat destruction, brought about by urban and agricultural sprawl,
wetland drainage and infilling, and pollution. Loss of frog populations is
likely to have negative effects on the functioning of ecosystems because adult
frogs are predators on invertebrates, and both adult frogs and tadpoles are
important prey for a variety of predators (Channing 1995).
There is an extreme lack of population-level information for African frogs -
SAFAP is a first step towards rectifying this situation. What is in critically
short supply is time. The rate of environmental destruction and change is such
that, within the next few years, biodiversity must be catalogued and mapped, and
effective conservation action plans put in place, or species will disappear
without our even noticing.
The Southern African Frog Atlas Project (SAFAP) was launched in November
1995. The project is co-ordinated from the Avian Demography Unit (ADU) at the
University of Cape Town, assisted by regional organisers in the various
provinces of South Africa, and in Lesotho and Swaziland.
Data are collected by volunteer members of the public and by professional
herpetologists. Data are submitted mainly in the form of audio recordings of
calling frogs. Being species specific and stereotyped, calls are a reliable form
of evidence on which to base identification of species (Harrison & Burger
1998). (Frogs are generally cryptic and hard to find, but even when in the hand,
they tend to be difficult to identify because of variability in skin colour,
markings and size.)
SAFAP aims to comprehensively cover all 110 species of frogs in South Africa,
Lesotho and Swaziland, on a quarter-degree (15'X15') grid (except in the arid
west where a half-degree grid is being used); there are 1650 grid cells to be
covered. Where reliable pre-atlas data are available, e.g. from the literature
and museum records, these are included in the SAFAP database; for some areas
this may provide a useful historical dimension.
To date (December 2001), c. 30 000 records, including c. 8000 pre-atlas
records, have been entered for 91% of the grid cells, although many of these
cells will require further visits to improve the depth of coverage, i.e., record
all species present. The greatest need is for more data from the arid western
parts of South Africa where rainfall is both scarce and unpredictable, but
where, nevertheless, several interesting species of frogs occur, and also from
inaccessible montane areas.
Acknowledgements
SAFAP has enjoyed the monetary backing of the South African Department of
Environmental Affairs and Tourism, WWF-SA, the Mazda Wildlife Fund, Total South
Africa, the Declining Amphibian Populations Task Force, the South African
National Research Foundation, and the Joan St. Ledger Lindburgh Charitable Trust
Reading
Blaustein A.R. & Wake D.B. 1995. The puzzle of declining amphibian
populations. Scientific American 1995: 56-61.
Channing A. & van Dijk D.E. 1995. Amphibia. In: Cowan, G.I. (Ed.) Wetlands
of South Africa, 193-206. Pretoria: Department of Environmental Affairs and
Tourism.
Harrison J.A. & Burger M. (eds) 1998. Frogs and frog atlasing in southern
Africa. ADU Guide 4, Avian Demography Unit, Cape Town.
Harrison J.A., Burger M., Minter L.R., De Villiers A.L., Baard E., Bishop P.
& Ellis, S. (eds) 2001. Conservation assessment and management plan for
southern African frogs. Final Report. IUCN/SSC Conservation Breeding Specialist
Group: Apple Valley, MN.
Siegfried W.R. 1989. Preservation of species in southern African nature
reserves. In: Huntley, B.J. (Ed.) Biotic diversity in southern Africa: concepts
and conservation. Oxford University Press, Cape Town.
Wake D.B. 1991. Declining amphibian populations. Science 253: 860.
Wyman R.L. 1990. What's happening to amphibians? Conservation Biology 4:
350-352.
Visit www.panda.org.za for more
information
Contact: James Harrison / Marius Burger
e-mail: batlas@maths.uct.ac.za
/ marius@maths.uct.ac.za
Sponsor's website:www.totalfinaelf.com
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