Paradise Shelduck 69

Some notes on the Paradise Shelduck MAURICE FITZGERALD In WILDFOWL 19, Dr. Kear, comment­ chicks were able to fly the whole family ing on D. S. Wintle’s article on Versicolor departed— presumably to the tribal home Teal, said that his ‘ observations show how at Rotomahana— before the adults started much of scientific interest can be achiev­ to moult. ed by an aviculturist with even a small On one occasion, when the clutch of collection of wildfowl. We hope that eggs was still fresh, ten Indian Runner others will be encouraged to study the eggs were given the birds in exchange for behaviour of their birds in a similar their own. These were duly hatched and w ay’. I was so very fortunate to be per­ reared on the lagoon. About the end of sonally encouraged by Dr. Kear on her November the adults, who apparently felt all too brief visit to my home in New the urge to leave, spent days of anxious Zealand in January 1969. I then deter­ effort to teach their family to fly. In the mined to place on record my perhaps end the parents left, leaving the near unique experience of the Paradise Shel­ flightless Indian Runners on the lagoon. duck Casarca variegata. As my 86th mile­ The following year the pair returned stone is just around the comer, I thought to the same area but selected a new nest­ I had better get on with the job. ing site. The male died as a result of M y first aviary was a disused W.C. bashing into a farm wire fence, and the in the backyard of our Wellington home nest was destroyed. Within a short while during the 1890’s. It was not until I re­ the female made friends with a tame turned from the First World War and pinioned male in the farmer’s garden and acquired a home of my own that I was went to nest in another position. Some­ able to ask the Department of Internal one robbed that nest and frightened the Affairs to arrange for the Southland bird away. All that day she flew over the Acclimatisation Society to send me half farmhouse shouting what were understood a dozen Paradise Ducks. When they arriv­ to be curses at a husband who had failed ed they were in full moult, showing not to warn her of the approach of strangers. a single feather on their heads. On mak­ She vanished for a day or two but re­ ing enquiries about sexing I was informed turned with a new follower and is believed by those who should have known better to have had a third nest that season, that it was impossible to sex the breed though I have no evidence one way or the until after their first moult. In due course other. This experience enhanced my scep­ they all turned out to be males. They ticism for assertions that suchlike birds must have been adults too. This ex­ mate for life. It seems probable that the perience probably challenged me to get young female is first to lay claim to a at the facts in my own way, as I did. nesting territory and that (as I have heard it said) she selects a mate from her reti­ Breeding nue. Next season it is she who is first on M y experience with their nesting habits the spot to lay claim to her established is limited to the mob which is centred rights and, if he be there, it is her mate on Rotomahana Lake near Rotorua where of last season who feels that the other they assemble during December to go males are intruders and acts accordingly. through their annual moult. They dis­ Several old writers have asserted that perse over the pumice plateau as far north both sexes share the duty of incubation. as Tokoroa, 34 miles away, at breeding I have seen no evidence of this. M id- time. Usually the parties to arrive com­ afternoon the female comes off her eggs prise one female accompanied by several and flies to a favourite spot for a feed, a males. Within a few days just one pair thorough bath and preen. On the way remain— probably the lady o f last year there she is joined by her mate who and her old mate, if he be still as fit as spends most of the day grazing on a high ever. Years of observation lead me to place overlooking the area of the nest. The believe that all pairs of that clan com­ pair then circle their territory a few times mence laying on the same day. One pair before the female drops down to the nest which nested year after year in a rock and the male returns to his observation cavity overlooking a stream quite close post. to a farm house always took their newly hatched brood to a nearby lagoon formed Our Paradise does not form crèches as by damming the stream for the purpose the Common Shelduck Tadorna tadorna of generating electric power. They were appears to do, but one experience of mine under constant observation. When the is worth relating here. A Muscovy 70 Wildfowl hatched out five or six Paradise eggs in a Broken wing display small chicken coop. When they were Dr. Kear, when walking along the mar­ about three days old the chicks got out gins of shallow water on which parents during the night or early morning. I and ducklings were floating, witnessed the found them accompanying a tame Para­ broken wing display by the male who dise female who had never had a mate came ashore and tried to lure her away nor ever laid an egg. I promptly released landwards. She sought my opinion as to the mother Muscovy but the ducklings how that habit could be inherited in a stuck to the maiden lady who success­ land that never had endemic mammals. fully reared the lot. I have never experienced such a sight, probably because my approach to young Development of sex differences broods has either been where the birds The adult male, when showing annoyance were near farmhouses and accustomed to at some intruder, or even when greeting human beings who took little notice of his keeper, holds his head close to the them, or along small stream beds run­ ground with bill horizontal, and rushes ning along narrow cuts through the forward honking in a deep voice. The pumice plateau so that any dry-land an­ female, when calling, holds her head tics by the male would be out of my high and flicks her bill up at each call. vision. There would be no point in the The male ducklings, when only a few days act if I were arriving by row boat. Other old, adopt that ‘ hangdog’ stance of their people such as Buller, Guthrie-Smith and fathers when running about. I once sorted Douglas have reported seeing the display a dozen babies on that basis— giving six, performed on land, and Mr. Explorer believed to be males to one foster bantam Douglas’ dogs seem to have been the and the remainder to another hen and cause of some ‘ predator distraction ’ be­ kept the two lots apart. The result was haviour. If the broken wing behaviour be 100% right. an inherited characteristic it may be trace­ Charles Darwin was very struck with able to the extinct eagles which once in­ the unique manner in which this bird habited this land. Dr. Kear is inclined to completely reversed sexual colouration. think the large extinct rail Aptomis might First feathers appear alike in both male be responsible, but I feel that this bird and female— mainly dark grey body with wasn’t large enough. Human beings have clear black head and neck. The males re­ inhabited the land for nigh on 2,000 main like that but some will have two years, though few, if any, were in the or three small white feathers among the mountainous parts of the south island black on their heads, which used to be which is the principal habitat of the Para­ very misleading. The females, while still dise. In any case, man is not fooled into flightless, begin to change to their adult thinking that the bird is really injured, colours of warm brown with pure white he merely realises that it has young; so head and neck. With some clutches the in relation to him, the display is more females show a slight tinge of brown on likely to have been a disadvantage and breast as soon as those feathers come out quickly eliminated. Wild pigs, which cer­ of the quills— age about five or six weeks. At seven or eight weeks old the female tainly might take young, have been here head, which was black at first, shows for less than 200 years. There is the pos­ white feathers against the bill. Within a sibility that Paradise learned the device week this is a complete white band about from experience and that those o f today fth of an inch wide and rings of white have learned by precept. That would rule are beginning to show around the eyes. out heredity. When approaching a brood At two months the head is about 50% by boat the parents will yell an alarm white and at six months the head and and skitter along the water in order to neck are completely white. Laidlay, who induce the chicks to dive or hide in near­ has bred these birds, tells us that the females eclipse to the extent of reverting by water weeds— something they are con­ to the grey body at moult. I have occa­ stantly doing when harrier hawks, or even sionally observed a tendency towards that the predacious Black-backed Gulls, are behaviour. about.

M. E. W. FitzGerald, O.B.E., Riverlea Road, Hamilton, New Zealand.

While WILDFOWL 20 was in press the Editors received the sad news that Mr. FitzGerald died on 4th August 1969.