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Tayler, P.B., Navarro, R.A., Wren- Sargent, M., Harrison, J.A. & Kieswetter, S.L. 1999. TOTAL CWAC Report. Coordinated waterbird counts in South Africa, 1992-97. Avian Demography Unit, University of Cape Town. 251 pp. ISBN 0-620-247134.
Available from Avian Demography Unit, University of Cape Town, Rondebosch 7701, South Africa.
This detailed publication summarises the results of co-ordinated waterbird counts in South Africa between 1992 and 1997. A huge amount of information (2,133,535 waterbirds counted on 1,216 site visits) has been collected through the series of 12 counts since the inception of the Coordinated Waterbird Counts in 1991.
The report provides the first substantive analysis of these data. The main part of the report summarises these data firstly through a series of 187 site accounts, followed by 135 species accounts.
There are accounts (of variable length) for the following waders - Rostratula benghalensis, Haematopus moquini, Charadrius hiaticula, C. marginatus, C. pallidus, C. pecuarius, C. tricollaris, Pluvialis squatarola, Vanellus armatus, V. albiceps, V. senegallus, V crassirostris, Arenaria interpres, Xenus cinereus, Actitis hypoleucos, Tringa ochropus, T. glareola, T. stagnatilis, T. nebularia, Calidris canutus, C. ferruginea, C. minuta, C. alba, Philomachus pugnax, Gallinago nigripennis, Limosa lapponica, Numenius arquata, N. phaeopus, Recurvirostra avosetta, Himantopus moquini, Burhinus vermiculatus, Glareola pratincola, and Glareola nordmanni.
The CWAC scheme has organised counts of each participating wetland twice a year, in summer and winter. Few sites have participated since the scheme's inception, but most sites have been counted up to six times in each season, as the scheme has developed coverage. For each site, standard presentations describe the site and its location, and summarise the mean and maximum counts in each of the two seasons (highlighting when these counts exceed 1% and 0.5% thresholds of international importance).
For sites with large numbers of species and which have been counted regularly, trend graphs present annual changes in observed numbers for key species over the period covered.
Each species account similarly summarises the data, and gives listings of mean and maximum numbers at `top' sites at which the species has been observed, as well as mapping these sites against a distributional base map taken from the Southern African Atlas.
Context is provided by additional introductory chapters on the significance of South Africa's wetlands for birds as well as a general overview of results. This latter chapter summarises many of the threats faced by count sites, as well as providing, necessarily limited, interpretation of data for some of the main waterbird species.
The scheme organisers, participants and sponsors are all to be congratulated on their respective contributions to the creation of this very impressive report Ä a veritable mine of useful data and information. The report just scratches the surface of the potential analyses of these data.
For wader monitoring junkies this report is a must. There is frustration, however, at the glimmerings of interesting stories that are just emerging from the data. The full development of these will only be possible as further counts are made. The greatest utility of the scheme must, however, be to underpin efforts to highlight the conservation importance of these wetlands. Counts from CWAC will be crucial to highlight the importance of these sites in their national and international contexts.
Keep CWACing!
David Stroud
Wader Study Group Bulletin, Vol. 93, Dec. 2000, p. 27.
CWAC is a joint project of the Animal Demography Unit (Department of Zoology, University of Cape Town)
and the South African National Biodiversity Institute