The life of a swan

Press, Volume CXII, Issue 32975, 22 July 1972, Page 10

The life of a swan

The Swans. Peter Scott and the Wildfowl Trust. Michael Joseph. 242 pp. Index. (Reviewed by J.W.) This book reviews present knowledge concerning the eight species of large waterfowl we call swans. Following a short general introduction by Peter Scott, there are chapters by different members of the staff of the Wildfowl Trust on classification; distribution, numbers and migration; food and feeding; reproduction; mortality; swans in art and mythology; their exploitation and their conservation. The book is copiously illustrated with a coloured frontispiece and many attractive and relevant sketches by a wide range of artists. The drawings are supplemented by many black and white photographs of swans in various parts of the world from Lake Ellesmere to Montana; from Japan to Iceland. A series of appendices provides tables of vital statistics for swans, their eggs, and their foods. The bibliography of 350 references includes papers published up to and including 1969 and a few as late as 1970, thus providing a good lead-in to the literature of these birds. This book is a mine of information about swans, their modes of life and ecology, how they are being studied, looked after and conserved. Like most species of animals, swans are threatened in various ways by man’s activities, sometimes deliberately, sometimes

accidentally. Some swans breed well in captivity (and information about how to look after them is given) but others do noL Only four of the eight species have done well at the Wildfowl Trust. The Black Swan poses few problems in conservation and seems to be one of the most adaptable of swans and now breeds extensively in several parts of the world away from its native Australia. The long chapter by Janet Kear on reproduction and family life is one of the best and most detailed in the book. From her we learn that most swans do not breed usually before they are three or four years old, that they need territories (defended areas) if they are to breed successfully, that they tend to retain their mates from season to season but that divorces do occasionally occur. Similarities between the displays of Mute and Black Swans indicate that they are closely related despite their external differences. The Black Swan is particularly well Atted to breed in varied environments as it has acquired the ability to remain in breeding condition throughout the year and so can nest at almost any month when conditions are favourable. This is presumably an adaptation to the Australian habitat where water levels and rainfall are often variable and capricious. At Lake Ellesmere the bird is a seasonal nester but in Northland is more variable, so that at some places cygnets may be seen in almost any month of the year. The chapter on exploitation of swans includes the information that in 1966 43,200 Black Swan eggs were collected at Lake Ellesmere, selling at a dollar a dozen. Initially they were used to make a chocolate malt drink but pressure from poultry fanners put a stop to that ana such eggs are apparently used now either in Christmas baking or fed to racehorses! An amusing cartoon by Giles purports to convey the swan’s thoughts on stable hands and racehorses . . . Perhaps it is just as well that there are no descriptions in this book of the battues called “Swan drives” that occur in New Zealand and Tasmania at places like Lake Ellesmere, and Moulting Lagoon. The work appears to have been carefully edited and there are few evident errors. One on page 32 should perhaps be mentioned: the two types of shading in the diagram mean just the opposite of what the caption states. According to the blurb the book is intended for both the layman and the specialist. The latter would, however, have found the data in the tables of more value had they been presented in the standard statistical form, particularly as the sample sizes are often large. All in all, this is a book to be thoroughly recommended for those interested in swans, wildfowl, and in the activities of Peter Scott and his associates.