Volume 67 Number 5 May 1974

A further review of the problem of 'escapes' M. D. England

INTRODUCTION During the twelve months ending 31st December 1972, 791,979 passed through the hands of the staff of the Royal Society for the Prevention of Cruelty to ' Hostel for Animals at London (Heathrow) Airport on arrival from abroad by plane. (Rather less than 100,000 of these were day-old chicks which are disregarded in this discussion.) It must be stressed that this was the number passing through the Hostel and not the total number of birds arriving at the airport, since only certain categories of consignments of animals are usually taken to the Hostel: most of those in transit and for which there may be considerable delay before a flight is scheduled for the continuance of their journey (some airlines will accept animals only for a further 'leg' of a journey if they have been checked at the Hostel); those which the addressee has specifically asked the RSPCA to look after; those which the airport staff have noticed contain an unusually high proportion of dead or dying birds or appear especially to need care; those not claimed within a reasonable time; and those in cages or boxes which are broken. A small proportion of birds in transit are transferred to an outgoing flight (especially if it be of the same air­ line as the flight by which they arrived), without passing through the Hostel. It should be mentioned in passing that, of those in tran­ sit which are destined for Germany, the Netherlands and Belgium, not a few will be re-exported back to this country. The majority of those addressed to recipients in Britain are taken direct to the freight sheds in the cargo centre and are collected by the addressee (or his agent), again without passing through RSPCA hands. Despite this,

177 178 The problem of 'escapes' 107,859 birds whose journeys terminated in Britain did pass through the Hostel in 1972, making the (unknown) total for Britain a matter for the mind to boggle at indeed. The grand total number of birds arriving at Heathrow Airport during that year is thus also at present unknown (although it is hoped that such figures may be made available in the not too distant future), but it can be seen that it is unlikely to be less than 1,000,000 and may be much greater. Although Heathrow handles the greater part of the traffic from overseas, other British airports must not be forgotten. For example, birds from the Far East intended for north-west England are usually sent via Manchester, this route often being via Germany and missing London, and the number is probably higher than it is usually thought to be. Nowadays few are sent by boat for any great distance, although some cross the English Channel in this way. If to this vast annual figure be added the unknown, but obviously huge, number of birds already in captivity in Britain and also those in captivity on the Continent (but see later), it is perhaps super­ fluous to add that there must be a risk of a not inconsiderable number escaping and surviving in the wild long enough to stand a chance of being seen by and causing confusion to British birdwatchers. It has been claimed (Blackwell 1972) that 'each week dozens escape', although no supporting evidence was given. The majority of British ornithologists probably have little know­ ledge of what has unfortunately but aptly been called 'the appalling trade', or indeed of aviculture, and thus find themselves in no position to assess the likelihood or otherwise of a 'rarity' having escaped from captivity. The purpose of this paper is to try in some measure to help by giving an outline of the species and sources of imported birds and some guidance on assessing particular cases of suspected escape. A paper on the same subject and covering much of the same ground has appeared before in this journal (Goodwin 1956). This has been at the same time a help and an embarrassment: a help for reasons which will be obvious to those familiar with it, an embarrassment because it has appeared presumptuous to attempt to 'paint the lily'. Hence the title of the present paper. It is inevitable that some information, especially that regarding sources and species, will be out of date even before publication, because the position changes continually as more exporting countries impose welcome restrictions and fresh sources open up as a result. Some species which were readily and cheaply obtainable a year or two ago are now never seen. Especially to those readers who already have some knowledge, much of the material may appear redundant or irrelevant, but it has been included in order to give background to the subject. 'Assisted passage' has not been dealt with because it is considered The problem of 'escapes' *79 to be outside the scope of this paper. However, the 'importation' of by members of the crew of Scandinavian whaling vessels must be mentioned. Although I have no personal experience of this and can find no published reference, it is frequently said that albatrosses and other similar birds are reared as pets while ships are in southern waters and, proving an embarrassment on arrival at the home port, are liberated to fend for themselves.

SOURCES AND DESTINATIONS The birds reaching Britain from abroad—whether for the British market, for re-export, or in transit—come from all over the world, but the greatest numbers come from Asia (Bangkok, Calcutta and Singapore providing immense numbers) and many parts of Africa. In parentheses it is fair to say, and a matter for congratulation, that some African countries take considerable trouble to prevent undesir­ able exploitation of their wild birds for export purposes. For example, Kenya allows trapping and export only under individual licence, with the result that birds from that country are rarely to be acquired in Britain through dealers or on the open market. Unfor­ tunately the neighbours of such enlightened countries are not always so careful (Boyle 1970) and the number of birds exported from Africa as a whole is very large indeed. Until recently South America was among the largest exporters, but during the autumn of 1973 a con­ siderable and very welcome (and it is to be hoped permanent) reduction took place as a result of some of the better-informed countries imposing restrictions. While in many countries trapping and export continue despite government measures or because officials turn a blind eye, it is greatly to be deplored that the contrary is true in (see Martin 1973). Here the government has recently published a report entitled Exportation from Thailand in ig62-yi (using the word 'animals' in its correct sense, to include birds). This is a horrifying document, as the following brief quotation will show: 'Wild animals make up one of the natural resources of the country which are of value to the economy ... In the past, Thailand has received millions of Baht income from the exportation of wild animals alone. Many species are in demand and therefore com­ mercial business dealing with wild animals seems to be a real promising one.' It is understood that a similar situation exists in North Korea. As mentioned above, no accurate figures are at present available of the total number which are intended for sale in Britain and of those destined for other countries, although the evidence suggests that the latter greatly exceed the former. While birds which are to remain in Britain obviously present a much greater escape risk, i8o The problem of 'escapes' those in transit cannot be ignored, because accidents can and do occur at airports. For example, at a British airport recently, the driver of a van containing crates of birds en route from plane to reception sheds noticed that a box was broken and that birds were escaping from it into the van. On going to report this he left the doors of the van open, with the result that later examination showed the box and the van to be almost empty. Restrictive legislation has been so successfully implemented in North America that very few birds indeed are imported into this country from there, although no legislation can prevent migration and a few North American breeding species are exported from their winter quarters in Central and South America (see pages 190-192). This is something for which the assessors of British records may be very thankful, since North American birds have always been regar­ ded as among the greatest escape/vagrant problems. However, one cannot be dogmatic even about North American birds, because smuggling is not unknown and licences are occasionally issued for the export of certain species: for example, one British aviculturist is known to have a licence, granted in the United States, to export Sandhill Cranes canadensis for his own use in Britain. Although the total is not large, a surprising number of European birds are imported into Britain and this trade appears to be increas­ ing, if only in a small way. Again, with a few exceptions to be mentioned later, it is not illegal in British law although it all too often contravenes the ill-implemented laws of the countries of origin. Unfortunately from a British record point of view, these are mainly rare or unusual species: for example, Rollers Coracias garrulus are popular, as are—surprisingly—small warblers such as the Subalpine Warbler Sylvia cantillans. A large proportion of the birds arriving and unloaded at Heath­ row Airport—and to some extent at other British airports—are in transit, a great many being en route for Germany and a surprising number for Italy. Those whose journey ends in Britain are intended for zoological gardens, 'wildlife parks', private aviculturists and, especially, the pet trade. There are about 4,000 pet shops in Britain. Not all of these sell many birds (a few, none at all), although some sell nothing else. As distinct from the shops, there are a large number of dealers whose premises range from a small spare room or garden shed to stores of considerable size and accommodating many thousands of birds. (In one back street in London is an establishment, known to few save the initiated, which claims with some truth always to have 60,000 birds in stock.) Although irrelevant to this discussion, it is distressing to note that it is not exclusively the dealers with large premises who deal in large birds, since it is not unknown for about The problem of 'escapes' 181 50 cranes to be packed into a room no larger than a bathroom. Lest the impression be given that all dealers in animals and their premises are as deplorable as unfortunately many of them are, it must be added that the Pet Trade Association—with a member­ ship of 800—is striving hard to improve matters and has instituted a form of voluntary examination which covers not only the housing and feeding of animals but the law regarding them. It is understood that they are trying to obtain statutory legislation to control the animal trade.

IMPORTATION AND THE LAW In various places in this paper the legality or otherwise of exports and imports has been mentioned and, at the risk of repetition, it may be useful to summarise the present position. It does not seem appropriate here to discuss the taking or keeping of British birds in Britain, the law regarding which should in any case be well known. Briefly, there is at present no ban on importing into England, Wales or Scotland any species of live bird except , geese, birds of prey (including ), , quail, , , and all domestic and turkeys. A licence is required, specifying the species and number, for all birds of prey and owls for conserva­ tion reasons, and for all the others for health reasons. Quail Coturnix cotumix are an anomaly in that they come under both headings and two licences are required for them. A limited number of licences to import birds of prey are issued to falconers, zoos and private aviculturists, and in general licences are issued more freely for the other birds. A ban on the importation of except under licence, hitherto in force, was unfortunately withdrawn several years ago. Northern Ireland is rather more enlightened and, in addition to conservation restrictions in respect of live birds of prey (including owls) identical to those applicable in Great Britain, licences are required for health reasons to import almost all species of live birds from ostriches to . Britain has therefore a virtually open door, but this of course does not mean that the birds which enter so freely have left their country of origin equally within the law. North America and Kenya have already been mentioned as applying restrictions on export; a number of other countries attempt to control export of dieir wildlife in varying degrees ranging from a total ban to expres­ sions of pious hope which are in practice meaningless. The greater part of the large British trade in birds is therefore at present within the law. However, on 2nd March 1973 the 'Con­ vention on International Trade in Endangered Species of Wild Fauna and Flora', drafted by the International Union for the 182 The problem of 'escapes' Conservation of Nature, was signed by representatives of 23 of the 88 countries attending. Others agreed in principle but did not immediately sign. Unfortunately it does not come into effect until at least ten nations have ratified it; however, the fact that a number of countries have already signed it shows at least their eventual intention of ratifying it, and it is greatly to be hoped that Britain will be among the early nations to do so. When it becomes effective, this Convention will control the trade in three categories of endangered species of animals and plants. A virtually total ban will be imposed on the export and import of some 400 species in the first category, except in very special circum­ stances. Restrictions on trade in species in the second category will be somewhat less strict, but they will require an export permit from their country of origin. The third category is to enable any country to impose restrictions on the export of its own fauna and flora if those particular species do not come within the first or second lists. Few will doubt that the signing and ratification of this Conven­ tion by a worthwhile number of countries and its eventual effective implementation will be a great milestone in the history of conserva­ tion. In the context of this paper, however, it must be pointed out that it is unlikely to have a significant effect on the problem of escapes.

MEANS OF ESCAPE While it is quite impossible even to hazard a guess at the number of birds which escape from captivity in Britain, it is perhaps useful to discuss briefly how and whence they do so. Except for those comparatively few which are privately imported and personally collected at airports, most of the immigrants pass through a number of hands between the plane which had brought them to this country and the eventual owner. However carefully they are packed—and this is by no means always the case, many packing-cases or cages being very frail—hazards attend almost every move: removal from aircraft to vehicle, from vehicle to arrival shed, examination, removal to appropriate depot for collection or re-embarkation, even well-meant attempts to give food or water, all may give chances of escape. They may need re-packing at the air­ port, they will be transported by road either direct to a wholesaler or to a railway station en route for one. On arrival they will be unpacked and caged, only to be re-packed again and sent, again by road or , to a dealer or pet shop. Thence they will go, usually in a small cardboard box, to their eventual owner. The tricky lids of these boxes present difficulty even to experienced aviculturists, especially when there is more than one bird in the box, although The problem of 'escapes' 183 they usually remember to close the windows of the room when transferring a bird from box to cage, which the inexperienced very frequently do not. Wire-netting corrodes, leaving holes; aviary doors may be left open; birds will whisde past one's elbow during feeding or cleaning. A very frequent source of strangers flying free is the keeper of birds in unroofed pens who, although he knows that they should all be permanently pinioned, has merely clipped their wings before the moult and has put off re-clipping some of them after the moult until it is too late. Undoubtedly not a few birds are deliberately set free because their owners have lost interest in them or are unable to look after them, or because they hope they will remain in the garden if they are fed. Apart from wildfowl, these are almost always com­ mon foreign birds such as waxbills, munias or weavers which are unlikely to be of significance in die present context, however unde­ sirable the practice may be in the light of possible colonisation. Some are given partial liberty in order to find suitable food for young being reared in an aviary (Anon 1969). There have been a few examples of the release of British species in fresh or deserted localities (e.g. Nuthatch Sitta europaea in London) and of winter visitors retained in captivity until after the time of migration in the hope that they will breed in this country when released (e.g. Red­ wing Turdus iliacus, Fieldfare T. pilaris). While it is apparent that there may be many occasions during the captive life of a bird when escape is possible, the risk of escape must not be exaggerated. It should be added that it is remarkable how many birds, having escaped from an aviary, spend a great deal of their time trying to get back into it, and in a high proportion of cases it is only when they have moved so far away diat diey have lost the ability to orientate themselves that they really begin to wander. Although a still-captive mate or companion obviously provides an inducement to try to rejoin it, in many cases the familiar environment of the aviary and its association witii food will prevent wandering, and perhaps even more so will the desire to return to an accustomed roost. However, many—probably most—escapes occur from places where the surroundings are unfamiliar, and in such cases wandering is inevitable. Sometimes these birds find a congenial (if unnatural) habitat such as a garden where food is regularly provided for wild birds, and it is common­ place for them to be reported as being regular visitors over long periods. Generally, escaped and wandering birds tend to search for the type of habitat from which they came when wild, although this is more apparent in the case of large birds (pelicans to estuaries, and cranes to fields or marshes, and so on); during their wanderings, however, they may turn up in the most unlikely places. 184 The problem of 'escapes'

LOCALITY Except in the few large areas of Britain uninhabited by man (or nearly so), birds are kept everywhere and escapes may be seen anywhere. More often than not it is impossible to trace the origin of a suspected escape, although there are the exceptional and obvious cases where, for example, a is seen within a few kilometres of a zoo which has lost one. Despite this, the locality in which a bird is seen is of relevance when considering a record. At first sight it may seem that a bird is likely to be wild if it be recorded, for example, on Fair Isle or in the Isles of Scilly. It is, however, interesting that a number of known escapes have turned up in just such extremities of Britain. (This may be partly due to intensive coverage: few birds which land, for example, on Fair Isle during the hours of daylight are likely to go unrecorded.) Goodwin (1956) told of a Barbary Dove Streptopelia roseogrisea which, having disappeared from his garden in Surrey, turned up in Co. Wexford at the Tuskar Rock lighthouse a fortnight later. Escapes may reasonably be expected to appear at such places while attempting to migrate or while wandering. However, it would be unreasonable not to regard as at least circumstantially good evidence for wild origin the fact that Land's End or the Welsh coast was the place where a certain small North American bird was seen, or Fair Isle a Siberian one. Their alleged occurrence in south-east England undoubtedly added considerably to the plausibility of the 'Hastings Rarities'; would they have been so readily accepted had it been claimed that they were all 'obtained' near Manchester? Similarly, an eastern European or Asian vagrant, if it came to Britain, might be expected to arrive somewhere in the eastern half of the country, although that is not to say that it will necessarily be first reported from there. Place is relevant, perhaps important, but certainly not con­ clusive. The huge consignments of birds passing through London Airport and destined for the Continent have already been mentioned. It is all too easy to think of escapes seen in Britain as originating from captivity in this country, whereas of course continental dealers and bird-keepers are hardly likely to be more careful of their charges, and there is in fact a wider selection of species available from continental dealers. Further, although the Continent has not been spread recendy with such a rash of 'wildlife parks' as has Britain, the large collections in private estates appear to have survived better over there than here. The Continent of Europe must therefore be regarded as a most fruitful source of escapes— especially of larger birds—and the south and south-east coasts of England are their likely areas of arrival. The problem of 'escapes' 185

LITERATURE AND INFORMATION It is remarkably difficult to obtain information about escaped birds and it is too frequently made more so by the apparently inevitable time-lag between the bird's being seen and requests for information reaching the right people. There is no publication which completely bridges this gap, although the weekly magazine Cage and Aviary Birds probably comes nearest to doing so, and its editor has expressed willingness to publish both losses and reports of birds seen which are doubtfully wild. However, on the occasions when this has been done little useful has come of it, presumably because (though most aspects of bird-keeping are occasionally dealt with in its pages) the majority of the magazine's readers are interested primarily in canaries, parrots and the common British , or in bird shows, and unfortunately very few indeed are field ornitholo­ gists. To give credit where it is due, it is obviously current editorial policy to stimulate a greater and wider interest by publishing articles on birds in the wild with increasing frequency. Unfortunately curators of zoos and similar places, with a few notable and welcome exceptions who have given every possible assistance, tend to adopt a couldn't-care-less attitude to the effect of escapes on field records. It is probable also that some escapes go unreported because of the reluctance of an employee to admit care­ lessness. The Zoo Federation News (published by the Federation of Zoological Gardens of Great Britain and Ireland), despite the co­ operation of its editor, is published too infrequently to achieve very much, although such help as it can give is very welcome. The Avicultural Magazine, published every two months, has already printed an appeal for help (England 1970) and is the journal most likely to reach the more serious aviculturists. Indeed, its readers volunteered information about two escaped birds, a Barred Warbler Sylvia nisoria and a Yellow-breasted Bunting Emberiza aureola, neither of which was recorded in the field! Importers and dealers, from whom a large number of birds may be presumed to escape, are—as might perhaps be expected—very mixed in their attitude to the problem. The writer has had courteous but usually negative replies from a few, while requests to others have been completely ignored. Some withhold information for fear that it is being sought in order to bring home an infringement of the law to which, unfortunately, they do not always adhere so carefully as they should; for example, records of Black Kites Milvus migrans have been troublesome for this reason. In any case, even if informa­ tion were forthcoming from some dealers it would be of doubtful value because of their inaccuracy in naming the birds which they offer for sale. On the Continent, Paul Vicomte de la Panouse, Secretary-general 186 The problem of 'escapes' of the Association Nationale de Pares et Jardins Zoologiques Prives, has proved helpful and very willing to assist (though so far negatively); people holding somewhat similar positions in other countries have, on the whole, been as helpful as they were able; while Professor Doctor Heinz-Georg Klos, representing the Berlin zoos, has never failed to respond to appeals for help. Most unfortunately, again with one or two notable exceptions, the least helpful of all are breeders of wildfowl, who are not only responsible for a great many escapes but appear to care little for their effect on records. Further, it is well known that many favour deliberate releases, while not infrequently articles are published advocating the keeping of full-winged 'liberty birds' (see, for example, D'Eath 1973). It must in fairness be added that such escapes are not always deliberate nor due to carelessness. While this paper was in draft several Ring-necked Ducks Aythya collaris were flying around the neighbourhood of my home in Norfolk. These came from a local breeder who is not only aware of, but deplores, the effect of escaped birds on field records. The Ring-necked is not a very free breeder in captivity and those which escaped were some of a brood hatched in a dense reed-bed in one of his pens and which avoided all attempts to catch and pinion them. Much the same happened with the American Black Duck Anas rubripes. As their owner said, 'The only way to stop them confusing the records would be to shoot them, and would you really want me to do that?' I am therefore reluctantly of the opinion that, save in very special circumstances, practically all records of wildfowl can only be regarded as suspect, because of the very large numbers being kept and bred in captivity of almost all the species which are likely to be recorded wild; because the majority of these are kept in open pens and by no means all are permanently pinioned; because many are kept free-flying (while still being fed) or are deliberately released into the wild; and because many breeders of such birds are not interested in field records.

STATE OF AND SOFT PARTS It is often said that a particular bird cannot have escaped from captivity because it was in perfect plumage when seen. An extension of this idea is that birds reared in captivity are never the equals in size, plumage or health of wild ones. Taking the second point first, it can safely be asserted that it is a quite unjustified generalisation and is unsafe as a criterion so far as escapes are concerned. In some cases it is unhappily true; some Australian 'grass parakeets', for example, have for so many generations been bred in inadequate conditions or have become so The problem of 'escapes' 187 inbred that many offered for sale in this country are mere shadows of their wild relatives. On the other hand, aviary-bred specimens of some well-known birds look to a field ornithologist almost 'too good to be true'. Perfection of plumage is even more unsafe as evidence of wildness and is an unfortunate indication of ignorance about aviculture. It is, however, quite reasonable to use the opposite argument, namely that the state of the plumage of a given bird was so poor that it may have escaped from captivity, for the following reasons. First, most wild birds (accidents apart) keep their plumage in remarkably good condition except at certain times, for example after the stress of rearing a family or during a heavy moult; indeed they must do so to survive. There are certain exceptions (see also later), perhaps the best example being the Sacred Ibis Threskiornis aethiopicus. In the wild, the black 'plumes' of this bird always tend to look unkempt, even immediately after , and one might well be excused for thinking that it has recently escaped from rather squalid captivity. Second, many escapes take place during or shortly after arrival in this country. While a very few exporters from other countries take a great deal of trouble over the birds in their care, as regards both health and packing for transportation, the majority, unfor­ tunately, care no further than that the birds should arrive alive (and not always that). As a result freshly imported birds may be in a very bedraggled state due to sticky food, dirty and overcrowded boxes, and the 'bird-lime' with which they have been caught and which is usually lost only after a complete moult. All too often their lot in the hands of dealers after arrival is little better, although it may jusdy be said that a few dealers have an enviable reputation for keeping and supplying birds in first-class order. Further—and this is one of the safer criteria—a bird showing wear about the face is more likely to have acquired this through trying to escape from captivity than in the wild. However, an experienced observer will beware of applying this, for example, to bee-eaters at hole-boring time, or to fruit-eaters such as thrushes, since in both cases the plumage of the face may temporarily get into a deplorable state, though not usually so much so that loss of takes place, less still that bare patches will be seen around the base of the bill. For a detailed discussion of worn or broken wing-feathers see Goodwin (1956). It is usually true that a badly worn or bedraggled tail is more likely to be seen on an escaped bird than on a wild one. It is not only frightened and closely confined birds which spoil the ends of their tails in their efforts to escape or from sheer lack of space; tame or fearless birds in large aviaries frequently break up their tails through clinging to wire netting in attempting to reach human 188 The problem of 'escapes' beings whom they know to be potential providers of food. Some birds, such as rollers, are inveterate wire-clingers and may be the despair of those who try to keep them in good plumage. This is not often seen in the wild; broken, loose or missing tail-feathers may frequently be encountered, but not worn tail ends except in some immature birds and birds of prey. Not infrequently a photograph of a wild bird of prey is spoilt because the end of the tail is, to say the least, untidy. Steppe or Tawny Eagles Aquila rapax and Black Kites, among others, seem especially prone to this disfigurement. It is thus safer to use the argument of bad plumage as evidence of escape than that of good plumage as evidence of wildness, with certain exceptions. The state of the bill and claws may be useful points: both may become overgrown in captivity as a result of an absence of those conditions which lead to wear; and it is not uncom­ mon for small birds which have been caged for a long time to have claws so long that they experience difficulty in taking off from a perch. However, excessive growth of the bill, which is relatively easy to see, is less common than overgrown claws, which may be impos­ sible to note except in the hand. In addition, overgrown and abnor­ mal bills occur in the wild (Pomeroy 1962). Although deformed toes are not unknown in wild birds (being common, for example, in feral pigeons Columba livid), birds captured with 'bird-lime' not infrequendy have distorted digits (sometimes grossly so) with lumps or swellings on or between the joints. Somewhat similar lesions may appear as a result of unsuitable food, perches or floor material. These seldom completely recover. Scaly legs may be seen both in wild birds (Blackmore and Keymer 1969) and—probably more commonly—in captive ones, and are usually due to infestation with a mite, although they may appear with old age. Hitherto, a messy ventral area or repeated jerky motions of a bird attempting to defaecate were indications of the likelihood of unsuitable food in captivity but, although such points should not be ignored, contamination of the environment has unfortunately ren­ dered them less useful as evidence than formerly. The colour, as distinct from the quality, of a bird's plumage is sometimes useful evidence but must be treated with caution. It is well known that some birds tend to lose the red in their plumage in captivity; this occurs, for example, in Linnets Acanthis cannabina and Rose-coloured Starlings Sturnus roseus. Although useful, this is not completely reliable; as has been mentioned, many birds escape shortly after being imported when their colours have not had time to deteriorate. On the other hand, my only experience of the Rose- coloured Starling in the field was of a very tatty-looking specimen with a complete absence of 'rose'; however, since it was in a clearing in the Indian forest it was not likely to have escaped. The problem of 'escapes' 189

APPROACH ABILITY Tameness, approachability and fearlessness, although similar, are not necessarily the same and in any case must obviously be con­ sidered in relation to the particular species. For example, while a phalarope would be expected to allow an approach to within ten metres, a Peregrine Falco peregrinus which did this is hardly likely to be a healthy wild one. With certain exceptions, and provided there is no reason to suppose that it has just completed a long flight across the sea, an alert bird which allows an unreasonably close approach may be considered to be suspect. However, hunger, ex­ haustion, sickness and injury must not be forgotten, since they govern approachability to a great extent, and in my view this is at best an uncertain guide, although of course it is useful as an addition to the total of the evidence to be considered.

FAMILIES AND SPECIES IMPORTED It has been said that, given sufficient financial resources, it would be possible to obtain in Britain any species of bird in the world. This is, unfortunately, not far from the truth, although there are some which would prove very difficult indeed, either because—how­ ever good avicultural techniques have become—they are unlikely to survive the journey from their native land (or indeed survive captivity at all), or because they are few in number in the wild and sufficiently localised and well protected to make trapping and export well-nigh impossible. An obvious example of the latter is the Takahe Notomis mantelli of New Zealand. However, it must be noted that rareness, of itself, is no safeguard that a species will not reach Britain in a captive state: for example, a pair of wild-trapped Siberian White Cranes Grus leucogeranus, which are, of course, very much in the 'Red List', were recently imported for a private collection. However, such birds do not concern us here, and it is almost certainly true to say that any species likely to cause escape confusion in Britain is obtainable by a determined importer. Stated baldly like this, it appears to make the problem of escapes insoluble and it must hastily be added that, although all may be possible, fortunately only few are likely. In attempting to compile a list of species which might be, or might be mistaken for, wild vagrants and which are imported into Britain or the adjacent parts of the Continent in numbers sufficient to make them an 'escape risk', it cannot too often be repeated that the position is continually changing and that the availability of species ebbs and flows. The following birds, therefore, are those currently being imported (or known recently to have been) which may cause confusion either in their own specific right or because they may be said to resemble possible immigrants, even though such i go The problem of 'escapes' a mistake appears unlikely in the extreme to an experienced person. Ducks and geese have been omitted for reasons given above, although it may not be out of place to repeat the classic warning about reporting Ruddy Ducks Oxyura jamaicensis, which are now fairly common in Britain in a feral state, as White-headed Ducks 0. leucocephala. Species which are imported so seldom, or in such small numbers, as to make the risk of escape negligible have been omitted, although this must not be taken to mean that such a thing is impossible. To avoid constant repetition of such phrases as 'moderate numbers', 'only occasionally', and so on, the numbers /, 2, 3 and 4 have been used to indicate very roughly the relative numbers being imported from the area named (/ meaning few, 4 very many), although it will be appreciated that numbers alone do not accurately indicate the likelihood of escape. For example, an escape is more likely from among ten pelicans, which are often only wing-clipped and kept in open pens, than from four times that number of rollers, which are always in cages or aviaries. Countries named are prob­ able areas of origin.

Pelicans Pelecanus spp. (America, Africa and Asia 2). Mainly White P. onocrotalus and Dalmatian P. crispus. Purple Heron Ardea purpurea (Asia /). Little Egret Egretta garzetta (Asia 2, Africa 1). Great White Egret Egretta alba (Asia 2, Africa /). Squacco Heron Ardeola ralloides (Africa 1). Indian Pond Heron Ardeola gravii (Asia 1). More commonly imported than Squacco, especially out of breeding season. Great care needed to distinguish the two species. Bubulcus ibis (Africa and Asia 2). Night Heron Nycticorax nycticorax (mainly Asia 2). It should be noted that there is a free-flying colony at Edinburgh Zoo. White Ciconia ciconia (Africa, Asia and Europe 2). Black Stork Ciconia nigra (Africa and Asia 1). Spoonbill Platalea leucorodia (Asia 2). African Spoonbill Platalea alba (Africa 1). Has red face. Glossy Ibis Plegadis falcinellus (Africa and Asia 2). Phoenicopterus spp. (America, Africa and Asia 3). All species have been imported, the Greater P. ruber quite commonly. Birds of prey. See page 193. Crane Grus grus (Asia /). Surprisingly few imported. Grus antigone (Asia 2). Common in captivity. Anthropoides virgo (Asia 2). Purple Gallinule Porphyria porphyria (Asia 2, Africa /). The Indian race poliocephalus is the one most commonly imported, but this has a greyish head and is easily distinguishable from the nominate form. Allen's Gallinule Porphyrula alleni (Africa /). (Various rails and gallinules are frequently available from Central and South America and from Asia, most of which are hardly likely to be confused with species which might occur as genuine vagrants. However, consignments occa­ sionally include such species as Sora Rail Porzana Carolina, even if only in small numbers.) The problem of 'escapes' 191 Great Otis tarda. Private importations only; a few pinioned birds on Salisbury Plain, Wiltshire. Kori Bustard Ardeotis kori. A few in captivity (and not expensive in African dealers' lists), which should be remembered when a possible Great Bustard is seen. Spur-winged Plover Vanellus spinosus (Asia 2, Africa i). Breeds freely in captivity, and in Lancashire has been reared by incubator in surprising numbers. Three-banded Plover Charadrius tricollaris (Africa 1). Might be confused with Killdeer C. vociferus but is much smaller (size of Ringed Plover C. hiaticula) and has red eye-ring and very conspicuous red base to bill. Black-winged Stilt Himantopus himantopus (Asia 2, Africa /). Pratincoles Glareola spp. More imported than might be expected, chiefly from Asia, though perhaps a few from Africa. Rarely correctly named by dealers, sometimes called 'Eastern Pratincoles'. Probably chiefly Collared G. pratincole or Eastern Collared G. maldivarum, but Black-winged G. nordmanni not impossible. Rufous Turtle Dove Streptopelia orientalis (Asia /). Intermittent, often wrongly named in dealers' lists. Namaqua Dove Oena capensis (Africa /). ( Melopsittacus undulatus and Ring-necked Parakeet Psittacula krameri. Colonies of both species breeding at liberty at several places in Britain.) Owls. See page 193. Bee-eaters. Various species imported from Africa and , chiefly those unlikely to occur wild, although there are quite a number of European Bee-eaters Merops apiaster in captivity in Britain. The colour of the last-named tends to fade considerably. Roller Coracias garrulus (Spain 1). Indian Roller Coracias benghalensis (Asia 2). Easily confused with Roller, but adults have reddish, not blue, face and breast; juveniles more difficult. White-bellied Black Woodpecker Dryocopus javensis (Asia /). White belly distin­ guishes this species from the Black Woodpecker D. martius. Azure-winged Magpie Cyanopica cyanus (Iberia /). Being bred in captivity. Crested Tit Parus cristatus. Seldom imported, but see next species. Yellow-cheeked Tit Parus xanthogenys (Asia 3). Might be mistaken for Crested Tit, but has yellow cheeks and variable black band down belly. American Robin Turdus migratorius. Very seldom imported. Whistling Thrush Myophonus caeruleus (sometimes called Blue or Violet WhisUurg Thrush or even simply Blue Thrush) (Asia 1). Might be mistaken for Blue Rock Thrush (see below), but is larger, slimmer, and usually appears very dark except in brilliant light; very shy. Attempted to breed in Upper Weardale, Co. Durham, in 1970—probably deliberately released (Dr H. M. S. Blair in lift.). Rock Thrush Monticola saxatilis (Spain, Italy and Africa 1). Blue-headed Rock Thrush Monticola cinclorhynchus (Asia 2). Has black eyestripe, rufous rump, white patch on dark wings. Chestnut-bellied Rock Thrush Monticola rufiventris (Asia 2). Larger than preceding species, with no rufous on rump and no white in wings. (African rock thrushes are seldom imported.) Blue Rock Thrush Monticola solitarius (Asia x). Mostly M. s. pandoo, which is slightly smaller and darker (less blue) and generally a duller-looking bird than the nominate European race. See also Whistling Thrush above. Red-flanked Bluetail Tarsiger cyanurus (Asia /—very few). See also Rainbow Bunting on page ig2. Spotted Morning Warbler Cichladusa guttata (Africa 1). Has bred in England several times. Actually a thrush, and might be confused with some other thrushes, possibly Hermit Thrush Hylocichla guttata, but has more upright, flycatcher-like stance. Red-spotted Bluethroat svecica svecica (also L. s. pallidogularis and L. s. 192 The problem of 'escapes' 'robusta' (Asia 2). Throat pattern of males very variable. Luscinia . See next species. Himalayan Rubythroat Luscinia pectoralis (Asia 2). More commonly imported than Siberian. Has black surrounding the 'ruby' throat. Brown Flycatcher Muscicapa latirostris and Red-breasted Flycatcher Ficedula parva. Formerly fairly frequent from Asia, less now, but a few included among batches of small flycatchers (mainly blue with red and brown—e.g. Tickell's Blue Fly­ catcher Niltava tickeUiae) which are still commonly imported. The females of some of these are very confusing. Wagtails Motacilla spp. (Asia 2-3). Some confusing black- and grey-headed examples. See also next species. Citrine Wagtail Motacilla citreola (Asia 1). Shrikes Lanius spp. (Asia 1). Chiefly Great Grey L. excubitor, Bay-backed L. vittatus and Rufous-backed or Black-headed L. schach: last two should be considered if unfamiliar shrike is seen. Rose-coloured Starling Sturmis roseus (Asia 2) Does not deserve its reputation as 'inevitably an escape', though possible. Dullness or absence of pink not a sure criterion for captive origin. Not a ready breeder in captivity, so immatures less suspect. Bobolink Dolichonyx oryzivorus (America /). Yellow-headed Blackbird Xanthocephalus xanthocephalus (America 2). Yellow-headed Marsh Blackbird (also known as Yellow-hooded (Marsh) Blackbird) Agelaius icterocephalus (America 2). Not to be confused with Xanthocephalus xanthocephalus, which is more likely to occur as a vagrant. Red-winged Blackbird Agelaius phoeniceus (America 1). Baltimore Oriole Icterus galbula (America /). Intermittent. Evening Grosbeak Hesperiphona vespertina (America 2). Serin Serinus serinus. Very seldom imported, but see next species. Green Singing Serinus mozambicus (Africa 4). Male differs from Serin in well-marked facial pattern; female more easily confused. Tail not forked. Scarlet Rosefinch Carpodacus erythrinus (Asia 3). Scarlet Tanager Piranga olivacea (America 2). Summer Tanager Piranga rubra (America /). Red-headed Bunting Emberiza bruniceps (Asia 4). Black-headed Bunting Emberiza melanocephala (Asia 2). Yellow-breasted Bunting Emberiza aureola (Asia 1-2). Rock Bunting (African) Emberiza tahapisi (Africa 2). Dark throat and less barring in wings than in Rock Bunting E. cia. Cardinal Richmondena cardinalis (America 2). Rose-breasted Grosbeak Pheucticus ludovicianus (America 2). Blue Grosbeak Guiraca caerulea (America 2). Indigo Bunting Passerina cyanea (America 2). Lazuli Bunting Passerina amoena (America 2). Painted Bunting Passerina ciris (America 1). Rainbow Bunting Passerina lechlancheri (America 2). Has orange breast on arrival, but this soon fades in captivity (unless bird fed on insects, which is very seldom the case), and confusion then possible with Red-flanked Bluetail on plumage characters. Yellow-throated Sparrow Petronia xanthocollis (Asia 2). Slimmer and neater than Rock Sparrow P. petronia, but has yellow throat and rather similar body markings. Bill much finer: looks 'insectivorous' in field.

Domestic Canaries S. canaria are now produced in so many colours and sizes that they should be remembered when an unrecognisable The problem of 'escapes* 193 finch- or bunting-like bird is reported. Colour-feeding is common and colours may range from red and chestnut to green and yellow, with or without dark markings. Streaking is common and the rump is often yellow. Various finch hybrids and canary-finch 'mules' are surprisingly popular and very numerous, but in most a trace of Goldfinch Carduelis carduelis, Bullfinch Pyrrhula pyrrhula or Linnet will be apparent (the red'blaze' of the Goldfinch is seldom completely lost) and snatches of song may reveal the parentage. However, any of these birds may be puzzling in the field, and those considered useless for show purposes are not infrequently liberated.

BIRDS OF PREY AND OWLS Since 1970 it has been illegal to import into Britain, without a licence from the Home Office specifying the species and number, all birds of prey and owls. Despite these restrictions a considerable number are still appearing on the market. However, the Continent is probably one of the main sources of escapes of such species. The commonest eagle is almost certainly the Tawny, although some Spotted Aquila clanga or Lesser Spotted A. pomarina (not necessarily distinguished1) appear from time to time. Various vultures are in surprising demand, as are Black Kites, the latter mainly from Asia though a few are of the African yellow-billed forms. The two most difficult owls are the Scops Otus scops and Eagle Owls Bubo bubo. Before the restrictions were imposed, very large numbers of scops owls of various species and subspecies were impor­ ted (one dealer in the Midlands was receiving 100 a week) and the Continent still receives a number. The main forms involved were Otus scops (Asia /), the White-faced Scops O. leucotis (Africa /), the Bare-toed (or Bare-legged) Scops O. bakkamoena glabripes (South China and Taiwan /), and, commonest of all, other races of 0. bakkamoena, known as Collared Scops Owls, which are very variable in colour and might even be mistaken for the Screech 0. asio of North America. The eagle owls are also very difficult. Many are (or were) imported and a number are bred in captivity each year. Several species are involved, not all so easily identifiable as might be thought. In addition, the Brown Fish-Owl Ketupa zeylonensis came in from southern Asia in some numbers and was often euphemistically named 'Great Horned Owl' by dealers.

OTHER GROUPS AND GENERAL COMMENTS It will be noticed that no divers, or appear in this list (although a very small number of gulls are imported and a fair number—chiefly common species—are kept in some of the larger collections). Nightjars, swifts and hirundines are also absent, chiefly because they do not appear very suitable for aviary life, 194 The problem of 'escapes' although swallows and martins which fall from the nest and are hand-reared do surprisingly well and may live to a considerable age. and pipits are not very popular and, most fortunately, neither waders nor warblers come from America in sufficient numbers to raise serious doubts, except in a very few species. Dealers' lists offering birds for sale may be misleading in two ways. First, because a certain species is listed and priced it does not necessarily follow that it is actually in stock; it may merely indicate that it is obtainable on demand, either from its country of origin or from that avian clearing-house Bangkok or, more likely, from a wholesaler on the Continent. A very undesirable corollary to this is the advertiser who offers to obtain to order especially difficult or rare species. Second, many birds are listed under euphemistic names (see, for example, Great Horned Owl above), some in order to make them sound more attractive, others because the dealer has no idea what they are and has to invent likely-sound­ ing names. (The fact that a particular species is ordered is no guarantee that the birds which arrive bear any resemblance to what has been asked for.) Not infrequently males and females of the same species are listed as two different species; and where the male of a species is colourful and the female drab, importations often consist of practically nothing but males (as in the Red-headed Bunting). It is my opinion that, while in the last resort each suspected case must be considered on it merits, the risk of vagrants being in fact escaped birds is not so great as is sometimes imagined, except in a few cases such as pelicans, herons, egrets, storks, flamingos, waterfowl and birds of prey. The 'problem of escapes' thus arises from the fact that the very wide range of imported species necessarily means that almost every recorded rarity is, to however infinitesimal a degree, tainted with suspicion, and I do not pretend that I have been able to remove this suspicion. However, some comfort may be taken from the fact that, with the exceptions named above, I find it necessary to question from an escape point of view only a very small proportion of the records submitted to the Rarities Committee.

A NOTE ON AVICULTURE It will not have needed much imagination for the reader to have become aware of the fact that I am very much opposed to the almost worldwide and to a large extent unrestricted traffic in wild birds. I might add that I am equally opposed to the keeping of birds in small cages for any length of time. The advertisement pages of such a journal as Cage and Aviary Birds cannot fail to appal anyone with the slightest interest in conservation, nor indeed any thoughtful person with a conscience at all. However, I am an aviculturist and I should indeed be doing a The problem of 'escapes' !95 disservice to my fellow aviculturists and to the minority of conscient­ ious dealers were I to write no more than the paragraph above. It would be difficult to find better words than those used by Seth- Smith (1964) as a dictionary definition of aviculture. What he wrote cannot be quoted in full here, but his opening sentences give an indication of his theme: 'AVICULTURE : term applied to the practice of keeping birds of wild species in aviaries or enclosures, with the object of studying their habits and, if possible, inducing them to breed successfully under conditions as nearly as practicable approa­ ching those found in nature . . . '. It must be admitted that in elabo­ rating his excellent definition he tended to consider the subject (perhaps properly in the context) only from the point of view of its advantages and wrote nothing of the fact that a considerable number of ornithologists and probably more of 'bird-lovers' are opposed to the keeping of birds in captivity in any circumstances. This is not the place to embark on a discussion on the ethics of bird-keeping, but it seems appropriate at least to make some attempt to present briefly a balanced picture. It is difficult to understand how anyone can fail to be appalled at the widespread depletion of wild stock that is going on, or at the conditions in which birds are trapped and transported. Harrowing details would be out of place here: suffice it to say that huge numbers of birds arrive in Europe dead or dying and that a great many more which are just alive on arrival have suffered so much that they will shortly die even in the hands of the most expert aviculturist, hands into which they stand very little chance of falling. Fortunately the picture is not all black. Some of the better public zoological collections and a very few private aviculturists import their birds personally direct from a reputable trapper or dealer in the country of origin. The birds are ordered—under licence where necessary—by species and often in pairs only, from people who are prepared to take trouble to ensure that trapped birds are feeding properly, are in good health, are properly packed for travelling (with instructions for feeding) and are despatched by a suitable route in the care of an airline with a reputation for reliability in the handling of livestock. In such cases it is the rule rather than the exception for the birds to arrive in immaculate condition. Also on the credit side it is not necessary to look further than Britain—although valuable work is being done on the Continent, in the United States and elsewhere—to find examples of aviculture so obviously advantageous as to make sweeping condemnation ridiculous. The work of Professor W. H. Thorpe and others at Cambridge on song (e.g. Thorpe 1961) and of the Wildfowl Trust in saving the apparently doomed Hawaiian Goose Branta sandvicensis show that it is not going too far to say that, for the full under- i g6 The problem of 'escapes' standing of birds and for the ultimate benefit of the avifauna of the world, a certain amount of aviculture in the true sense of the word is essential. Following from this it would be all too easy to adopt a holier- than-thou attitude and suggest that bird-keeping is permissible only if it serves an immediate and obvious scientific purpose. But who is to say that it is wrong for a few pairs of common birds to be kept in an aviary for the sheer pleasure which they give ? Somehow the decimation must be controlled: rarities must be protected; the implementation of international legislation is desperately needed to prevent the recurrence of such events as the arrival in England of the cranes mentioned above. But there are far worse things which the owner of the few common birds might be doing and, since he must already be a lover of birds, it may be only a short step for him to join the ranks of the conservationists.

ACKNOWLEDGEMENTS M. H. Whittaker, in charge of the RSPCA Hostel for Animals at Heathrow, has been most helpful in providing information, and T. P. Inskipp, at present under­ taking a survey of the question of imported and captive birds on behalf of the Royal Society for the Protection of Birds, has allowed full use of his notes and the informa­ tion which he has so far gathered, and has proved helpful in discussion. B. Riley has willingly answered many questions about the sources of imported birds. I gladly express my thanks to a gentleman in the Department of Customs and Excise, who prefers to remain anonymous, for advising on and checking the section on the law. To James Ferguson-Lees must go a great deal of the credit for the fact that this paper was ever completed, since only his continual persuasion overcame the reluctance to rewrite, time after time, matter which became out of date before it could be published. I am grateful to Peter Olney for taking considerable trouble in helping me to avoid mistakes and irrelevancies. Most of all, thanks are due to Stanley Cramp for reading through more than one draft and making many invaluable suggestions for improvement.

SUMMARY The problem of escapes and its magnitude are discussed and some indication of numbers and sources given. Methods of escape are outlined and various aids to differentiation between wild and escaped birds are suggested. A imported which may occur as wild vagrants, and others which may be confused with these, is included. There is a brief comment on aviculture.

REFERENCES ANON, 1969. 'Editorial. Aviculture and the introduction of non-native species'. Avic. Mag., 75: 70-71. BLACKMORE, D. K., and REYMER, I. F. 1969. 'Cutaneous diseases of wild birds in Britain'. Brit. Birds, 62: 316-331. BLACKWELL, K. 1972. 'Escapes'. Northamptonshire and Soke of Peterborough Bird Report 1971: 3. BOYLE, C. L. 1970. 'Control of the importation of wildlife'. Report to ICBP Conference. D'EATH, J. O. 1973. 'On keeping free-winged waterfowl'. Avic. Mag., 79: 70-73. ENGLAND, M. D. 1970. ' "Escapes" '. Avic. Mag., 76: 150-152. The problem of 'escapes' 197 GOODWIN, D. 1956. 'The problem of birds escaping from captivity'. Brit. Birds, 49= 339-349- MARTIN, R. M. 1973. 'The plight of Thailand's birdlife'. Avic. Mag., 79: 131-136. POMEROY, D. E. 1962. 'Birds with abnormal bills'. Brit. Birds, 55: 49-72. RICHARDSON, R. A. i960. 'The trade in birds and its effect on British '. (Unpublished.) SETH-SMITH, D. 1964. 'Aviculture' in A New Dictionary of Birds, edited by A. Landsborough Thomson. London, pp 75-76. THORPE, W. H. 1961. Bird-Song. Cambridge.

M. D. England, Mashobra, Neatishead, Norwich NOR 37Z