NATURE NOTES.

New Zealand Herald, Volume LXIV, Issue 19720, 20 August 1927, Page 1 (Supplement)

NATURE NOTES.

A SWEET MELODIST,

UV J. DRUMMOND, F.L.S., F.Z.S.

A note sent from Waiuku by Mr. A. King on August 3 brings to mind a little New Zealand bird whose modest dress and manners rob it of much of the attention it deserves. " You may be interested to learn," Mr. King wrote, " that the riroriro has been about here for the past five weeks, and in the early morning, regularly, may be heard in particular trees near this township." With a grey-ish-olive mantle on back and shoulders, grey on the throat and breast, and white, tinged with yellow, lower down, the grey warbler is not .noticed as often as it is heard. For weeks its trill, sweet, clear, and distinct, but subdued, plaintive but merry, has been uttered in every part of New Zealand, from hedges, forests trees, and shrubs, in fields, riverbeds, and even city and suburban streets. ' The songster may sit on a fence close to a bedroom window in the residential area of a city, and sing in the early morning, the notes falling on the ears of a person awaking from slumber. They often are the first sounds heard in the day by bushmen and prospectors who live in huts or tents far from civilisation. People who pass along country roads hear the notes again and again, and stop to listen and to catch a glimpse of the songster. No other bird, probably, lias a song like the grey warbler's. Its effort is distinctly avian in character, but utterly unlike the far-famed songs of the songthrush and the blackbird, for instance, or the chimes of the tui and the bellbird. The grey warbler has many themes. The character of the song changes, but always the song is unmistakable, whether the notes are whispered softly or are trilled in a crisp, detached staccato. In spite of the grey warbler's popular name, its song is more a trill than a warble. The tones are smoothly gliding. They are utterly devoid of shrillness. They quaver slightly, but, usually, are not very flexible, although a great deal of variation, by close attention, has been noted in individual songsters; and the song is not a song; it is a soft, sweet flow of melodious sounds, a melody, in fact. There is no comparison between the grey warbler's performance and the performances of the song-thrush and the skylark, to select the greatest songsters -in New Zealand, simply because there is no basis on which to compare them. Sir Walter Buller associated the trill with the hum of bees among flowers and the stridulation of the cicada in the sunshine. Few bird-notes are imitated more easily by whistling. The grey warbler, perhaps, accepts this as the sincerest form j of flattery. It. responds by coming closer. The rapid twirling of a leaf, representing a flutter of a captive bird, will bring a grey warbler to the open hand. A strange feature of the song or melody is, occasionally, a sharp and abrupt termination when it* is half-way through, as if the songster —or melodist —had been singing to itself, and, suddenly becoming aware of the presence of a listener, was overtaken by shyness and did not complete the theme. The plaintiveness of the note suggests a somewhat melancholy disposition. The truth is, the grey warbler is one of the most cheerful and lively pf New Zealand s native birds. It has a friendly outlook on the world, does not shun human-beings and their manifold activities, and seems to be well disposed to all other creatures. This may account for its willingness to take up the burden of foster-parentage to voung cuckoos. More eggs of New Zealand's two cuckoos are found in grey warblers' nests than in the nests of any other species. People who have seen grey warblers feeding young cuckoos aie amazed at the foster-parents solicitude for the greedy voracious and clamorous aliens that usurpingly occupy the little birds' nests. In the grey warblers; bearing there is genuine and deep anxiety to meet all the young cuckoos' exacting demands, an anxiety which, strangelv, has not been noted in the grey warblers attitude to their own young. Grey warblers' nests are sent in by correspondents fairly often. In some, there are white, fragile eggs, usually suffused with a pinkish tinge, sometines spotted with .red, and occasionally pure white. They are dainty jewels, a pleasure to see and to handle" In a few cases the grev warblers' eggs had disappeared from the nests. In their place was the much larger, uniform, brownish-olive egg of a shining cuckoo or a long-tailed cuckoo. The nest almost always is pensile. Its roof, a tapering point, is hung by strong fibres to a branch or a twig, if the nest proves to be somewhat unsteady, stays or guys are placed from it to other supports on the tree or shrub. Two builders watched by Mr. Johannes Andersen, began at the top and worked downward. As the pear-shaped dwelling progressed and began to swell out, work was done underneath as well as at the sides. The builders seemed to work upside down as easily as in any other attitude. When only the lining had to be done, both of them approached the male with a feather. The female foUowed him with ruffled feathers and shivering wings. They approached leisurely, settling, twittering, hopping a short distance, flying a few inches, evidently in exuberance. The whole exterior may be covered from top to bottom with the green nests of a particular and very common spider, Epeira verrucosa. A nest has been found gaily decorated with long dry leaves of the red gum, which hung to the sides like streamers. Moss, wool and down, bound compactly by cobwebs, are used, and feathers, string and cotton may be woven in. Soft feathers seem to be the favoured material for the thick lining. The small entrance is at the side, and often this is surmounted by a narrow porch, which helps to keep out the rain. Two broods are reared each season. Five eggs were taken from a nest -on November 29 one year. On December 1, the owners began to build again. In sunshine, rain and snow, the work went on. The nest was completed on December 5; the first egg was laid on December 8, the* second on December 11, the third on December 12, the fourth on December 13; and the female then began to sit. In this case, the male did most of the work in collecting the material for the nest, but, by the division of labour, the female did most of the work in weaving the materials together and in building the nest. Ihe bottom of the chamber is about two inches below the entrance. A grey warbler's nest is one of the warmest, the most comfortable, and the cosiest cradles in the world. The cuckoos are extraordinanly callous in shunting their young on to other birds, but there is evidence of good judgment 111 their selecting grey warblers', nests as homes for young cuckoos, and in appointing grey warblers the foster-parents.