The Domestic Duck

Introduction

For thousands of years ducks have been a source of interest for human beings, mainly for very practical reasons - food and warmth. Duck down from many species, including the famous Eider, has continued to provide very efficient insulation for clothes and bedding. Duck eggs are a good source of protein and in many cultures duck meat has long been a favourite food. Traditionally these were obtained by rifling nests or capturing the birds themselves. For nomadic peoples, raiding nests and trapping or shooting the ducks would have been common activities in many parts of the world. Only when settled communities evolved, around the development of cereal agriculture, were more permanent means of keeping ducks made possible.

Although most ducks are good fliers, it is very easy to 'clip their wings' and impose simple captivity and, because many species nest on the ground, obtaining hatching eggs would be fairly straightforward. What is amazing is that out of 147 living species of ducks, geese and swans, only four of them have provided the bulk of domestic waterfowl throughout the world. Two of these are geese: the Greylag (Anser anser) and the Swan Goose (Anser cygnoides). Two of them are ducks: the Muscovy (Cairina moschata) and the Northern Mallard (Anas p. platyrhynchos). It is the latter that appears to be the ancestor of all but one of the breeds of domestic duck. The Common Mallard is the same species as the big Rouen and Aylesbury as well as the little Black East Indian and the tiny Call Duck. This is all too evident if a Wild Mallard drake flies into the breeding pens and manages to fertilize whatever domestic ducks are on the premises. These birds are highly sexed and highly successful. This is one of the prime reasons for choosing the Mallard in the first place.

Fig 1 The Muscovy duck (Cairina moschata), a perching duck from South America, now common around the world as a farmyard duck. This is a different species from the Mallard, which produced all of our other domestic ducks.

'Mallards rank among the most successful of all avian species, and throughout their wide distribution (which encompasses most of the Northern Hemisphere) they occupy a tremendous variety of habitats, ' writes Frank S. Todd in his Waterfowl: Ducks, Geese and Swans of the World (1979). He goes as far as to assert that the Mallard may well have been the first domesticated bird, pre-dating even the chicken. There are records of the Romans establishing a duckery in the first century using Teal or Mallard eggs. The Egyptians certainly kept Mallard several centuries before the birth of Christ and the Chinese were probably keeping them much earlier. One tell-tale piece of evidence lies in the curled tail feathers of the Mallard, a feature found in all but one of the domestic breeds. Charles Darwin asserts: 'In the great duck family one species alone - the male of Anas boschas [now Anas p. platyrhynchos] - has its four middle tail feathers curled upwardly'.

Another characteristic shared by domestic and wild surface-feeding ducks is the speculum, a patch of iridescence on the secondary flight feathers. It is common to both male and female ducks and tends to be accompanied by black and white bars on the secondaries and greater coverts. This feature is retained in many of the domestic breeds, although it is obscured in some cases by masking genes and various dilutions.

Ancestors

Whether all of the breeds, other than the Muscovy, are derived from the single species of Northern Mallard is a matter for speculation. Certainly, in the wild there are close relative species that will interbreed with the Mallard, just as the two geese species mentioned above will hybridize to produce viable breeds like the Steinbacher and some of the Russian geese. One of the closest to the Mallard is a subspecies, Anas p. conboschas, known as the Greenland Mallard. It is larger and lighter-coloured than its common relative, partly marine in its habitat and requires two years to reach sexual maturity. It looks very similar to the Trout Indian Runner, apart from the upright stance and the Runner's single year to maturity. Another close full species is the American Black Duck, Anas rubripes, which will certainly hybridize with the Mallard, according to Todd (1979). This is a contender for the ancestor of the Cayuga and the Black East Indian Ducks, both of which were developed within the breeding range of Anas rubripes.

The question remains, however: if so many domestic breeds have emerged from such a small family of wild ducks, most of which are very similar to each other, why are the domestics so different? Why are there massive ones and minute ones, black ones, brown ones, white ones, pied ones and Mallard-looking ones? The answer is likely to be 'natural variation' or mutation. Within any species there is a range of genetic material. It is even possible to get the odd white blackbird, but within the constraints and competition for survival of the natural habitat only the most conservative and viable will survive. It is theoretically possible for wild Mallards to generate large white Aylesbury lookalikes, yet what would their chances of survival be in the wild compared to their lightweight, camouflaged, high-flying siblings? Natural selection favours the most efficient adapters to the specific environment. Take away the constraints of the wild; protect the birds from predators and bad weather; give them buckets full of high-protein food and the Aylesbury will survive as well as its wild brothers or sisters - at least until cooking time.

Fig 2 The common tame duck (the Mallard), ancestor of all our domestic ducks except the Muscovy.

The Mallard has the potential for tremendous variation in size and colour, yet it is humankind that has seen fit to exploit this to develop the multiplicity of domestic ducks. This may even be fairly quick to achieve. The Rev. Dixon described his attempts to breed wild ducks. The eggs were taken from a wild Mallard's nest and hatched under an ordinary duck.

Until a month old, we 'cooped' the old duck, but left the youngsters free. They grew up invariably quite tame, and bred freely the next and following years. There was one drawback however. Although not admitted when grown to the society of tame ducks, they always, in two or three generations, betrayed prominent marks of deterioration; in fact, they became domesticated. The beautiful carriage of the Wild Mallard and his mate, as seen at the outset, changed gradually to the easy, well-to-do, comfortable deportment of a small Rouen, for they, at each generation, became much larger.

Their wings no longer crossed over the rump in a ready flight position, but dropped down at their sides like the larger domestic ducks.

Classic Ducks

During the course of this book we will refer constantly to two kinds of domestic duck: the 'classic' and the 'designer'. We make no apologies for such coinage: the terms refer to very different forms of development, as we will try to explain.

The 'classic' ducks are typically those featured in the earliest books of waterfowl standards and those still tending to win most prizes in major exhibitions. They include the Aylesbury, Cayuga, Pekin and Rouen, in the heavy breeds, as well as the Bali, Black East Indian, Call, Hook Bill, Indian Runner and the Crested Duck, in the lighter varieties. What is special about these birds is the nature of their evolution compared with the more deliberate engineering of the later 'designer' ducks. Classic ducks evolved in different geographical areas over what may have been long periods of time. They were developed in some cases for meat, like the white Aylesbury with its clean-looking carcass, large body and light-coloured meat. They were also developed as economical foragers, like the so-called Indian Runner that gleaned its food from the padi fields of Indonesia and was famed for its prodigious egglaying. They were developed as Decoy Ducks, the alternative name for the Call Ducks, because of their portable size and loud quacking, which brought wild ducks down to the guns of wild-fowlers or into the mouths of great cage traps (koys). Each 'breed' of duck had a very special pool of genetic material. Until the nineteenth century it is very unlikely that the last three mentioned birds were ever 'live' in the same continent together, let alone the same collection. They were unique simply because they were not mixed.

Fig 3 The Muscovy Duck, Anas moschata. (Illustrations from Willughby, 1678; photocopy; by permission of the British Library)

Although based on the same ancestor, the birds evolved in different geographical areas because of the limitations of human travel. As long as it took months to journey to China by horse, camel or sailing ship, there was little chance that voyagers would bother carrying anything so trivial as a duck, apart from the odd dinner. It is only when transport became easier and the Western nations began to open up their empires all over the globe that an interest in exotic waterfowl really 'took off. Until then the British slowly developed their Aylesbury; the French developed a parallel form in the Rouen; the Chinese produced the Pekin; and the archipelagos of South East Asia concentrated on the perambulatory egglayer, the Indian Runner Duck. These bird populations were largely restricted to distinctive gene pools because of the original travel problems.

Fig 4 Pekin drake. The property of Mr F. A. Miles: first prize Crystal Palace 1910, etc. (The Feathered World, 23 June 1911)

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