EURING Newsletter - Volume 1, November
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
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
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.
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