Introduction

The study of the forms of life no longer existing on the earth, from the scanty remains preserved to us, has provoked a very great interest almost from the commencement of historical times. The very small portion of this vast field I am treating of in the following pages has a special attraction, as it deals to a great extent with forms familiar in a living state to our immediate forefathers and even to some of ourselves. Although I have here arranged the species systematically, they fall into two distinct categories, namely those known externally as well as internally, and those of which we know bones and egg-shells only. Under the former category might be included those merely known from descriptions or figures in ancient books, as well as those of which specimens exist. In the present work several plates have been reconstructed from such descriptions in order to give some idea of their probable appearance. There is considerable difference of opinion as to the approximate date of the disappearance of many of the species known from bones dug from deposits which have been variously determined as pleistocene and post-pleistocene. It seems to me that this problem can never be entirely solved, but the significant fact remains, that while many bones of these species in one locality have been collected in the kitchen-middens of the former inhabitants, in other localities the same bones occur in what seem to be much older formations.

In view of this and kindred facts, I have mentioned many species which some ornithologists will probably consider outside the range of the present treatise, viz., birds which have become extinct in the last seven- or eight-hundred years. Taking my first category, viz., those species whose exterior is more or less known, our knowledge is very variable in scope; about some we have a very full and even redundant literature, such as the Great Auk, the Labrador Duck, and Notornis, while of others, such as most of the extinct Parrots from the West Indies, the "Giant" of Mauritius, the "Blue Bird" of Bourbon, and so forth, we have the very scantiest knowledge. Even in the times of Leguat and Labat there must have been many species, now extinct, of which no mention has ever been made, for {viii}these old writers only mentioned such species which impressed themselves on their memories either from their size, peculiar shape, beauty of plumage, or excellence and usefulness for food—in fact the culinary property of the various birds seems to have been their principal interest. One of the most interesting phenomena connected with recently extinct birds is the resemblance of the fauna of the Mascarene Islands and that of the Chatham Islands in the possession of a number of large flightless Rails, though the significance of this fact has been much exaggerated.

On the whole, this book is confined to species actually known to be extinct, but a few are included of which a small number is still known to exist, because firstly there seems no doubt that they will vanish soon, and secondly, as in the case of Notornis, it was necessary to clear up certain misconceptions and contradictory statements. In the case of a few species believed to be quite extinct, it is possible that some individuals may still exist in little known parts of their range, while on the other hand it is more than likely that several of the species referred to in my lecture (Proc. Orn. Congress pp. 191-207, 1907) as threatened with destruction, have already ceased to live. This may also be the case with some birds not alluded to at all.

In several instances I have treated of extinct flightless species under genera including existing species capable of flight. This may appear to be inconsistent, seeing that I maintain Notornis separate from Porphyrio, but, while not considering flightlessness in itself a generic character, the great development of the wing-coverts and the modification of the toes appear of sufficient generic value in this case. I know that several of the most eminent ornithologists of the day, among them Dr. Sharpe, differ from me, and are convinced that the loss of the power of flight is so profound a modification, that it is imperative that we should treat it as sufficient for generic distinction.

While agreeing that many genera are founded on much less striking modifications, I cannot concur in this opinion, for, unless the loss of the power of flight is also accompanied by other changes, in some cases it is difficult to find at first sight even specific differences other than the aborted wings.

The cause of recent extinction among birds is in most cases due directly or indirectly to man, but we also have instances of birds becoming extinct for no apparent reason whatever.

Man has destroyed, and is continually destroying species directly, either for {ix}food or for sport, but also in many other ways he contributes to their destruction. Some species have been exterminated by the introduction of animals of prey, such as rats, cats, mongoose, etc., and we know that also the acclimatisation of other birds, such as the mynah, etc., has proved to be harmful to the native birds. Again we find that the introduction of domestic creatures or others kept as pets has brought diseases which may prove fatal to the indigenous fauna. Another means by which man causes immense destruction, is by destroying the natural habitat of various species. By cutting down or burning the forests, prairies, or scrub, and by bringing the land under cultivation, man indirectly kills off a species through starvation, from extermination of certain insects or plants on which it depends for food. Many species, such as the Moas, were evidently greatly reduced in numbers by cataclysms of Nature, such as volcanic outbreaks, earthquakes, floods, bush fires, etc., and then died out from what appears only explicable by the natural exhaustion of their vitality. The chief cause of the extermination of the Moas was undoubtedly their slaughter by the Maoris for food, but in several inaccessible parts of the interior large numbers of Moa remains have been found which undoubtedly had died for no apparent reason.

This cause also seems to be the only explanation of the dying out of such birds as Aechmorhynchus, Chaetoptila, Camptolaimus and others.

The melancholy fact however remains that man and his satellites, cats, rats, dogs, and pigs are the worst and in fact the only important agents of destruction of the native avifaunas wherever they go.