摘要:

SUMMARYZann, R. A. 1976. Variation in the songs of three species of estrildine grassfinches. Emu 76: 97–108.One hundred and ninety-sir song phrases made by forty-two individuals were analysed sonagraphically. The birds belonged to the formsPoephila p. personataandleucotis, P. c. cinciaandatropygialis, P. a. acuticaudaandhecki.The songs of grassfinches are very soft and audible only at close range. They do not have an advertising function but are used during courtship just before copulation; there is also an Undirected Song. All three species show Variation in structure of the song of the same type and some to the same degree as that of most passerines. There is variation between species, subspecies, geographical populations and individuals. The advantage of having variation in close contact signals such as grassfinch songs remains unknown. There are evolutionary trends inPoephilato modify the structure of the song by increasing its structural segmentation, the stereotypy and duration of its phrases and elements, its loudness and musicality. These features have their weakest expression inP. bichenoviiandP. guttataand their highest inP. acuticauda.

ISSN:0158-4197    

DOI:10.1071/MU9760097

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYSCHODDE, R., and I. J. MASON. 1975. A new subspecies ofColluricincla megarhynchaQuoy and Gaimard from the Northern Territory, Emu: 109–114.Colluricincla megarhyncha(brownish-grey-billed group) is recorded for the first time for the Northern Territory, from mangroves at the mouths of the McArthur and probably Roper Rivers. The local form is described as a new subspecies;C.m. aelptes;characterized by a pallid undersurface, rather heavily streaked breast, pale-buff eye-brow and long bill.Aelptesis intermediate in morphology and geographical position between eastern Australian forms ofmegarhynchaandColluricincla parvulafrom north-western Australia, implying thatparvulaandmegarhynchaare conspecific.

ISSN:0158-4197    

DOI:10.1071/MU9760109

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYHarrison, C. J. O. 1976. Some aspects of adaption and evolution in Australian fan-tailed flycatchers. Emu 76: 115–119.In the genusRhipidura, the typical fan-tailed flycatchers such as the Grey FantailR. fuliginosaare arboreal and the erected and fanned tail appears to be used for scaring insects into flight so that they can be captured. The Willie WagtailR. leucophrysshows terrestrial adaptations. Vertical tail-fanning is replaced by wing-flashing and some characters of plumage-pattern, voice and nesting may be related to the more open habitat used by the species. Osteologically its leg-bones are longer and its pelvis slightly longer and narrower, which may be correlated with its terrestrial habits. The Northern FantailR. rufiventrisis a more sluggish arboreal species, capturing insects in short flights from a perch and lacking the tail-erecting behaviour. Its leg-bones are short relative to those of the Grey Fantail, but similar in proportion to those of some monarchine flycatchers, and this may be correlated with more sedentary behaviour. These behavioural differences linked with morphological divergence may justify the re-use, as subgeneric or generic divisions, of the namesLeucocircafor the Willie Wagtail andSetosurafor the Northern Fantail and related species. The Willie Wagtail probably evolved in Australia in a refuge area with a more open habitat but the Northern Fantail probably evolved in forests of the New Guinean region.

ISSN:0158-4197    

DOI:10.1071/MU9760115

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYForshaw, J. M., P. J. Fullagar and J. I. HARRIS.1976. Specimens of the Night Parrot in museums throughout the world. Emu 76: 120–126.Available information from the twenty-two known specimens of the Night ParrotGeopsittacus occidemalis, Gould, is presented. Comments are made on the ornithological or historical importance of some specimens and particular attention is given to the specimen collected by John McDouall Stuart in 1845 and now housed in the Merseyside County Museums, Liverpool, England. The success of F. W. Andrews, taxidermist and collector with the South Australian Museum, in obtaining specimens of the Night Parrot is emphasized.

ISSN:0158-4197    

DOI:10.1071/MU9760120

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYBraithwaite, L. W. 1976. Notes on the breeding of the Freckled Duck in the Lachlan River Valley. Emu 76: 127–132. Details are given for four breeding records of the Freckled DuckStictonetta naevosa.Aspects of the habitats that seem important for breeding are noted. For three records, nests are described and clutch-size and measurements of eggs are given. An incubation period of thirty-six days is given for one clutch. Notes on behaviour are also presented. There was no evidence of a pair-bond between incubating birds and other Freckled Ducks near the nests.

ISSN:0158-4197    

DOI:10.1071/MU9760127

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYDISNEY. H. J. de S., and A. STOKES. 1976. Birds in pine and native forests. Emu 76: 133–138.The Monterey PinePinus radiatahas been planted in Australia for about ninety years. In recent years, large amounts of native forest have been removed and planted with pines, which has greatly affected the original fauna. Almost any bird can be expected to forage in a pine plantation of mixed age-classes. This paper reports the birds seen and breeding in sample plots of 8.09 hectares in pine forest, dry sclerophyll and wet sclerophyll. Many more individuals were observed in the wet sclerophyll than in the pines or dry sclerophyll and the diversity of species was also much greater. Dry schlerophyll was slightly more diverse than the pines. The breeding diversity was two or three times greater in the native forest than in the pines. Of Australian landbirds 19.7 per cent usually or always nest in holes or on stumps. In native forest 35–40 per cent of the birds may use holes but only 11 per cent do so in the pines. Most trees in the native forest did not have suitable holes for breeding birds until they were 500 millimetres in diameter or at least fifty years old.

ISSN:0158-4197    

DOI:10.1071/MU9760133

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYMaclean, G. L. 1976. Rainfall and avian breeding seasons in north-western New South Wales in spring and summer 1974–75. Emu 76: 139–140.As a result of unusually heavy rains since 1973, many bird species in north-western New South Wales became seasonal breeders, starting to nest in the spring of 1974. Opportunistic breeding was no longer released by rainfall, probably because of some physiological or ecological feedback mechanism or both resulting from prolonged breeding since the start of the wet period (e.g. gonadal exhaustion, high population densities). This reflects an ancestral capacity in arid-zone birds to respond to environmental cues of a purely seasonal nature (photoperiod, temperature) rather than to the usual arid-zone cues of rainfall and the resulting improvements in food supply and vegetation.

ISSN:0158-4197    

DOI:10.1071/MU9760139

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

摘要:

SUMMARYHulsman, K. 1976. The robbing behaviour of terns and gulls. Emu 76: 143–149.The robbing behaviour of some larids at One Tree Island, Great Barrier Reef, was observed. Terns usually were moderately successful when robbing members of their own species but stole only a few fish brought into a colony. Between species, Roseate Terns rarely succeeded though they often tried to rob Black-naped Terns whereas Silver Gulls frequently succeeded and often tried to rob Lesser Crested and Crested Terns. The number of attempts by most species was greatest during high tide when the most pirates were round the colonies. The success of Silver Gulls varied in time and place. Some of the variables that affected the success were the number of Gulls attacking a tern, the length of the fish, the size of the pirate relative to its victim and the strategy used.

ISSN:0158-4197    

DOI:10.1071/MU9760143

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

ISSN:0158-4197    

DOI:10.1071/MU9760150

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor

ISSN:0158-4197    

DOI:10.1071/MU9760151

出版商:Taylor&Francis    

年代:1976

数据来源: Taylor