EURING Newsletter - Volume 1, November 1996

BIRD RINGING ACROSS THE WORLD

This section of the newsletter will be reserved to the introduction of bird ringing from an international perspective, trying to get a better knowledge of how ringing activities are organised and carried on also outside the EURING Schemes. This will undoubtedly offer new prospects and ideas to improve scientific bird ringing in Europe. In this first issue, Terry Oatley offers a brief introduction to SAFRING, the South African Ringing Scheme, with an overview of the organisation and the main projects carried on by our colleagues from the other hemisphere.

BIRD RINGING IN SOUTHERN AFRICA

by Terry B. Oatley

Southern Africa is the destination of many Palaearctic migrants which travel south to escape the winter months of the northern hemisphere. Some 75 Eurasian species commonly 'winter' in southern Africa, including several species of terns and many shorebirds (waders). Of the terrestrial birds the Barn Swallow Hirundo rustica is undoubtedly the most numerous migrant and the White Stork Ciconia ciconia one of the most noticeable. Other Eurasian species that winter in southern Africa in large numbers are Steppe Buzzards Buteo buteo vulpinus, Lesser Kestrels Falco naumanni, Willow Warblers Phylloscopus trochilus and European Sedge Warblers Acrocephalus schoenobaenus.

These migrants arrive in the southern hemisphere summer when most of the over 750 local Afrotropical species are breeding. Bird ringers in southern Africa therefore have an impressive diversity of species on which to target their activities.

The South African bird ringing scheme was initiated by the South African Ornithological society (SAOS) in l948. At that time the society's headquarters were in Pretoria, which was also the site of the National Zoological Gardens. "ZOO Pretoria" was adopted as the return address for the scheme's rings. Initially, much of the ringing was concentrated on colonially nesting waterbirds such as egrets and ibises; other colonially nesting species such as Cape Vultures Gyps coprotheres also received attention. Some of the provincial Nature Conservation authorities also initiated duck-ringing projects.

The annual ringing effort increased steadily, and by the late 1960's was outstripping the resources of the SAOS to adequately administer and finance it. In 1970, the Council for Scientific and Industrial Research convened a series of meetings which resulted in the formation of the South African Bird Ringing Unit (SAFRING). This Unit started operation in 1971 at the University of cape Town under the supervision of Director of the Percy FitzPatrick Institute of African Ornithology. It was funded by the provincial Nature Nature Conservation Departments whose ornithologists had become some of the main users of bird rings, primarily to facilitate research into waterfowl populations.

One of the initial goals of SAFRING was to computerise all documented recoveries or ringed birds and to initiate a databank of annual totals of species ringed. The University main frame computer was used for this purpose, and by 1981, a custom-written set of programs were in use to produce recovery printouts for ringers and finders, schedule summary printouts and species totals lists for ringers, regions, or time periods.

In December 1991, SAFRING became part of the Avian Demography Unit (ADU) of the Department of Statistical Sciences at the University of Cape Town. It is the first ringing scheme to find a home in a statistics department, and the move has proved very beneficial to the scheme. Problems of small data sets and the need to merge recoveries and recaptures to achieve adequate sample sizes have all received enthusiastic attention in the new environment. Additionally, bird ringing fits in very well with the other projects of the ADU (atlassing, waterbird census, population studies of large birds, etc.) and with its mission, which is to improve our understanding of avian population dynamics and to make a contribution to bird conservation by providing a scientific basis for conservation action. The ADU has a close association with the SAOS and focuses on large-scale demographic studies in which participation by amateurs is a vital element.

From the inception of the ringing scheme in 1948 to June 1995, over 1.57 million birds of 845 different species had been ringed in South Africa and the neighbouring countries of Namibia, Botswana, Zimbabwe, Mozambique, Malawi and Zambia, and on the islands of Mauritius and Sub-Antarctic islands of the Prince Edward group, Gough, and Tristam de Cunha. The numbers of birds ringed annually have fluctuated. Ringing effort peaked in the late 1960s at about 70,000 birds per annum, then dropped as low as 17,000 in the course of the following decade. Since the 1980s there has been a steady upward trend and over 71,000 birds were ringed in the 1994-1995 ringing year (the natural, austral ringing year is from July to June). During the 1980s there were generally between 90 and 110 ringers active in any year; this figure has increased to 130 ringers active in the 1994-1995 ringing year. Approximately 85% of registered ringers are amateurs. All ringers, both amateur and professional, have to pay for the rings they use.

The most frequently ringed bird in southern Africa is the Barn Swallow Hirundo rustica, with over 198,000 ringed by June 1995. Only two other species, the Cape Gannet Morus capensis and the Redbilled Quelea Quelea quelea have ringing totals exceeding 100,000 and another two, the Yellowbilled Duck Anas undulata and Masked Weaver Ploceus velatus, exceed 50,000 birds ringed.

Recovery rate of birds in southern Africa are lower than in most European countries; currently the overall recovery rate for South African rings is barely 1%. Recovery data sets are consequently meagre. Only the cape Gannet and the Jackass Penguin Spheniscus demersus have more than 1000 recoveries each; 28 other species have more than 100 recoveries each. 245 species boast less than 10 recoveries each, and for 471 species there are no recoveries at all. Many of the latter are small passerines and for such birds retrap records by ringers make up for the paucity or lack of recoveries and provide insight into survival rates.

Numbers of recoveries reported to SAFRING averaged 462 per year during the 1980s but have increased in recent years following increased ringing effort. The number of foreign rings reported each year is usually between 30 and 40, with Common Terns Sterna hirundo, Barn Swallows, White Storks and Sandwich Terns Sterna sandvicensis being the species most commonly reported.

Before extensive ringing of Barn Swallows started in southern Africa it was believed that most such swallows were from the British Isles because some 64% of all ring recoveries of this species involved BTO rings, with a scattering of rings from other schemes, mainly in western Europe. Once South African ringers learnt that Barn Swallows could be caught by the thousand at their reedbed roosts, a steady stream of recoveries were received from the former USSR, mainly between longitudes 21°E and 91°E. In fact some 80% of Barn Swallows which winter annually in southern Africa are evidently of Russian origin. Some of these have been controlled by Prof. Gavrilov whilst on spring migration through the Chok Pat Pass in Kazachstan. Further evidence that our Barn Swallows are mainly of Eurasian origin is reflected in the very few foreign-ringed controls caught during swallow-ringing activities in South Africa.

Wader ringing has also yielded interesting information on the origins of shorebirds visiting southern Africa. Several species have been recovered in Russia, with the Ruff Philomachus pugnax undertaking the longest migrations from the Gauteng Province of South Africa to 67°N and 15°E in Asia a great circle distance of 14174 kn.

Over 3500 Willow Warblers have been ringed in southern Africa but there have as yet been no recoveries from the northern hemisphere. The few European-ringed birds that have been recovered here have born either Helsinki or Stockholm rings; most Stockholm-ringed Willow Warbler recoveries have been made from farther north in the African continent, so it seems that those that have been recovered in South Africa have overshot their normal wintering area. All three races of the Willow Warbler visit southern Africa, with P. t. acredula perhaps the most common and P.t. yakutensis the least common.

There is obviously still much to be learned about the origins of Palaearctic migrants in southern Africa. Many birds captured and ringed here are retrapped in subsequent years, yielding information on fidelity to wintering site. But, as indicated above, the great majority of visiting migrants are unringed and it is apparent that most are coming here from the Asian side of Eurasia rather than from the European side.

Increased ringing of Barn Swallows in Europe may yield an increasing number of controls from South Africa because this is one species in which individuals from all over Europe appear to mix with the large populations from further east and fly around together on their winter holiday. We hope that renewed interest in ringing this species in Europe will bring many happy returns from South Africa.

T.B. Oatley is Ringing Co-ordinator of the SAFRING at the University of Cape Town.

Back to index of EURING Newsletter Volume 1