New Behavioral, Ecological, and Biogeographic Data on the Avifauna of Rennell, Solomon Islands 1

Home , Anuta, Avian foraging, Guadalcanal, Mborokua, Ontong Java Atoll, Ranongga

CHRISTOPHER E. FILARDI,2 CATHERINE E. SMITH, 2 ANDREW W. KRATTER, 3 DAVID W. STEADMAN,3.5 AND H. PRICE WEBB4

ABSTRACT: During an expedition to Rennell, Solomon Islands, from 20 to 30 June 1997, we collected specimen and observational data that add to our under standing of this island's unique avifauna. We observed three species previously unrecorded on Rennell: a putative caprimulgid species, the Tree Martin (Hirun do nigricans), and the Black-faced Cuckoo-shrike (Coracina novaehollandiae), suggesting that further research will add to the known Rennell avifauna. In combination with previous work, our specimen data suggest that many Rennel lese land birds have prolonged breeding seasons typical ofthose ofbirds oflow land tropical regions. Our observations indicate that two species, the Great Cormorant (Phalacrocorax carbo) and the Singing Starling (Aplonis cantor oides), have colonized Rennell and increased in abundance over the past several decades. Reported initially as vagrants, the population establishment and in creases of these two species portend the importance of vagrant species on islands subjected to increased human disturbance.

RENNELL ISLAND LIES 168 km south of the nell's avifauna is depauperate, having about main chain of the Solomon Islands (Figure 50% of the species richness of a comparably 2 1). The avifauna of this large (676 km ) up sized island in the main chain of the Solo lifted coralline limestone island is indisput mons (Diamond and Mayr 1976). Systematic ably distinct. Of 37 breeding land and fresh affinities suggest that dispersal of species to water bird species, five species and nine Rennell may have occurred directly from subspecies are endemic, and six additional Vanuatu, New Caledonia, and Australia in subspecies are endemic to Rennell and addition to the main chain of the Solomons nearby Bellona (a smaller raised limestone (Diamond 1984). island 24 km northwest of Rennell). Ren- Rennell's birds are known largely from analysis of external characters from study skins plus observations duri~g infrequent re search expeditions. Initial scientific explora 1 Financial support came from the University of Flor tion by Stanley and Hogbin in 1927 was fol ida Division of Sponsored Research (to D.W.S.), lowed with two visits by the Whitney South National Science Foundation grant EAR-9714819 (to D.W.S.), the Ornithology Endowment at the University Seas Expedition in 1928 and 1930 (Mayr of Washington Burke Museum (to C.E.F., C.E.S.), the 1931, Mayr and Hamlin 1931), additional University of Washington Department of Zoology work by Bradley and Wolff (1956), and more (C.E.F., C.E.S.), an Eddy Fellowship (C.E.F.), and an recently Wolff (1973) and Diamond (1984). NSF Predoctoral Fellowship (C.E.S.). Manuscript ac Most expeditions to Rennell have occurred cepted 1 February 1999. 2 Burke Museum and Department of Zoology, Uni frorn August to November, with one trip in versity of Washington, Box 353010, Seattle, Washington May 1930, and four days in June-July 1933. 98195-3010. Unfortunately, specimens collected in the 3 Florida Museum of Natural History, University of 1920s through 1950s typically lack the exten Florida, P.O. Box 117800, Gainesville, Florida 32611. 42048 White Oak Circle, Kennesaw, Georgia 30144. sive data that give modern specimens so 5 Corresponding author (telephone, 352-392-6571; fax, much value, such as weight, soft part colors, 352-846-0287; E-mail, [email protected]). . molt, gonad size and condition (to determine 319 320 PACIFIC SCIENCE, Volume 53, October 1999

,~.:.;\ .r if X "" Ontong Java Atoll ~~.~:~~~~: :::'::-':'0, \'l}-i\\Ver,'a -..l~'bq:~., ...... \•.1 "' ro?;\O\'b ~Ia Lavella Arnavon Is. (same scale) 0 Mbava::-.w:~"IItJ°JOmbangara 6 S ~Dai iJR~~~fador ~ Ranongga5\'\} [i0. New Georgia vonavo~ Simbo# Sikaiana .; .. KOhingg;:J . . NEW GEORGIA RendOV~ nVan9UnU FLORIDA ~ 'V-o. ISLANDS ,.. ~ GROUP Telepare Nggalokae ~p ~~~\e i. ~~. ! G ~~~UYU Mborokua Sav8 ~Nggela ~ I RUSSELL Pile SOLOMON ISLANDS ISLANDS

o 100 200 300 ! I I I KM

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FIGURE 1. The Solomon Islands. breeding phenology), bursa and skull ossifi pare with those of Diamond and others, cation (to determine age of specimens), and higWight the most striking differences and stomach contents. In addition, tissue preser their significance, and comment on changes vation (for molecular analyses) was not a in Rennell's avifauna over the past half common practice until this decade, and only century. one previous expedition to Rennell (M. C. LeCroy and H. P. Webb in June 1995) pre Study Area and Methods served tissue samples. Because of these pro nounced gaps, the knowledge about Rennell On 20 June 1997, we flew from Gua Island birds was enhanced considerably by dalcanal to Hatagua Airstrip at Tinggoa Vil our specimen data and field observations lage, near the west end of Rennell (Figure 2), during 20-30 June 1997. arriving at 0830 hours. We spent 24 hr near The most recent and complete treatment the airstrip observing birds and passed the of the Rennellese avifauna is by Diamond night at Mendana Resthouse (MR) at the (1984), based on fieldwork during 5-13 Oc west end of the airstrip. On 21 June we de tober 1976. Although his observations are parted for Lake Te Nggano, the largest lake extensive, Diamond collected no specimens. in the South Pacific. The 8-hr tractor journey To avoid repetition, we provide only a cur included frequent stops, when we made ad sory treatment of topics covered more thor ditional observations. We arrived at the lake oughly by Diamond. Following the species several hours after dark. A 45-min canoe ride accounts, we address how our results com- took us to the Tahamatangi Resthouse (TR), New Data on the Avifauna of Rennell-FILARDI ET AL. 321

11° 40' S

RENNELL o...... 2 4 6 8 kilometers 0123456 miles

FIGURE 2. Rennell Island, showing localities mentioned in text. near Hutuna Village on the west shore of the last two days, when no substantial precipita lake. TR served as our base from 22 to 28 tion occurred. June. Most of our observations and specimen Much of the fruiting and flowering was collections were within a 2-km radius of TR confined to various epiphytes, understory (see locality specifics below). We made day plants, scattered trees (e.g., Ficus spp., Va trips to mature forest and Tuhungganggo vaea sp., Cocos nucifera), or early succes Beach on 24-26 June. On 28 June we de sional and edge species, such as Hibiscus ti parted TR, crossed the lake again, and re liaceus, Macaranga harveyana, and Pipturus turned by tractor to the airstrip. Again we argenteus. Most of the large canopy trees, stayed at MR, observing birds along the trail such as Canarium, Myristica, Callophyllum, west of the airstrip on the afternoon of 28 Homalium, and Terminalia, were not in fruit June and morning of 29 June. We departed or flower. for Guadalcanal at midday on 29 June. We set up three mist-net lines. Five nets Mornings at Lake Te Nggano generally were placed along a transect through sec began with hazy to partly cloudy skies and ondary forests of various ages, including two strong winds off the lake just south of east at nets in recently abandoned « 5 yr) garden ca. 25 km/hr. Daytime temperatures reached plots and three nets in denser, older (l0 ca. 28°C. Mternoons featured rain squalls off 20 yr) second growth. The canopy was less the lake that on several occasions coalesced than 10m tall in both habitats. Three nets into heavy rains late in the day. Winds were set up in more mature forest I km to maintained a heavy chop on the lake, which ward Hutuna from TR. These two lines op prevented canoe travel to the islets that har erated from 22 to 27 June. Three additional bor roosts of aquatic birds. The winds settled nets were set up from 25 to 26 June in tall, and skies became more overcast during our mature forest ca. 2 km from Tuhungganggo 322 PACIFIC SCIENCE, Volume 53, October 1999

Beach. Net captures were supplemented with morning of 21 June, late afternoon 28 June, collection of birds via hunting by Rennellese and morning of 29 June. We made observa Mart Taieha. The specimens (skins, skel tions from the airfield, the resthouse and vi etons) are housed at the Florida Museum of cinity, and along 1.5 km of road heading Natural History (UF), the University of west from the airstrip through active and Washington Burke Museum (UWBM), and abandoned gardens, secondary forests, and the Solomon Islands National Museum. edges of mature forests. Stomach contents from collected speci We did no standardized censusing of mens, preserved in isopropyl alcohol, are birds. Measures of relative abundance reflect housed at UFo Stomach contents were iden incidental encounter rates of a species and tified by A.W.K. using a light microscope. were assigned according to the following cri Heart, liver, and muscle tissue were taken teria: (1) rare, encountered once or twice at a from all specimens deposited at UWBM and locality pooling all observers over all days; most specimens deposited at UFo Tissues (2) uncommon, encountered daily or almost were minced under sterile conditions and put daily at a locality, pooling all observers over in kryo tubes with lysis buffer. Field ob all days (encounter rate variable); (3) com servations were tabulated daily. Species ac mon, encountered regularly by all observers counts based on cumulative notes and ob over all days at a locality; (4) abundant, servations by all authors were compiled unavoidable fixtures of a given habitat or immediately after leaving Rennell. Termi locality. nology for foraging observations follows Remsen and Robinson (1990). Tachybaptus novaehollandiae rennellianus. Australian Dabchick. Manusigi. This species occurs from Java east through New Guinea and Australia to the Solomon SPECIES ACCOUNTS Islands, Vanuatu, and New Caledonia; T n. Species designations primarily follow rennellianus is endemic to Lake Te Nggano Mayr (1945), but also incorporate some re on Rennell. visions by Bradley and Wolff (1956), Hadden LAKE: Common; confined to the lake; up (1981), and BeeWer et al. (1986). English and to three adults regularly just offshore from Rennellese names follow Diamond (1984). TR, usually in protected water; two adults Each account is divided into four separate and an immature seen together around an areas on Rennell where we made observa islet 80 m offshore; no direct foraging obser tions. We define these areas here and refer to vations, but individuals dived regularly in the them by name only in the species accounts. karst shallows along the lakeshore; no vocal LAKE: Tahamatangi Resthouse and vicin izations or courtship behavior observed. ity, west shore of Lake Te Nggano, 2 km FOREST AND COAST, ROAD, AIRSTRIP: Not NNW of Hutuna. Observations made be recorded. tween 22 and 28 June from resthouse garden, lakeshore, old gardens, young second-growth Sula leucogaster plotus. Brown Booby. Ren forest, and submature forest. nell name: see Diamond (1984). FOREST AND COAST: 4.2 km NW of Hu This pantropical species occurs widely in tuna. Observations on 24-26 June in mature the western Pacific. forest, along cliffs, and from Tuhungganggo Beach. LAKE: Uncommon; groups up to six, always far from shore over open lake. ROAD: Road from Tinggoa to western end of Lake Te Nggano. Observations on after FOREST AND COAST: Four flying 600 noons of 21 and 28 June. 700 m offshore beyond the edge of the fring ing reef. AIRSTRIP: Hatagua Airstrip at Tinggoa and vicinity. Observations all day 20 June, ROAD, AIRSTRIP: Not recorded. New Data on the Avifauna of Rennell-FILARDI ET AL. 323

Fregata minor minor. Great Frigatebird. Ka FOREST AND COAST, ROAD, AIRSTRIP: Not taha'ugi, kataha genga. recorded. This nearly pantropical species occurs Specimen Summary and Comments: One widely in the western Pacific. male and one female collected. Guts of both contained exclusively large (190-250 mm) LAKE: Common; suspected roost north of TR; up to 26 together; largest group flying Tilapia sp. fish. Female had five fish totaling 370 g, more than 18% of her body weight. low, north to south over TR with many birds No wing or tail molt in either bird. Gonads preening and "shake-drying" on the wing enlarged. Enlarged testes and ova plus after a late morning squall; overall ratio of absence of remex or rectrix molt suggest adult males to females and immatures ca. breeding at this time of year. Diamond 1: 5. (1984) first recorded P. c. novaehollandiae on FOREST AND COAST: Five kettling along Rennell in 1976, describing it as a probable the cliff edges above Tuhungganggo Beach; Australian vagrant. Gibbs (1996) stated that several groups of two to three beyond fring Rennell natives reported this cormorant as ing reef. already breeding on Rennell in 1994. Our data further confirm that this cormorant ROAD: Not recorded. breeds on Rennell and that its population has AIRSTRIP: Five over road west of airstrip increased since the 1970s. The transition on 28 June. from vagrant to resident breeder follows the introduction (in 1957) and subsequent ex Fregata ariel ariel. Lesser Frigatebird. Ka pansion of Tilapia, which may be its only taha (see Diamond 1984). food source. This pantropical species occurs widely in the western Pacific. Phalacrocorax melanoleucos brevicauda. Little Pied Cormorant. Manukitai (adult), LAKE: Common, although less so than F ghaghiabolu (young). minor; sex ratio similar to that of F minor; This species occurs from eastern Indonesia frequently associates with F minor. One through New Guinea and Australia to New female on the wing took a ca. 25-cm Tilapia Caledonia and New Zealand; P. m. brevi fish from the lake surface, which was cauda is endemic to Lake Te Nggano on dropped and recovered seven times before being swallowed. Rennell. LAKE: Abundant; probably outnumbers FOREST AND COAST, ROAD: Not recorded. P. carbo by 30-100 to 1; roosts of 10 to 150 AIRSTRIP: Uncommon; up to five soaring in trees over water on islets and along the high over the airstrip on 20 and 28 June. lakeshore; all active nocturnal roosts ob served were in living, shoreline Terminalia Phalacrocorax carbo novaehollandiae. Great trees; > 50% of flying individuals had heavy Cormorant. Manukitai'ugi. molt in the secondaries, and birds with pri This nearly cosmopolitan species occurs in mary molt also were observed consistently; Australia and New Guinea (P. c. novae increased activity around dusk and dawn; hollandiae), but is absent from most of the commonly foraged near shore, seldom in tropical western Pacific, including elsewhere water > 3 m deep. in the Solomons. FOREST AND COAST, ROAD, AIRSTRIP: Not LAKE: Common; groups of up to 17 flying recorded. southeast over the lake ca. 500 m from shore; Specimen Summary and Comments: Two most commonly in groups of one to three; a males and three females collected; all were few birds appeared to have retained juvenile molting a remex and/or rectrices; no evidence flight and breast feathers; may roost during of breeding; stomachs (n = 2) contained the day with P. melanoleucos but generally crustaceans (one with at least 26 shrimp up to farther from shore than P. melanoleucos. 30 nun long, stretched out), gastropods (to 324 PACIFIC SCIENCE, Volume 53, October 1999

14 mm long), non-Tilapia fish, and probable encountered on the ground or in trees and Tilapia (one piece 20 mm long). These stom snags; found in all terrestrial habitats from ach contents are consistent with those re gardens to forest; more commonly seen in ported by Bradley and Wolff (1958: 89): groups outside of forest; foraged in trash "small specimens of a fish ... and prawns heaps on discarded fruit, coconuts, and insect from lake." larvae; also turned palm fronds, likely in search of insects and lizards. Egretta sacra sacra. Pacific Reef-Heron. Ka FOREST AND COAST: Uncommon; three on gau (kagau'ugi = dark phase; kagau tea = beach; flushed singly in forest on several oc white phase). casions, usually from perches in subcanopy This species is widespread on coasts and or disturbed sites. islands in the western tropical and subtropi cal Pacific. ROAD: Common; larger groups (3-10 birds) in more disturbed areas; regularly LAKE: Rare; one dark morph in yard of flushed and seen perched at edges or in emer TR and one light morph flying along shore. gent vegetation in forest; more common and FOREST AND COAST, ROAD, AIRSTRIP: Not with increased agonistic interactions and call recorded. ing near settlements. Specimen Summary and Comments: None AIRSTRIP: Common; regularly on and collected. The single dark-morph individual around airstrip in groups of up to 30. we observed at an inland locality is consistent Specimen Summary and Comments: One with the hypothesis relating color poly male and one female collected. Stomach of morphism in day herons to differential suc cess in prey capture (Rohwer 1989). male filled with coconut and insect larvae. Female had no remex or rectrix molt, a shelled egg in oviduct, and a 22 by 21 mm Ixobrychus flavicollis woodfordi. Black Bit yolky ovum-clear evidence of breeding in tern. Ghou. June. This species is widespread from India and Southeast Asia to New Guinea and Austra Accipiter faciatus faciatus. Australian Gos lia; I f woodfordi is endemic to the Solomon hawk. Taba. Islands. The nominate subspecies of this variable LAKE, FOREST AND COAST, ROAD: Not species (11 subspecies) occurs in Timor, Aus recorded. tralia, Tasmania, and on Rennell and Bel lona. Although another subspecies occurs in AIRSTRIP: Uncommon; heard only; heard Vanuatu and New Caledonia (A. f vigilax), around MR in the hours before dawn and the species is not known from elsewhere in after dusk; calls similar to those of this the Solomon Islands. species that we heard on Isabel, Solomon Islands. LAKE: Uncommon; in both disturbed and forested (mostly edge) areas; mostly adults, Threskiornis molucca pygmaeus. Sacred Ibis. either singly or in pairs; not particularly vo Taghoa. cal but heard most days; most noticeable in This Australasian species has only two coconut plantations, where it often perched subspecies, the widespread nominate form in coconut palms; one seen flying low over and T m. pygmaeus, which is endemic to coconut palms, scaring up Aplonis insularis Rennell and Bellona. Unknown elsewhere in and A. cantoroides. the Solomons, T molucca forms a super FOREST AND COAST: Uncommon; perched species with T aethiopicus of Africa and T in canopy trees. melanocephalus of India and Southeast Asia. ROAD: Uncommon; singly or in pairs; LAKE: Common; one to three flushed or often perched in emergent or canopy vegeta- New Data OD the Avifauna of Rennell-FILARDI ET AL. 325 tiOD or snags; at least seven seen on trip from Specimen Summary and Comments: Three lake to Tinggoa. males collected. Two had enlarged testes, suggesting a breeding season that includes AIRSTRIP: Uncommon; group ofthree call early June; the third had small testes and ing, chasing, and moving about in large trees remnants ofjuvenile plumage. The conspicu along western edge of airstrip; heard sporad ous nature of this bird on Rennell (relative to ically throughout stay at airstrip. more easterly islands) likely reflects that P. p. samoensis is not extensively hunted. Pandion haliaetus melvillensis. Osprey. Magi bae. Pluvialis [dominica] fulva. Pacific Golden The subspecies melvillensis, which occurs Plover. Sibiu. from the East Indies and the Philippines This species breeds in northern Siberia and south to northern Australia, the Solomons, northwestern Alaska, and winters in Aus and New Caledonia, is often merged (e.g., tralasia and Oceania. Poole 1994) with P. h. cristatus of southern Australia and Tasmania. LAKE, FOREST AND COAST, ROAD: Not re LAKE: Uncommon; single bird each day corded. 23-27 June; two on 28 June; usually carrying AIRSTRIP: Single bird in very worn basic large Tilapia (length 20-25 em); not seen plumage on airstrip on 20-21 and 28-29 perched. June; this bird undoubtedly was oversum ROAD: Single bird perched on cliff edge mering. above Kanggava Bay. Sterna sumatrana sumatrana. Black-naped FOREST AND COAST, AIRSTRIP: Not re Tern. Gopite. corded. The nominate subspecies inhabits South east Asia and Indonesia through much of the Porphyrio porphyrio samoensis. Purple tropical western Pacific, including Rennell; Swamphen. Kagae (adult), beka (black S. s. matthewsi occurs in the western Indian juvenile). Ocean. This highly variable species is widespread from Africa to southeastern Asia, the Philip LAKE: Uncommon; usually in pairs, most pines, Australia, New Zealand, and western often in flight at intermediate distance from Oceania. Ripley (1977) united the many the lakeshore. named subspecies from western Oceania as P. p. samoensis. We agree that the birds from FOREST AND COAST: Uncommon; three fly Rennell resemble those from islands east of ing beyond the fringing reef on 24 June; five the Solomons, although a specimen we took here on 26 June. on Isabel is larger than the Rennell specimens ROAD, AIRSTRIP: Not recorded. (918 versus 765, 812 g; all adult males) and differs in plumage as well. Sterna bergii cristata. Greater Crested Tern. LAKE: Common; on ground, usually in Taga. disturbed or lakeshore habitats; most com This species is widespread in the tropical monly in pairs; one pair of adults with and subtropical Indian Ocean (four subspe adult-sized juvenile (all black with yellowish cies) and in the tropical Pacific (s. b. cris olive bill); pair ofadults on a mass offloating tata). vegetation (putative nest) on shoreline; much more vocal than on more easterly Pacific LAKE: Rare; one bird flying over lake on islands (D.W.S., pers. obs.). 28 June.

FOREST AND COAST, ROAD, AIRSTRIP: Not FOREST AND COAST, ROAD, AIRSTRIP: Not recorded. recorded. 326 PACIFIC SCIENCE, Volume 53, October 1999

Anous stolidus pileatus. Brown Noddy. trices; adult male also molting. Large Ficus Ngongo. sp. fruit (18 mm diameter), fruit pulp, and This species is pantropical; A. s. pileatus seeds in stomach and crop ofboth specimens. breeds through most of the tropical Pacific Breeding has been reported in November and Indian Oceans. (Bradley and Wolff 1958). The heavy molt in both specimens suggests either that Ptilinopus FOREST AND COAST: A flock of 24 flying does not breed during June or that breeding near a group of long-nosed spinner dolphins is asynchronous. (Stenella longirostris) just beyond the fringing reef on 24 June. Ducula pacifica pacifica. Pacific Pigeon. LAKE, ROAD, AIRSTRlP: Not recorded. Gupe. This species is widespread from islands Ptilinopus richardsii cyanopterus. Pink peripheral to New Guinea and the western spotted Fruit-Dove. Higi. Bismarcks, the Louisiade Islands, and islands This species is endemic to the Solomon peripheral to the main Solomon chain (Ndai, Islands. The nominate subspecies is restricted Rennell, Santa Cruz) east to the Cook Is to two small islands in the eastern Solomons lands. Geographic variation is poorly under (Ugi and Santa Ana); P. r. cyanopterus is stood. endemic to Rennell and Bellona. LAKE: Uncommon; usually in canopy in LAKE: Common; associated with fruiting disturbed habitats around TR and vicinity; trees; largest groups 8-10; calls ubiquitous; group of eight roosting in a snag at treefall two-part "see-saw" call heard early in morn gap after heavy rains; only vocalization ing chorus and occasionally through the noted was a single "female growl" (D.W.S., night; usually moved about as singles, pairs, pers. obs. [described as descending or flat and sometimes threes, but up to lOin and "br-r-r" by Diamond 1984]); overall much near fruiting trees and roosts; ate Ficus fruits less conspicuous than Ptilinopus; relative at mid heights (ca. 15 m), without using acro abundance of Ptilinopus: Ducula ca. 20: 1, batic maneuvers; at fruiting trees commonly suggesting that Ducula may be hunted. associated with Aplonis spp., Coracina line ata, and C. novaehollandiae. FOREST AND COAST: Common; both male type calls (single-note calls including ones FOREST AND COAST: Abundant; usually in similar to calls 1 and 2 described by Dia canopy; two roosts of three to six in stunted mond 1984) and female-type calls heard reg canopy on top of pinnacled limestone ridges; ularly from canopy; usually perched singly or fed with Aplonis spp. and Coracina lineata in in pairs. Fagraea subcanopy; both short and long calls given throughout the day; only short call ROAD: Common; usually perched singly or heard at roosts; twice observed tearing pieces in pairs on high, exposed branches. of flesh from Fagraea fruits; also seen ingest ing Ficus fruits. AIRSTRIP: Uncommon; heard (only female call) along road west of airstrip. ROAD: Abundant; primarily perched in Comments: A single nest record and canopy at road edge or flying at canopy level; stomach content analysis from Bradley and generally in pairs to groups of six, but one Wolff (1958) suggest that D. p. pacifica has a group of ca. 30 flushed. diet and breeding phenology similar to those AIRSTRIP: Common; behavioral observa of Ptilinopus richardsii. Our observations on tions similar to those in other localities. Rennell agree with survey data from Tonga Specimen Summary and Comments: One that indicate that D. pacifica increases in male and one female collected. Female is a abundance with increasing forest maturity young bird (fleshy bursa, undifferentiated (Steadman 1998, Steadman and Freifeld ovary) with extensive molt in remex and rec- 1998). New Data on the Avifauna of Rennell-FILARDI ET AL. 327

Macropygia mackin/ayi arossi. Mackinlay's Micropsitta finschii finschii. Finsch's Pigmy Cuckoo-Dove. Katogua. Parrot. Ghinei. This species is found from the Bismarck This species is found in the Bismarck Ar Archipelago east through the Solomon Is chipelago (M. f viridifrons) and the Solomon lands to Vanuatu; M m. arossi is endemic to Islands (four subspecies, including M. f fin the Solomons. schii on Rennell, Ugi, and San Cristobal).

LAKE, FOREST AND COAST: Not recorded. LAKE: Uncommon; consistently encoun ROAD: Uncommon; most often in dis tered (mostly heard) only in submature for turbed areas near mature forest; seen singly est; one netted in understory of disturbed for or in pairs and heard along road; voice as de est; rare in second growth; never recorded in scribed by Diamond (1984). gardens or open areas.

AIRSTRIP: Common; usually in pairs; in FOREST AND COAST: Common, vocaliza scrub, patchy forest, or forest. tions nearly ubiquitous; generally two to three birds; sometimes loosely associated Gallico/umba beccarii s%monensis. Gray with Gerygone flavo/ateralis; wide-ranging throated Ground-Dove. Tuu. vertically but most often in middle story to This species occurs in New Guinea, the subcanopy (8-20 m); gave short and long Admiralty Islands, the Bismarck Archipel calls regularly ("zeet" notes) when flying. ago, and the Solomon Islands; G. b. s% monensis is confined to the Solomons (Ren ROAD: Not recorded. nell, Gower, Guadalcanal, San Cristobal, Santa Ana). AIRSTRIP: Uncommon; in taller scrub and forest. LAKE, FOREST AND COAST, ROAD: Not re Foraging Observations (n = 7): Crept corded. along larger limbs or trunks (6 to > 30 cm AIRSTRIP: Rare; heard twice (a low re diameter) like a nuthatch (Sitta spp.), from peated "whooo-oop" at 1730 and 1750 4 to 15 m up. Hang-up, hang-down, and hours) in tall secondary forest along road hang-sideways maneuvers (see Remsen and west of airstrip on 28 June. Robinson 1990) prevalent. Used spike-tipped rectrices for bracing. Scraped bill along bark Lorius ch/orocercus. Yellow-bibbed Lory. Si surface, often where there were white lichens. bigi. Mostly quiet when foraging. This monotypic species is endemic to the Specimen Summary and Comments: One eastern Solomon Islands (Rennell, Savo, adult male collected. No remex or rectrix Malaita, Guadalcanal, San Cristobal, Ugi). molt. Creamy white organic mush in stom ach. Bradley and Wolff (1958) reported LAKE: Uncommon; singles or, more com stomach contents of crushed seeds, or per monly, in pairs; in forest usually within or haps remnants of fungi. above canopy; pairs seen "nuzzling" on ex posed branches on several occasions; often Geoffroyus heteroclitus hyacinthus. Singing seen foraging in coconut flowers. Parrot. Ghisua. FOREST AND COAST, ROAD: Not recorded. Geoffroyus h. heteroclitus is found in the Bismarck Archipelago and main chain of the AIRSTRIP: One pair on 21 June. Solomons; G. h. hyacinthus is endemic to Specimen Summary and Comments: One Rennell. adult female collected in coconut palm. Stomach contents include banana seeds, fruit LAKE: Uncommon; usually in groups of pulp, eight lepidopteran pupae ca. 10 mm two or three; more frequently in mature for long, and a beetle mandible. Ovary regressed est; not seen in coconut plantations or garden with minute follicles. Molt in remex. areas; usually flying over disturbed areas 328 PACIFIC SCIENCE, Volume 53, October 1999 around lake; several times spooked from can quent in understory; a trio of birds noisily opy where two or three perched silently. chased one another in young secondary scrub and gave a caroling, garbled "chur-chur FOREST AND COAST: Common; always in or chur" and more usually downslurred "pe above canopy; largest group (three) flew into urrr" calls; one of these three adopted a beg canopy tree and "disappeared" but purring ging posture with wings fanned out from calls could be heard; flight high and direct; body. flight calls include a loud series (three to Foraging Observations (n 2): Sally four) ofmusical "kee'-ur" notes (first syllable = strikes to leaves 5-6 m up in dense middle higher pitched) mixed with more nasal notes; story. one descended in an arching glide with wings in dihedral, reminiscent of rock dove (Co Caprimulgid species (unidentified) lumba livia) display flight. LAKE: Rare; one flushed from forest floor ROAD: Common; usually flying and call at dusk by D.W.S. near nets in submature ing in groups of three or four; generally flew forest on 22 June; no vocalizations heard. at canopy level in tight formation; one silent pair observed for several minutes on emer FOREST AND COAST, AIRSTRIP: Not gent snag, female perched above silent male recorded. excavating a large knot or old termitarium ROAD: Eleven different birds flushed from on a rotten branch stub. road or flying over road after dark (1900 AIRSTRIP: Common; groups of up to eight 2100 hours) on 21 June between Lavanggu flying over and near airstrip. Village and Lake Te Nggano; all seen with aid of tractor headlights. Chrysococcyx lucidus harterti. Shining Comments: No species of caprimulgid has Bronze-Cuckoo. Tangione or manutangione. been reported previously from Rennell. The This subspecies is an endemic resident on birds we observed might be the White Rennell and Bellona. Other resident popula throated Nightjar (Eurostopodus mysticalis). tions of C. lucidus occur in New Caledonia, Two factors support this identification: no the Loyalty Islands, Vanuatu, and the Santa white was seen in the wings or tail, and this Cruz Islands. The widespread populations of species is resident on many main-chain is C. I. lucidus are migratory, breeding in Aus lands of the Solomons as well as mainland tralia and New Zealand and wintering in the Australia. Lesser Sundas, New Guinea, the Bismarcks, and main islands in the Solomons. Collocalia vanikorensis lugubris. Vanikoro Swiftlet. Pekapeka. LAKE: Uncommon; heard much more This widespread and variable species (14 often than seen; recorded in subcanopy of subspecies recognized by Chantler and Hibiscus thicket (two birds), low in shrubs in Driessens 1995) is found in the Philippines, an old garden, and in forest. Sulawesi, the northern Moluccas, New FOREST AND COAST: Common; singles or Guinea, the Bismarck Archipelago, the Solo pairs in understory to subcanopy of mature mon Islands, Vanuatu, and much of Micro forest; often associated with mixed flocks of nesia (pratt et al. 1987: 218); C. v. lugubris Clytorhynchus hamlini, Gerygone flavolatera occurs throughout the Solomons. lis, and other passerines. LAKE: Abundant; foraging in amorphous groups of up to 50; usually from near ground ROAD: Rare; one in exposed canopy of large tree at old garden edge. level to 60+ m above ground; never seen higher than 100 m above ground; over lake AIRSTRIP: Common; groups of one to shore, open gardens and living areas, planta three in most habitats near airstrip, most fre- tions, old gardens, and forest; not particu- New Data on the Avifauna of Rennell-FILARDI ET AL. 329 larly vocal although occasionally heard shore; on average a more agile and erratic scolding during chases; lower flight during flier than C. vanikorensis and forages closer and after rains; not conspicuously paired. to the ground, especially along trails and for est breaks. FOREST AND COAST: Abundant; ca. 300 in swirling masses along cliff edge above Tu FOREST AND COAST: Common; primarily in hungganggo Beach; numerous birds entering forest along cliff edges; loosely associated and exiting a gap in the forest near a pre with C. vanikorensis; observed low against sumed cave entrance, emitting a typical apo vegetation on the trail gap. did chatter; commonly heard near another ROAD: Common; usually in smaller cave in primary forest but erratically encoun groups than C. vanikorensis; seemed to stay tered within forest; one netted at forest cave closer to the ground and vegetation although entrance. seen as high as treetops. ROAD: Abundant; ubiquitous along road; AIRSTRIP: Common; seen above airstrip, flying from ground to treetops but rarely gardens, roads, and forest; singles, pairs, and seen above canopy. small groups; behavioral observations as in AIRSTRIP: Abundant; behavioral observa other habitats. tions as at other localities. Comments: As noted above (see C. vani Specimen Summary and Comments: One korensis account), we found C. esculenta to adult male and one adult female collected. be less common than C. vanikorensis, in con The male's testes were minute. The female trast to information gathered two decades had a granular ovary with no enlarged fol earlier. licles. The stomach of the male contained small insect parts. As noted above, C. vani Hemiprocne mystacea woodfordiana. Whis korensis was abundant at all localities visited kered Crested-Swift. Baapenupenu. and clearly more common than C. esculenta This species occurs in the Moluccas and (see below). Diamond (1984) observed that Am Islands (H m. confirmata), New Guinea C. esculenta was slightly more common. This and west Papuan islands (nominate), the Ad discrepancy suggests that C. vanikorensis, miralty Islands (H m. macrura), the Bis which favors more open and disturbed hab marck Archipelago (H m. aeroplanes), and itats (Beehler et al. 1986; C.E.F., pers. obs.), the Solomon Islands (H m. woodfordiana may have increased in abundance in response throughout, including Rennell, except H m. to higher levels of human disturbance over carbonaria on San Cristobal). the past two decades. LAKE, FOREST AND COAST: Not recorded.

Collocalia esculenta desiderata. Glossy Swift ROAD: Rare; two birds perched in snag let. Pekapeka. along road ca. 20 m above ground; single This swift is even more widespread and bird in disturbed forest perched on exposed variable than C. vanikorensis. Chantler and snag ca. 15 m above road. Driessens (1995) recognized 31 subspecies AIRSTRIP: Common; flying at dusk over from Southeast Asia, most of Indonesia and gardens and second growth as low as 15 m the Moluccas, the Philippines, New Guinea, above ground; occasionally vocal. the Bismarck Archipelago, and the Solomon Islands south through Vanuatu to the Loy Halcyon sancta sancta. Sacred Kingfisher. alty Islands and New Caledonia; C. e. desid Ligho tai. erata is endemic to Rennell and Bellona. This subspecies breeds primarily in Aus LAKE: Common; often associated with C. tralia and migrates to Indonesia, New vanikorensis; usually in pairs or small groups; Guinea, the Bismarck Archipelago, and the seldom in open areas around TR and lake- Solomon Islands (including Rennell) during 330 PACIFIC SCIENCE, Volume 53, October 1999

the austral winter. Some populations may be Hirundo nigricans. Tree Martin. resident on Guadalcanal and San Cristobal This species breeds in Australia, Tasma (Fry et al. 1992). Other resident subspecies nia, the Lesser Sundas, the Moluccas, New occur in New Caledonia, the Loyalty Islands, Guinea, and New Caledonia. Southern pop Norfolk Island, and New Zealand. ulations (H. n. nigricans) migrate north as far as the Solomon Islands. LAKE, FOREST AND COAST, ROAD: Not re corded. LAKE: Rare; one seen twice soaring over AIRSTRIP: Three perched together on wire; the canopy, associated with Collocalia vani all had very buffy flanks and some buff on korensis. Although the pale rump was not collar; all sat still and silent, whereas the res seen because of the angle and distance, the ident breeder H. chloris called incessantly. hirundine flight and shape (slightly forked tail), and light underparts contrasting with Halcyon chloris amoena. White-collared the dark back and cap, leave little doubt Kingfisher. Ligho. that this bird was Hirundo nigricans. The This species is widespread and extremely only other swallow known from the Solomon variable, with 50 subspecies recognized (Fry Islands is H. tahitica, which is much darker et al. 1992) from northern Africa across below, has a longer forked tail, and different southern Asia to Melanesia and Australia flight. and then to western Micronesia and western FOREST AND COAST, ROAD, AIRSTRIP: Not Polynesia; H. c. amoena is endemic to Ren nell and Bellona; nine other subspecies occur recorded. Comments: This is the first record of this in the Solomons. species or any swallow for Rennell Island. LAKE: Common; usually singly or in pairs; Hirundo nigricans winters "occasionally in not as vocal as in other areas on Rennell; the Solomon Islands" (Mayr 1945) and has perched at any height in new growth, coco been recorded from Guadalcanal. nut plantations, forest edge, and closed for est; probably territorial; several observations Coracina lineata gracilis. Yellow-eyed of birds carrying orthopterans. Cuckoo-shrike. Lighobai. This polytypic species (10 subspecies) is FOREST AND COAST: Uncommon; encoun found in New Guinea and surrounding tered twice in forest crossing trail; one netted islands, the Bismarck Archipelago, and the in secondary forest; one seen ingesting or Solomon Islands. Endemic to Rennell and thopteran in tree at cliff edge. Bellona, C. I. gracilis is the only subspecies ROAD: Not recorded. with males retaining femalelike ventral bar ring (Mayr 1945). AIRSTRIP: Common; very vocal in dis turbed habitats; singly, in pairs, or groups of LAKE: Uncommon; one group of six in three; at all levels of vegetation, often on ex Ficus in secondary forest, and sporadic posed branches. flyovers. Specimen Summary and Comments: Three males and three females collected. Their re FOREST AND COAST: Common; heard and productive condition indicates that H. c. seen regularly within and above canopy, but amoena was not breeding in late June. Brad not in understory; commonly in groups of ley and Wolff (1958) reported a nest with four to six, gleaning fruit in canopy; six COIn three nestlings in early November. Stomachs ing in to roost in snag in primary forest (all (n = 3) contained beetles (heads, elytra), or three specimens collected from this group); thopterans (mandibles), spiders (chelicerae occasionally associated with Aplonis sp. and fangs), and other arthropod parts. Brad ley and Wolff (1958) also reported land snails ROAD: Common; usually in groups of in the stomach of one bird. three to eight flying just above canopy or New Data on the Avifauna of Rennell-FILARDI ET AL. 331 across canopy gaps, often involving emergent mature closed forest; not in open gardens or Ficus sp. other habitats without tall canopy; "chuck chuck-chuck" call as described by Diamond AIRSTRIP: Uncommon; a group of at least (1984), reminiscent of American Robin (Tur five in canopy of emergent Ficus sp. with Du dus migratorius); no song identified. cula pacifica, Ptilinopus richardsii, and Aplo nis cantoroides; one on bare branch above FOREST AND COAST: Common; singles or second growth; heard sporadically. pairs heard and seen regularly, never above Specimen Summary and Comments: Two 2m. males and one female collected. None in ROAD: Uncommon; in undergrowth or fly breeding condition. Bradley and Wolff (1958) ing low across the road. reported an October/November clutch oftwo from Rennel!. The stomachs (n = 2) con AIRSTRIP: Uncommon; in more mature tained fruit pulp and seeds (including Ficus forests away from airstrip. sp.), beetle parts (elytra, heads, bodies), and a Specimen Summary and Comments: Four phasmid. males and two females collected. The two fe males were not of breeding age because they Coracina novaehollandiae. Black-facea had incomplete skull ossification, immature Cuckoo-shrike. ovaries, and bursae. All four males had en This species breeds in Australia and Tas larged testes. The three males collected by mania, and migrates in the austral winter to Bradley and Wolff (1958) in November also northern Australia, the Lesser Sundas, New had enlarged testes. This suggests a pro Guinea, and the Solomon Islands. It is part longed breeding season on Rennell. One male of the C. caledonica superspecies that ranges had light body molt, and another had pri from the Himalayas to Australia and New maries sheathed at base. Females were not Caledonia (Sibley and Monroe 1990). molting, except one had a single secondary in sheath. Stomachs (n = 6) were empty. Brad LAKE: Rare; two sightings of one bird in ley and Wolff (1958) identified millipedes, a snag near fruiting Ficus; no evidence that larvae, adult beetles, and small snails in their more birds were present; in both cases asso specimens. ciated with a flock of Aplonis cantoroides and A. insularis. Gerygone flavolateralis cUrina. Fantail Ger FOREST AND COAST, ROAD, AIRSTRIP: Not ygone. Lokeloke. recorded. This species occurs on New Caledonia (G. Comments: This is the first record of C. f flavolateralis), the Loyalty Islands (G. f novaehollandiae for Rennell. The subspecies roxi, G. f lifuensis), northern Vanuatu and melanops winters in the Solomon Islands the Banks Islands (G. f correiae), and Ren (Mayr 1945). nell, where G. f cUrina is endemic. The spe cies is not known elsewhere in the Solomons. Turdus poliocephalus rennellianus. Island This distribution is nearly identical to that of Thrush. Gagango. Myiagra caledonica (see below). The hypervariable Turdus poliocephalus LAKE: Abundant; most often in groups of (50 subspecies in Ripley 1964) occurs from two to four; vocal throughout day; promi Southeast Asia and Indonesia east to Tonga nent member of morning chorus; occurs pri and Western Samoa (Steadman 1993); T p. marily in understory but also in higher strata; feminina, endemic to Rennell, is one of four several birds carrying pieces of moss and subspecies in the Solomons (Bougainville, rootlets; common anywhere with standing Guadalcanal, and Kolombangara each also woody vegetation, including garden edges, with an endemic form). coconut plantations, disturbed and older for LAKE: Uncommon (based on net results); est; often in mixed flocks with Woodfordia pairs in understory of shaded scrub or sub- superciliosa, Zosterops rennelliana, Rhipidura 332 PACIFIC SCIENCE, Volume 53, October 1999 rennelliana, Clytorhynchus hamlini, and FOREST AND COAST: Uncommon, although loosely with Myzomela cardinalis. more common than in more disturbed habi tats; from understory up to 15 m; usually in FOREST AND COAST: Abundant; behavior pairs, loosely associated with mixed flocks; and group size similar to that given above. the only vocalizations noticed were harsh ROAD: Abundant; consistent with above scolding calls. observations. ROAD: Uncommon; consistent with be havioral notes from other localities. AIRSTRIP: Abundant; consistent with above observations. AIRSTRIP: Uncommon; group of four Foraging Behavior: A very active forager, along airstrip in young second growth; usu almost always using jumps or short sally ally 2-8 m above ground. strikes or hovers (5-50 em) to live leaves for Foraging Behavior: Very active foraging, insect prey. Some hovers were protracted (to changing perches frequently and spreading its 2-3 sec), and the birds often gave audible bill tail, and using short to midlength (15 snaps. 100 em) sally strikes to take flying insects. Specimen Summary and Comments: Four Appeared to flush and then chase prey. Some males and five females collected. Specimens sallies became protracted flutter chases. were a mixture of breeding and nonbreeding Specimen Summary: Four males and one birds although all lacked bursae and had female collected. None in breeding condition. fully ossified skulls. Bradley and Wolff (1958) found several nests in November, and the Clytorhynchus hamlini. Rennell Shrikebill. presence of reproductively active birds in our Ghoghobiu. sample suggests a prolonged breeding season. This monotypic species is endemic to The presence of adult males with either en Rennell. larged or small gonads points either to asyn LAKE: Common; singles or groups of two chronous breeding or to the presence of or three (adults with juveniles) in understory; "floater" males (Brown 1969) in the popula never more than two adults together; any tion. Stomachs (n 3) contained spiders and = habitat with developed understory; often as spider parts (fangs and chelicerae), lep sociated with Gerygone flavolateralis, Zoster idopteran-type larvae, beetle elytra, and a ops rennelliana, and Woodfordia superciliosa, hymenopteran head. Bradley and Wolff but occasionally away from flocks; readily at (1958) reported small beetles in stomachs. tracted to "pishing."

Rhipidura rennelliana. Rennell Fantail. FOREST AND COAST: Common; generally in Maghighape. mixed flocks with Z. rennelliana, Myiagra cal Endemic to Rennell, R. rennelliana is a edonica, Pachycephala pectoralis, Chrysococ member of a superspecies that includes R. cyx lucidus, G. flavolateralis, and W superci drownei on Guadalcanal and Bougainville; liosa. R. tenebrosa on San Cristobal; R. spilodera ROAD: Uncommon; consistent with be from Vanuatu, the Banks Islands, New Cal havioral notes from other localities. edonia, and Fiji; R. personata of Fiji; and R. nebulosa in Western Samoa (Mayr 1986, AIRSTRIP: Uncommon; behavioral obser Sibley and Monroe 1990). vations as at other localities; more associated with forested areas than in other localities; LAKE: Uncommon; generally in closed observed only away from airstrip. canopy stands, from scrubby second growth Foraging Behavior: Difficult to see well as to submature forests; in scrub usually 1-3 m it moved sluggishly through rather dense above ground, but up to 15 m in tall forests; understory; only foraging maneuver observed usually in closely associated pairs, sometimes was a reach up and probe into a suspended groups of three. and curled dead leaf. New Data on the Avifauna of Rennell-FILARDI ET AL. 333

Specimen Summary and Comments: Five The incredibly polytypic Pachycephala males and five females collected. Half of pectoralisfcaledonica assemblage (73 subspe these are young birds with bursae and less cies of P. pectoralis in Mayr 1967; also see than 100% skull ossification. The five adults Sibley and Monroe 1990) is found in Walla had small testes or ovaries without enlarged cea, Australasia, and southwestern Oceania; follicles. The five young birds suggest breed P. p. feminina is endemic to Rennell. Several ing within several months before our arrival. other subspecies occur in the Solomons. Diamond (1984) reported nest construction during October, although Bradley and Wolff LAKE, ROAD, AIRSTRIP: Not recorded. (1958) had no evidence of breeding in speci FOREST AND COAST: Uncommon; only men data from October and early November. within well-developed, closed-canopy forest; Stomach contents were dominated by beetle a core member in mixed-species understory and orthopteran parts (mandibles, elytra, flocks with Myiagra caledonica, Zosterops legs, etc.). Spider chelicerae were also found. rennelliana, and Clytorhynchus hamlini; nota Bradley and Wolff (1958) reported beetles bly silent (uncharacteristic for P. pectoralis and other insects in stomachs. [D.W.S., pers. obs.]); fragment of typical song (described in Diamond 1984) heard Myiagra caledonica occidentalis. Broad-billed only once from forest understory; one bird Flycatcher. Tangitangivilage. successfully lunged (cf. Remsen and Robin This species is found in New Caledonia son 1990) for orthopterans. (M. c. caledonica), the Loyalty Islands (M c. Comments: Diamond (1984) recorded P. viridinitens), Vanuatu (M. c. marinae), the pectoralisfeminina as abundant in forest with Banks and Torres Islands (M. c. melanura), a common, conspicuous call. In contrast, we and Rennell, where M. c. occidentalis is en found P. p. feminina decidedly uncommon, demic. This distribution nearly matches that even in appropriate habitat; they were not of Gerygone flavolateralis; it is also absent vocal or conspicuous. Because Bradley and elsewhere in the Solomon Islands. Wolff (1958) reported nesting in Octoberf November, Diamond's observations (made LAKE: Rare; one perched alone in under story (2.5 m) of disturbed forest. in October) probably reflect increased vocal activity of this species during the breeding FOREST AND COAST: Uncommon; seen on season. several occasions in forest with mixed flocks (tightly or loosely associated), usually low in Myzomela cardinalis sanfordi. Cardinal undergrowth. Honeyeater. Baghigho (male, baghigho kuga; female, baghigho ugupoko). ROAD, AIRSTRIP: Not recorded. This polytypic species (15 subspecies [Sal Foraging Observations: In mature forest omonsen 1967]) is widespread in Micronesia on 26 June (1100-1115 hours), an adult male and occurs in scattered populations in eastern made eight long sallies (ca. 1-3 m) from Melanesia and western Polynesia (to Samoa, perches 1-3 m above ground; the sallies, and formerly Tonga [Steadman 1993]); M c. which terminated in brief hovers at leaf sub sanfordi is endemic to Rennell; the only other strates (sometimes touching feet on leaves), populations of M. cardinalis in the Solomons were more horizontal than vertical; the bird are of M c. pulcherrima on San Cristobal never returned to its original perch. and Ugi. Comments: Diamond (1984) reported this species nesting in October although two LAKE: Abundant; seen and heard adults collected by Bradley and Wolff (1958) ("churlp!" and scold notes) constantly in all in November showed no evidence ofbreeding. habitats; adult males often on exposed perches above leafy canopy giving musical Pachycephala pectoralis feminina. Golden "cher-dert" or "cher-dert-dert" calls, the Whistler. Taataga. "derts" slightly lower pitched; singly, in 334 PACIFIC SCIENCE, Volume 53, October 1999 pairs, or pairs associated with ·single young; did not analyze stomach contents for nectar used a variety of exposed (mainly adult or pollen. males) and protected perches; also on islets in lake and often flying over the lake; in Woodfordia superciliosa. Woodford's White mid-level (2-3 m) of scrub up into emergent eye. Ghaga. canopies, coconut plantations, and exposed The two species of Woodfordia are large garden trees; loosely associated with mixed white-eyes with narrow distributions; W su flocks of Woodfordia superciliosa and to a perciliosa is endemic to Rennell, whereas W lesser extent Gerygone flavolateralis; in fruit lacertosa is endemic to Ndende in the Santa ing trees with Ptilinopus richardsii, Coracina Cruz Islands, about 600 km ENE. lineata, W superciliosa, G. flavolateralis, and LAKE: Abundant in all vegetation types; Aplonis cantoroides; kept more closely to the generally in groups of four to eight; most canopy in mature forests. commonly with Gerygone flavolateralis; FOREST AND COAST: Common; generally at sometimes with Zosterops rennelliana and higher levels in forest than in more disturbed Myzomela cardinalis; appeared less common habitats; less vocal in submature to mature in more mature forest; seen crossing gaps of forest and along cliff edges; in fruiting tree all kinds; most often 2-8 m above the (Fagraea sp.) with P. richardsii, C lineata, ground but occurs at all levels including can Aplonis spp., and mixed flocks of W superci opies of emergent Ficus trees; generally very liosa and G. flavolateralis. vocal; larger groups (6-10 birds) occasionally exploded into musical chatter as if mobbing ROAD: Common; perhaps more abundant something; groups often emitted soft contact than any other passerine along the road; reg notes reminiscent of contact calls of Pitohui ularly seen perched and flitting about road spp. and Pomatostomus isidorei within side vegetation and the visible canopy layer. mixed-species foraging flocks in New Guinea (C.E.F., pers. obs.); sometimes gave agitated, AIRSTRIP: Abundant; highly vocal, both scolds and whistles; frequent chasing (male metallic notes in a long series (possibly an male and female-female); other behavioral alarm call); apparently frequent vocal mim observations as at other localities. icry between Zosterops rennelliana and this Foraging Behavior: Foraged on both nec species (see Diamond 1984). tar and insects, using gleans and occasionally FOREST AND COAST: Abundant, although short (ca. 20 cm) sally strikes to live vegeta somewhat less so than around the lake; simi tion. lar group sizes nearly always moving in the Specimen Summary and Comments: upper understory but also at higher and low Twelve males and six females collected. Eight er levels; in fruiting trees with Ptilinopus birds had bursae and incomplete skull ossifi richardsii, Coracina lineata, M. cardinalis, cation. No adults had enlarged gonads. and Aplonis spp., as well as G. flavolateralis, Bradley and Wolff (1958) reported a male Z. rennelliana, and Clytorhynchus hamlini; with enlarged gonads in October/November also sporadically in mixed flocks of varying and found one active nest. Eight of their 18 species composition throughout the forest. specimens were classified as juveniles, and one was a nestling, suggesting a breeding ROAD: Common; behavior as at other season in the austral spring. Stomachs localities. (n = 4) contained mostly insect parts, in AIRSTRIP: Abundant; behavior as at other cluding beetle elytra and heads (weevils and localities. other families), lepidopteran larvae man Foraging Behavior: Foraged at a variety of dibles, and hymenopteran bodies and wings. forest strata and in open growth or disturbed Also found were seeds, pollen, and a few vegetation; most frequently observed eating spider chelicerae. This species undoubtedly fruits (including melastomes, Macaranga har relies heavily on nectar on Rennell, but we veyana, Pipturus argenteus), but also visited New Data on the Avifauna of Rennell-FILARDI ET AL. 335

flowers for nectar and inspected dead leaves, than in Woodfordia superciliosa; all foraging vines, and leafaxils for arthropods. observations 1-6 m above ground; con Specimen Summary and Comments: Seven sistently inspected dead leaves (n = 11); also males and II females collected. Gonads ofall inspected flowers (Rubiaceae) and live leaves; II adults indicated that W superciliosa was frequently used hang-sideways (n = 3) and not breeding in late June. Three had skulls hang-down (n = 4) maneuvers from hori < 50% ossified, suggesting fledging within zontal to vertical perches to inspect leaves or several months. Diamond (1984) observed probe into curled dead leaves. many begging juveniles in October. Bradley Specimen Summary and Comments: Four and Wolff (1958) noted two nests and one males and two females collected. Our sample clutch of two in October/November. Stom contains breeding and nonbreeding adults, achs (n = 4) contained several types of seeds, and two birds with incomplete skull ossifica fruit skin and pulp (including papaya), insect tion and bursae. Two males had enlarged parts (beetle elytra, lepidopteran larvae man testes, and one female had a shelled egg in dibles), a scorpion abdomen, and spider her oviduct and two ruptured follicles (clutch fangs. size >2). Both Diamond (1984) and Bradley and Wolff (1958) reported active nests in Zosterops rennelliana. Rennell White-eye. October/November. The combined observa Suusuuubagu. tions suggest that 20 rennelliana has a pro This species is endemic to Rennell. Other longed and perhaps asynchronous breeding members of the Zosterops griseotinctus su season, spanning from at least June to No perspecies (see Mayr 1967, Sibley and Mon vember and likely longer. Stomachs (n = 2) roe 1990) occur on small islands in the contained many small seeds (ca. 30 l-mm central Solomons (20 vellalavella on Vella diameter seeds in one stomach and > 150 in Lavella and Mbava, 20 luteirostris on Ghizo, the other), beetle parts, spider fangs, and the 20 kulambangrae in the New Georgia group, mandible of a lepidopteran larva. and 20 splendidus on Ranongga) and off New Guinea and the Bismarck Archipelago (20 Aplonis cantoroides. Singing Starling. Ghaa griseotinctus). pilu-ghae. This monotypic species (if Aplonis crassa LAKE: Common; usually in pairs, occa of Tanibar Island is treated as specifically sionally three, but not seen alone; generally distinct [e.g., Amadon 1962, Sibley and 1-6 m above the ground; song with much Monroe 1990]) is found on New Guinea and spacing between phrases, heard primarily at surrounding islands, the Bismarck Archipel dusk and dawn, and sporadically during day ago, and the Solomon Islands. light; also a chattery contact call; rare in early second growth; more common with in LAKE: Common, but patchily distributed; creasing age of woody vegetation; associated often in vicinity of roosts or fruiting trees, or regularly with Woodfordia superciliosa and/ flying in compact groups of 10-15 birds in or Gerygone flavolateralis, sometimes with the early morning or late afternoon; in fruit Clytorhynchus hamlini. ing trees often with Ptilinopus richardsii, Cor acina spp., and Aplonis insularis; eating fruits FOREST AND COAST: Common; generally in of Fagraea and Ficus; distribution seemed to pairs both within and outside of mixed depend on presence of fruiting trees more flocks; usually at 2-10 m from understory to than any other habitat variable; not seen in subcanopy. understory; ratio of adult: young ca. 3 : 1. ROAD: Common; but in small overall FOREST AND COAST: Uncommon; with Pti numbers; behavior as at other localities. linopus richardsii, Coracina lineata, A. insula AIRSTRIP: Common; behavior as at other ris, and mixed flocks of Woodfordia superci localities. liosa, Myzomela cardinalis, and Gerygone Foraging Behavior (n = 13): Less varied flavolateralis in and around fruiting trees, es- 336 PACIFIC SCIENCE, Volume 53, October 1999 pecially Fagraea sp.; observed tearing flesh Comments: Bradley and Wolff (1958) from Fagraea fruits; not very vocal. found this species more common on the land around Lake Te ~ggano than A. cantoroides ROAD: Common; several flocks of 8-12 and documented A. insularis nesting in birds appeared to be postbreeding flocks stumps of coconut trees. They also collected based upon the prevalence of juveniles; also three specimens, including one juvenile, in perched in groups on exposed snags and ~ovember and examined a clutch of three sparse-canopy trees, once with putative A. in eggs. sularis.

AIRSTRIP: ~ot recorded. Comments: Bradley and Wolff (1958) DISCUSSION documented an early ~ovember nest with four young in a hole in the coral rock on an Several novel observations merit addi islet in Lake Te ~ggano and reported that tional discussion and further confirm that this species kept mainly to the islets. They basic fieldwork can contribute to our under collected a female with enlarged gonads and standing of how Rennell's avifauna is chang a juvenile male. Previously, A. cantoroides ing over time. had been recorded only once from Rennell (Mayr 1945) and was regarded as a straggler. General Patterns ofBreeding Aplonis insularis. Rennell Starling. Ghaapilu In combination with previous work, our mouku. specimen data suggest that many land birds This species is endemic to Rennell and on Rennell have prolonged breeding seasons Bellona. Amadon (1962) stated that it may typical of those of lowland tropical regions be a race of Aplonis feadensis, which occurs (Gill 1995, and references therein). Although on small islands in the Bismarcks and Solo virtually no ornithological research has been mons (Fead, ~issan, Ontong Java). Sibley undertaken on Rennell from January to and Monroe (1990) considered A. feadensis May, our specimen evidence suggests that and insularis to be a superspecies. Clytorhynchus hamlini, Woodfordia super ciliosa, and Myzomela cardinalis probably LAKE: Uncommon; always associated breed during some portion of those months with A. cantoroides; commonly two to four (but were not in breeding condition in late individuals appearing to be A. insularis June). On the other hand, specimens of Zos (shorter tail and stubbier bill) in flocks of 8 terops rennelliana, Gerygone flavolateralis, 12 birds; no observed behavioral differences and Turdus poliocephalus in breeding condi between A. insularis and A. cantoroides; calls tion were collected during our stay. Diamond different from those of A. cantoroides-a (1984) and Bradley and Wolff (1958) both rapid dry series of monotonic, metallic clinks reported October/~ovember breeding in and clicks; the presumed song is two short most species ofland birds, including the three series of notes like a squeaky bicycle wheel we observed breeding in June and the three "wreee-eee-eee-eee," pause, "eee-eee." others that we infer to have bred just before FOREST AND COAST: Uncommon; associ our arrival. These patterns suggest a pro ated with A. cantoroides; general habits longed (8+ months) or bimodal breeding seem similar to those of A. cantoroides. season for many species of land birds on Rennell. It is possible that some species (T ROAD: Rare; found once in a flock of A. poliocephalus and Z. rennelliana) may breed cantoroides; relative abundance reported throughou~ the year, and others (W super here likely an artifact of the tractor ride and ciliosa and M. cardinalis) may have a non our uncertainty as to the field identification breeding period during the early austral win of this species. ter ending sometime in June or July. AIRSTRIP: ~ot recorded. According to local inhabitants, many of New Data on the Avifauna of Rennell-FILARDI ET AL. 337

the aquatic birds of Lake Te Nggano bred described by Diamond and that Myzomela before our arrival. The small cormorant appeared to be only loosely associated with Phalacrocorax melanoleucos and frigatebirds mixed-species flocks. Clytorhynchus was an (Fregata minor and F. ariel) clearly were not occasional member of the ZosteropsfWood breeding, and none of the roosts or islets we fordia flocks but was encountered more often observed harbored nesting birds. The two as a core member in a different type of specimens of Phalacrocorax carbo, however, mixed-species flock that consisted of Pachy had gonad and plumage conditions suggest cephala pectoralis, Myiagra caledonica, and ing that they would breed soon, when it was Gerygone flavolateralis. Chrysococcyx lucidis unlikely that any of the other aquatic species and Zosterops rennelliana appeared to be would be breeding. more peripheral members of this last type of mixed-species flock. Dawn Chorus and Mixed-Species Flocks New Observations In general, our observations of dawn cho ruses and mixed-species flocks on Rennell are We observed three species previously un consistent with those ofDiamond (1984). We recorded from Rennell. What appeared to be stress that both Diamond's and our fieldwork a single Black-faced Cuckoo-shrike, Coracina on Rennell were for short periods (5-13 novaehollandiae, was observed several times. October for Diamond and 20-30 June for An Australian breeder, C. novaehollandiae us). The dawn chorus on Rennell is rather reaches the Solomons only sparingly in the monotonic, consisting largely of Zosterops austral winter (Mayr 1945). We also re rennelliana, Gerygone flavolateralis, Myzo peatedly observed a putative species of cap mela cardinalis, Woodfordia superciliosa, and rimulgid on the road and on forest trails near occasionally Ptilinopus richardsii. The order the lake (most probably Eurostopodus mysti by which birds began to sing before and calis) and twice observed a Tree Martin through dawn was consistent with that re (Hirundo nigricans). We were unable to col ported by Diamond (1984), although we re lect specimens from any of these three spe corded a somewhat different species compo cies. In light of the evidence for colonization sition. The predawn vocal activity described of Rennell in recent decades by Phalacro by Diamond of Rhipidura rennelliana, Clyto corax carbo and Aplonis cantoroides (see rhynchus hamlini, and Zosterops rennelliana below), it is possible that some of the new was conspicuously absent during our field records of nonbreeding birds might also rep work, although all three species were present resent the early stages ofonce-vagrant species at our sites. It seems likely that these differ establishing resident populations. ences reflect seasonal variation in vocal ization. Neither R. rennelliana nor C. hamlini Changes during Recent Decades were breeding during our stay, although some Z. rennelliana were (see species ac Our observations suggest two major counts). Differing vocal activity may also be changes in the avifauna of Rennell since Di related to differences in the habitats we amond visited the island in 1976. First, Pha sampled. lacrocorax carbo is increasing in abundance. Our findings on mixed-species flocks were Reported initially as an Australian vagrant consistent with those of Diamond (1984): by Diamond (1984), the marked population flocks with Woodfordia superciliosa, Zoster increase and breeding of this cormorant ops rennelliana, and Rhipidura rennelliana as (Gibbs 1996) follows the introduction of the regular members and Clytorhynchus hamlini fish Tilapia mossambica into Lake Te and Myzomela cardinalis as occasional Nggano in 1957. We have no evidence that members. Our observations suggest that Rhi P. carbo feeds on anything but Tilapia, or pidura was a more occasional than regular that it uses coastal or marine environments member of the ZosteropsfWoodfordia flocks on Rennell. Thus, the proliferation of Tilapia 338 PACIFIC SCIENCE, Volume 53, October 1999

TABLE 1

REsIDENT SPECIES OF BIRDS PREVIOUSLY REcORDED ON RENNELL ISLAND THAT WE DID NOT REcORD DURING 20-30 JUNE 1997

SCIENTIFIC NAME COMMON NAME LATEST RECORD ,POSSmLE EXPLANATION FOR LACK OF RECORD

Anas superciliosa pelewensis Australian Black Duck 1965, 1976 Extirpated by disruption offood supply Anas gibberifrons remissa Gray Teal 1928 Extirpated by disruption offood supply Porzana tabuensis Sooty Rail 1963 Overlooked?; extirpated by rats? Sterna anaethetus anaethetus Bridled Tern 1976 Overlooked because it resides in middle of lake or on remote islets Caloenas nicobarica nicobarica Nicobar Pigeon 1930 Rare or extirpated? Tyto alba crassirostris Barn Owl 1930 Rare?; little night work?

may have led to the establishment of breed species that prefer open or disturbed habitats ing populations of a formerly vagrant spe (such as Hirundo nigricans) may also be can oies. Monitoring how changes in the aquatic didates for colonization. Because of the ex ecosystem affect bird populations is impera ceptional endemism and unusual composi tive to conservation of the Rennellese avi tion of Rennell's avifauna, the impacts of fauna. A consideration of the potential newly colonizing species are worthy of long impact of introducing exotic species should term monitoring. guide future management decisions. The process of successful colonization by A second indication of change concerns vagrant species following anthropogenic dis the starling Aplonis cantoroides. Generally, turbance probably has been occurring in A. cantoroides is associated with shoreline Oceania for thousands of years. For exam coconut plantations, human settlements, and ple, the fossil record of rails in remote Oce other types of disturbed or edge habitats. ania shows that the arrival of widespread, Because it is rare or absent in true forest, volant species (Porzana tabuensis, Gallirallus Mayr (1945) explained his single observation philippensis, Porphyrio porphyrio) occurred on Rennell as accidental. In the 1950s, Brad only after human arrival and resultant defor ley and Wolff (1958) collected two adults and estation beginning 3000 yr ago (Steadman reported an active nest in November on a 1993, 1995). Previous to that time, each is lake islet. By the 1970s, Diamond (1984) en land was inhabited by endemic flightless spe countered this species regularly around the cies of rails. lake but never more than ca. 400 m from the lakeshore. We observed A. cantoroides both around the lake and along most of the road, What Is Missing Today from Rennell's but observations ceased as we approached Avifauna the western end of the island. Habitat alter ation associated with villages near the lake We did not find six resident species pre and on the cross-island road may be enabling viously reported from Rennell (Table 1). As a population expansion of this starling. Diamond (1984) speculated, the presence of The recent population increases of Phala Tilapia undoubtedly has affected the aquatic crocorax carbo and Aplonis cantoroides food web of Lake Te Nggano and probably portend the importance of vagrant species is responsible for the apparent loss of Ren on islands subjected to increased human nell's two resident species of ducks. Over disturbance. That these species colonized hunting is unlikely to explain the extirpation Rennell suggests that human-instigated of these ducks because large parts of the lake changes in the aquatic or terrestrial land are seldom visited. With our limited field scapehave enabled former vagrants to es time and the small portion of the island we tablish resident populations. Other vagrant explored, we may simply have overlooked New Data on the Avifauna of Rennell-FILARDI ET AL. 339

Porzana tabuensis, Sterna anaethetus, and LITERATURE CITED Tyto alba. Because Caloenas nicobarica typi cally is nonvocal but can be visually conspic AMADON, D. 1962. Family Sturnidae, Star uous, lack of record since 1930 suggests ex lings. Pages 75-121 in E. Mayr and J. C. treme rarity or possible extinction. Specific Greenway, eds. Check-list of birds of the searches for these species should be made to world, Vol. XV. Museum of Comparative confirm their status. Zoology, Cambridge, Massachusetts. Rennell is unusual among major islands in BALOUET, J.-C., and S. L. OLSON. 1989. Fos Oceania in that its birdlife was well surveyed sil birds from late Quaternary deposits in right at the time of the first major Western New Caledonia. Smithson. Contrib. Zool. contact. There is no fossil record of birds for no. 469. Rennell, so our assessment of which birds BEEHLER, B. M., T. K. PRATT, and D. A. may have been lost during prehistoric human ZIMMERMAN. 1986. Birds of New Guinea. occupation is purely speculative and based Princeton University Press, Princeton, on the species recorded in prehistoric sites New Jersey. from nearby areas of Oceania such as New BRADLEY, D., and T. WOLFF. 1958. The birds Ireland (Steadman et al. 1999), New Cal of Rennell Island. Nat. Hist. Rennell lsI., edonia (Balouet and Olson 1989), Tikopia Br. Solomon lsI. 1: 85-120. and Anuta (Steadman et al. 1990), and Ton BROWN, J. L. 1969. Territorial behaviour in ga (Steadman 1993, 1995). We consider these population regulation in birds: A review taxa to be among those most likely to be and re-evaluation. Wilson Bull. 81: 293 identified if prehistoric bone deposits were 329. found on Rennell: procellariids, tropicbirds, CHANTLER, P., and G. DRIESSENS. 1995. megapodes, flightless rails in any of five gen Swifts: A guide to the swifts and treeswifts era (Porzana, Gallirallus, Nesoclopeus, Galli of the world. Pica Press, Sussex, u.K. nula, Porphyrio), other species of Ducula and DIAMOND, J. M. 1984. The avifauna of Ren Gallicolumba, Aegotheles, Eclectus, Charmo nell and Bellona islands. Nat Hist. Rennell syna, Corvus, and a meliphagid larger than lsI., Br. Solomon lsI. 8: 127-168. Myzomela. Additional prehistoric losses on DIAMOND, J. M., and E. MAYR. 1976. Spe Rennell might include eagles, strigid owls, cies-area relation for birds of the Solomon frogmouths, hornbills, pittas, and other birds Archipelago, and the paradox of the great that occur today no further east in the Pacific speciators. Proc. Natl. Acad. Sci. U.S.A. than the main chain of the Solomons. 73: 2160-2164. FRY, C. H., K. FRY, and A. HARRIS. 1992. Kingfishers, bee-eaters & rollers. Princeton University Press, Princeton, New Jersey. ACKNOWLEDGMENTS GIBBS, D. 1996. Notes on the Solomon Island birds. Bull. Br. Ornithol. Club 116: 18-25. We thank the government of the Solomon GILL, F. B. 1995. Ornithology. W. H. Free Islands for granting us permission to do re man and Company, New York. search in their fascinating country. In partic HADDEN, D. 1981. Birds of the North Solo ular, we are grateful for assistance provided mons. Wau Ecology Institute Handbook by Audrey Rusa and Moses Biliki. We also no. 8. Wau, Papua New Guinea. thank our Rennell Island contacts (S. Ka MAYR, E. 1931. A systematic list of the birds taha, M. Taieha, M. Tauniu) for arranging of Rennell Island with description of new food and lodging during our stay, and per species and subspecies. Am. Mus. Novit. mission to work on local lands. We are 486: 1-29. grateful to J. M. Diamond, S. Drovetskiy, A. ---. 1945. Birds of the Southwest Pacific. Edwards, S. Rohwer, and G. Voelker for The Macmillan Company, New York. comments on an early draft of the manu --. 1967. Subfamily Pachycephalinae, script. Whistlers or Thickheads. Pages 3-51 in R. 340 PACIFIC SCIENCE, Volume 53, October 1999

A. Paynter Jr., ed. Check-list of birds of SALOMONSEN, F. 1967. Family Meliphagidae, the world, Vol. XII. Museum of Compar Honeyeaters. Pages 338-450 in R. A. ative Zoology, Cambridge, Massachusetts. Paynter Jr., ed. Check-list of birds of the --. 1986. Subfamily Rhipidurinae (Aus world, Vol. XII. Museum of Comparative tralasian). Pages 530- 556 in E. Mayr and Zoology, Cambridge, Massachusetts. G. W. Cottrell, eds. Check-list of birds of SIBLEY, C. G., and B. L. MONROE JR. 1990. the world, Vol. XI. Museum of Compara Distribution and taxonomy of birds of the tive Zoology, Cambridge, Massachusetts. world. Yale University Press, New Haven, MAYR, E., and H. HAMLIN. 1931. Notes on Connecticut. the geography of Rennell Island and the STEADMAN, D. W. 1993. Biogeography of ecology of its bird life. Am. Mus. Novit. Tongan birds before and after human 488: 1-11. impact. Proc. Natl. Acad. Sci. U.S.A. POOLE, A. F. 1994. Family Pandionidae (Os 90: 818-822. prey). Pages 42-51 in J. Del Hoyo, A. El ---. 1995. Prehistoric extinctions of liott, and J. Sagartal, eds. Handbook of Pacific Island birds: Biodiversity meets the birds of the world, Vol. 2. Lynx Edi zooarchaeology. Science (Washington, tions, Barcelona, Spain. D.C.) 267: 1123-1131. PRATT, H. D., P. L. BRUNER, and D. G. ---. 1998. Status ofland birds on selected BERRETT. 1987. The birds of Hawai'i and islands in the Ha'apai Group, Kingdom of the tropical Pacific. Princeton University Tonga. Pac. Sci. 52: 14-34. Press, Princeton, New Jersey. STEADMAN, D. W., and H. B. FREIFELD. 1998. REMSEN, J. V., JR., and S. K. ROBINSON. Distribution, relative abundance, and 1990. A classification scheme for foraging habitat relationships of landbirds in the behavior of birds in terrestrial habitats. Vava'u Group, Kingdom of Tonga. Con Pages 144-160 in M. L. Morrison, C. J. dor 100: 609-628. Ralph, J. Verner, and J. R. Jehl Jr., eds. STEADMAN, D. W., D. S. PAHLAVAN, and P. Avian foraging: Theory, methodology, V. KIRCH. 1990. Extinction, biogeogra and applications. Stud. Avian BioI. 13. phy, and human exploitation of birds on RIPLEY, S. D. 1964. Subfamily Turdinae, Tikopia and Anuta, Polynesian outliers in Thrushes. Pages 13-227 in E. Mayr and the Solomon Islands. Bishop Mus. Occas. R. A. Paynter Jr., eds. Check-list of birds Pap. 30: 118-153. of the world, Vol. X. Museum of Com STEADMAN, D. W., J. P. WHITE, and J. parative Zoology, Cambridge, Massachu ALLEN. 1999. Prehistoric birds on New setts. Ireland, Papua New Guinea: Extinctions --. 1977. Rails of the world. David R. on a large Melanesian island. Proc. Natl. Godine, Boston. Acad. Sci. U.S.A. 96: 2563-2568. ROHWER, S. 1989. Foraging differences be WOLFF, T. 1973. Notes on birds from Rennell tween white and dark morphs of the and Bellona Islands. Nat. Hist. Rennell Pacific Reef Heron Egretta sacra. Ibis lsI., Br. Solomon lsI. 7: 7-28. 132: 21-26.