Order ANSERIFORMES.] 



[Family ANATID.E. 



NESONETTA AUCKLAND ICA. 



(AUCKLAND-ISLAND DUCK.) 



Nesonetta aucklandica, Gray; Buller, Birds of New Zealand, vol. ii., p. 263. 



I have had an opportunity of examining a large series of skins of the small flightless Duck, 

 collected by Mr. H. H. Travers at the Auckland Islands, the group to which this species is strictly 

 confined. The sexes in the adult state do not differ much from each other, both exhibiting the 

 delicate reflections on the plumage of the upper surface ; but the male may be distinguished by 

 its darker head and neck, by the black under tail-coverts, and by a greater abundance of vermicu- 

 lated markings on the sides of the body. The young male, as I discovered, has exactly similar 

 plumage to the adult female, the head being of the same brown colour as the body, with a paler 

 throat. There is likewise an absence of black on the under tail-coverts. The adult plumage is 

 probably assumed in the second year. 



As with the insects of Madeira, mentioned by me in the Introduction, so with this Duck : 

 long disuse has rendered the wings useless for purposes of flight ; but, as if to compensate for 

 this, the species possesses the unusual faculty of being able to climb — an accomplishment which 

 no doubt would be of far more advantage to the bird in its rocky habitat, surrounded by the ocean, 

 than the power of flight. I made the discovery by the purest accident. The late Captain Fairchild, 

 on the return of the ' Hinemoa ' from one of her visits to the Auckland Islands, presented me with 

 a living pair, which I immediately placed on the Papaitonga Lake, in the hope that they might 

 breed there. I afterwards purchased a pair from one of the crew, and, being desirous of sending 

 these to Europe, I placed them in a wire enclosure, over three feet high, in a secluded part of my 

 garden. I noticed that they at once commenced to scale the perfectly upright netting, falling 

 back into the yard as they neared the top of the fence. Never supposing that they would get over 

 the fence, I left them in the enclosure. In the morning the male bird, being the more robust of 

 the two, had made its escape, and I had little hope of ever seeing it again, there being much close 

 covert in the garden. A few evenings afterwards I found both birds again in the yard, the 

 fugitive having evidently climbed back into the enclosure for the purpose of sharing his 

 mate's food. In the morning he had disappeared again. This continued for about ten days, the 

 bird (which is semi-nocturnal in its habits) skulking and hiding during the day, and coming back 

 in the evening to share the food. When I was ready to ship the Ducks I had simply to visit the 

 enclosure after dusk, and then, catching them without difficulty, they were cooped and despatched 

 to London by the B.M.S. ' Tainui.' 



My captive birds never made any attempt to use their wings, although they had every 

 opportunity. Those who have seen the bird in its native home state, however, that it does 

 perform a fluttering flight for a few yards along the surface of the water.* 



* Dr. Hans Gadow writes (< Nov. Zool." ix., p. 170) : « I have come to the conclusion that Nesonetta is in the act 

 of diminishing its wing-area by reduction of the number and size of its primaries, from the examination of three spirit 

 specimens and six skins. None of the specimens are in moult. ... The right and left wing are not always 

 symmetrical, there being specimens with ten good functional primaries on one side and with only nine on the other wing, 

 or with nine and eight functional quills, or with nine, or lastly with only eight functional quills on either wing. . . . 

 Perhaps not every individual does undergo this process of reduction which attacks successively the eleventh quill, which 

 is now almost universally obsolete in birds, then the tenth, and now in Nesonetta, even the ninth quill. In this respect 

 Nesonetta, now unfortunately on the verge of extermination, exhibits a most interesting parallel with its equally unlucky 

 contemporary the Flightless Cormorant \Phalacrocorax harrisi of the Galapagos Islands] ." 



