7. the Birds of Rennell Island
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7. THE BIRDS OF RENNELL ISLAND BY DIANA BRADLEY a n d TORBEN WOLFF BRITISH MUSEUM (NAT. HIST.), LONDON ZOOLOGICAL MUSEUM, COPENHAGEN CONTENTS Introduction............................................................................. 85 Birds of Rennell Island .................................................... 87 Number and relationship of the Rennetl birds.. .. 115 Birds of Bellona Island .................................................... 117 Summary ............................................................................... 119 References............................................................................... 119 INTRODUCTION The present paper is partly a compilation of previously published records on the bird fauna of Rennell (and Bellona) Islands, and partly the results of the two recent Expeditions to Rennell. The first collector on Rennell Island was C. M. Woodford, who went there in 1906 and brought back with him, among other things, a bird which was described by N o rth as a new genus and species of the Zosteropidae, Woodfordia supcrciUosa. In 1927 G. A. V. S tanley visited Rennell from 15 August to 10 October and collected nine species (eleven specimens) of birds which were kept in alcohol. They were iden tified by Kinghorn ten years later (together with two specimens of a honey-eater also brought back by Woodford in 1906). We owe most of our present knowledge of the avifauna of Rennell to the Whitney South Sea Expedition which called there twice (27 August - 7 September 1928 and 17-29 May 1930) and collected 380 skins in all, representing 38 species. This fine collection was reported on by M ayr (1931). Finally, the Templeton Crocker Expedition visited Rennell several times in 1933 (6 June, 18-21 June, and 21 July). It secured 24 skins, representing nine species, which were listed by D avidson (1934). In 1951 T o rben W olff, a member of the Galathea Deep Sea Expedition, visited the island with the Danish Rennell Expedition from 12 October to 14 November. He collected in the Kanggava Bay area and the central part of the island and made one visit to Lake Te-Nggano. The collecting localities are listed by W olff (1955 b) and information about the nature of Rennell as well as a map of the island is given in the general Introduction (W olff 1955 a). In 1953 Diajs’a B rad ley visited Rennell liand with her husband to obtaip spec imens for the British Museum (Natural History). They collected on the eastern par^ of the island from 15 October to 28 November. A list of localities is given by J. D. B rad ley (1955). Immediately prior to Mr. and Mrs. B ra d ley ’s visit Dr. M arshall Laird and his wife made a short stay on Rennell and Bellona (Laird & Laird 1956). Altogether twelve specimens (representing seven species) were collected and blood smears taken as part of a survey of avian haematozoa in the Pacific. Dr. Laird has kindly allowed us to include data and measurements of the birds in the present report (marked “M. L.”). The collection is now in the Dominion Museum, Wellington, where Dr. R. F a lla was good enough to take the measurements given below. We wish to express our thanks to both. In this paper information (field notes, etc.) obtained by W o lff is marked “(TW)” , that obtained by Diana Bradley “(DB)”. All specimens collected by W o lff and now in the Copenhagen Museum are marked “C.M.” and those collected by Diana B rad ley and now in the British Museum are marked “B.M .” . Specimens were cither made into study skins or preserved in spirit. The latter are indicated in the text by the letter “S” preceding the collector’s number, which is in brackets. Some specimens were not kept, but were measured; they are indicated by the letters “NK”. Measure ments of specimens in spirit were taken while the birds were still fresh. The others were made on dried skins. Bills were measured from the feathers at the base of the culmen following the method used by M ayr (1931). All measurements are in millimetres. W o lff shot all the birds collected by the Danish Expedition. For various reasons his stay at the Lake in the interior had to be cut down to two days, which meant a comparatively low proportion of lake-dwelling birds in his collection. Specimens collected by Diana Bradley were brought to her by the natives, who killed them with catapults or caught them in snares, their usual method of catching birds for food. Nests were sometimes brought to her with any contents they had, and some times she was shown the nests in situ. She was largely dependent on native inform ation about the ownership of nests, except in the case of Plilinopus richardsii and Myzomela cardinalis, which had identifiable nestlings. Native information seemed to be reliable, for there was rarely any disagreement when several were questioned inde pendently. As Dr. F. W. B raestrup of the Copenhagen Museum is to treat the zoogeogra phy of the entire vertebrate land-fauna of Rennell Island as a whole, we have re frained from elaborating on the general conclusions to be drawn from the present material. His paper will be published as No. 9 of “1 he Natural History of Rennell Island” (Braestrup 1956). The native names of the birds are included in the text. About half of them were recorded by both authors, most of the others by Mrs. B rad ley. For details about the names and the role played by the birds as a source of food for the natives, see W o lff (1955 c). The English names are according to M ayr (1945 a), and the species are considered in the same order. Some of the colours of the specimms collected by W olff (especially of bills, legs, •etc.) were described by means of a colour index, viz. E. S eguy : Code universel des couleurs, Paris 1936. We wish to express our thanks to Dr. F in n Salom o nsen (Copenhagen) and Mr. J. D. M a c d o n a l d (London) for assistance during the preparation of the report. BIRDS OF RENNELL ISLAND 1. Podiceps novaehollandiae rennellianus Mayr Manusingi; Australian Dabchick. Colymbus ruficollis longiroslris (nec. Bo n n a t e r r e , 1790) M a y r, 1931, Amer. Mus. Novit., 486, p. 3; Rennell Island. Podiceps novaehollandiae rennellianus M a y r , 1943, Emu, 43, p. 6; (nom. nov.). S p e cim en s. Wing Bill Tarsus (135)5 ad. 18 Nov. 1953. Lake Te-Nreano 107 21 38 B.M. 009) 2 ad. 8 Nov. 1953 - - _ 100 21 37 B.M. (154) ? ad. 24 Nov. 1953 - - - (Moult) 21 35 B.M. Colour of bill, black: skin at base of bill, lemon-yellow; legs, black; iris, yellow. Field notes. A clutch of two plain white eggs was examined on 29 October; dimensions; 38 ■ 25, 37 v 25 (DB). T axonom ic notes. When compared with specimens in the British Museum col lections these specimens do not show very distinctly the characteristics of the race rennellianus. described by M a y r . D istribution. Rennell Island. 2. Pelecanus conspicillatus Temminck Kosi; Australian Pelican. Pelecanus conspicillatus T e m m in c k , 1824, Planch. Col. d'ois., livr. 47, pi. 276; New South Wales. L a ir d (1954) saw this species in the New Hebrides and reported it from Rennell (native information). About twenty had arrived early in 1952, and at the time of his visit, some eighteen months later, only two were known to be still living on the shores of the lake. The rest had been hunted for food. According to L a ir d pelicans “were quite new to the Rennellese”. They were probably carried to the New Hebrides and the Solomons (cf. C a in & G albraith 1956) from Queensland and New Guinea during a gale between 3 and 7 March 1952, blowing at altitudes between 1000 and 2300 metres (cf. M adsen (1930) who gives an explanation for the reason why large birds (such as pelicans, kites, vultures, crows, storks, etc.) are often observed at alti tudes of more than 1000 m in hot, tropical areas). No birds were seen at the time of my visit but the natives told me that pelicans have occurred before, which differs from the information given to L air d (DB). D istribution. Australia and South New Guinea; occasionally in the Solomons and the New Hebrides. , 3. Sula sola n ib ri^ Gould , Kanapu;‘ Red-footed Booby. , < Sula rubripes G o u l d , 1838, Synops. Birds Austr., pt. 4, App., p. 7; Raine Island, Queensland. S p ecim en . Wing Tail Bill (137) ? imm. 20 Nov. 1953. Lake Te-Nggano 393 218 84 B.M. Colour of bill, purplish-pink, darker at tip; legs, light salmon-pink; iris, outer ring, grey, inner, mauve. Field notes. During a voyage on 22 October from Lavanggu to Te-Uhungango on the South coast of Rennell several boobies and many terns were observed on a reef just east of the southern entrance to Kanggava Bay. Due to the heavy swell it was impossible to make closer observations or to determine their specific identity (TW). T axonom ic notes. The present specimen matches a large series of immature birds in the British and Copenhagen Museums. The mottled upperparts, white throat and upper breast distinguish it from the other two species of Sula occurring in the S. W. Pacific. The only race of S. sula recorded from there is S. s. rubripes Gould. D istribution. Indian, tropical western and central Pacific Oceans. 4. Sula leucogaster plotus (Forster) Kanapu;^ Brown Booby. ' Pelecanus plotus F o rster, 1844, Descr. Anim., ed. Licht., p.