I have only watched them in the neighbourhood of towns, where they become objects of interest to passers-by, and especially to those great enemies of birds-the small boys,-they are in such localities subjected to an amount of attention and persecution which they do not receive in more sequestered parts. I have attempted to find whether the colour changes recorded are permanent, or merely transient, but have not been able to obtain evidence on the subject. I think it will be found on examination that very frequently abnormal colouring at one period of the bird's life may disappear at succeeding moults. Mr A. Binnie tells me that a dealer got a pure white goldfinch in a catch near Dunedin one day. He refused 10s. for it. At next moult it reverted to the natural colour. He also stated that another bird was nearly black, but it retained its colour at successive moults. Writing now (1917), nearly thirty years later, I consider that the inferences I drew from my own observations were wrong. I was so busy looking for anomalous characters that I met with a good many, and so came to the conclusion that they were on the increase, but I cannot find now any more white, coloured, or white-feathered birds than were to be found in 1876. There are different varieties of birds in different parts, but no variation seems to be now taking place more than occurred before. The race of house-sparrows common in Wellington appears to be of a darker brown colour than those common in Canterbury and Otago, but this would merely show that a darker strain was originally imported into the Wellington district. Similarly my observations on rabbits do not show that there is any tendency to the production and perpetuation of multi-coloured varieties. I thought differently in 1891, when I wrote: In the neighbourhood of towns and villages, where cats and dogs, and sportsmen abound, the sober greys and browns of the wild rabbit are the colours commonly seen; but in the country districts, away from all enemies except professional rabbiters and phosphorised oats, neither of which are likely to exert much selective action on their colour, it is as common to see black, white, yellow, and piebald rabbits as the ordinary greys. It is clear that I did not attach much importance to the native harrier as an agency for keeping down the rabbit pest, nor do I now. The subject could almost be treated numerically, for skins are exported by the million every year, but I have been unable to obtain exact figures. However, rabbit-skin dealers and exporters tell me that black, white, buff, yellow and piebald skins do not tend to increase at all in numbers. One large exporter informed me that greys amount to about 97 per cent. of all the skins which come into the market. Mr B. C. Aston, in an account of a trip to Marlborough makes an interesting remark on the colour changes in introduced animals, to this effect: The strong insolation of the area, is, I think, affecting the colour of the wild animals, goats, pigs and rabbits. Where the normal colour is khaki, as in rabbits, melanism is very frequent, but in the Clarence valley, bicoloration is common. This in a pig makes for better concealment. I noticed this particularly. A huge spotted boar running on a hillside about a mile away was conspicuous owing to his movement, but he disappeared as soon as he stopped. Seasonal changes common to certain species in the Northern Hemisphere tend to be reproduced in New Zealand, wherever the climatal changes correspond. Thus in the colder parts of Canterbury and Otago, where severe winter frosts are often experienced, hares, stoats and weasels tend to grow white winter coats. But I have no record of such changes occurring in the warmer districts. The introduction of stoats and weasels, which was undertaken primarily as an antidote to the rabbit pest, has had other far-reaching consequences on the introduced fauna. It has certainly helped to prevent the establishment of such species of birds as partridges, ducks and other game birds; and it has probably also greatly reduced the reproduction and spread of well-established birds like pheasants. On the other hand it has enormously reduced the numbers of rats and mice in the country, and in this way may have indirectly helped in the preservation of the native weka (Ocydromus), and the Californian quail, both of which appear to have increased of late years, in districts where stoats and weasels are quite common. Probably also the humblebees have benefited by the destruction of mice. It might be thought that the reversal of the breeding season between the northern and southern hemispheres might affect introduced species, but no such changes have been recorded. With introduced individuals it might be noticeable. I am informed by bird fanciers and dealers that some introduced birds suffer very seriously at the moulting season. This is particularly the case with imported canaries; but these are highly artificial and domesticated birds. Scarcely any attention has been paid to the relations between introduced animals and plants and indigenous species. It is, however, probable that native ichneumon flies have found suitable hosts in several species of introduced insects, but no one seems to have kept any definite record of the facts, if they have occurred. One definite example has been frequently reported. A native ladybird-Coccinella tasmanii, White-which is common in both islands, has been found to be very destructive to melons, cucumbers, etc., and also to Schizoneura iangigera, Haus., the woolly aphis. The larva of a native moth-Cacacia excessana, Walker-forms a tough netting and covers it mimetically with dead leaves, under which it lives. Mr W. W. Smith has noted it as common on the surface of the leaves of the laurel (Prunus lauro-cerasus), and on many of the cultivated fruit trees. Other examples of interaction between native insects and introduced plants are given in the next chapter. Chapter XIV ALTERATION IN FLORA SINCE EUROPEAN OCCUPATION OF NEW ZEALAND THE HE changes produced on the indigenous vegetation by the introduction of new types of animal life have long been under observation by many competent naturalists, and are more easily followed than those which have affected the native fauna. The subject has been dealt with by many writers. I have dealt with it in some detail when referring to individual species of animals, so I will only give a general summary here. Cattle, sheep, goats, horses, deer, pigs, rats, and especially rabbits, have done a great deal of damage in many localities by eating down, and in some cases by eating out the native vegetation. Some mammals and several kinds of birds have actually brought about an increase of the indigenous flora by distributing the seeds of a few species of plants. Introduced insects have produced very considerable changes, but they are somewhat difficult to follow, and have only been partially recorded. No instance can be recorded of any species of native plant which has been exterminated owing to this or any other cause dependent on European occupation of the islands. But local extermination has taken place, and the following cases can be cited. Lepidium oleraceum, Forst., was formerly abundant round the coasts of all parts of New Zealand, but is now becoming very scarce. Cheeseman says of it: It was originally discovered by Banks and Solander during Cook's first voyage, and at that time must have been abundant, for Dr Solander speaks of it as "copiose in littoribus marinis," and Cook states that boatloads of it were collected and used as an antiscorbutic by his crew. It is now quite extinct in several of the localities he visited, and is fast becoming rare in others. Its disappearance is due to cattle and sheep, which greedily eat it down in any locality they can reach. Aston remarks that it "has been eaten out along the Wellington coast, and is now generally only to be found growing on inaccessible rock-faces." The same is to be said of it in Otago, where it is now extremely rare, though abundant forty years ago. Speaking of Hibiscus Trionum, Linn., and H. diversifolius, Jacq., Cheeseman says: "Both are being rapidly destroyed by cattle, fires, etc., and are now rare or almost extinct in localities where they were plentiful twenty or thirty years ago." Entelea arborescens, R. Br., is "greedily eaten by cattle and horses, and consequently is fast becoming rare on the mainland, except in comparatively inaccessible situations. It is still plentiful on most of the small outlying islands on the north-east coast of the Auckland district." Pomaderris apetala, Lab. This species was formerly abundant at Kawhia, but is now extinct there, having been completely exterminated apparently by goats-according to Kirk. It is now restricted to the South Head of the Mokau River, and to the Chatham Islands. It is clear, however, that it must formerly have had a wider distribution over New Zealand, for it is a common Australian species, and therefore it would seem probable that its extinction in this country was proceeding apace even before goats were introduced. Clianthus puniceus, Banks and Sol. This plant, according to Cheeseman, is "exceedingly rare and local in the wild state, and is fast becoming extinct. It was formerly cultivated by the Maoris in many localities on the shores of the North Island." I mention this species here, not as an example of a plant undergoing extermination owing to the direct action of man or of the animals introduced by him, but as one which was evidently dying out when Captain Cook first landed in the country. Why it should have been in this decadent state I cannot suggest, but it must have been widely spread in former times, for it and an Australian species C. Dampieri, A. Cunn., are the only two species known. It is now common as a cultivated shrub, but does not seem able to re-establish itself naturally. There is a popular idea that Clianthus puniceus was introduced by the Maoris. This is expressed by Taylor in Te Ika a Maui as follows: A better gift, was, I believe, the Kowai-ngutu-kaka (Clianthus puniceus), which was most probably introduced by his ship. The Taranaki slaves, when released by the Ngapuhi on their embracing Christianity, took the seed with them as a remembrance of the land of their captivity. The botanist would naturally ask, from whence did they bring the plant? There is no trace of a Clianthus in no trace of a Clianthus in any Melanesian or Polynesian island, as far as is known. Angelica Gingidium, Hook. f. This plant was formerly extremely common throughout both islands, but "as it is everywhere greedily eaten by stock, it has become scarce in many districts." Myostidium nobile, Hook., is now found in many gardens in both islands, especially near the sea, where it thrives. But in its native habitat in the Chatham Islands it is now quite rare as a wild plant, though formerly it was very abundant. Cattle and pigs have eaten it out. This is another species which was on the verge of extinction |