摘要:

SummaryRecher, H.F., Davis, W.E. Jr.,&Holmes, R.T. (1987). Ecology of Brown and Striated Thornbills in forests of south-eastern New South Wales, with comments on forest managementEmu87, 1–13.Brown and Striated ThornbillsAcanthiza pusillaandA. lineataare abundant and widespread in forests of south-eastern Australia. The two species are similar in appearence and often occur together. However, the Striated Thornbill forages mainly in the subcanopy and canopy (>75% of foraging observations) where it specialises in taking food from the foliage of eucalypts (>90% of observations). The Brown Thornbill forages mainly in the shrub layer (>70% of observations) and takes prey from bark, debris and the leaves of a large variety of plants including eucalypts. Both thornbills forage mainly by gleaning but the Striated Thornbill commonly hang-gleans (>20% of observations), a behaviour rarely used by Brown Thornbills (<5% of observation). Because of their ecological differences, the two thornbills respond differently to forest management. Striated Thornbills are disadvantaged by logging, which reduces the amount of canopy and subcanopy vegetation, but Brown Thornbills benefit from the increased amount of shrub and ground vegetation that results. Conversely, Brown Thornbills are adversely affected by fires that reduce the amount of debris and low vegetation. In the absence of eucalypts, Striated Thornbills are absent from pine (Pinus) plantations, but Brown Thornbills may be abundant. The abundance of thornbills, their wide distribution and different responses to forest management suggests that they could be useful in monitoring the health of forest ecosystems and for developing plans of management that take into account the differing requirements of forest wildlife.

ISSN:0158-4197    

DOI:10.1071/MU9870001

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

SummaryWhite, F.W.G. (1987). Macrogeographic variation of the song of the Olive Whistler in Australia.Emu87, 14–25.The macrogeographic variation of the territorial advertisement song of the Olive WhistlerPachycephala olivaceaover its range in Australia is described. The existence of this variation between isolated and widely separated populations, and dialect changes in contiguous population groups, demonstrate song learning in this species. In the four isolated populations in the north, with no mutual social contacts, the vocal patterns result from the use of arbitrarily adopted forms of notes or syllables. In the larger population regions, where intermittant social contact occurs, nine dialect regions are identified by the notes and syllables that begin and end the song. The very large changes in the pattern occurring at the western extremity of the range are not explained, but may be due to unidentified environmental factors.

ISSN:0158-4197    

DOI:10.1071/MU9870014

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

SummaryRinke, D. (1987). The avifauna of 'Eua and its off-shore islet Kalau, Kingdom of Tonga.Emu87, 26–34.This paper reports observations on the birds of the Tongan island of 'Eua and its small off-shore island Kalau, which has never been visited by ornithologists. Thirty-two species have been observed, and notes on the biology of most of these are given. Three species have become extinct on 'Eua since the end of the 18th century, one of which,Clytorhynchus vitiensis, was seen on Kalau. The composition of the avifauna, the avifaunal changes since human settlement, and current threats to the birds of 'Eua are briefly discussed.

ISSN:0158-4197    

DOI:10.1071/MU9870026

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

SummaryOlsen, P.D.&Olsen, J. (1987). Movements and measurements of the Australian KestrelFalco cenchroides.Emu87, 35–41.Australian Kestrels are resident, partially migratory, dispersive and nomadic. Evidence was found of regular seasonal movements northward, especially, and coastally for the winter, out of the deserts for the summer, and down from higher altitudes in the south-eastern Australia for the winter. Australian Kestrels are irregular vagrants to many areas when conditions are favourable, regardless of season. Some differences in seasonal movements between age groups and sexes were found. Body weight was greatest in autumn. Slight geographic variation was found in body measurements. Wingspan, and perhaps tarsal breadth, provide the best means of separating the sexes using measurements. First year birds and adults can probably be separated in the hand, but not consistently in the field, using plumage differences.

ISSN:0158-4197    

DOI:10.1071/MU9870035

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

摘要:

SummaryBrickhill, J. (1986). Breeding success of MalleefowlLeipoa ocellatain central N.S.W.Emu87, 42–45.Nests of Malleefowl were located during the nest building stage in August and September in three successive years (1981–1983). Nests were excavated at fortnightly intervals from just after the start of egg laying (in mid-October) until they were abandoned (in Feb.-Apr.), to determine the number and fate of eggs laid. A total of 530 eggs was studied in 34 nests; the mean clutch size was 15.6, range 3–33 with interquartile range 11–19 eggs. Of all eggs laid, 46.4% resulted in chicks that left the nest. In the last two years of the study there was a drought year followed by an exceptionally wet year. The extremes in rainfall were reflected in the number of eggs laid and their fate. Possible reasons for this are discussed.

ISSN:0158-4197    

DOI:10.1071/MU9870042

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

ISSN:0158-4197    

DOI:10.1071/MU9870046

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

ISSN:0158-4197    

DOI:10.1071/MU9870050

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

ISSN:0158-4197    

DOI:10.1071/MU9870053

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

ISSN:0158-4197    

DOI:10.1071/MU9870057

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor

ISSN:0158-4197    

DOI:10.1071/MU9870059

出版商:Taylor&Francis    

年代:1987

数据来源: Taylor