Feeding Observations at a Fruiting Pipturus

On 30 August 1987 a fruiting Pipturus argentaeus Willd. (Urticaceae), which was attracting several species of birds was watched for approximately one hour from 09:00. The tree was c.10m tall and stood in a small clearing beside a dry stream bed in the Veimauri logging area,c .70km north-west of Port Moresby at c. 200m above sea level.

The birds were feeding on small, green, spherical cone-like structures, 2 – 3mm in diameter, which are the immature compound fruits. These compound fruits are borne at intervals, on thin, angled (zig-zag) stems, produced in the leaf axils. The fruits were hard and dry. The mature fruit of P.argenteus is a white, fleshy false berry but none were seen on this tree.

Eight species were observed feeding in the tree. Two pairs of Orange-breasted Fig-Parrots Cyclopsitta gulielmiteri were present for the whole time. They fed actively, climbing from branch to branch throughout the tree. Females of three birds of paradise, Magnificent Bird of Paradise Cicinnurus magnificus, King Bird of Paradise C.regius and Raggiana Bird of Paradise Paradisaea raggiana, visited the tree for short periods, each feeding in only one part of the tree before moving on. A male Brown Cuckoo-Dove Macropygia amboinensis landed on a low branch of the tree. It took a single fruit before attempting to climb to a smaller branch which could not bear its weight. It fell out of the tree and flew into the surrounding forest. A pair of Plain Honeyeaters Pycnopygius ixoides and a pair of Tawny-breasted Honeyeaters Xanthotis flaviventer made repeated visits, feeding throughout the crown. All these birds appeared to ingest the fruit whole. Two Grey Whistlers Pachycephala simplex also visited the tree but did not feed on the fruit, instead they gleaned items from the leaves. No inter-specific aggression was noted, although at times the were eight individuals of four species in the tree.

Voucher specimen at UPNG for P.argenteus is Hicks & Hicks #2. I would like to thank Paul Katik for identifying the food plant.

First published in Muruk 3(1): 15

Owling at the Pacific Adventist College

Owls, nightjars and frogmouths are not easy birds to see. Most observations tend to be of birds glimpsed in car headlights while travelling at night, when identification is not always possible. Members of the PNGBS are fortunate that Len Tolhurst, a PNGBS committee member, works and lives on the SDA Pacific Adventist College campus, which lies south of the Hubert Murray Highway, near Illimo Farm, about 10km from the outskirts of Port Moresby. The campus is surrounded by a security fence which is well lit at night. The lights attract flying insects which in turn attract the night birds and for a change it is possible to see them well. The demand for some night-time bird-watching was such that two trips were organised to the college, on 11 and 13 August 1987.

 

The plan was to drive around the perimeter track to see what had been attracted to the lights. The first birds seen each evening were a pair of Blue-winged Kookaburras using the security fence as a vantage point from which to hunt. Barn Owls, Papuan Frogmouths and Large-tailed Nightjars were perched in open situations where they were easy to see. Having followed the security fence for some way, we moved into the farmland beyond the campus and were surprised how many Barn owls and Large-tailed Nightjars there were. At least five pairs of the latter were scattered over an area of ploughed land, their eyes reflecting red or green in the spot-light beam. These nightjars allowed a close approach when dazzled by the light and subsequently we have managed to trap three for ringing (banding) by this means. While trapped in the light the full details of their cryptic plumage was seen, although under such conditions it afforded them little protection. In the same area there were at least five Barn Owls but no sign of the rarer owls we had hoped for. Papuan Boobook, Barking Owl and Rufous Owl have all been reported from the college.

Our first visit finished on a note of excitement when a large nightjar was trapped in the spotlight beam. It was observed for about 15 minutes spending most of its time perched but occasionally sallying out after insects. It showed no white in the wing or tail and was identified as a White-throated Nightjar. This is thought to be the first sighting of this species, a migrant to New Guinea from its Australian breeding grounds, in the Port Moresby area. A note on this sighting will be in the next issue of Muruk.

On behalf of all those who enjoyed the night time viewing, I would like to thank Len for his hospitality, chauffeuring us around and more importantly knowing where to go, his wife Val for the welcoming drinks and cakes and Mr Wilkinson, the principal of the college for allowing us to roam over his campus and for the loan of his spotlight which greatly helped our viewing.

Species List:

Great Egret, Rufous Night-Heron, Masked Lapwing, Barn Owl, Papuan Frogmouth, White-throated Nightjar, Large-tailed Nightjar, Blue-winged Kookaburra.

First published in Muruk 3(1): 25

White-throated Nightjar Eurostopodus mystacalis: First record for the Port Moresby Area

On 11 August 1987 several members of the PNGBS were looking for night –birds on the Pacific Adventist campus, c.10km east of Port Moresby at c.70m. At 21:30 a large nightjar was seen perched on a bare branch. It was observed for about 15 minutes with the aid of a powerful spotlight from a distance of about 30m. During this time it made three flights, returning to the same perch each time. It was larger than either of a pair of Large-tailed Nightjars Caprimulgus macrurus which were seen at the same time. It showed no white markings either in the wing nor on the underside of the tail. The undertail coverts and undersides of the tail were quite strongly barred. A bird matching this description was seen in the same place on 3 September 1987. After consulting various reference books (Beehler et al. 1986; Coates 1985; Slater et al. 1986) this bird was identified as a White-throated Nightjar Eurostopodus mystacalis. It was seen by nine observers, none of whom had had any previous experience of the species.

Six species of nightjar have been recorded in New Guinea and its satellite islands (Beehler et al. 1986). Of these, five were rejected for the following reasons: 1) The Large-tailed Nightjar is the common nightjar of the savanna around Port Moresby. In flight it shows distinct white markings in the wing and on the underside of the tail; 2) Two species, Jungle Nightjar C.indicus and Spotted Nightjar E.argus have yet to be recorded in PNG, although both are migrants and could occur. Both show distinct white wing patches and the male Spotted Nightjar has white in the tail. 3) Two all dark nightjars, both endemic to New Guinea, can be rejected by size and habitat. The Mountain Nightjar E.archboldi frequents montane rain forest and has not been recorded below 2000m (Coates 1985). The Papuan Nightjar E.papuensis is found almost exclusively in lowland rainforest. Both are similar in size to Large-tailed Nightjar.

A race of the White-throated Nightjar E.m.mystacalisis a migrant to New Guinea from its breeding grounds in eastern Australia. It has been recorded infrequently in PNG with sightings from Western Province through the highlands to the north coast but this is the first sighting for south-east New Guinea. There has been one previous ‘possible’ record for the Port Moresby area when a Nightjar showing small white wing patches and lacking white in the tail was flushed from the road near Brown River in August 1986 (Field Guides Inc, 1988). I suspect this species has been overlooked in the past and is not just a vagrant to the Port Moresby area.

Beehler, B.M., T.K. Pratt & D.A. Zimmerman. 1986. Birds of New Guinea. Princeton University Press.
Coates, B.J. 1985. The Birds of Papua New Guinea. Vol 1. Dove Publications.
Field Guides Inc. 1988. Field Guides Inc tour of Papua New Guinea 1986. Muruk 3:23-24.
Slater, P., P.Slater & R.Slater. 1986. The Slater Field Guide to Australian Birds. Rigby.

First published in Muruk 3(2): 55-56