XIII. Bush Wren.

The narrow tracks of the island have been described. Originally hewn out by “birders” for their own purpose and from time to time opened afresh, these paths were a boon to us both for convenience of travel and as woodland rides, across which no creature could pass without observation. It was in the light admitted by one of them that a tiny unknown bird fluttered its feeble way late in the afternoon of our first day. About the size of the Wren of the Old Country, and as inconspicuous in appearance, the small stranger proved on further acquaintance to be the Bush Wren of New Zealand.

It had been my good fortune heretofore to note so much of humour, kindliness, good nature, and good conduct in our bird world that observation at close quarters of a new species never fails to raise pleasing anticipations. Then and there, therefore—in natural history there is no time page 142 like the present,—I waited to see more of the stranger whose proximity could be detected by stir of the vegetation into which it had pitched, shivering of fronds, rustle of rough sedge. After many momentary, tantalising glimpses of the bird, which was feeding in company of a mate—I could hear them talking,—one of the pair crossed the path, affording a good view, and corroborating what I had suspected as to species. A few minutes later the second bird, evidently the male, followed, and at once became engaged in warfare with another male, these Lilliputians fighting only a few yards from the tree trunk against which I stood. There was something in the air of the victor and in the determination with which he hustled the trespasser off his domain which showed how keen was his desire for seclusion.

In the bird world, too, there are vested interests, and the tenacity with which an owner will uphold his rights usually gives him the victory in anything like an even match. I judged there must be some special reason for my small companion's wrath, and I was right, for by the time my mates had boiled the billy I had thrice noticed one of of the pair disappear beneath a particular iron-wood bole. Farther than that I failed to follow the bird. The locality, however, was close to our hut, and during the next two or three days all odd quarter and half hours were devoted to the page break

Bush Wren (F.).

page break page 143 observation of the movements of these particular Wrens. Thus we discovered there was certainly a pair, male and female, equally often to be found near the great log. Later again we were able to ascertain a certain route constantly followed. At last one eventful evening I spotted one of the pair bearing a feather in its beak flutter up into the gloom of a frond-hung trunk. For gladness, like the damsel Rhoda, instead of waiting to locate the exact orifice, I rushed off to announce to the brothers Leask the good news. Such happiness granted to mortal by the kindly gods was not to be recklessly dissipated by immediate enjoyment; it was to be frugally prolonged.

Nests of the Bush Wren are unusually difficult of detection, the openings into them even in good light almost imperceptible. Shaded by overhanging foliage and within a foot or two of the dark peat forest floor, they are wellnigh invisible. During search, moreover, care has to be taken not to trample the entrance to such tiny structures, not to block them with trodden fronds and undergrowth. There was another disability too—no mean one either,—we were like all pioneers in search of the unknown, ignorant of the type of locality likely to be favoured. As the British Wren often conforms its colour scheme to the browns of beechen leaf and brake, it had been conjectured that the New Zealander might like-wise page 144 have blent its nest into the material of the rough rufous aspidium crowns. With unavailing care we looked for a dome built in the open; as a matter of fact, we were searching for what was not to be found.

Of the three nests discovered, not one of them was as we had imagined it might be. The first was built somewhere within the mouldering bulk of the huge fallen ironwood already mentioned. Half-way down its dark side, corded thickly with the brown-green vigorous roots of the spotted polypod, was the entrance to the nest. So small was it, even when compared to the size of the little builders, that they could scarcely enter, always having to haul themselves in by many minute, grasping, scrambling movements. The edges of the circular hole, shaded by great dark overlapping fronds, were firmly bound with fibre collected from the durable cores of fallen tree-ferns, its dull blue-black hue matching exactly the rooty coating of the log. The ingress to our second nest, found by John Leask after a search extending over the best part of several days, was even more difficult to determine. It was actually down a Petrel's burrow, an earthy cavern scraped out like a rabbit hole, a vestibule whose disproportionate size made utilisation seem impossible. Although repeatedly, therefore, the Wren was lost to sight in its proximity, none of us could credit page break

Bush Wren With Feather.

page break page 145 that so small a creature would enter its nesting quarters by so vast a cavity. The Petrel passage was not, however, followed far, the Wren relinquishing it for some infinitesimal tunnel passing upwards into the roots of the fern clump which thereabouts covered many yards of ground.

A third nest was found in the rotting centre of a half-dead green tupari—a small tree which in its fall had been wrenched and twisted, and was seamed with longitudinal cracks.

Nothing at first did more to mislead us than the Wren's toleration of dampness in its nesting site. With most species dryness is a prime consideration: follows, holes, and crannies in the least degree moist or clammy are eschewed. Wetness it is impossible always to avoid, but nearly all species secure as perfect drainage as possible, in rainy districts even seeming to select vegetation that rapidly dries itself. A musty air in the neighbourhood of eggs is in fact peculiarly objectionable. Not one, however, of the three nesting sites described was other than damp; one was actually wet. After every shower, into the nest in the ironwood bole, dry feathers were carried in and wet feathers taken out; after every shower in the nest built amongst the fern roots, wet feathers were replaced by dry. The nest in the tupari trunk was the most sodden of all, pressed, as it were, against green wet wood, page 146 reached by a long moist hollow way, and with stagnant water lying within a few inches of the eggs. Into it also dry feathers were carried, and from it wet feathers removed. In the two nests examined there was, however, no mass of feathers; only a sufficiency of blankets were worn; only a sufficiency of feathers stored to meet weather conditions. The more dry ones brought in, the more wet ones to be removed, the birds may have argued. Maybe, too, hunted by their ferocious foe the Robin, they had not yet learned to accept their fate unrepiningly; maybe, too, they were aware of their unmerited handicap in health.

We can credit them, perhaps in some blind confused fashion, deeming that it was no part and parcel of the original order of things that they should hatch their eggs in a musty atmosphere; that it was no part of the original order of things that their neat nest, created to turn rain in the open, and doubtless to joy the little architects' æsthetic sense, should perforce be built in black damp dark. Type of nest construction, nevertheless, after the ancestral model—its craftmanship passed down from happier days—was followed still. Though now a work of supererogation, senseless, since it could neither be seen by the builders nor withstand on behalf of their eggs and young the vicissitudes of climate—the chill page break

Bush Wren (F.).

page break page 147 of night, the heat of day—the dome form of nest still maintained itself.

As in the case of species not commonly met with, forbearance was used in approach to and observation of the earliest discovered nest. It was a pleasant piece of self-denial not more than to glance at it as we went on our ways. Although rats were not, and the Robin and Morepork little likely to do more than bully and intimidate, we felt the fear that permeates all true love; a first nest is to an enthusiast more precious than to a woman her first-born. No attempt to photograph it was made until others had been discovered; its interior structure was never explored. The second and the third nests were, however, exhumed as carefully as might be, examined, and, I am glad to say, replaced without causing desertion. In each we found the entrance to the dome placed low on the side; in each, the stuff used lightly and loosely put together, the careless construction perhaps making such ventilation as was possible rather more easy, or the birds deeming careful art in pitch blackness a superfluous labour.

Fern débris, fibrous rootlets, feathers absurdly large and coarse, often bigger than the birds themselves, were the material used. These feathers were, curiously enough almost without exception, other than those of the Grey Petrel, the common page 148 Mutton bird of the locality. Was this species not in the neighbourhood in the beginning of things? Was the habit of using only the feathers of another Petrel inexpungeably branded into the brain of the Wren ere the Mutton bird arrived? I know not; but those used belonged almost invariably to Dawson's Petrel.

On account of fear of possible desertion, the duration of incubation was not ascertained with exactitude; we believed, however, that the birds of the first nest were sitting when discovered on the 6th of November. On the last day of the month, when I plucked up courage to introduce a finger, the Wren chicks scooped out were judged to be about six days old. There was no down on them; their eyes were closed. Four days later their eyes were still mere slits. During incubation the parent pair changed positions on the eggs at frequent intervals; not only then, but long after the chicks were hatched, feathers continued to be carried in and out. The chicks—there were two of them—were fed by the parent birds on moths, flies, and daddy-long-legs.

The conversational note of the birds amongst the low vegetation, where their lives are passed, is a faint rasping sound, the noise of a small wrist-watch in process of winding. When alarmed or excited they utter a loud cheep.

The nests excised contained in each case two page break

Eggs Of Bush Wren.

page break page 149 eggs—eggs distinctly large for the size of the bird. Each pair of eggs resembled almost exactly the other pair, in each case also one of the eggs differing considerably from its fellow. In both the ground colour was white, but whilst one was altogether clear of dot or blotch or hair like pencilling, the other was sparsely marked with strokes resembling in a general way squares and cubes.

At the distance of only a few feet, many hours were spent pleasantly, if not profitably, speculating as to the why and wherefore of the lives of these little Wrens and as to the enormous terrestrial changes that has forced innovation upon such tiny creatures. The activities of the breed are altogether restricted to movements two or three feet from the ground. They never stray more than a few yards from the tangle where safety lies. Even when close to his own nest, a proximity that endows even a timid breed with some sort of fortitude, I have watched the male wait and hesitate unable to harden his heart sufficiently to dare to make a forward move. The lives of the little harmless fellows are overshadowed by an enduring dread—the dread of the Robin. Passing from log to log, taking cover beneath each gloomy bole, they listen for the snap of its terrible mandibles; they cower before its swoop. Progression therefore over their short Sabbath day's page 150 journeyings is accomplished mostly by discontinuous flights from tuft to tuft of sedge, from stool to stool of fern.

They are at least as active, however, on their legs as on their wings. The hop of the Bush Wren is a remarkable performance. However alike the bird may be, stuffed and stiff in a museum, to its kinsman the Rock Wren, the difference in their hopping movements in life distinguish them instantly and unforgettably. During the first saltatory movement the Bush Wren carries himself parallel to the earth; at the termination, however, of each leap he telescopes upwards on his toes, momentarily erecting himself in the oddest way to his full height. When the two movements are blended in rapid action, what with his whitish feet, short toes, long thin legs, and tightly folded body plumage, he resembles in no small degree a barefooted bairn running on the sands with tucked-up garments firmly fastened round the waist. He passes through the darkling underscrub like a forest gnome, like a woodland brownie.

In the island Wren we may see perchance a minute example of the pressure of species one upon the other in a congested area. We can picture the Wren as he was and as he is. By a very limited exercise of imagination we may visualise him, not confined as now to a few acres on a tiny island, page break

Bush Wren (F.).

page break page 151 but ranging over the forests of a mainland; not laying a clutch of two eggs, the sign of a failing, or at any rate of a curtailed, food supply; his choice of building sites not relegated to damp chinks and cracks; his domed nest not built in the dark; his flight not limited to a flutter of a few yards; himself during incubation not forbidden the warm precincts of the natural day.