摘要:

SummaryGeographical variation in the Western WhipbirdPsophodes nigrogularisis reviewed by routine morphometric procedures. Four subspecies are recognised: nominotypicalnigrogularisin extreme coastal south-western Australia,oberonin the mallee heaths of eastern south-west Australia,lashmarion Kangaroo Island andleucogasterin the Murray Mallee and on Yorke and Eyre Peninsulas, South Australia. Two of the subspecies (oberonandlashmari) are described as new. The presence of two forms (nigrogularisandoberon) in south-west Australia raises questions about their taxonomic status and parallels the occurrence of other pairs of Bassian taxa in that region. Reconstruction of the evolution of such pairs identifies the highlands about the South Australian gulfs as an important refuge and source of speciation for Bassian birds during Quaternary and perhaps later Tertiary times. Implications for conservation are reassessed.

ISSN:0158-4197    

DOI:10.1071/MU9910133

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

SummaryThe Western WhipbirdPsophodes nigrogularisat Two Peoples Bay is the only known surviving population of the subspeciesnigrogularis.The preferred habitat is thicket, a two to three metre high formation of varied floristic composition. Other vegetation associations are used infrequently, although all nests were found in dense heath adjacent to areas of thicket. As with other populations, structure, not floristic composition, was the important factor in habitat selection. In the absence of fire, the population has steadily increased since the mid–1960s and in 1982, was of the order of 100 pairs. Western Whipbirds occupy overlapping home ranges of 10–19 ha with core areas ranging from 1.5–2.4 ha. Pair bonds are long-lasting and the pair maintains its home range from year to year. Each sex has its own distinctive song type and the female frequently joins the male to sing a duet. Clutch size was two and all clutches were started between late July and early September. Incubation lasts 21 days and the nestlings fledge when about 12 days old and stay with their parents for about two months. Some juveniles undergo a post-fledging moult to assume adult plumage. Future conservation of the species is dependent primarily on appropriate management of fire.

ISSN:0158-4197    

DOI:10.1071/MU9910145

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

SummaryThe ability of juvenile and adult Black NoddiesAnous minutusto differentiate between related individuals was assessed by examining: (1) the feeding response of adults towards unfamiliar chicks, substituted in place of their own offspring; and (2) the relative behaviour of both adults and young when confronted with unfamiliar individuals. Results show that parent-chick discrimination in the Black Noddy can be detected some time in the fourth week post-hatching and is not correlated with chick movement from the nest. The recognition of both adults and nesting site was detected in the behavioural response of chicks over 28±2 days old. No equivalent discriminatory ability was observed in adults towards their own young at this age. Some discrimination by adults was observed if similarly aged chicks had prematurely fallen from the nest. This relative lack of adult discrimination and the intense nest site recognition by young may result from both pre- and most post-fledging care occurring at the nest. It is hypothesised that the discrimination by young, which occurs without corresponding adult recognition some 12–15 days before fledging, may be related to the period at which both adults are required to forage simultaneously. Once this occurs young begin to defend the nest site and need to distinguish between returning parents and potential intruders.

ISSN:0158-4197    

DOI:10.1071/MU9910158

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

SummaryData on anti-predator and anti-competitor behaviour in the Bell MinerManorina melanophryswere collected opportunistically during two breeding seasons at Healesville, south-eastern Victoria, and show that: (a) nest predators were mobbed by more Bell Miners than were competitors; (b) in general, nest predators were mobbed by more birds within a dense than within a less dense colony; (c) this difference in the mobbing response between colonies does not appear to lead to an increase in reproductive success in dense colonies; (d) intruders were mobbed by more birds early than late in the season; and (e) potential nest predators were mobbed by slightly more Bell Miners than were competitors when an active nest was close by. Mobbing behaviour in the Bell Miner may decrease the risks to individuals engaged in anti-predator defence and helpers' involvement in mobbing may benefit breeders through the‘dilution’of those risks.

ISSN:0158-4197    

DOI:10.1071/MU9910164

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

SummaryWandering AlbatrossDiomedea exulansacoustic signals were studied on the Crozet Archipelago (Southern Indian Ocean). The first description of nine signals (comprising five vocalisations) with their characteristics is given. The repertoire of acoustic signals found in the Wandering Albatross is compared with that of other species of albatrosses. Sexual differences were apparent in the main vocalisation, the‘Yapping’call, performed between mates. The strong links between visual and acoustic repertoires are discussed and the biological function of acoustic signals is proposed.

ISSN:0158-4197    

DOI:10.1071/MU9910172

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

SummaryThe feeding behaviour and diet of Double-banded PloversCharadrius bicinctuswere studied in Rhyll Inlet and on the Churchill Tidal Flats in Western Port, Victoria, in autumn and winter. The birds preferred feeding in sandy (40%), light eelgrass (33%) and sandy-mud areas (27%). They showed a distinct horizontal distribution when feeding, with 88% on wet substrates above the water's edge and 10% at the water's edge. Two feeding modes were employed: isolated pecks and multiple pecking and probing. Pecks were the primary feeding actions observed during daylight. The alternative feeding mode of bursts of multiple pecks (with occasional probes) was observed close to dusk and inferred from tracks in the mud to be commonly used after dark. The mean duration of feeding periods in intertidal areas was 329.4 minutes per diurnal tidal cycle (s.d.±93.3), although in some circumstances, these periods were supplemented by feeding in non-tidal areas. The mean peck rate of Double-banded Plovers feeding in single-peck mode was 0.41 pecks per second (s.d.±0.17) and, in the multiple-peck mode, 0.22 pecks per second (s.d.±0.04). The most significant prey species from intertidal areas was the Sentinel CrabMacrophthalamus latifrons.The adaptive significance of the feeding behaviour of the birds is discussed in relation to physical constraints on feeding and the behaviour and ecology of their main prey.

ISSN:0158-4197    

DOI:10.1071/MU9910179

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0158-4197    

DOI:10.1071/MU9910185

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0158-4197    

DOI:10.1071/MU9910186

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0158-4197    

DOI:10.1071/MU9910189

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0158-4197    

DOI:10.1071/MU9910190

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor