Kiwis, Or Wingless Birds Of New Zealand

( Originally Published Early 1900's )

OF the many strange birds found in various parts of the world, perhaps none is more curious and generally interesting than the Kiwis, or so-called Wingless Birds of New Zealand. They are, for the great group to which they belong, birds of small size, being only as large as or slightly larger than a domestic fowl. They have a rounded, compact body, a rather short neck, and small head, while the bill is very long, slender, slightly curved, and bears the small slit-like nostrils near the tip, the latter a condition not found in any other birds. The base of the bill is covered by a hard cere and surrounded by numerous long, stiff bristles. They have relatively very powerful thighs and legs, the latter covered with scales of various sizes, and four toes, three of which are directed forward, and one, very short one, backward ; all the toes are provided with claws which are long, strong, and acute. The plumage is fluffy and quite hair-like in appearance, each feather being pointed and composed of separate loose filaments; there is no aftershaft. It was formerly sup-posed that the feather covering was continuous over the body, but it is now known that there are several small bare spaces. The wings are not quite absent, as the name implies, but are extremely aborted, consisting of a rudimentary humerus and one complete digit. There are, however, no definable wing-quills, and in fact the wings are entirely concealed by the plumage of the back; they are of course useless for flight and the birds are practically "wingless." The reduced condition of the wing is further emphasized by the fact that the sternum is without a keel. The tail is also practically concealed, there being no tail-feathers. In color the plumage is brown or grayish brown, barred across with lighter, or with each feather dark on the margins and lighter along the middle. As a structural character of importance it may be mentioned that Mr. Beddard has recently noted the presence of a very large oil-gland, which in many particulars is quite unlike that of any other bird. Instead of consisting of two lobes or sacs located a little way from the end of the tail, as in most birds, there is a single very large gland with two nipples which form the very extremity of the bird.

Habits. — Although first located near the Penguins, the structure of the Kiwis shows them to be essentially struthious, and they are now appropriately placed at the end of the Ratite series. That they constitute an ancient group is shown by the fact that two fossil forms have been found in the late Tertiary beds of New Zealand and Queensland, while several species appear to have been contemporary with the Moa, as their bones are found mingled in many places. Their nearest of kin appear to have been the Moas, but among recent birds they are perhaps nearest the Emeus and Cassowaries, since, according to Parker, they all appear to have originated from a common stem. The females are uniformly larger than the males, sometimes exceeding them by five inches in total length. They are mainly nocturnal in their habits, remaining concealed in holes and dark places during the day and coming out at dusk to feed on worms, and probably insects, which they are adept at finding by probing in moist ground and among mosses and roots. They also take a certain amount of vegetable matter such as small grass seeds, berries, and tender bits of succulent plants. Their food requirements are very large, as a pair in captivity has been found to require more than a pound and a half of meat daily. Being of a hardy disposition, they are readily kept in confinement, Mr. Rothschild having had them alive in his aviary in England for ten years or more, where they were given a large run and fed on chopped raw meat, boiled potatoes, and soaked bread. They are rather stupid birds when disturbed during the day, and as they lift their sleepy-looking heads from under the mantle of long feathers on their shoulders, they crack their bills like the snap of the fingers, and utter a few hoarse grunts of disapproval, but at night they become exceedingly active, jumping about and running with the greatest speed. They make good use of their extremely powerful legs, being always ready to kick at any object approaching them closely. In kicking they usually strike forward like an Emeu or an Ostrich, but according to Mr. Rothschild they have been occasionally observed to kick backward. When taken in the hand they never attempt to defend themselves with their bills, but if taken by the head, they use their powerful legs and sharp claws with sufficient force to rip open a dog's leg or cut a man's hand to the bone. Regarding the notes of these birds, the above-mentioned authority states that the cry of the male of the North Island Kiwi is "a somewhat hoarse, shrill whistle, often distinctly like Ki-i-wi, often shorter, more in one syllable. The female answers in a less loud, harsher and shorter, more screaming note. The young and half-grown birds also, according to Sir Walter Buller, call to each other, the male in a thinner whistle and the female in a thick, husky way. Sometimes, but rarely, a Iow crackling or grunting note is heard, probably of both male and female. When angry they hiss audibly, and when feeding make a sniffling noise with their nostrils, evidently to clear them of extraneous matter." For a nesting site they prefer a hole in a bank or under the roots of a tree, with a single rather small entrance. They may make use of a natural cavity or enlarge it and adapt it to their needs, the female at least having the power and ability to burrow for some distance if occasion demands, as Buller once found to his dismay when several which he had confined in a pen escaped in this manner. In the dryest corner of the nesting burrow they arrange a slight bed of fern-fronds and leaves whereon they deposit one or perhaps sometimes two immense eggs, which seem quite out of proportion to the size of the bird. Certain New Zealand authorities state that it is not uncommon to find a young bird a week old and a fresh egg in the same nest of the Roa. Thus the egg of the North Island Kiwi (Apteryx australis mantelli) is sometimes five and three tenths inches long by three and three tenths inches broad, while the bird itself is only about twenty-six inches in length; the egg of Haast's Kiwi (A. haasti) is said to be even larger. The eggs of the first-mentioned species weigh usually between twelve and fifteen ounces, and exceptionally as much as eighteen ounces. In color the eggs are pure white or slightly greenish gray, but soon become much nest-soiled. "The shell is very thin, the grain rather fine and totally different from that of all other struthious birds, more resembling that of the eggs of Rallidae (Rails) or of Otis (Bustard)." The male appears to take entire charge of incubating the egg (or eggs), and although the female is often found in the same hole, she has not been observed sitting on the eggs. The period of incubation is unknown, but is thought to be about six weeks, and at the close of his duties the male presents a sorry appearance, being poor in flesh and quite stupid, while the female is wide awake and full of fight, a reversion of the conditions prevailing before the egg was laid. The young are quite helpless when hatched, and are unable to stand up, but as soon as they acquire sufficient strength they accompany their parents.

The Kiwis are referred to a single genus (Apteryx), and to five and by some authorities to six forms. Rothschild, who has had a much greater number of specimens at his disposal than any previous student, recognizes five forms as follows: The South Island Kiwi (A.Australis), known locally as the Roa, which has the plumage rather light colored and the feathers of the neck soft and less bristly to the touch. The male is about twenty-three inches in length and the female twenty-seven inches, while the bill, which is a clear horn-color, is about five inches long. This species, which is confined to the South Island and adjacent smaller islands, is still quite abundant in suitable locations, but like so many of the native species, it is yearly becoming rarer. A subspecies of this, known as Mantell's Kiwi (A. A. mantelli), found only on the North Island, has the plumage darker with the neck-feathers bristly and harsh to the touch. In both these forms the feathers of the upper side are striped, whereas in the remaining species the feathers of the upper side are barred. Of these Haast's Kiwi (A. Haasti) of South Island is a very large species, the male attaining a length of twenty-five inches and the female about twenty-seven inches. It is light brown in color, with wide light bars, while Owen's or the Gray Kiwi (A. Oweni), and its subspecies, the Larger Gray Kiwi (A. O. Occiclentalis), have the plumage more grayish, with narrower bright cross-bars; the species is confined to South Island and the subspecies to South Island and the southwestern portions of North Island. The form inhabiting Stewart Island was formerly considered distinct, but proves to be only a large, brightly colored strain of australis.