[<ecords o{ the rVcstCrJJ Australian Museum 23: 115~ n2 (2006).

The birds of Gag Island, Western Papuan islands, Indonesia

R.E. Johnstone

Western Australian Museum, Locked Bag 49, Welsh pool DC Western Australia 6'1S6

Abstract This report is based mainly on data gathered during a biologicalsurvey of C;ag Island by a joint Western Australian Museum, MuseumZoologicum Bogoriense and Herbarium Bogoriense expedition in July 1'197. Atotal of 70 species of bird have been recorded for Gag Island and a number ofthese represent new island and/or Raja Ampat Archipelago records. Relativeabundance, status, local distribution and habitat preferences found for eachspecies arc described, extralimital range is outlined and notes on taxonomvare also given. No endemic birds were recorded for Gag Island but a numberof species show significant morphological variation from other island formsand may prove to be distinct taxonomically.

INTRODUCTION

Gag Island (0025'S, 129U 53'E) is one of the WesternPapuan or Raja Ampat Islands, lying just off theVogelkop of Irian Jaya, between New Guinea andHalmahera, Indonesia. These islands include (fromnorth to south) Sayang, Kawe, Waigeo, Gebe, Gag,Gam, Batanta, Salawati, Kofiau, Misool and anumber of small islands (Figure 1). Gag Island isseparated from its nearest neighbours Gebe Islandto the north~west, and Batangpele Island to thenorth-east, by about 40 km of relatively deep sea.Gag Island is roughly oval shaped 12 km long by 7km wide with its longest axis directed N-S and witha surface area of 56 km 2 (Figure 1). The east coast isdeeply indented by the shallow Gambir Bay, whichpenetrates about 1.5 km inland. Most of the coast isrocky but there are a number of sandy beaches onthe northern and western sides. Gag Island consistsmostly of undulating hills, the highest peakGunung Susu rising to 3]] m. The island contains anumber of small rivers and creeks including theMusawalo River in north and the Wapob River ineast draining into Gambir Bay. Sago swamps andfresh water springs are abundant including a fairlylarge spring fed lagoon in the south-west corner.There is a small village on the north side of GambirBav and a number of residents at Kampung Tua onthe northern coast. Domestic goats and domesticfowl occur throughout the cultivated areas and donot appear to have greatly disturbed the vegetation.

Gag Island was visited bv the joint WesternAustralian Museull1, Museum ZoologicumBogoriense and Ilerbarium Bogoriense groupbetween 9 and 20 Julv 1997. The major aim ofthe preliminary bird survey was to document theavifauna of the island and provide data on localdistribution, status and habitat preferences. Asmall collection was also made of species that

undergo geographic variation for taxonon,ic,morphological and genetic studies. Theannotated checklist provided covers everyspecies recorded, both historically and duringthis survey.

In the annotated list I summarise for each speciesits relative abundance (whether it is very common,common, moderately common, uncommon, scarceor rare), whether it feeds alone or in groups, status(a judgement on whether it is a vagrant, visitor orresident), habitat preferences and breeding season.Extralimital range is also briefly outlined and forthose species that are recognised as undergoinggeographical variation, taxonomic notes have beenprovided.

HabitatsEleven major habitat types were recognised on

Gag Island.I. Marine. Includes coastal seas, stacks, reef flats

and sandy and rockv shores.. .

2. Kebun. Cultivated areas, mainly coconutplantations but also banana, taro, breadfruitand mango etc (Figure 2).

3. Disturbed \'olcanic forest. Mostlv secondaryforest backing kebun in northern part of island(Figure] ).

4. Primal'\' volcanic forest. Lowland rainforestcovering most of the northern third of theisland. Tall luxuriant forest with a variablecanopy, 30~35 m with enwrgents to 45 m.Dominant genera include Diospyros sp.,Sterulia longitolia, Planchonella sp., Celtisphilippensis, Tricalysia malaccensis, Canariumlittorale and Champereia manillana (Figure 5).

J. Sago vegetation. Fairly extensive stands aroundCambir Bay and along Wapob River.

6. Grassland. Includes airstrip, open grassv areas

116 R.E. Johnstone

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Figure 1 Map of Gag Island showing main features.

around settlements and grassy hills On thesouth-east corner of island. (Figures I, 3 and 6).

7. Mangroves. Small stand of mangroves occursat mouth of a creek at Camp Two (south-eastside of island). Genera include Sonneratia,Ll1mnitzera, Ceriops, Brugl1iera, Xylocarpl1s,Rhizophora and Exoecaria.

8. Beach vegetation. Ranging from dense closedforest to open disturbed or partly cultivatedareas. Dominant plants include Barringtonia,Calophylll1m, Casl1arina, Scaevola, Pandanl1s,Tournefortia, Trema, Flagellaria, Hibiscus andTerminalia (Figure 7).

Birds of Gag Island

Figure 2 Gambir Bay, with BHP Camp on right and village backed by kebun on left.

Figure 3 Airstrip with rank herbage and kebun.

117

118 R.E. Johnstone

9. Ultra basic valley forest. Tall rainforestoccurring in valleys of southern two-thirds ofthe island. Dominant trees include Dillenia,HorsEieldia, Buchanania, Eugenia andClerodendrum (Figure 4).

10. Ultrabasic slope forest. Ranging from denseforest to open forest and scrub and occurringthroughout the southern two-thirds of theisland. Dominated by Gamau Ploiarium sessile,Calophyllum, Symplocos and Clerodendrumsp.

11. Ultrabasic ridge scrub. Ranging from areas ofopen shrubland and woodland to densethickets. Occurring throughout the southerntwo-thirds of the island. Dominated by shortand sparsely distributed Gamau Ploiariumsessile, Calophyllum articulatum, Planchonellaoxyedra and Clerodendrum sp.

ClimateGag Island has a tropical monsoon type climate,

characterised by year-round moderate temperaturesand high relative humidity. Its climate is influencedby the south-east trade winds from May to Octoberand the north-west monsoons from December toApril. The wet season (north-west monsoon) beginsin October, peaks in December-January and maycontinue until April. Mean daily temperatures varybetween about 21 0 and 340 C.

Figure 4 Rainforest near pit 8.

Figure 5 Disturbed volcanic forest along track to Turtle Beach.

Birds of Gag Island 119

Figure 6 Grassland of Alang alang south of Camp 2.

Figure 7 Lagoon, south-west corner of island.

Ornithological HistoryThe ornithological history of Gag Island is

rather sparse. The famous naturalist explorer A.R.Wallace spent several days on the island andcollected a small number of specimens on GagIsland (Gagie) in early 1860s; Or H.A. Bernsteinalso made a small collection on the island in 1863and 1864; Or J. Diamond and D. Bishop visitedthe island for a day in 1986. Apart from theirrecords several species are listed for Gag Island

by Peters (1967) and Sibley and Monroe (1990) intheir world distributional lists but their source ishowever unknown; la ter F. Crome (1997)compiled a list of 39 species for Gag Island (basedon literature records). As visits to Gag Island hadbeen of short duration and very infrequent itsavifauna was poorly known. This survey did notrecord eight of the birds previously listed for theisland, but added a further 24 species (see Table1).

120

ANNOTATED SPECIES LIST

Classification and nomenclature follows Andrew(1992) and White and Bruce (1986) and Johnstone(2001).

Fregatidae

Fregata minor Great Frigatebird

Eight birds off Turtle Bay on 11 July, also listedfor Gag Island in 1860s.

Extralimital range. Widespread in Indian andPacific Oceans, also south Atlantic Ocean.Moderately common around Ambon and aroundKai and Tanimbar Islands. (R.E. Johnstoneunpublished data).

Fregata ariel Lesser Frigatebird

Four following coast north-west corner of islandon 11 July and 10 over southern tip of island on 20July. These are the first records for Gag Island.

Extralimital range. Breeding on tropical islands inAtlantic, Indian and Pacific Oceans. Widespreadand moderately common in western Papuan region.

Sulidae

Sula sula Red-footed Booby

A beach washed skeleton found on north-east sideof island in July. A wide ranging species occurringthroughout tropical seas.

Ardeidae

Egretta alba Great Egret

One feeding on airstrip with two IntermediateEgrets on 14 July. Probably a scarce winter visitorfrom Australia or New Guinea, recorded patchilyin Wallacea, with no evidence of breeding.

Extralimital range. Much of Old World fromEurope and Africa east to Japan, Philippines,Solomons and New Zealand.

Egretta intermedia Intermediate Egret (Lesser Egret)

Moderately common. Single birds and groups (upto four). Mainly feeding on airstrip, edges of sagoswamps, open pools, grassy areas around camp andoccasionally seashore at creek mouths. Probablywinter visitors from Australia. The first records forGag Island.

Extralimital range. Africa south of Sahara andfrom Pakistan east to Japan, Philippines, Solomonsand Australia. Widely distributed in Wallacea andNew Guinea but little or no evidence of breedingand presumably most originating from Australia.

Ardea sacra sacra Eastern Reef Heron

Moderately common in ones, twos or threes.Resident. Mainly reef fIats, rocky shores, beachesand tidal flats. Both white phase and dark phasebirds recorded.

R.E. Johnstone

Extralimital range. Shores of east Indian Oceanand west and central Pacific. Widely distributed inthe region including remote atolls.

An/ea ibis coromanda Cattle Egret

Historical records. Previously listed for GagIsland but not recorded during the July survey.Also recorded from northern Moluccas andWestern Papuan, Waigeo and Yamna Islands.

Extralimital range. From southern and easternAsia south-east to northern and eastern Australiaand New Zealand. Only recently extended its rangeto include New Guinea. Records from northernMoluccas and Western Papuan islands. In easternWallacea dated specimens fall between September­November.

Accipitridae

Pandion haliaehls cristatus Osprey

Moderately common. Ones and twos recordedover northern end of island, at Gambir Bay, atCamp Two and over lagoon at south-west corner ofisland. Previously listed for Gag Island and residentjudging from a recently used nest in tree nearairstrip.

Extralimital range. This subspecies ranges fromPhilippines and Sumatra south-east to Australia andNew Caledonia. Widely distributed in coastal areasaround New Guinea.

Taxonomy. The subspecies melvillensis issometimes recognised for the birds from Indonesia,the Philippines, northern Australia and NewCaledonia and cristatus for southern Australia andTasmania. The smaller size of melvillensis ishowever doubtful judging from the wingmeasurements showing considerable overlap inWhite and Bruce (1986).

A viceda subcristata Pacific Baza

Status uncertain. Previously listed for Gag Islandbut not recorded in July.

Extralimital range. New Guinea region, BismarckArchipelago. Solomon Islands and northernAustralia. An Australasian species extending intoWallacea with some marked geographical variation;in Moluccas subspecies A. s. reinwardtii fromSeram, Ambon and Haraku and in western NewGuinea A. s. s ten02ona.

Haliastur indus girrenera Brahminy Kite

Moderately common, usually in ones,occasionally twos. Coasts especially sheltered bays.

Extralimital range. Northern Australia, Moluccas,New Guinea and Bismarcks.

Taxonomy. Two forms recognised in Wallaceanamely H. i. intermedius (Sulawesi and LesserSundas) and H. i. girrenera (Moluccas, and alsoeastern end of range).

Birds of Gag Island

Haliaeehls leucogaster White-bellied Sea-Eagle

Moderately common in ones and twos. Tworegularly seen over north end of island and GambirBay in July. Recorded over coasts and forest areas.

Extralimital range. India, Sri Lanka east toBismarcks and Australia.

Accipiter novaehol1andiae Grey Goshawk (VariableGoshawk)

Scarce or uncommon. One over open kebun on 13July and one over camp on 18 July also previouslylisted for Gag Island but status on the islanduncertain.

Extralimital range. Widely distributed in NewGuinea, Melanesia and Australia with many localisland forms. Eight subspecies recognised forWallacea including A. n. griseogularis from GebeIsland and nine in ew Guinea region.

Aquila gurneyi Gurney's Eagle

Probably a rare visitor from ew Guinea. Oneobserved twice over secondary forest on north endof island. Appeared to be attracted to roost of flyingfoxes (Pteropus). First record for Gag Island.

Extralimital range. ew Guinea extending westto Moluccas. In Western Papuan islands recordedfrom Misool and Waigeo.

Falconidae

Falco moluccensis Spotted Kestrel

Uncommon. Ones and twos in July also historicalrecords. Mainly open country on and aroundairstrip; also over cultivated areas and settlements.Easternmost records for Indonesia.

Extralimital range. Western Indonesia (Java,Moluccas, Sulawesi, Lesser Sundas).

Taxonomy. Two subspecies recognised F. m.moluccensis (Moluccas) and F. m. microbalia(Sulawesi region and Lesser Sundas). Birds fromGag Island appear most like the darker moluccensispopulations.

Anatidae

Tadorna radjah radjah White-headed Shelduck

Uncommon. Two over beach near creek mouthnorth-ea t side of island on 17 July. First record forGag I land.

ExtraJimital range. Moluccas, ew Guinea regionand northern Australia. Widely distributed butlocal on Western Papuan islands including Gebe.

Megapodiidae

Megapodius freycinet freycinet Dusky Scrubfowl

Common to very common. Mainly ones and twosoccasionally small groups (up to five). Mostnumerous in beach vegetation especially on northend of island; also disturbed volcanic forest;

121

Figure 8 Dusky Scrubfowl MegapodiL15 f freycinet.

primary volcanic forest; sago swamps, edge ofmangroves and once in dense Pandanus. umerousactive mounds in beach vegetation north end ofisland in July.

ExtraJimital range. orthern Moluccas, WesternPapuan Islands (Waigeo, Batanta, Kofiau, MisooJ,Gebe, Gag) also Geelvink Bay Islands.

Taxonomy. The Gag Island population (alongwith Gebe, Waigeo, Kofiau and Misool) was placedin the nominate subspecies M. f freycinet by Joneset a1. (1995).

Rallidae

Ral1ina tricolor Red-necked Rail

Scarce of rare. Status uncertain possibly a migrantfrom New Guinea. One calling and anothercollected from sago swamp on north end of island.First record for Gag Island.

Extralimital range. Moluccas, Lesser Sundas, ewGuinea region, Bismarck Archipelago and north­east Queensland. Recorded from Western Papuanislands (Misool and Waigeo).

Scolopacidae

umenius phaeopus variegatus Whimbrel

Scarce visitor. One on rocks south end of islandon 20 July. First record for Gag Island. Wintervisitor and passage migrant.

ExtraJimital range. Breeding in north-east Siberia,and wintering from east India, Taiwan and Palausouth to Australia and ew Zealand. Common andwidespread in Wallacea and ew Guinea regionmainly from August to April.

Tringa hypoleucos Common Sandpiper

Scarce visitor. Previously listed for Gag Island. InJuly single birds on rocks and edge of water onnorth end of island. A winter visitor and passagemigrant.

122

Extralimital range. Breeding in Europe and northand central Asia, and wintering in south Europe,Africa, south Asia and from Japan south toAustralia. A common passage migrant to Wallaceaand New Guinea.

Arenaria interpres interpres Ruddy Turnstone

Scarce or casual winter visitor and passagemigrant. Two on reef flat north end of island inJuly. First record for Gag Island.

Extralimital range. Breeding in far north of NorthAmerica, Europe and Asia and wintering fromJapan, Hawaii and California south to South Africa,Australia, New Zealand and South America.Widely distributed in Moluccas and New Guinearegion from March to November.

Burhinidae

Esacus magnirostris Beach Stone-curlew

Uncommon. Single birds observed on beachesand reef flats in July. First record for Gag Island.

Extralimital range. Coastal South-East Asia, NewGuinea region to Solomon Islands, northernAustralia and New Caledonia.

Laridae

Sterna hirundo longipennis Common Tern

Scarce visitor and passage migrant. Two on stackand later flying north off north-east side of islandon 11 July. First record for Gag Island. Thissubspecies breeds in north-east Asia and wintersfrom east India and Sri Lanka east to New Britain,Solomons and Australia.

Sterna sumatrana BIack-naped Tern

Moderately common in July in ones, twos andsmall groups (up to six). Beaches, reef flats andcoastal waters. First records for Gag Island.

Extralimital range. Breeding on islands in tropicalIndian and western Pacific Oceans fromMadagascar east to south China, Indonesia, NewGuinea, northern Australia and Samoa. Widespreadin Wallacea and western New Guinea coastalwaters.

Sterna fuscata Sooty Tern

Single bird following the shoreline near CampTwo on 19 July 1997. First record for Gag Island.

Extralimital range. Breeding on tropical andsubtropical islands in Indian Ocean and west Pacificand dispersing widely. Reported in small numbersin Moluccas and western New Guinea seas.

Sterna albifrons sinensis Little Tern

Scarce visitor and passage migrant. Three onbeach and following shoreline near Turtle Bay on17 July. First record for Gag Island.

R.E. Johnstone

Extralimital range. This subspecies occurs aroundshores of Indian Ocean and west and central Pacific.Moderately common and resident on islets III

Wallacea and western New Guinea region.

Sterna bergh Crested Tern

Scarce. Single birds (probably this species on size)observed offshore near Camp Two in July. Firstrecord for Gag Island.

Extralimital range. Shores of Indian Ocean andwest and central Pacific. Moderately common andresident on islets in Wallacea and western NewGuinea region.

Anous stolidus Common Noddy

One edge of water on sandy beach near airstripon 15 July. First record for Gag Island.

Extralimital range. Breeding on islands in tropicaland subtropical Indian Ocean and west and centralPacific dispersing widely. Moderately common andresident in Moluccas and western New Guineawaters.

CoIumbidae

Ptilinopus rivoli rivoli White-bibbed Fruit Dove

Common throughout the island; in ones, twos andoccasionally in small groups (up to five) at isolatedfruiting trees. Mainly primary volcanic forestdisturbed volcanic forest, ultrabasic valley forestand beach vegetation; less frequently in kebunvegetation and ultrabasic slope and ridge scrub.Most often observed feeding in canopy. Attractedto fruiting Gamau Ploiarium sessile.

Extralimital range. Moluccas including KaiIslands, Western Papuan islands (including Gebe,Gag, Misool) and most coastal islands; Geelvink BayIslands; Eastern Papuan Islands and BismarckArchipelago.

Taxonomy. Single adult male specimen from GagIsland is smaller (weight 95 g vs two males fromKai Islands 118-120 g), paler on upperparts and hasa darker purple lower breast patch than specimensfrom Kai Islands and may represent a distinct islandform. Forms a superspecies with P. solomonensis.

Ptilinopus viridis pectoralis Claret-breasted Fruit­Dove

Status uncertain. Not recorded in July 1997 butlisted for Gag Island in historical data. Possibly verylocal or only a visitor to Gag Island.

Extralimital range. South Moluccas (Buru,Ambon, Saparua, Seram) Western Papuan islands(Kofiau, 'Gag', Gebe, Waigeo and Misool), lowlandsof New Guinea, also Solomon Islands (separatesubspecies P. v. lewish)

Ducula myristicivora myristicivora Spice ImperialPigeon

Common in ones, twos and small flocks (up to

Birds of Gag Island

Figure 9 Spice Imperial Pigeon DlIclIla myristicivora.

eight). Mainly primary volcanic forest, disturbedvolcanic forest, ultrabasic valley forest and tallbeach vegetation; less frequently in kebun andmangrove forest. Mostly seen feeding in the canopyon fruits and berries. Often observed perched onhigh bare branches or in powerful direct flightabove the forest. Voice a loud gutteral 'urwoow'.

A small island species confined to easternMoluccas, Western Papuan islands (including Gebe,Gag Island and Misool) also Geelvink Bay Islands.

Macropygia amboinensis Slender-billed Cuckoo­Dove (Brown Cuckoo-Dove)

Common to moderately common. Mainly in onesand twos occasionally small groups (up to four).Favours edges of forest habitats including primaryvolcanic forest, disturbed volcanic forest, ultrabasicvalley and slope forest, also ultrabasic ridge scruband beach vegetation. Attracted to fruitingPloiarium in ultrabasic valley and slope forest.Commonly heard calling 'woo up' calls in mostforest habitats. Display flights observed and a nestwith one egg found in July.

Extralimital range. Sulawesi, Moluccas, all NewGuinea islands and eastern Australia.

Taxonomy. Several well marked local subspeciesin Moluccas. Single female from Gag Island doesnot match description of M. a. amboinensis or M. a.albiceps and further specimens are needed toconfirm the subspecific status of the Gag Islandpopulation.

Chalcophaps indica Emerald Dove

Moderately common in ones and twos. Mostobservations in ultrabasic valley forest; primaryvolcanic forest and beach vegetation; less frequentlyin ultrabasic slope and ridge scrub and kebun.Favours forest edges and thickets, feeding on theground on fallen fruits and seeds. First record forGag Island.

Extralimital range. India to South-East Asia, ewGuinea, Melanesia and Australia.

123

Taxonomy. This species has two distinct forms. Innominate indica males have a white forehead andsupercilium and grey crown; C. i. longirostris islarger, has a vinous brown crown and front and nosupercilium. The grey-crowned nominate formranges from Kashmir through south and south-eastAsia and the Philippines to the Moluccas, someWestern Papuan islands (Gebe and Kofiau) andislands in Geelvink Bay (Numfor, Biak, Meos, andNum). The brown-headed form occurs in the LesserSunda Islands, eastern New Guinea, some TorresStrait islands and northern and eastern Australia.The two forms intergrade in the Lesser SundaIslands and birds from Gag Island although mostlike the nominate race are also intermediate in anumber of characters. Further work in the WesternPapuan islands would help clarify the taxonomicstatus of these forms.

Chalcophaps stephani stephani Stephan's Ground­Dove

Locally moderately common but generallyscarce. Mainly singly, occasionally in twos.Largely confined to beach vegetation anddisturbed volcanic forest and edges of primaryvolcanic forest on north end of island; once edgeof kebun. Mostly observed feeding on groundincluding two flushed regularly from freshlyexposed earth and litter on a megapode mound inbeach vegetation. First record for Gag Island andone of the few Moluccan islands where this speciesand C. indica are sympatric.

Extralimital range. Nominate subspecies C. s.stephani ranges from Kai Islands, New Guinearegion (Aru Islands, Western Papuan islands(Misool, Salawati, Batanta and Waigeo) also othersatellite islands including Admiralty and Bismarckand also Solomon Islands. Another subspecies C. s.wallacei in Sulawesi. Its present distributionsuggests that it may have once inhabited theMoluccas but has been eliminated throughcompetitive exclusion with C. indica which iscontinuing to expand its range. Further work in thisregion is needed to define the current distributionand status of these pigeons.

Caloenas nicobarica nicobarica icobar Pigeon

Scarce. Single birds observed near Camp Two inecotone between mangroves and valley forest on 17and 19 July. First record for Gag Island. Highlynomadic favouring small wooded islands and islets.

Extralimital range. Widely distributed on smallforested islands from the icobar Islands, north­east Indian Ocean through the Sunda Islands,Philippines and ew Guinea region to westernMicronesia and the Solomon Islands. Patchilydistributed in Moluccas and on some WesternPapuan islands (Pecan Islands, Kofiau, Salawati andWaigeo).

124

Psittacidae

Eos squamata squamata Violet-necked Lory(Moluccan Red Lory)

Common. Mainly in pairs and small flocks (up to10) occasionally larger flocks (up to 20). Attractedto flowering sago and coconut palms; alsoflowering and fruiting forest trees and shrubs.Mostly observed in primary volcanic forest,disturbed volcanic forest, kebun (including sagopalms) and ultrabasic valley forest; less frequentlyin slope and ridge scrub. Often seen feeding incanopy taking flowers and fruits. One of the mostconspicuous birds on the island.

Extralimital range. Northern Moluccas andWestern Papuan islands (Batanta, Waigeo, Misool,Gebe and Gag).

Taxonomy. Four subspecies recognised namely:Eos squamata atrocaerulea (Moluccas); Eossquamata rinciniata (Moluccas); Eos squamataobiensis (Obi Island); and Eos squamata squamata(Western Papuan islands). Gebe Island is the typelocality for the nominate subspecies where birdshave the best developed collars. There are howeverslight differences between birds from Gebe Islandand those from Waigeo and Misool Islandsincluding a reduction in collar size. Judging fromobservations birds on Gag Island varied fromhaving a distinct collar to little or no collar and mayprove to be intermediate between Gebe and Waigeopopulations.

Micropsitta keiensis Yellow-capped Pygmy Parrot

Scarce or uncommon. Only observed on northend of island. Two groups of three in and overdisturbed volcanic forest on 17 July and two indense beach vegetation near airstrip on 18 July.Also historical records and possibly seen byDiamond in 1986. These birds are extremelydifficult to locate and may be more common thanrecords suggest. Calls include a high pitched insectlike' tseeet'.

Extralimital range. Kai Islands, Aru Islands,Western Papuan islands (including Gag Island andGebe) and western and southern New Guinea.

Cacatua galerita triton Sulphur-crested Cockatoo

Uncommon. In July only recorded in northernpart of island. Ones and twos in primary volcanicforest and disturbed volcanic forest, also oneobserved flying over camp in Gambir Bay.Previously recorded for both Gag Island and GebeIslands. Conspicuous and noisy and often seenperched on dead branches high up in canopy. Pairat nest hollow in huge tree in dense forest aboveWapob River in July.

Extralimital range. Moluccas, New Guinea regionincluding Am and Western Papuan islands andAustralia.

R.E. Johnstone

Electus roratus polychloros Eclectus Parrot

Common. Singly and in pairs. Largely confined toforest habitats i.e., primary volcanic forest,disturbed volcanic forest, ultrabasic valley forest,dense beach vegetation and less frequently in kebunand ultrabasic slope forest. Very conspicuous andnoisy, often observed flying high above the forestor perched high on dead branches. Several femalesflushed and returned quickly to hollows in forestnorth end of island in July.

Extralimital range. Moluccas, Lesser Sundas andNew Guinea region to Solomon Islands and north­east Australia.

Taxonomy. Three subspecies occur in the regionnamelv: Eclectus roratus riedeli from TanimbarIsland: E. r. polychloros (type locality Gebe Island)restricted to Seram Laut, Tayandu and Kai Islandsand some Western Papuan islands, and E. r.pectoralis on New Guinea mainland.

Geoffroyus geoffroyi pucherani Red-cheeked Parrot

Common. In ones, twos and small groups (up tofive). Mainly forest habitats; primary volcanicforest, disturbed volcanic forest, ultrabasic valleyforest, dense beach vegetation and less frequentlykebun and sago swamps.

Extralimital range. Lesser Sundas, Moluccas, NewGuinea region and north-east Australia.

Taxonomy. Marked geographic variation with 19subspecies recognised by Peters (1961). Thesubspecies G. g. pucherani occurs in WesternPapuan islands (Waigeo, Batanta, Salawati, Gebe,Gag Island and Misool) and north-western NewGuinea east to about Etna Bay.

Tanygnathus megalorynchos megalorynchos Great­billed Parrot

Uncommon. Usually in ones, occasionally twos,once three. Favours forested northern end of island.Primary volcanic forest, disturbed volcanic forest,ultrabasic volcanic forest and once in beachvegetation near airstrip. Also historical records forGag. Favours small forested islands.

Extralimital range. Moluccas, Lesser Sundas andWestern Papuan islands.

Taxonomy. Seven subspecies recognised.Nominate subspecies occurs on Talaut Islands,Sangir Islands, small islands off northern Sulawesi;northern Moluccas, Western Papuan islands(Waigeo, Batanta, Salawati, Gebe, Gag Island andMisool) and small islands off north-western NewGuinea.

CucuIidae

Cacomantis variolosllS Brush Cuckoo

Scarce or uncommon. Status uncertain possiblyresident or winter visitors from Australia. Ones andtwos in open beach vegetation near airstrip,

Birds of Gag Island

disturbed volcanic forest and kebun (cultivatedareas) in July. Two birds one a speckled immatureregularly calling from prominent perch near airstripin July. Also historical records for Gag Island andGebe Islands.

Extralimital range. Malaya and Sumatra east toBismarcks, Solomons and Australia.

Taxonomy. The nominate subspecies occurs in theregion as a winter migrant from Australia; thesubspecies C. v. infaustus is resident in southernMoluccas and western New Guinea region.

Chrysococcyx minutillus Little Bronze Cuckoo

One record. A single bird calling and flushedfrom sago swamp near camp on 13 July. The firstrecord for Gag Island.

Extralimital range. From Malaya and Sumatra eastto New Guinea and Australia.

Taxonomy. The Chrysococcyx 'malayanus' groupof bronze cuckoos (including minutillus, russatus,rufomerus and crassirostris) contains a number offorms sometimes regarded as separate species. Thedistribution and taxonomic status of this grouprequires further study.

Scythrops novaehollandiae Channel-billed Cuckoo

Uncommon. In ones and twos. Mainly forestednorthern parts of island. Recorded in primaryvolcanic forest, disturbed volcanic forest, ultrabasicvalley forest and kebun (cultivated areas). Onebeing attacked by two Torresian Crows (a majorhost species) on 14 July. Status in region uncertain;breeding resident and also a winter visitor fromAustralia.

Extralimital range. From Sulawesi and Flores eastto Bismarcks and northern and eastern Australia.

Taxonomy. The Sulawesi and Sula Islandspopulations are considered to represent an endemicsubspecies.

Caprimulgidae

Caprimulgus macrurus schlegelii Large-tailedNigh~ar

Locally moderately common but generallyuncommon. Resident. In ones and twos (probablypairs). Mainly observed in northern two-thirds ofisland (including proposed mine site). Recorded inultrabasic slope forest, ultrabasic ridge scrub, beachvegetation, kebun and sago vegetation and tracks inprimary volcanic forest. Flushed during day fromgrid line tracks and roads with little or no coverand also from small clearings in dense forest.Regularly heard calling at night. Also observedhawking for insects at night around Gambir Baycamp area. First records for Gag Island.

Extralimital range. India, South-East Asia, theGreater and Lesser Sundas, Philippines, Moluccas,New Guinea region and northern Australia.

125

Taxonomy. Populations from the Western Papuanislands (Waigeo, Salawati, Batanta) and those fromnorthern Moluccas are combined in the subspeciesC. m. schlegelii.

Apodidae

Collocalia esculenta Glossy Swiftlet

Scarce. Four circling cliffs near Turtle Bay andseveral old nests in small cave on coast near TurtleBay in July. First record for Gag Island.

Extralimital range. Bay of Bengal to south-westPacific.

Taxonomy. Considerable geographic variation inLesser Sundas, Moluccas and New Guinea region.Birds from Western Papuan islands are placed innominate subpecies C. esculenta esculenta.

Alcedinidae

Alcedo pusilla Little Kingfisher

Status uncertain. Not recorded during July surveybut collected on Gag Island by Bernstein in 1863.Possibly a scarce visitor to the island. Distributionand status in Moluccas and Western Papuan islandspoorly known.

Extralimital range. Moluccas south to northernAustralia and east to Solomon Islands.

Taxonomy. Populations in northern Moluccasoften separated from New Guinea birds as racehalmaherae. Taxonomic status of birds in WesternPapuan islands requires review.

Halcyonidae

Todiramphus sancta sancta Sacred Kingfisher

Common winter visitor and passage migrant fromAustralia. In July recorded throughout the island innearly all habitats Le., coasts, beach vegetation,kebun; disturbed volcanic forest; primary volcanicforest; sago vegetation; mangroves; beachvegetation; ultrabasic valley and slope forest; andultrabasic ridge scrub. Also collected by Wallace in1860s. In Moluccas the Sacred Kingfisher is aregular, common, winter visitor arriving in April­May-June and departing mid September to midOctober (Johnstone unpublished data). A fewindividuals may stay in their winter quarters.

Extralimital range. Breeding in Australia andpartly wintering in islands to north, from Borneoand Sumatra east to Bismarks and Solomons.

Todiramphus chloris chloris Collared Kingfisher

Uncommon. Single birds observed at Turtle Bay,also on coast at Kampung Tua on north end ofisland in July; also collected by Wallace andBernstein on Gag Island in early 1860s. Favoursvicinity of coast but much less frequent than BeachKingfisher.

Extralimital range. From Red Sea east through

126

south Asia, Philippines, Micronesia, New Guinearegion, northern Australia to Samoa and Tonga.

Taxonomy. Undergoes profound geographicvariation and has been divided into about fiftysubspecies. Birds from Western Papuan islandsbelong to nominate subspecies.

Todiramphus saurophaga Beach Kingfisher

Moderately common. Ones and twos. Coastalfavouring exposed reefs, rocky slopes, beaches,beach vegetation and coconut groves. Oftenobserved perched on dead branches, driftwood androcks at edge of seashore.

Extralimital range. Moluccas, New Guinea regionand North Melanesia. Largely a small islandspecies.

Taxonomy. Birds from Western Papuan islandsbelong to nominate subspecies.

Meropidae

Merops omatus Rainbow Bee-eater

Moderately common winter visitor and passagemigrant from Australia. In July mainly in smallparties (up to four) occasionally larger flocks (up to20). Recorded feeding over kebun areas (coconutplantations); disturbed volcanic forest; beachvegetation and over ultrabasic valley and slopeforest and camp area. First record for Gag Island. InAustralia moving northwards in February-May andsouthwards in October-November. Australian birdsranging north in winter to Lesser Sunda Islands,Moluccu region, Western Papuan islands and NewGuinea.

Coraciidae

Eurystomus orientalis pacificus Dollarbird

Common in July. Probably a resident and non­breeding migrant from Australia. In July recordedin ones, twos and small flocks (up to 25). Observedin open areas around airstrip; over coconutplantations; forest edges and perched in forestcanopy. One flock of 25 circling high over coconutplantation on 12 July. Also noted feeding on flyingtermites. The first records for Gag Island.

Taxonomy. The subspecies pacificus breeds innorthern and eastern Australia and winters onislands to north (from Sulawesi and Lombok east toNew Guinea). Other subspecies, including E. o.orientalis, from south and east Asia to Philippines,Bismarcks and Solomons.

Pittidae

Pitta sordida Hooded Pitta

Status uncertain. Not recorded in July 1997 surveybut listed for Gag Island by Diamond and Bishop(1986). Possibly very local on Gag Island or perhapsonly a casual visitor from nearby Gebe Island or

R.E. Johnstone

migrant from Asia. This species favours lowlandrainforest and mangroves and is generally silentand inconspicuous during dry season. A visitduring the 'wet' would no doubt confirm its statuson Gag.

Extralimital range. India, south-east Asia,Indonesia, New Guinea region including WesternPapuan islands and Bismarck Archipelago.

Taxonomy. Forms a superspecies with P. maxima(of Moluccas) and P. superba (of BismarckArchipelago).

Hirundinidae

Hirundo rustica Barn Swallow

Not recorded in July 1997, but listed in historicaldata. A non-breeding migrant from temperatenorthern hemisphere and likely to occur anywherein the region. The subspecies gutturalis of easternAsia and Japan winters in south-east Asia,Philippines, Sunda Islands, New Guinea region(including some Western Papuan islands) andnorthern Australia.

Hirundo tahitica Pacific Swallow

Moderately common (probably resident). Ones,twos and small groups (up to six) observed in July.Most frequent around habitation but also foragingover swamps and coastal areas. The first record forGag Island.

Extralimital range. India, South-East Asia, NewGuinea region, north-east Australia and Polynesia.

Hirundo nigricans Tree Martin

Moderately common. Most birds are probablywinter visitors from Australia. In ones, twos and smallflocks (up to eight) in July 1997. Mainly over opencultivated areas; coastal areas (including airstrip)and sago swamps. First record for Gag Island.

Extralimital range. Breeding in Australia (possiblyalso some breeding in Wallacea) and wintering inLesser Sundas, Moluccas and New Guinea region.

Taxonomy. Two subspecies recognised namely:H. n. nigricans (from Australia) and H. n.timoriensis (resident on Timor).

Campephagidae

Coracina papuensis papuensis White-belliedCuckoo-Shrike

Moderately common resident. Ones, twos andsmall groups (up to four). Mainly beach vegetation;cultivated areas (including coconut plantations andsago areas) and edges of forest (disturbed volcanicforest and ultrabasic valley forest). Also listed inhistorical data for both Gag Island and Gebe Islandsand Misool, Salawati and Batanta.

Extralimital range. Moluccas, northern Australia,New Guinea region, Bismarck Archipelago andSolomon Islands.

Birds of Gag Island

Taxonomy. The subspecies C. p. papuensis occursin the Moluccas and western and northern NewGuinea region.

Corvidae

Corvus orru Torresian Crow

Common resident. Mainly in twos and smallgroups (up to six). Beach vegetation; mangroves;cultivated areas (especially coconut plantations andsago swamps); also open areas and about habitation.Several old nests in tall trees near Turtle Bay. Alsohistorical records for Gag Island and Gebe Islands.Four specimens collected for taxonomic studies.

Extralimital range. Northern Moluccas, easternLesser Sundas, Australia, New Guinea region andBismarck Archipelago.

Taxonomy. Although Gebe Island birds have beenallocated to the nominate subspecies, the taxonomicstatus of several populations in Moluccas, NewGuinea and north-west Australia requires furtherstudy. There is considerable variation in calls andmorphology (including eye colour) and the species­subspecies limits need further appraisal.

Pachycephalidae

Pachycephala simplex Grey Whistler (also knownas Grey-headed Whistler P. griseiceps)

Common resident, in ones and twos. Mainlyforest habitats; primary volcanic forest; disturbedvolcanic forest; ultrabasic valley and slope forest;mangroves and dense beach vegetation; lessfrequently in cultivated areas (coconut plantationsand sago swamps). Mostly observed in mid-levelsand canopy of forest.

Extralimital range. Moluccas, New Guinea region(including Western Papuan islands, Misool,Salawati, Batanta Gebe, Gag Island and Waigeo)and northern Australia.

Taxonomy. The Grey Whistler P. simplex has beenrecently treated as conspecific with the Grey-headedWhistler (P. griseiceps). However there are somemorphological and vocal differences between the twoand this situation needs further appraisal. Populationsof simplex-griseiceps within the Moluccas andWestern Papuan islands also show considerablegeographic variation; some being yellow on theabdomen and with an olive back, others lacking theyellow and being brown backed. Specimens fromGag Island (P. griseiceps gagiensis) are stronglywashed with yellow on the underparts and are quitedifferent from the subspecies P. s. rufipennis of theKai Islands. Further study of the species-subspecieslimits within this group is required.

Myiagridae

Monarcha guttulus Spot-winged Monarch

Common resident. Usually in ones and twos.

127

Forest habitats: primary volcanic forest; disturbedvolcanic forest; ultrabasic valley and slope forest;dense beach vegetation and less frequently in kebunand sago swamps. Favours the middle and lowerlevels of the forest.

Extralimital range. Endemic to New Guinea, theAm Islands, Western Papuan islands (Misool,Salawati, Sagewin, Batanta, Wageo, Gag Island andGebe), islands in Geelvink Bay, D'EntrecasteauxArchipelago and Louisiade Archipelago.

Myiagra alecto chalybeocephala Shining Flycatcher

Uncommon to moderately common resident.Singly and in pairs. Mainly primary volcanic forest;disturbed volcanic forest; beach vegetation;mangroves; overgrown kebun (coconut plantation);sago swamps; and less frequently in ultrabasicvalley forest. Often in vicinity of water and foragesmainly in the understorey.

Extralimital range. Moluccas, New Guinearegion including Am and Western Papuan islands(Kofiau, Misool, Salawati, Batanta, Waigeo, Gebeand Gag). Also Bismarck Archipelago andnorthern Australia.

Taxonomy. Several subspecies recognised withinthe region namely M. a. alecto (northern Moluccas);M. a. longirostris (confined to TanimbarArchipelago); and M. a. chalybeocephala (WesternPapuan islands and most of New Guinea).

Muscicapidae

Muscicapa griseisticta Grey-streaked Flycatcher

Listed for Gag Island by Crome (1997).Breeds in south-eastern Siberia and winters in

southern Asia and east to the Moluccas and westernNew Guinea. Recorded from several WesternPapuan islands including Misool, Salawati, Batanta,Waigeo and Gebe.

Rhipiduridae

Rhipidura rufiventris gularis Northern Fantail

Moderately common resident. Usually in onesand twos. Mainly primary volcanic forest; disturbedvolcanic forest; ultrabasic valley and slope forest;kebun (coconut plantation); beach vegetation; andsago swamps. Conspicuous and often observedsallying for insects at forest edges.

Extralimital range. Moluccas, Western Papuanislands (Salawati, Batanta, Waigeo, Kofiau, Gag,Gebe and Misool), New Guinea, Bismarck andSolomon Islands; Lesser Sunda Islands andnorthern Australia.

Taxonomy. Shows considerable geographicvariation throughout the region especially in sizeand colour intensity; Le., in width and spotting ofthe breast band, extent of superciliary spot, colourof outer rectrices and edging of wing coverts. Birdsfrom Gag Island are similar in colouration to R. r.gularis of mainland New Guinea.

128

Rhipidura leucophrys Willie Wagtail

Moderately common resident. Usually in onesand twos. Most plentiful in cultivated areas(coconut and sago plantations) and aroundhabitation; also open or lightly wooded areas,beaches, edges of mangroves and around airstrip.One of the most conspicuous birds in the camp areaat Gambir Bay. Historical records for both GagIsland and Gebe Islands.

Extralimital range. Moluccas, Lesser Sundas, NewGuinea region, Solomon Islands and Australia.

Taxonomy. Birds from Gag Island match bestwith the subspecies melaleuca of New Guinea andthe Solomons.

Dicaeidae

Dicaeum 'pectorale' Papuan Flowerpecker (Olive­crowned Flowerpecker)

Status uncertain. Listed in historical records forGag Island and Gebe Islands (Crome 1997); anunidentified Dicaeum seen by Diamond in 1986;and a single Dicaeum making the typical 'Tsweet'call of Dicaeum hirundinaceum on edge ofrainforest on 10 July 1997.

Extralimital range. D. pectorale occurs throughoutNew Guinea and most satellite islands.

Nectariniidae

Nectarinia aspasia Black Sunbird

Very common resident. Usually singly sometimesin pairs. Occurs throughout the island butfavouring forests; primary volcanic forest; disturbedvolcanic forest; ultrabasic valley and slope forest;dense beach vegetation; mangroves; and sagoswamps; less frequently in ultrabasic ridge scruband dense plantations. Feeds both in lower levelsand canopy of forests. Not listed for Gag Island bymost previous workers but listed for the islandunder Cinnyris sericea by Peters (1967), see alsoMees (1965).

Extralimital range. Sulawesi, Moluccas, WesternPapuan islands (Misool, Kofiau, Salawati, Batanta,Waigeo, Gebe and Gag) also throughout NewGuinea and its satellite islands (Mees 1965).

Taxonomy. Gag Island birds belong to thenominate subspecies Nectarinia aspasia aspasiaranging throughout New Guinea and many satelliteislands (Mees 1965).

Nectarinia jugularis frenata Olive-backed Sunbird

Very common resident. Usually in ones and twos;occasionally small parties at flowering trees andshrubs. Recorded throughout the island butfavouring more open habitats than the BlackSunbird, Le. mostly cultivated areas (kebunincluding coconut plantations; sago swamps; openbeach vegetation and ultrabasic ridge scrub; alsoedge of forest habitats. Several pairs building nests,

R.E. Johnstone

suspended from exposed roots, under low cliffs inJuly.

Extralimital range. South-east Asia, Moluccas andSunda Islands, New Guinea region, north-easternAustralia and Solomons.

Taxonomy. Birds from Gag Island belong to thesubspecies N. j. frenata occurring on New Guineaand satellite islands (also other subspecies innorthern Moluccas and Australia).

Estrildidae

Lonchura molucca Black-faced Munia

Scarce. Two feeding on seeds from green grassheads on track in secondary forest near airstrip on15 July and two in grass edge of airstrip on 19 July.First record for Gag Island and the Western Papuanislands.

Extralimital range. Sulawesi, Moluccas, LesserSunda Islands and several small islands off Bali andnorth-east Java.

Sturnidae

Aplonis metallica Metallic Starling

Common resident. Mainly in small flocks (up to35), occasionally larger flocks (up to 50). Recordedin cultivated areas especially coconut plantations,gardens, disturbed volcanic forest, primary volcanicforest, sago vegetation, beach vegetation, ultrabasicforest and scrub areas and in mangroves. Noisy andgregarious. Observed feeding on flowering Albizia,fruits of Gamau Ploiarium sessile and flyingtermites.

Extralimital range. Moluccas, New Guinea regionincluding most satellite islands, Solomons andAustralia.

Taxonomy. Birds from Gag Island belong to thenominate subspecies A. m. metallica of Moluccas,New Guinea and north-eastern Australia.

Artamidae

Artamus leucorhynchus White-breastedWoodswallow

One over beach vegetation near airstrip on 20 July1997. First record for Gag Island.

Extralimital range. Ranging from India eastwardto New Guinea, Australia, New Caledonia and Fiji.

DISCUSSION

A total of 62 species (47 non-passerine and 15passerine) were recorded during this survey. Thisincludes 24 species not previously recorded for GagIsland and several that are important distributionalrecords for the region. Despite its small size (56km2) Gag Island has a relatively rich avifauna withthe most conspicuous feature the high proportionof pigeons and parrots. It also contains a number of

Birds of Gag Island

species that are restricted to small low islands and anumber of species that range widely throughout theOriental, Australian and New Guinea regions.

Few additional resident species could beexpected, however more work during differentseasons would no doubt add many visitors to thelist. Crome (1997) listed 38 species previouslyrecorded for Gag, and of these eight species werenot recorded during this survey namely: CattleEgret, Pacific Baza, Claret-breasted Fruit-Dove,Little Kingfisher, Hooded Pitta, Olive-crownedFlowerpecker, Barn Swallow and Grey-streakedFlycatcher. Of these the Barn Swallow and Grey­streaked Flycatcher are both visitors from thenorthern hemisphere and would not be expectedduring July. The Cattle Egret has only recentlyexpanded its range into the Western Papuan regionand has a very patchy distribution. The Pacific Baza,Claret-breasted Fruit-Dove, Little Kingfisher andHooded Pitta are often also very localised indistribution and may have been overlooked, or theymay be only occasional visitors to Gag. Thedisparities between species previously recorded forGag Island and the 1997 survey suggest that theland-bird fauna is in a state of flux with somespecies turnover. On the other hand it is difficult tojudge how complete and accurate the historicalrecords are for Gag. Some of the fruit-eating birds,especially the pigeons, are well known for theirability in colonising and moving between smallislands to take advantage of flowering and fruitingtrees.

Combining all records gives a total of 70 species.As with many islands in the Indonesian and NewGuinea region non-passerine species outnumberpasserines by a ratio of about 2:1 Gohnstone et al.1996). The ratio in continental Australia and NewGuinea is about 1:1. A breakdown of most of theGag Island avifauna is as follows.

1. Marine speciesFregata minorFregata arielSula sulaSterna hirundoSterna sumatranaSterna fuscataSterna albifronsSterna bergiiAnous stolidus

2. Non-breeding winter visitors from PalaearcticArenaria interpresl\:umenius phaeopusTringa hypoleucosHirundo rustica

3. Winter visitors from AustraliaEgretta albaEgretta intermedia

129

Halcyon sanctaMerops ornatusEurystomus orientalisHirundo nigricans

4. Visitors from New Guinea

Aquila gurneyiRallina tricolor

5. Resident species

Egretta sacraPandion haliaetusHaliaeetus leucogasterAccipiter novaehollandiaeFalco moluccensisTadorna radjahMegapodius freycinetEsacus magnirostrisMacropygia amboinensisChalcophaps indicaChalcophaps stephaniCaloenas nicobaricaPtilinopus rivoliDucula myristicivoraEos squamataCacatua galeritaMicropsitta keiensisGeoffroyus geoffroyiTanygnathus megalorynchosEclectus roratusCacomantis variolosusChrysococcyx minutillusScythrops novaehollandiaeCaprimulgus macrurusCollocalia esculentaTodiramphus chlorisTodiramphus saurophagaEurystomus orientalisHirundo tahiticaCoracina papuensisRhipidura rufiventrisRhipidura leucophrysMonarcha guttulusPachycephala simplexNectarinia jugularisLonchura moluccaAplonis metallicaCorvus orru

Gag Island is situated in the transition zonebetween the Austro-Papuan region to the east andthe Wallacean faunal region to the west. Most of theresident species recorded for Gag Island also occurin the adjacent New Guinea lowlands and on othernearby islands. Judging from the distributions andsubspecific affinities most of the birds have beenderived from New Guinea. A small elementincluding the Spotted Kestrel (Falco moluccensis)and Violet-necked Lory (Eos squamata) areWallacean in origin. The zoogeographical

130 R.E. Johnstone

Table 1 Species distribution in habitats during July 1997 survey

Species M KB DVF PVF SA GR MA BV UVF USF URS

Fregata minor xFregata ariel * xSula sula xEgretta alba xEgretta intermedia * x x xEgretta sacra xPandion haliaetus x xHaliastur indus x x xHaliaeetus leucogaster x x xAccipiter novaehollandiae xAquila gurneyi * xFalco moluccensis x xTadorna radjah * x xMegapodius freycinet x x x x xRallina tricolor *Esacus magnirostris * xArenaria interpres * xNumenius phaeopus * xTringa hypoleucos xSterna hirundo * xSterna sumatrana * xSterna fuscata * xSterna albifrons * xSterna bergii * xAnous stolidus * xMacropygia amboinensis x x x x x xChalcophaps indica * x x x x x xChalcophaps stephani * x x x xCaloenas nicobarica * x xPtilinopus rivoli x x x x x x xDucula myristicivora x x x x x xEos squamata x x x x x x xCacatua galerita x xMicropsitta keiensis x xGeoffroyus geoffroyi x x x x x xTanygnathus megalorynchos x x x xEclectus roratus x x x x x xCacomantis variolosus x x xChrysococcyx minutillus * xScythrops novaehollandiae x x x xCaprimulgus macrurus * x x x x x xCollocalia esculenta * xTodiramphus chloris x xTodiramphussancta x x x x x x x x x x

connections of Gag Island are largely with Waigeoand the western part of the Vogelkop.

Gag Island has no endemic species but contains anumber of birds that exhibit significant geographicvariation in the region including Grey Goshawk(Accipiter novaehollandiae), Dusky Scrubfowl(Megapodius freycinet), White-breasted Fruit Dove(Ptilinopus rivoli) , Slender-billed Cuckoo Dove(Macropygia amboinenesis), Emerald Dove(Chalcophaps indica), Violet-necked Lory (Eossquamata), Red-cheeked Parrot (Geoffroyusgeoffroyi), Little Bronze Cuckoo (Chrysococcyx

minutillus), Torresian Crow (Corvus orru), GreyWhistler (Pachycepahala simplex), ShiningFlycatcher (Myiagra alecto) and Northern Fantail(Rhipidura rufiventris). Specimens from Gag Islandof Ptilinopus rivon Macropygia amboinensis,Chalcophaps indica, Pachycephala simplex­griseiceps and Corvus orru differ fromneighbouring New Guinea and Moluccanpopulations and require further taxonomicassessment. Some of these may prove to be distinctisland forms and if so, their future conservation onGag Island will need to be addressed.

Birds of Gag Island

Table 1 (cont.)

Species M KB DVF PVF SA GR MA BV UVF USF

131

URS

Todiramphus saurophagaMerops ornatusEurystomus orientalisHirundo tahitica *Hirundo nigricans *Coracina papuensisRhipidura rufiventrisRhipidura leucophrysMonarcha guttulusMyiagra alectoPachycephala simplexDicaeum pectorale'Nectarinia aspasiaNectorinia jugularisLonchura molucca *Aplonis metallicaArtamus leucorhynchus *Corvus orru

x

x

x xx x xx x x xx x xx x xx x x x

x x xx x xx x x xx x x x x xx x x x x x

x x x x x xx x x

x xx x x x x x

xx x x x

x

xx

xxxxx

x

x

x

x

x

x

x

x

xx

x

Legend. M =Marine (coastal seas, stacks, reef flats and sandy and rocky shores); KB =Kebun (cultivated areas especiallycoconut plantations); DVF = Disturbed volcanic forest; PVF = Primary volcanic forest; SA = Sago swamps; GR =Grassland areas; MA = Mangroves; BV =Beach vegetation; UVF =Ultrabasic valley forest; USF = Ultrabasic slope forest;URS = Ultrabasic ridge scrub.

* New records for Gag Island.

A breakdown of the avifauna under each of the main habitat types is given below (where the status of a species issimilar in two or more habitats it was included in each of them)1. Beach vegetation: 32 species (12 passerine)2. Kebun: 29 species (11 passerine)3. Disturbed volcanic forest: 27 species (8 passerine)4. Marine: 23 species (1 passerine)5. Primary volcanic forest: 21 species (6 passerine)6. Sago: 19 species (11 passerine)7. Ultrabasic valley forest: 19 species (8 passerines)8. Ultrabasic slope forest: 13 species (5 passerines)9. Ultrabasic ridge scrub: 10 species (4 passerine)10. Mangroves: 9 species (5 passerine)11. Grassland: 4 species (1 passerine)

This gives an indication of the richness of each habitat type, but more particularly it shows the importance of thenorthern forest habitats and the ultrabasic valley forests.

Gag Island does support a number of species withhigh conservation importance (Collar et a1. 1994)including Dusky Scrubfowl, Nicobar Pigeon,Sulphur-crested Cockatoo, Yellow-capped PygmyParrot, Great-billed Parrot and Eclectus Parrot.Most of these have declined in numbers in otherparts of Indonesia due to capture for the wild birdmarket. Gag Island is also part of a region thatprovides important wintering grounds for manyAustralian landbirds including the SacredKingfisher, Rainbow Bee-eater and Tree Martin.

In order to minimise the impacts of mining onGag Island it should be a priority for baselinesurveys to identify and characterise the threatenedhabitats; establish and maintain sites for long term

studies; continue to map species ranges andascertain breeding bird densities in certain habitatsand monitor changes in populations. It is also quiteclear from this study that next to nothing is knownabout many of the other small islands in thisArchipelago. An expanded programme ofbiological surveys and studies in the region isurgently needed so that biological information canbe integrated into the region's development andconservation planning.

ACKNOWLEDGEMENTS

It is a pleasure to express thanks to WarwickAlliston and staff of BHP Gag Island for their help

132

and hospitality during the July survey. I alsogratefully acknowledge the support given by theWestern Australian Museum, Perth, the MuseumZoologicum Bogoriense, Bogor and NSREnvironmental Consultants Pty Ltd, Melbourne.

REFERENCES

Andrew, P. (1992). The Birds of Indonesia: a Checklist(Peters sequence). Indonesian Ornithological Society,Jakarta.

Beehler, B.M., Pratt, T.K., and Zimmerman, D.A. (1986).Birds of New Guinea. Princeton University Press,Princeton.

Crome, F. (1997). Ecological and biodiversity issues onGag Island - results of a desktop study. A Report toNSR Environmental Consultants.

Collar, N.J., Crosby, M.J. and Stattersfield, A.J. (1994).Birds to watch2: the World List of Threatened Birds.D.K. Birdlife International, Cambridge.

Gray, G.R (1862). Remarks on, and descriptions of, newspecies of birds lately sent by Mr A.R Wallace fromWaigiou, Mysol, and Gagie Islands. Proceedings ofthe Zoological Society of London 1861: 427-438.

Johnstone, R.E. (1994). Observations of Seabirds andShorebirds in Nusa Tenggara (Lesser Sundas) andMoluccas, Indonesia. Western Australian Naturalist19: 339-349.

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Johnstone, RE. and Sudaryanti (1995). The birds ofBanda Neira, Moluccas, Indonesia. WesternAustralian Naturalist 20: 15-19.

Johnstone, RE., Prawiradilaga, D. and Sudaryanti (1994).Distributional patterns of birds in Eastern Indonesia,particularly Australian-Indonesian seabirds,rainforest and mangal dwellers. Paper and abstractpresented to symposium on 'Terrestrial VertebrateBiodiversity in Indonesia'.

Johnstone, RE., Jepson, P., Butchart, S.H.M., Lowen, J.Cand Prawiradilaga, D. (1996). The birds of Sumbawa,Moyo and Sangeang Islands, Nusa Tenggara,Indonesia. Records of the Western AustralianMuseum 18: 157-178.

Johnstone, RE. (2001). Checklist of birds of WesternAustralia. Records of the Western AustralianMuseum Supplement No. 63: 75-90.

Jones, D.N., Dekker, RW.RJ. and Reselaar, CS. (1995).Birds families of the world The MegapodesMegapodiidae. Oxford University Press, Oxford.

Mees, G.F. (1965). A revision of Nectarinia sericea(Lesson). Ardea 53: 38-56.

Mees, G.F. (1972). Die V6gel der insel Gebe. ZoologischeMededelingen 46: 69-89.

Sibley, CG. and Monroe, B.L. (1990). Distribution andTaxonomy of Birds of the World. Yale UniversityPress, New Haven.

Manuscript received 29 July 1998; accepted 10 December 2005