2 Birds of the Auckland Islands, New Zealand subantarctic COLIN M. MISKELLY* RODNEY B. RUSS Museum of New Zealand Te Papa Tongarewa, Strannik Ocean Voyages Ltd, PO Box 9172, PO Box 467, Wellington 6140, New Zealand Christchurch 8011, New Zealand GRAEME P. ELLIOTT ROWLEY H. TAYLOR 549 Rocks Road, Nelson 7011, New Zealand 13 Templemore Drive, Richmond 7020, New Zealand GRAHAM C. PARKER ALAN J.D. TENNYSON KALINKA REXER-HUBER Museum of New Zealand Te Papa Tongarewa, Parker Conservation, 126 Maryhill Terrace, PO Box 467, Wellington 6140, New Zealand Dunedin 9011, New Zealand KATH J. WALKER 549 Rocks Road, Nelson 7011, New Zealand ABSTRACT: The Auckland Islands are the largest island group in the New Zealand subantarctic region, and have the most diverse avifauna, including eight endemic taxa. We present the first comprehensive review of the avifauna of the Auckland Islands, based on a database of 23,028 unique bird records made between 1807 and 2019. At least 45 species breed (or bred) on the islands, with a further 77 species recorded as visiting the group as migrants, vagrants, or failed colonisers. Information on the occurrence of each species on the different islands in the group is presented, along with population estimates, a summary of breeding chronology and other reproductive parameters, and diet where known. The frequency at which 33 bird species were encountered during visits to the seven largest islands is compared graphically to facilitate comparison of each island’s bird fauna in relation to habitat differences and the history of introduced mammals. Disappointment Island (284 ha) is the least modified island in the group. However, it lacks forest, and so has a very restricted land bird fauna, lacking ten species that breed on other islands in the group. Auckland Island (45,889 ha) is the only major island in the group where introduced mammals are still present. As a result, it also has a depauperate bird fauna, with at least 11 species completely absent and a further seven species reported at lower frequencies than on the next largest islands (Adams and Enderby Islands). Miskelly, C.M.; Elliott, G.P.; Parker, G.C.; Rexer-Huber, K.; Russ, R.B; Taylor, R.H.; Tennyson, A.J.D.; Walker, K.J. 2020. Birds of the Auckland Islands, New Zealand subantarctic. Notornis 67(1): 59–151. KEYWORDS: Auckland Islands, birds, biogeography, breeding, New Zealand subantarctic, ornithology, vagrant Received 28 May 2019; accepted 15 July 2019 *Correspondence: [email protected] Introduction population estimates for the few species where this is known. Comparisons are made between The Auckland Islands (Maukahuka/Motu Maha, the bird faunas of the seven largest islands in 50°44’S, 166°05’E; Fig. 1) are the largest and bio- the group, and between the Auckland Islands and logically most diverse island group in the New other island groups in the New Zealand subant- Zealand subantarctic region (Russ & Terauds arctic region. 2009). However, there is little published infor- mation summarising the bird species recorded Physical description of the from the group, or the differences in bird commu- Auckland Islands nities between islands within the group (Oliver The Auckland Islands are the rugged, eroded 1955; Turbott 2002; Shirihai 2008). The history of remnants of Early to Middle Miocene basaltic vol- ornithological research on the Auckland Islands canoes, reaching heights of 705 m above sea level was summarised by Miskelly & Taylor (2020 – (a.s.l.) on Adams Island and 659 m a.s.l. on Auckland Chapter 1 in this book). Pioneering information Island, and with sheer sea cliffs reaching 500 m was gathered during three main phases: 1840 a.s.l. along their exposed southern and western (three brief visits by northern-hemisphere-based coasts (Adams 1983; Quilty 2007; Scott & Turnbull exploring expeditions), 1888–1929 (even shorter 2019). Covering c. 56,750 ha, the islands extend visits by scientists and naturalists travelling on 51 km north to south, with the highest peaks New Zealand government steamers that were around Carnley Harbour in the south (Fig. 1). searching for shipwreck survivors and main- There are six islands that exceed 15 ha, and about a taining castaway depots), and 1941–45 (natural- dozen smaller islands. The islands in Port Ross are ists enlisted in the New Zealand military who low lying, with a maximum height of 48 m a.s.l. were based on the islands as part of the ‘Cape (on Rose Island). Expedition’ to watch for enemy vessels). Much Below 500 m a.s.l., the gentler slopes are information was gathered subsequently by New blanketed with peat up to 10 m thick, with skeletal 61 Zealand government and museum research expe- or non-existent soil on the highest peaks and ditions in 1954, 1962–63, 1966, 1972–73, 1978, and ridges (McGlone 2002). The more sheltered north 1989, and bird records (mainly unpublished) have and east coasts of Auckland Island (45,889 ha) accumulated rapidly during the more regular eco- are fringed with a narrow (c. 50 m wide) belt of tourism and research visits that have occurred in southern rātā (Metrosideros umbellata) forest, the austral summer since the early 1990s (Miskelly 6–14 m tall, which grades altitudinally into shrubland & Taylor 2020 – Chapter 1). (dominated by rātā, Dracophyllum longifolium, Soon after the Second World War, Oliver (1955) D. cockayneanum and Myrsine divaricata), then commented that ‘The general account of the birds through Chionochloa tussock grassland to upland [of Auckland and Campbell Islands] has not tundra and fellfield (Godley 1965; Johnson & yet been written’. Several accounts of Campbell Campbell 1975). At sites inaccessible to browsing Island birds appeared over the following 14 years mammals, dense megaherb fields dominated by (Westerskov 1960; Bailey & Sorensen 1962; Kinsky Anisotome, Stilbocarpa, and Pleurophyllum species 1969), but the Auckland Island story has remained grow more than 1.5 m tall in nutrient-rich coastal untold until now. We summarise information on sites, and in more-stunted form in upland tundra. all breeding, migrant, and vagrant bird species Adams Island (9,693 ha) has similar vegetation recorded from the Auckland Islands, based on a to the main island, but with extensive Chionochloa comprehensive database of bird records derived tussock meadows on the southern flanks, and from both published and unpublished sources. Dracophyllum is more prominent in the coastal Information on breeding chronology and diet rātā belt (Elliott et al. 2020 – Chapter 3 in this are summarised where known, along with book). Disappointment Island (284 ha) to the west lacks forest, and is almost entirely covered in tall Poa litorosa and P. foliosa tussock grassland and FIGURE 1 (OPPOSITE). Map of the Auckland Islands, megaherb fields dominated by Anisotome latifo- showing places named in the text. lia (Walker et al. 2020 – Chapter 5 in this book). Lost Gold: ornithology of the subantarctic Auckland Islands The vegetation differs on each of the three larger Human history, and the presence of islands in Port Ross (R.H. Taylor 1971; Wilmshurst introduced mammals et al. 2015). Enderby Island (695 ha) has an extensive Evidence of early Māori has been found on Enderby stand of rātā forest on the southern and eastern Island (Anderson 2005, 2009); however, the islands slopes, with an adjacent belt of Ozothamnus vau- were uninhabited when discovered by Europeans villiersii shrubland along the low central ridge. The in 1806. The discoverer (Abraham Bristow) north-western plateau of Enderby Island is covered returned the following year, releasing pigs (Sus with an almost pure stand of the lily Bulbinella scrofa) on Enderby Island and possibly Auckland rossii, with Poa litorosa tussock grassland recov- Island, and precipitating several decades of intense ering around Sandy Bay and on the north-eastern harvest of New Zealand fur seal (Arctocephalus headlands (R.H. Taylor 1971; French et al. 2020 – forsteri) skins (R.H. Taylor 1968; Prickett 2009). Chapter 4 in this book). Rose Island (78 ha) has a Cats (Felis catus) and house mice (Mus musculus) small patch of rātā forest on the south-east coast, were established on Auckland Island by the time with most of the island covered in tall Poa litorosa the first naturalists visited in 1840 (Russell et al. grassland (Godley 1965; R.H. Taylor 1971). Ewing 2020 – Chapter 6 in this book). The sealers and Island (58 ha) is almost entirely covered by the whalers were followed by short-lived settlements tree daisy Olearia lyallii (introduced from southern of Māori and British at Port Ross 1842–56 (Fraser New Zealand), with a small area of rātā forest in the 2014), resulting in 50 years of intense hunting centre (Wilmshurst et al. 2015). pressure on birds for subsistence (Miskelly & Situated between the subtropical front and the Taylor 2020 – Chapter 1). The settlers also intro- Antarctic convergence, the islands are exposed to duced farm stock (including further pigs, cattle Bos persistent gale-force winds predominantly from taurus, and sheep Ovis aries), rabbits (Oryctolagus the westerly quarter (de Lisle 1965). Year-round cuniculus), and dogs (Canis familiaris) (R.H. Taylor weather records were collected at Port Ross and 1968; Russell et al. 2020 – Chapter 6). 62 Carnley Harbour during 1941–45 (de Lisle 1965). At least eight shipwrecks occurred at the Rainfall was moderate (1,500 mm per annum), and Auckland Islands during 1864–1907, and further spread over c. 310 days a year at Port Ross, with sheep and goats (Capra hircus) were liberated a slight autumn maximum. Orographic effects during this period in an attempt to provide a food created higher rainfall at Carnley Harbour (2,100 resource for shipwreck survivors (Egerton et al. mm per annum), spread over c. 330 days a year. 2009). Three attempts at pastoral farming between Mean daily temperatures were c.