Danish ornithologist Hans Mortensen (left) first fitted metal rings to birds, and ringing continues now in a very similar fashion (right), though on a far wider scale.
36 : Mortensen bird ring
1890
Danish ornithologist Hans Mortensen (left) first fitted metal rings to birds, and ringing continues now in a very similar fashion (right), though on a far wider scale.
Bird ringing, or banding as it is known in North America, has proved to be the best way to reveal the international wanderings of birds as they migrate, for more than a century providing much-needed information on behaviour and conservation needs as well as distribution.
Birds have been marked in various ways since Roman times, when documentation dated to around 218-201 BC shows that officers during the Punic Wars were already using trained crows to convey messages attached to threads. Medieval falconers attached small discs holding their seal to their birds, while Royal swans had their ownership denoted after about 1560 by a nick or ‘swan mark’ on the bill. The legendary John James Audubon (see pages 46–47) also proved in 1803 that his local Eastern Phoebes returned to their birthplace by attaching silver cords to their legs as chicks.
However, it fell to a Danish school teacher to pioneer ringing as a method of discovering more about the movements of birds. Hans Christian Cornelius Mortensen (1856-1941) trapped Starlings in nestboxes in 1890, using self-designed ‘snappers’ or pliers and fitting home-made and labelled aluminium rings onto the birds. He then graduated onto White Storks and ducks, species known to migrate and also accessible for trapping. The novelty of the idea led to many of his recoveries being reported by local newspapers.
Ornithologists were quick to cotton on, and in 1902 Paul Bartsch began the first organised banding scheme in North America, when he ringed more than 100 Black-crowned Night Herons for the Smithsonian Institution. Another American, Jack Miner, banded more than 20,000 Canada Geese between 1909 and 1939, quickly establishing the importance of collecting mass data when the rings were returned by hunters.
In Britain, two ringing schemes were ‘hatched’ in 1909, with one run by the fledgling journal British Birds (see pages 96-97), instigated by its editor Harry Forbes Witherby, and another at Aberdeen University, started by Arthur Landsborough Thomson. A third scheme, organised by Country Life magazine, also started at this time, but the rings were not uniquely numbered.
The Aberdeen scheme ended during the First World War, and in the 1930s, following the founding of the British Trust for Ornithology, the British Birds scheme was transferred to the BTO, which continues to administer the national ringing programme in Britain today.
Although recovery rates are very low, over time the sheer volume of birds ringed has led to truly revelatory discoveries. One of the first mysteries of migration to be solved was when a female Swallow, ringed as a chick in Staffordshire in May 1911 by John Masefield, a local solicitor, was recaptured (or ‘controlled’ in ringing parlance) in the Natal region of South Africa on 12 December the following year.
In 1919, von Lucanus reviewed more than 3,000 controls of 127 bird species, noting a pattern that indicated several distinct European ‘flyways’. The first migration atlas was published in 1931 by Schütz and Weigold, and presented data from more than 6,800 controls of 230 species, covering the whole of Europe, North Africa and the Middle East – the Western Palearctic.
In practical terms, the development of ringing pliers in the mid-1970s by Bert Axell, then warden of Dungeness RSPB reserve in Kent, was a quiet revolution. But the main innovation in ringing was in the early 1950s, when mist nets were first used, enabling the relatively harmless capture or recovery of small to medium-sized landbirds. They could be combined with fixed-frame Heligoland traps (see pages 192–193), while more robust cannon nets were soon introduced for bigger species like larger waders and gulls.
The increasing number of European ringing schemes was co-ordinated under the umbrella of the European Union for Bird Ringing (EURING) in the mid-1960s. Bird ringers undergo lengthy supervised training programmes administered by their national schemes before they can undertake the highly skilled business of extricating fragile, fluttering migrants from the mesh of nets and then weighing, measuring and ringing them – the welfare of the birds is always paramount.
Today, birds are ringed chiefly with numbered metal rings, and for specific studies sometimes with coloured plastic (‘darvic’) rings – often in combination with metal rings – though wing tags and bill saddles are still used for larger species such as raptors and ducks, and birds from captive breeding and reintroduction projects. Much data is still being gleaned on the nature of bird navigation, migration strategy, survival rates and estimations of population size, and the information from recoveries is an invaluable research and conservation tool.
Although the practice may eventually be superseded as radio and satellite transmission and tracking technology becomes cheaper and more widely available, the controlling and recovery of ringed birds continues to add vital detail to our knowledge of bird dispersal.