Waterfowl in the Auckland Islands Duplicates and Sets Will Be Distributed to Various Taxo- Nomic Centers, in Addition to the Deposition of Primary MILTON W

Waterfowl in the Auckland Islands Duplicates and Sets Will Be Distributed to Various Taxo- Nomic Centers, in Addition to the Deposition of Primary MILTON W

most, of the collections will furnish one or more Waterfowl in the Auckland Islands duplicates and sets will be distributed to various taxo- nomic centers, in addition to the deposition of primary MILTON W. WELLER material in North America (Smithsonian Institution, Michigan State University, University of Alberta) and Department of Zoology and Entomology New Zealand (Dominion Museum, Wellington; Botany iowa State University Division, Department of Scientific and Industrial Re- search, Christchurch). As a member of the joint U. S.-New Zealand Auck- The material collected will be studied by the col- land Islands Expedition, 1972-1973, I spent 6 weeks lectors and a cryptogamic flora of the island prepared, studying the endemic Auckland Island flightless teal partly as an inventory of the flora so far as known, but (Aizas a. aucklandica) (fig. 1). Observations also were more importantly to provide data on the variability made of the sparse populations of the New Zealand of the island populations, their habitat preferences, and grey duck (Anai poecilorhyncha superciliosa) and the their relationships to other austral islands, as well as mallard (Anas platyrhynchos), which has pioneered to New Zealand and southernmost America. on the island from stock introduced in New Zealand. This work, including partial payment for the ship time, A search also was made for the Auckland Island mer- was supported by National Science Foundation grant ganser (Mergus australis) last seen in 1902. GV-2661 5.2. Major objectives of the study were to determine the biology, behavior, and adaptations of the flightless teal unique to these rugged, wooded islands. Intensive References study was made on teal populations on Ewing Island, Godley, E. J . 1965. Notes on the vegetation of the Auckland located at the northeastern part of the archipelago. Islands. Proceedings of the New Zealand Ecological Society, This island is dominated by olearia (Olearia lyalli) 12: 57-63. and rata (Metrosideros unbellata) forest. The shore- Hooker, J. D. 1847. Flora Antarctica. Vol. 1. London, Reeve line is abrupt to clifflike except for a few sheltered Bros. Imshaug, H. A. 1972. Need for the conservation of terrestrial bays. Several small unwooded areas along the coast vegetation in the subantarctic. In: Con cervation Problems in are dominated by tussock (Poa litorosa) and Mac- Antarctica (B. C. Parker, ed.). Lawrence, Kansas. Allen quarie cabbage (Stilbocarpa polaris). Observations Press, Inc. p. 229-238. also were made on nearby Enderby, Rose, Ocean, and Taylor, R. H. 1968. Introduced mammals and islands: priorities for conservation and research. Proceedings of the New Zea- French islands, on Adams Island—the most southerly land Ecological Society, 15: 61-67. of the group—and on the main Auckland Island. Figure L Male Auckland Island flightless teal, with reduced wings and dull color- : ation. b \i; • . 188 ANTARCTIC JOURNAL Methods of study included regular censuses accord- Some individuals fed at low tide on the marine algae, ing to habitat and various social groupings. Food use Porphyra, sp. Occasionally they dived in shallow water was appraised by observation and collection of a few for sea lettuce (Ulza sp.) or fed on wind-rowed sea surplus drakes. Behavior was recorded photographically, lettuce. When marine plankton accumulated in shel- and calls were taped. tered bays, teal strainer-fed on minute crustaceans. At low tide they fed by dabbing in marine algae for Results crustaceans and mollusks. At any tide level, teal probed in damp, wind-rowed kelp (4facrocystis sp.) for gam- The Auckland Island flightless teal occurs on an but marids and isopods. Some teal also fed in freshwater the main island where it is either rare or absent. Grey ponds and puddles, presumably for minute crustaceans, and mallard ducks were uncommon, but several breed- but such feeding was rare. ing records were obtained by members of the expedi- Teal are well adapted to terrestrial existence, and tion. Because of hybridization, few pure grey ducks there are no native land predators to prevent such be- were seen, and other observers suggested that mal- havior. At night, teal pairs wander through the forest, lards have increased significantly in the past 6 years. probing in loose and damp soil---apparently for ter- The Auckland Island merganser was not seen despite restrial invertebrates. Teal can he found in the forest intensive search in the rocky streams of Adams Island any time of the day, but none was collected there. and southern Auckland Island. This merganser presum- Few nests of the species have been reported, and ably fed on native trout (Galaxias balloiisi), which are only one was found during this study. A clutch of still abundant in the streams. four eggs was insulated with abundant gray down in Auckland Island flightless teal have strong pair bonds a short fern (Blechnurn sp.). The female was intensely and defend territories along seashores, where most in- broody, flushing only when someone was within 2 feet dividuals live. Excess males group in favored feeding of the nest, and returning to the nest in spite of the areas. Unpaired females also occur in these groups, but presence of man. whether they are nonbreeding yearlings or unsuccessful The major predator appears to be the brown skua breeders is not clear. Some teal occur at stream mouths (Ca/haracta skua), and remains of several adult teal or in freshwater near the sea (fig. 2). They also occur were found at skua nest sites. No direct attacks on inland in soggy tussock fields, but their relative abun- teal were seen, but teal obviously feared skuas and dance, breeding status, and permanence in such areas were alert constantly to their activities. Teal sought pro- is uncertain. Most individuals are coastal residents and tection by running either into petrel burrows or to depend on the sea for their food. water, where they remained as long as a skua was Teal were broadly adapted to a great variety of foods. perched nearby. Teal rarely slept in the open and I Figure 2, Auckland Island flightless teal in a freshwater pool along the coast of Ewing Island. July-August 1973 189 then did so only when perched on, rocks standing in vergence would provide additional information concern- water. Teal rested in grass and torbs or went into ing the distribution and movement of organochlorine caves or petrel or rabbit burrows during the day. They compounds in the southern hemisphere. The New Zea- remained in the open only when feeding actively and, land Department of Lands and Survey and the Wildlife where possible, fed under a canopy of trees. Branch, Department of Internal Affairs, with the as- Only two broods were seen—both in tussock areas. sistance of the U.S. National Science Foundation, con- One downy young was in a small freshwater pool with ducted a 3-month expedition to the Auckland Islands only a male nearby. Two young were seen with a during the austral summer, 1972-1973, to investigate female in dry tussock, but a male was about 40 feet the distribution, population, and behavior of the flora away. Of four other broods reported by expedition and fauna of these subantarctic lands. In all, 27 scien- members, three were in wet tussock and forbs or tussock- tists took part, with five Americans participating from rimmed pools, and one was in a tidal pool. Young December 8, 1972, to January 14, 1973. I accom- obviously are very secretive, presumably in response to panied the expedition to obtain wildlife samples for the pressure of skuas. pollutant analysis. The Auckland Island flightless teal is an inconspicu- The Auckland Islands group, centered at 50040S. ous bird. Except when feeding at sea, teal can be 166°05E., consists of two large islands (Auckland abundant but hidden from view in grass and forbs. Island and Adams Island) and several smaller islands. Whether they feed actively at sea at night is unknown. The terrain is rugged and the climate inhospitable, with The status of the species seems secure presently be- strong winds and frequent rain. The vegetation, lush cause of its wide distribution on all but the main island. at low elevations, varies from dense rata forest (Metro- However, the absence of the species there where it once sideros umbellata) at sea level to tussock grass (Chi- occurred suggests that the presence of introduced cats onochia sp.) and fell field at high elevations. The and pigs may be a factor in their disappearance. It is, islands have been inhabited by man only briefly, but therefore, vital to prevent further spread of these two introduced animals are apparent and have had a marked introduced mammals on the outlying islands if the effect on the vegetation and nesting birds on some of Auckland Island flightless teal is to survive. the islands in the group. Nevertheless, the Aucklands This work was supported by National Science Foun- constitute a major seabird breeding ground, with 17 dation grant GV-21491. species of albatrosses and petrels recorded as nesting there. The large variety of seabirds permits a choice of species for sampling pollutant levels, considering dif - Pollutants in the Auckland Islands ferences in feeding habits and in distribution. The Auckland Island shag (Phalacrocorax colensoi) and the redbilled gull PETER G. CONNORS (Lai-us scopulinus), for example, are relatively sedentary, remaining near their nesting areas Bodega Marine Laboratory and therefore indicating levels of pollutants in their University of California food species near the Aucklands. The wandering alba- tross (Diomedea exulans), on the other hand, is ap- Evidence has been accumulating that agricultural parently circumpolar at these latitudes in its annual and industrial organochiorine compounds, notably DDT movements, and the sooty shearwater (Puffinus griseus) compounds and polychlorinated biphenyls (PCB), have ranges as far north as Japan and the western United become widespread pollutants found throughout the States during its winter migration (Alexander, 1955).

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