Man and Birds. R. K. Murton
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adornment of their ladies with feathers was another excuse for slaughtering wild birds. Quite apart from a scandalous trade in ostrich and egret plumes, a host of seabirds were massacred within the British Isles. Kittiwake wings were in demand for the millinery trade and a large industry existed at Clovelly in Devon and elsewhere; 9,000 are supposed to have been killed on Lundy in one fortnight. Coulson (1963) gives many other examples and relates how the species was also shot for sport and food, resulting in a decline from which it did not recover until the early decades of the twentieth century.
It is against the background of serious over-exploitation that the increase of a very wide range of seabirds in the twentieth century must be viewed and several examples will appear in later chapters – the great crested grebe (see here), kittiwake (see here), oystercatcher (see here). The eider perhaps should also be mentioned. One hundred years ago it was confined to the islands on the west coast of Scotland, and at one mainland site in East Lothian and in the Farne Islands. From this very restricted range it had spread to a wider range in coastal Scotland and to the Shetland and Orkney Islands by about 1890, and it became common by 1922. The bird has always been subject to intensive cropping both for its eggs and its down. While its down could be collected from the nest after the eggs have hatched, in the majority of cases the eggs and down have been lifted together, repeat layings often being harvested as well. On the Farne Islands the eider has always received a measure of protection owing to its association with St Cuthbert, but as long ago as 1397 the Bursar’s roll of the Monastery of Durham, which contained the Shrine of Cuthbert, mentions the use of eider-down for stuffing and cushions. Several colonies in Scotland and the Farne Islands were reduced during the 1939–45 war when the birds were collected for food, but these have recovered. In addition, Tavener has documented a marked post-war rise in numbers of non-breeders round the British coast, associated with an increase in the Dutch population, and also increases in other parts of Europe and North America, all apparently resulting from protection. There has, however, been little southward extension of the bird’s breeding range in Britain in the past 20 years. More recent studies by Dr H. Milne on the Sands of Forvie Nature Reserve, Aberdeenshire, showed that local numbers increased from about 3,000 birds in 1961–3 to around 5,000 during 1964–7 and that most of this increase resulted from a particularly good breeding season in 1963. Thus home-production rather than immigration apparently accounts for eider increases in Britain at least.
The excesses of the late nineteenth century roused the passions of a few men, and probably more women of suffragette spirit, and their campaigning led to the first Seabirds Preservation Act of 1869, hopelessly inadequate in its conception but a step in the right direction, to be followed by the Protection Acts of 1880–96. This same climate of moral indignation also led to the formation of the Society (later Royal Society) for the Protection of Birds in 1891. The Society went from strength to strength in the vanguard of the more enlightened attitude to birds characteristic of the start of the present century, doing immense good for ornithology, albeit sometimes for the wrong reasons. Today, the R.S.P.B. stands in the forefront of a scientific and imaginative approach to bird conservation.
With the outbreak of the First World War a new and widespread appreciation of birds was apparent. Birds were still used, but in an atmosphere of greater affection and regard. Canaries are about fifteen times more sensitive to poisonous gases than man, and they were accordingly kept in cages in the trenches to give advance warning of a gas attack, just as coal miners had used them in the mines. Soldiers enjoyed their companionship, and singing birds also were extensively used in ambulance trains. As pigeons had relayed the conquest of Gaul to Rome and had brought the first news of Napoleon’s defeat at Waterloo to England, so they were put to extensive use in the war, old converted London buses being used as mobile pigeon lofts. In the Second World War, pigeons were again used extensively; for example, the underground movement in France employed them to send back messages to England. German gunners tried to shoot these birds down as they crossed the Brittany cliffs, and in Britain the authorities attempted to exterminate our south coast peregrines, for fear that they too might be successful in intercepting some vital message. The following appeared in The Times on 19 August, 1943:
A pigeon, released by a bomber crew from their rubber dinghy, has recently been responsible for their rescue in the Mediterranean. … Realizing that something had gone wrong when there was no response to their first S.O.S., they had released their carrier pigeon from its container. As soon as the message it carried had been deciphered, an air-sea rescue launch put out, and the airmen were safely rescued.
In contrast with a report for 26 September, 1969:
‘In what was called “the craziest strike of all”, 44 men went on strike for half a day at the giant pressed steel Fisher Body plant in Swindon because of low-flying pigeons. The dispute was the latest of a series of labour stoppages which is costing Britain’s car industry the loss of millions of pounds in exports. The workers who walked out were those who were caught in the crossfire of the “feeders”, men who have been scattering bread crumbs and other bits of food to encourage the pigeons, and the “whangers”, other workers who have been throwing nuts and bolts and other missiles to scare the birds away. “We were fed up with either being hit by nuts and bolts aimed by the whangers, or strafed by the pigeons diving for food,” a press operator said. Meanwhile, a works management committee has asked the “whangers” to stop throwing missiles and the “feeders” to eat their sandwiches themselves.’
Some of the major developments in the relationships between men and birds since these years have been very briefly mentioned in the preface, but much more could be added for which there is no space. It would be pertinent to follow the growth of pet-keeping and other manifestations of an increasing public interest in living things. Similarly, we might examine the post-war boom in bird watching and the significance of such discoveries as the number of rare birds visiting sewage farms; the stampede to such sites was like an ornithological ‘gold rush’ once the initial discoveries at Nottingham were disclosed (Staton 1943). Has this widespread interest in wild life come too late?
The main hazards to birds today arise from the increasing pollution of the environment with the waste resulting from the sheer numbers of man; ironically man has become an indirect threat to the survival of wild life just when he seems to have learned to appreciate it. Mellanby has recently dealt with the pollution problem so admirably that I shall not attempt more than a passing reference here. But this should not detract from the severity of problems about which new facts emerge almost daily. For instance, we are still treading extremely cautiously so far as certain persistent agricultural chemicals are concerned. When the threat to wild life from organochlorine insecticides became really apparent in 1960–1, there was all manner of special pleading; agriculturalists claimed that food production must be the over-riding concern, manufacturers of chemicals naturally enough belittled the hazards to birds, bird protectionists made exaggerated claims, and Rachel Carson did the public at large a service with her deliberately biased book. In the years that have followed the initial hysteria, good sense has prevailed. Research has got under way and is producing facts where before there was only conjecture. When bird watchers first pointed out that birds of prey were breaking and eating their eggs and that this seemed to be associated with the decline in numbers associated with toxic chemicals, their suggestion was greeted with scepticism by many people. Now, a careful study by Ratcliffe has suggested some answers, for he has demonstrated that there has been a decline in egg-shell thickness in the peregrine, sparrowhawk and golden eagle since about 1950, and this explains why eggs are broken more readily and are subsequently eaten by the parent birds. Thus, of 109 peregrine eyries examined between 1904–50 there were only three instances of egg breakage, compared with 47 in 168 eyries observed between 1951–66. Egg-breakage, decrease in egg-shell weight, status of the breeding population and exposure to persistent pesticides are correlated, and it would be unreasonable to suppose that there is no causal connection, even if the exact factors and mechanisms involved remain to be elucidated. Calcium metabolism in birds is controlled by oestrogen and parathyroid hormone, and there is evidence that pp D.D.T. will interfere with oestrogen-based mechanisms in the Bengalese finch (Jefferies 1967).
Pollution of the environment by persistent, poisonous chemicals, is the most obvious problem, firstly because small residues can be accumulated