The Owl That Fell from the Sky (6 page)

The egg was resting on an acid-free cushion. The outer surface was pale brown, with some marks and stains. It was sound in many areas, with clearly marked pores, but worn smooth elsewhere. Some pieces had been glued back along the broken edge but about forty percent of the egg was missing. The damage was a bonus as I was able to measure shell thickness at several points around the break using vernier callipers, an instrument that measures the internal and external dimensions of an object to a high degree of accuracy.

I also weighed the egg, and inspected its outer surface with a magnifying thread-counter to see the slit-like pores and record their maximum length.

The thickness of the egg's shell was a surprise: the largest moa egg might be expected to have the thickest shell, but in fact it was only 1.2 to 1.3 millimetres. The thickest known shell—at about 1.8 millimetres—is that of a smaller moa egg in Otago Museum; it was found at the Shag River Mouth archaeological site on the South Island's east coast, about 500 kilometres south of Kaikoura. This egg is likely to have belonged to the heavy-footed moa, whose stocky proportions are indicated by its Latin name,
Pachyornis elephantopus
. It seems the tall, slender giant moa could get by with thinner eggshell than its shorter, dumpier heavy-footed relation.

 

Jammit, the Ōkārito kiwi

On the road to the tiny settlement of Ōkārito in Westland, a kiwi was hit and killed by a vehicle in August 2002. Its body was placed in a Department of Conservation freezer.

This bird had hatched in February 1999 in the South Ōkārito Forest. Later that year it had been caught and given a metal ring numbered R-55376. A DNA sample had disclosed that the kiwi was female and she had been given the name Jammit. She had been still immature and living with her parents when she died at the age of three and a half. Ōkārito kiwi are potentially long-lived, but in this sad case there was a small consolation, for Jammit was destined for a place in taxonomic history.

Kiwi are strange birds with a catalogue of remarkable features. The smallest of the ratites, a group of southern hemisphere birds that includes the emu and ostrich, they have unusual body proportions. Their legs, relatively large and muscular, make up about a third of their total body weight because their wings are only tiny vestiges. Their undeveloped flight muscles make their bodies cone-shaped—so much so that when the South Island brown kiwi was described and named in 1813, on the basis of one preserved specimen that had reached Britain the previous year, some thought the authors of the description had been the victims of a hoax.

Adult kiwi weigh between one and three and a half kilograms, depending on the species and sex: the females are larger and about twenty percent heavier than the males. The bird's plumage is loose and hair-like. There are no prominent tail feathers, and the tiny wings are hidden in the body plumage. Around the face there are bristle-like feathers that transmit a sense of touch. The external nostrils open near the end of the long bill, which is slightly curved downwards, and this position of the nostrils is unique. Unlike most birds, kiwi have a good sense of smell. As they probe in the soil for food they snuffle noisily: they are forcefully exhaling to clear their nasal passages.

Kiwi inhabit forest and scrub from sea level to the subalpine zone and are predominantly nocturnal. They eat fruits, berries, insects, earthworms and other invertebrate animals they find on or near the forest floor or by probing in soft earth. They form a family of their own—the Apterygidae—that is found only in New Zealand. Their nests are in hollow logs, rock crevices or underground burrows that they excavate. The female produces one or two (very rarely three) eggs. The egg is very large relative to her weight and contains a high proportion of yolk. It is incubated for a long time—about eighty days—and the resulting chick is very advanced, in fact a miniature version of the adult.

Once found throughout the country in suitable habitats, kiwi have disappeared from many parts of New Zealand and continue to decline everywhere on the mainland, except in places where there are interventions to reduce predation by rogue dogs, introduced stoats and other mammals. In the long term these birds may survive only in predator-controlled, specially fenced sanctuaries—known as “mainland islands”—and on predator-free offshore islands.

Until recently there were thought to be three species: brown kiwi (
Apteryx australis
), little spotted kiwi (
A. owenii
), and great spotted kiwi (
A. haastii
). The brown kiwi has brown plumage with darker lengthwise streaks, whereas the spotted kiwi have greyish plumage with paler crosswise streaks: from a distance they appear vaguely spotted.

In the last two decades, molecular biology has revolutionised taxonomy and classification—the process of defining boundaries between species and grouping the species in logical ways. The classification of birds has benefited greatly. Researchers can now use tissue samples—from either living birds or museum specimens—to determine the DNA composition of segments of selected genes. The chemical sequences of these samples are then compared to obtain objective information on the degree to which they differ. This becomes an additional characteristic, and a very important one, to weigh up alongside traditional characteristics in considering where species boundaries lie. The work has tended to establish ever finer differences: there is now a trend for more and more species and subspecies of birds to be recognised.

Biologists and rangers who studied brown kiwi in the wild at Ōkārito from the 1950s thought these birds were somewhat different from other South Island brown kiwi. Recently, DNA studies confirmed this. In 2003 a paper in the international journal
Conservation Genetics
recommended that the North Island, South Island and Ōkārito populations of the brown kiwi should each be regarded as separate species. This is not surprising: since kiwi are flightless their ability to move around the country and intermingle is limited. And given their very long evolutionary history isolated in New Zealand, it is no surprise that DNA studies of brown kiwi have shown up significant geographic variations.

 

 

Unfortunately, the authors of the paper did not stop at their excellent recommendation that the Ōkārito kiwi be recognised as a distinct species. They went on to coin a name for it, stating that “a new species,
A. rowii
, should be erected”, rowi being a Māori name sometimes used for the Ōkārito birds. The authors may have thought this was all that was needed to describe a new species, or they may have been merely suggesting the sort of name that could be used. Whatever the case, they provided a name but did not meet other requirements of the International Code of Zoological Nomenclature.

The Swedish botanist Carl Linnaeus developed the system of naming organisms used today. Each species has a two-part Latinised name, such as
Homo sapiens
or
Tyrannosaurus rex
, rendered in italics to set it apart from ordinary text. The first part, always with an initial capital letter, is the name of the genus, a parallel to the surname in families because it may be shared by several entities that belong to it. The second part is the “specific” name which, in tandem with the generic name, makes a combination that uniquely names the species of animal.

Our current system of animal names is decreed to have begun with the tenth edition of Linnaeus's book
Systema Naturae
, published in Sweden in 1758. Over the centuries, as might have been expected, naming has become horrendously complicated. Many of the species we recognise today have been unwittingly named numerous times before. In September 1895, at a meeting in Leiden in the Netherlands, an International Commission on Zoological Nomenclature was formed to regulate animal names. The commission deals just with names, not with the working out of species and other taxonomic units. Its aim is to maximise stability and universality of animal names, except where taxonomic judgement runs counter. There is no reliance on case law; instead rules are applied directly, and exceptions require an individual ruling from the commission. The rules of nomenclature—for example, that the oldest validly published name of a species has priority over later names—are set out in a code to which zoologists throughout the world are expected to adhere. The names of plants and micro-organisms are governed by parallel codes.

The code has many requirements. For instance, if a new animal is being named a single preserved specimen must be designated so it can “carry” the new name and be a point of reference in any future disputes or uncertainty. This is called the holotype. It is recommended that these and other kinds of “type specimens” be lodged in publicly owned museums, where they can be consulted on request and treated as the property of science internationally. These specimens, of which there are millions around the world, are among the most important held by natural history museums.

The 2003 kiwi article neither nominated a type specimen, nor stated an explicit intention to name a new species. This made the new name
Apteryx rowii
a
nomen nudum
, or “naked name”, invalid for taxonomic purposes. The name was also badly formed. In Latinised specific names the –
ii
ending is used to honour a male person: “rowii” suggests the animal is named after a Mr Row or Rowe. When using a Māori name of an animal as a specific name, it is a “noun in apposition”. Hence the correct form for a bird called the rowi is simply “rowi”.

The invalid name
Apteryx rowii
was repeated in an article in the
New Zealand Listener
in July 2003 and began to appear on internet pages. There was a prospect of it becoming widely used. At the time, a committee of the Ornithological Society of New Zealand had begun a ten-year project to prepare a new checklist of New Zealand birds. Several members of the committee studied the issue and we agreed to publish, as quickly as possible, a valid description of the new kiwi with a properly formed name. We got this out in December 2003 and, happily, the correct name
Apteryx rowi
has been followed by everyone since.

In the formal description of the Ōkārito kiwi, we had to designate type specimens. The problem was that no museums had any specimens of the bird, apart from a pre-1945 headless specimen at Canterbury Museum. It seemed that in recent times all bodies of kiwi that died accidentally at Ōkārito had been either sent for post-mortem examination by vets, after which the bodies had been destroyed, or given to local Māori groups so the feathers could be used for making cloaks.

Some inferior, damaged, partial specimens were hurriedly rustled up: they could be used as secondary “paratypes” in the species description. And then luckily, at the crucial time, one intact kiwi did become available—Jammit. She was mounted by a taxidermist for Canterbury Museum.

 

Leo Cappel's albatross diorama

On the natural history floor of the Auckland War Memorial Museum stands a magnificent diorama of a pair of large albatrosses in courtship display at their nest on a subantarctic island south of New Zealand. To one side a skua, dwarfed by the albatrosses, has brought food to its chick. The diorama is technically complex and artistically superb. A large viewing window, 2.4 metres wide, hides the edges of an even larger dome about 4.5 metres in diameter, the concave interior of which forms the back of the diorama. The birds occupy the foreground; a scenic landscape is painted on the inside surface of the dome.

Dioramas are a marriage of science and art: scientific accuracy in the composition of the scene and choice of elements is married to artistry in the background painting and the pose and set-up of the stuffed animals and the elements of their habitat. In any diorama, the tie-in between the background dome and the foreground is critical. In the albatross diorama, this junction is masked by the careful placement of tussock grasses, and the pretence that the land slopes away from the viewer towards the sea. The net effect is a perfect illusion of a natural scene with broad and distant horizons. The glass is angled to minimise reflections.

When the diorama was built, the albatrosses were considered to be wandering albatrosses. Recently, this “species” has been broken up into several species and subspecies that breed on different islands. We don't know which islands the diorama birds came from, but they are probably what we now call Antipodean albatrosses,
Diomedea antipodensis
, which breed on the Antipodes Islands, Campbell Island and Auckland Islands.

Wandering albatrosses and their near relatives are the so-called “great albatrosses”—the world's largest seabirds. Their wingspan, at 3.5 metres, is the greatest of any bird's. These albatrosses range widely in the southern oceans, breeding at various islands. They have difficulty taking off from land, so they nest near a rise where winds will help them fly.

Antipodean albatrosses can live for as long as fifty years. To attract and retain a mate, they perform complex ritualised courtship displays, accompanied by beak-rattling and vocalisations that climax in a piercing scream. Having found a mate they stay with them for life. A single egg is laid in summer. Both sexes take turns incubating it for what is the longest incubation period of any bird—often more than eighty days. The parents brood and feed the nestling and it fledges the following summer. This is such a long breeding cycle that the parents breed only every second year.

Southern skua,
Catharacta antarctica
, are related to gulls and breed on subantarctic islands. While breeding they mainly eat eggs and chicks robbed from other birds' nests, and smaller seabirds that they catch and kill.

Auckland Museum's albatross diorama was built in 1970, but its birds go back to the 1930s. Up until 1929 the museum occupied a building in Princes Street. Here most of the collection was on display and the galleries were cramped. When it moved to a spacious new building on a hill in Auckland Domain, the modern approach of showing just a choice selection of the collection could be followed: less clutter and more style. There was now an opportunity for an entire gallery devoted to ornithology, and a Hall of New Zealand Birds was developed on the natural history floor at the front of the building.

The initial fit-out was a bit thin and, in the years that followed, displays were gradually augmented and improved. In 1933 a free-standing glass case was installed in the centre of the hall for a new exhibit featuring a pair of albatrosses at their nest. The male albatross, with wings outstretched, had been obtained in November 1931 by the chief officer of a passenger ship, SS
Marama
, in the Tasman Sea. The
Marama
was a Union Steamship Company boat, built in 1907 at Greenock in Scotland. It had served as a hospital ship in the First World War and continued in maritime service until 1937. Probably the albatross was found on board dead or injured after striking the ship by accident: it is unlikely any sailors would have shot an albatross.

The female albatross had been found near Dargaville, north of Auckland, in June 1932. It had probably washed up, freshly dead, on a local beach. Both birds would have been mounted by Auckland Museum's taxidermist, Charles Dover. In his twenty-four years at the museum, Dover prepared hundreds of mounts and study-skins. He was also a skilled model-maker; during the war he would produce models of tropical fruits for use in teaching survival skills to Royal New Zealand Air Force personnel before they were sent for service in remote Pacific islands. To the same end, the museum in 1943 produced an illustrated booklet,
Food is Where You Find It
–
A Guide to Emergency Foods of the Western Pacific
, for castaway airmen.

In 1960 the museum building was doubled in size by an extension. Galleries were reorganised and a new bird gallery planned at the south end of the natural history floor. In 1970 the albatrosses were recycled into the diorama to provide a focus at the entrance to this new bird hall. The plaster dome was designed, built and painted, and the diorama's contents assembled, by the museum's preparator, Leo Cappel. Preparators are museum staff who build models and displays. A Dutch immigrant who had joined the staff in 1964, Cappel was skilled in all forms of this work, from backdrop painting and model-making to taxidermy.

The albatross diorama was not the only one: there were twelve dioramas of various sizes in the new bird gallery. The largest, seen straight ahead on entering the gallery, showed forest birds on a dry kauri ridge on Little Barrier Island. To the left, past some foliage, visitors could see the Hen and Chickens Islands on the horizon. Cappel had developed new techniques for the preservation of leaves, and in 1973 would publish a popular book,
A Guide to Model Making and Taxidermy
.

Sir Arthur Galsworthy, British High Commissioner to New Zealand, presumably stood in front of the albatrosses when he opened the bird hall in April 1972. This highly successful gallery lasted until 1996, when the area was assigned to back-of-house storage and workspaces. The albatross diorama was to be replaced by something new, but this never happened. Today it has fresh importance as the only large, dome-backed diorama to survive the modernisations of the 1990s. Its technical complexity and artistry were unmatched by any of the new simplified habitat reconstructions, and in 1999 the preparator of the day, David Weatherley, cleaned the albatrosses and remodelled the groundwork.

There is a world crisis in museum taxidermy and concerns it may be a dying art. Essentially it is a western tradition, with no great strength or history elsewhere, and opportunities for training new museum taxidermists have steadily declined. While countries outside the west are building big new museums with natural history displays, the standard of taxidermy is often frighteningly low. Meanwhile, many western museums have destroyed their historic dioramas in successive waves of modernisation.

The pendulum may be about to swing again: there are signs of a renewed interest in historic taxidermy. Leading the way has been the American Museum of Natural History in New York, with a multi-million-dollar restoration of its magnificent diorama halls, where large stunning displays depict habitats around the world. If you cannot make it to New York just at the moment, next time you are in Auckland Museum study the forty-year-old albatross diorama. Have a look at some old friends you may have seen before. Admire the illusion of their cunningly contrived setting and wish them luck for the next forty years and beyond.