NEW BOOKS AND NEW EDITIONS

New Zealand Mail, Issue 1831, 10 April 1907, Page 29

NEW BOOKS AND NEW EDITIONS

Our. Feathered Friends: Evidence for and against introduced birds in New Zealand: together with-notes on tho native avifauna.” By J antes Dm ininond.

This useful pamphlet is issued as

“Bulletin No. iU,” by the Division of Biology and Horticulture of the New Zealand Agricultural Department. The letterpress is preceded by a number of illustrations of fi.: ropes u sp-scies that have with greater or less success adapted themselves to a new environment in this colony.

Trie genesis of the pamphlet began with the preparation by Air Drummond of a series of twenty-nine questions regarding introduced birds, the effect of their presence on crops and on the native avifauna, and so on. This list was issued by Mr Kirk, Government Biologist, to resident's in various parts of the'colony, and trie replies received were classified and tabulated by Air Drummond. The resulting table is preceded by a brief general sketch of the conditions obtaining in New Zealand before European birds were acclimatised hero, and the sentiments and circumstances which induced the early settlers to undertake what w-e now regard as for the most part a deplorable series of experiments.

Among the circumstances specially singled, out to account for the presence of tho sparrow and other destructive small birds, Mr Drummond enlarged on the “blasting plagues” of caterpillars that at intervals used to devastate the crops of * the settlers, like occurrence of these plagues is well within the memory of many settlors still living, but or the nun deeds of correspondents who have replied to Mr Drummond’s questions “there arc only six who raise their voice in ’be sparrow’s favour.” These six are in such a minority that one might at first view imagine their evidence wholly overborne by that of the adverse hundreds. But is such a judgment logical? Is not the evidence of one trained and painstaking observer worth that of a hundred who, biassed by loss of a. proportion of their crops, voice their prejudices without duly weighing evidence ? Even though the majority . rchides the name of Mr Kirk, who is supported by the outside_ evidence of several British and American entomologists and ornithologists, there seems yet a word to be said for the sparrow. Among the minority of six we find such close reasoners and trained observers as Mr G. M. Thomson, of Dunedin, and Mr H. 11. Whakespere, caretaker of the Bird Sanctuary at Little Barrier Island. These admit, as indeed everybody must, that the sparrow i 3 a destroyer of grain and garden crops, but claim for him that he counterbalances this by destroying a deal of insect life. (Summing up the evidence for and against the sparrow, Mr Drummond says it “stands condemned on the almost unanimous vote of the farming community of the colony. It i 3 proclaimed a public nuisance, and the mitigations of its offence are evidently so slight that they are deemed hardly worth considering. Whatever the sparrow may do in these times, however, there is no doubt that it did good service to the agriculturist and horticulturist of New Zealand in former days, when the insects were on the war-path, and the people were liable to be eaten out of house and home. A new generation has arisen, and only the sparrow’s faults are remembered.” Some interesting questions that have a distinct bearing on the matter of the caterpillar plagues, with the suppression of which, the sparrow seems fairly to be credited, are these. Wore the caterpillars of those days, or rather their parent moths and butterflies, indigenous species, or were they importations from Europe or elsewhere which increased enormously because »;f the absence of their natural enemies? If they were indigenous species, were they stimulated to vast increase by the presence of the cultivations of the Europeans settlers? Again if they were native species, how and why did they so readily adapt themselves to and prefer new foods such as their arcestry had never had any acquaintance with? These questions are not asked as mere conundrums. Tney have a scientific bearing on the usoiUlness or otherwise of the sparrow and other European: birds. If they were native species, why did thsy so greatly exoaed. feeding capacity off 'the naJlve 2«**da? Iff they vara European species.

it is easier to understand, the usefulness in their destruction of the sparroiv and other imported birds. In Australia, forty or fifty years ago, the same phenomenal outbreaks of insect life were familiar to country settlers. Among the hosts of caterpillars that would now and again sweep over the country there were, judged by their external markings, quite a number of different species ; but neither before nor after the appearance of such plagues was their any abnormal increase in the number of moths or butterflies. Australia had in those days, as it has still in less degree, a host of insect-eating native birds, and while a caterpillar plague lasted, these battened on tho liberal banquet. Crows, magpies, shrikes, native larks, magpie larks, plovers, wren:-:, robins, fly-catchers, hawks, and a host of others all played their beneficent parts, but it cannot be said that their efforts made any appreciable abatement of the passing plague. But there oarno a day when the sparrow, as in Now Zealand, increased and multiplied, and pari passu, the caterpillar plagues grew less and less frequent and less and less overwhelming in numbers. It would be to commit a logical error to say without better evidence “post hoc ergo propter hoc,” but the coincidence is at least suggestive. Is it not probable, as suggested by Mr G. M. Thomson’s remark, “It is a common sight to see sparrows chasing moths and other insects on tho v. iug, and lighting down on the load to strip their wings off,” that the sparrow really acts as a preventive of caterpillar plagues? Personally, while not wholly convinced for or against the usefulness of the Old World bird importations, we incline to the view that the farmers opinion is not the best class of evidence. The fanner sees his losses in grain, fruit, and garden-truck, but he does not see all the sparrow eats, and is too apt to be guided by the obvious injury to his crops. Space docs not permit of notice in detail of the several introduced birds whose merits and demerits as colonists rre examined by Mr Drummond and his correspondents. One only we must not omit. It is a curious fact that in New Zealand there is, in Mr Drummond’s words, “hardly any limit to the good words said of the starling.” After close and careful observation of the habits of that bird, after shooting many dozens to examine the food in their crons, we can heartily add our mite of testimony to the words said in its favour.

The praise, and well-deserved praise, of the New Zealander is curious as contrasted with the equally well-deserved blame of the Australian farmer and orchard rot. “It may be pointed out here,” s„ys Mr Drummond, “that the starling has given rise to something more than suspicion in Australia, where the gravest possible charges are mado against it, and these charges are evidently based upon evidence that cannot be discounted.” Briefly, ibe Australian starling has become a premature thresher of ripening wheat, and a wholesale plunderer of orchards. He is convicted of these crimes on the best evidence, and in many parts or the Commonwealth a liberal price is put on his head. If the starling in New Zealand is almost wholly beneficent, how is it that the same species in Australia has become an outlawed bushranger?

A long correspondence in the Melbourne papers a year or two ago was almost unanimous in its condemnation of the starling, but though all condemned, nobody attempted to explain the peiky little bird’s sad degeneration in' habit and character. And yet tho cause is fairly on the surface. The starling is naturally a bird of lush meadows and moist cultivated fields. In his natural climate and habitat, wirms. crickets, and other succulent animal food are abundant on and near the surface of tho soil. In Australia, with its blazing summers and parched soil, the poor starling is for that season a stranger in a strange land and climate. Worms, his main food, bury themselves feet deep in the soil, and he has to share the other insects with the magpie, the crow, the shrike, and other aggressive birds which cannot be driven away from their feeding grounds by anything so physically contemptible as a starling. He suffers from a pinched belly, and is driven to resort to other and more accessible forms of food. He is an adaptive chap, and does not repine.

Fortunately for him, the summer season is also the season of fruit, fruit moist and luscious, and affording him just the substitute for the fat, juicy worm that his heart longs for. Therefore he takes toll of the cherry and tihe plum, the apricot and the peach, the apple and the grape, each liberally in tts season, and doubtless also offers up his thanks that there is corn in Australia. The farmer and the orchardist likewise take toll of him with murderous firearms a,pd manifold other ingenious devices, but his individual life is nothing, and his kind lives and prospers. For a temporary home for his teeming young, there are hollow trees on all the trees and flats, and if he cannot bully and browbeat the crow and the magpie on their feeding grounds, he ca» ?&> hmA

eject the tree swallow and the parrot and other small fry from their ancestral nesting places, and feel himself happy and at home in the hollow gum tree.

But, as Mr Drummond says, when commenting on his fruit-eating habits, “these facts point to the great need for caution when fresh importations are being considered.” On the whole question of the benefits or otherwise arising from the introduction of European birds, Mi Drummond concludes that the answers received “leave no doubt whatever that a vast majority of the classes of tlie community most interested in the doings of birds firmly believe that their introduction was a disastrous mistake, that they do immeasurably more harm than good, and that their banishment, if it was possible, would be exceedingly desirable.” For hipiself, Air Drummond agrees‘with the minority, who “modify their condemnation by expressing an opinion that if the birds could be kept in check, they would be converted from enemies to friends. I cannot help thinking,” ho adds, “that that is tho pruper altitude to adopt. The birds are far from being altogether bad. A forget, ful generation may have a short, memory, but great services given in the past must not be ignored when the birds are on their trial.”

After giving data for an easy computation of the losses caused by birds! by adopting an estimate of 5s an acre on 706,584 acres, Mr Drummond proceeds to consider the best method' of keeping the small birds in check, and plumps for the “dry method” ol poisoning presently to be enforced by the Agricultural Department. Among other information on a variety of germane topics, Mr Drummond gives, in the order of preference, a list of further bird introductions suggested hv several of his correspondents. These total thirty-five species, beginning with the robin and ending with the butcher-bird, though as the latter bird, under its other name, the shrike, figures fifth on the list, it has probably lost a vote or two by double nomenclature, and added one too many to the list of snecies.

Finally, as a useful and instructive work, on the whole well done, and full of information, the pamphlet may be warmly recommended to all who feel interested in questions of acclimatisation. Mr Drummond, and Mr Kirk, and his staff, who aided Mr Drummond in the obtaining of the necessary information, have conferred a distinct benefit on the landholders of the colony and on all students of bird life under new environment.