Population dynamics of the common wallaroo (Macropus robustus erubescens) in arid New South Wales

1992 ◽  
Vol 19 (1) ◽  
pp. 1 ◽  
Author(s):  
TF Clancy ◽  
DB Croft
Keyword(s):  
Population Dynamics ◽  
New South ◽  
New South Wales ◽  
Density Fluctuations ◽  
Rainfall Regime ◽  
Total Density ◽  
Adult Males ◽  
Adult Females ◽  
South Wales ◽  
The Common

The population dynamics of the common wallaroo or euro (Macropus robustus erubescens) were investigated in two adjacent sites in far western New South Wales. Wallaroo densities were generally higher in a site of high relief (South Ridge) than in one of low relief (South Sandstone); however, both sites exhibited large fluctuations in numbers (ranges of 2.23-18.31 per km*2 and 3.48-19.99 per km*2, respectively). The proportion of adult males relative to adult females was significantly higher in South Sandstone (c. 1.1 : 1) than in South Ridge (c. 0.4: 1), indicating a difference in habitat usage by the sexes. At both sites, fluctuations in overall density were best explained by changes in the density of adult females; however, the relative importance of changes in the numbers of other size-sex classes in determining density fluctuations differed between the two sites. Total density was significantly related to the previous rainfall regime in South Ridge but not in South Sandstone. Reproductive condition of females and survivorship of young were related to environmental conditions. Adult mortality ranged from 4.55 to 25.81% per year and adult survivorship was positively correlated with the abundance of grass. Evidence is presented to support the hypothesis that dispersal of subadults is predominantly a male phenomenon.

Distribution and Aspects of the Biology of the Parma Wallaby, Macropus parma, in New South Wales

1977 ◽  
Vol 4 (2) ◽  
pp. 109 ◽  
Author(s):  
GM Maynes
Keyword(s):  
New South ◽  
New South Wales ◽  
Embryonic Diapause ◽  
Body Measurements ◽  
Adult Males ◽  
Limited Data ◽  
Adult Females ◽  
South Wales ◽  
Sclerophyll Forest ◽  
The Mean

M. pauma, which was formerly thought to be extinct in Australia, has been found in the Great Dividing Range of coastal New South Wales between 29D 28' and 32D 23's. The optimum habitat appears to be areas of wet sclerophyll forest with a thick shrubby understorey in association with grassy areas. Although the species may be locally common, its present status is best defined as rare; it has a limited distribution and normally occurs at a low density throughout its range. Limited data indicate that most young are born between February and June. Two of six females examined were probably in embryonic diapause. Females may mature sexually as early as 12 months old, and at a weight of 2.6-2.8 kg. Adult females in Australia were significantly heavier than those in New Zealand (Kawau I.), and larger in seven external body measurements. In contrast, adult males were significantly larger in Australia than Kawau I. in ear length only. The species is mainly nocturnal and the mean group size is 1.34 animals, i.e. it is usually single individuals that are encountered.

The population pattern of Miniopterus schrebersii (Chiroptera) in north-eastern New South Wales

1966 ◽  
Vol 14 (6) ◽  
pp. 1073 ◽  
Author(s):  
PD Dwyer
Keyword(s):  
New South ◽  
New South Wales ◽  
Population Characteristics ◽  
Adult Males ◽  
Age Classes ◽  
Adult Females ◽  
South Wales ◽  
Wide Range ◽  
North Eastern ◽  
Population Pattern

In north-eastern New South Wales Miniopterus schreibersii is found at a wide range of cave and mine roosts as colonies that may include up to several thousands of individuals. Between April 1960 and September 1963 a field study of the biology and population characteristics of this species was carried out. Field criteria permitting aging of individuals were developed. Age classes considered were juveniles (< 9 months), yearlings (9-21 months), and adults (> 21 months). Seasonal changes in numbers, and in the sex and age composition of colonies were followed in detail at several roosts and comparative information was obtained at others. Movement patterns were assessed by a marking and recapture programme in which 1365 recoveries were obtained from a marked (toe clips and bands) population of 8775. Conspicuous sex or age biases or both were shown to exist in clusters of M. schreibersii at specific roosts and it was suggested that clustering in this species functions, in part, as a social spacing mechanism. Segregation of different sex or age classes at specific colonies permitted classification of colonies as (1) maternity colonies in which adult females and their young predominate, (2) "adult" colonies which are predominantly adult, or adult and yearling, in composition, and (3) "juvenile" colonies in which juveniles, or juveniles and yearlings, are almost prevalent. The observed social biases of colonies appeared to be related to particular phases of the reproductive cycle. Certain adult colonies were interpreted as important sites of copulatory behaviour. Recovery data for two of these mating colonies showed that adult females were more transient members of the colony than adult males. Juveniles are often well represented at adult colonies in the autumn, and during this season their presence may be correlated with a drop in the abundance of older males.

scholarly journals X. Observations upon the marine barometer, made during the examination of the coasts of New Holland and New South Wales, in the years 1801, 1802, and 1803

1806 ◽  
Vol 96 ◽  
pp. 239-266
Keyword(s):  
Complete System ◽  
New South ◽  
New South Wales ◽  
Common Stock ◽  
Reasonable Expectation ◽  
South Wales ◽  
The Common ◽  
Extended View

A fore-knowledge of the wind and weather is an object so very interesting to all classes of men, and the changes in the mercurial barometer affording the means which appear most conducive to it, a system that should with certainty explain the connection between the variations of the mercury and those in the atmosphere under all circumstances, becomes greatly desirable; to seamen, more especially, whose safety and success depend so much upon being duly prepared for changes of wind, and the approaching storm, it would be an acquisition of the first importance: in a more extended view, I may say, that the patriot and the philanthropist must join with the philosopher and the mariner in desiring its comple­tion. So long and widely-extended a course of observation, however, seems requisite to form even a basis for it, that a complete system is rather the object of anxious hope than of reasonable expectation. Much has been done towards it, but so much appears to remain, that any addition to the common stock, however small, or though devoid of philosophical accuracy, I have thought would be received by the learned with candour. With this prepossession, I venture to submit to them some observations upon the movement and state of the mercury upon the coasts of New Holland and New South Wales, the Terra Australis, or Australia, of the earlier charts.

scholarly journals Lifetime reproductive success in a population of female red kangaroos Macropus rufus in the sheep rangelands of western New South Wales: Environmental effects and population dynamics

2004 ◽  
Vol 26 (1) ◽  
pp. 45 ◽  
Author(s):  
AD Bilton ◽  
DB Croft
Keyword(s):  
Population Dynamics ◽  
Reproductive Success ◽  
Environmental Conditions ◽  
New South ◽  
New South Wales ◽  
Reproductive Potential ◽  
Lifetime Reproductive Success ◽  
South Wales ◽  
Macropus Rufus ◽  
Initial Starting

Female reproductive success and the recruitment of offspring to the next generation are key components of animal population dynamics. With an annual commercial harvest of between 13 and 22% of the red kangaroo (Macropus rufus) population, it is increasingly important that these processes are understood. We used data on the reproductive success of 33 free-ranging female M. rufus on Fowlers Gap station in far western New South Wales to determine the expected lifetime reproductive success (LRS) of females within an unharvested population. We also designed a model to generate predictions about female LRS incorporating empirical relationships between a mother?s reproductive success and maternal age, environmental conditions and the sex and survivorship of a previous reproductive attempt. Results from observations on female LRS (calculated from annual weaning rates) and those generated by the model predict that female M. rufus on ?Fowlers Gap? wean, on average, 3.7 young in a lifetime (ranges 0 - 11 and 0 - 20, respectively); representing only 41% of their maximum reproductive potential. Manipulation of initial starting conditions allowed the effect of varying environmental conditions on female LRS to be explored. The condition of the environment when females commence breeding does not appear to significantly affect their overall lifetime reproductive output. However, the occurrence of drought does. Females experiencing two droughts in a lifetime did not live as long and weaned fewer offspring and grandoffspring (from their daughters) than those females experiencing only one drought in a lifetime. In addition to the adverse effect of drought on the reproductive success of female M. rufus in this study, we suggest that, given the relatively high and stable population densities of M. rufus on ?Fowlers Gap?, other mechanisms (acting primarily on juvenile survival) must exist which limit population growth.

The effects of age, sex, reproductive status and temporal factors on the time-use of free-ranging red kangaroos

1993 ◽  
Vol 20 (6) ◽  
pp. 785 ◽  
Author(s):  
DM Watson ◽  
TJ Dawson
Keyword(s):  
Body Size ◽  
Group Size ◽  
Time Use ◽  
New South ◽  
New South Wales ◽  
Time Of Day ◽  
Adult Males ◽  
South Wales ◽  
Free Ranging ◽  
Foraging Time

The effects of temporal (time of day and season) factors and size, sex, female reproductive state and group size on the diel time-use of free-ranging red kangaroos (Macropus rufus) was examined. Particular emphasis was given to the effects on their foraging behaviour, with foraging divided into cropping, chewing and searching components. The study was conducted in semi-arid western New South Wales from July 1991 to March 1992, a time of deepening drought conditions in New South Wales. Group size had very little influence on the time-use of M. rufus. It was negatively but only weakly correlated with the proportion of foraging time spent chewing (chewing intensity). No significant differences in time-use were found between size classes of adult males (large and medium-sized males), females with or without pouch young, or females with different-sized pouch young (no visible young, small pouch young or large pouch young). Differences occurred between adult males, adult females and subadult kangaroos. These differences were mainly associated with their chewing and searching behaviour and were related to body size; as body size increased the proportion of time spent chewing and the intensity of chewing increased while the proportion of time searching and the proportion of foraging time spent searching (searching intensity) decreased. Neither the proportion of time spent cropping or foraging nor the proportion of foraging time spent cropping (cropping intensity) or the proportion of active time spent foraging (foraging intensity) differed between any size/sex/reproductive class. Temporal effects had a considerable influence on time-use. M. rufus were most active at night and in the few hours after sunrise and sunset. Seasonal changes in time-use were largely a result of changes in daytime behaviour. M. rufus foraged less and rested more during the day in winter than in spring or summer. There was no increase in the intensity or proportion of time spent foraging or cropping at night to compensate for the reduction in diurnal foraging. It is hypothesised that temporal variations in time-use were related to variations in weather and vegetation conditions.

Electrophoretic evidence for the presence of the undescribed ‘Bellinger’ catfish (Tandanus sp.) (Teleostei : Plotosidae) in four New South Wales mid-northern coastal rivers

1997 ◽  
Vol 48 (3) ◽  
pp. 235 ◽  
Author(s):  
Dean R. Jerry ◽  
David J. Woodland
Keyword(s):  
Population Structure ◽  
New South ◽  
New South Wales ◽  
Genetic Data ◽  
Undescribed Species ◽  
Allopatric Populations ◽  
South Wales ◽  
Coastal Rivers ◽  
Allelic Differences ◽  
The Common

Genetic data were collected from eight allopatric populations of the common freshwater catfish, Tandanus tandanus. Catfish sampled from the New South Wales (NSW) mid-northern coastal rivers of the Bellinger, Macleay, Hastings and Manning exhibited fixed allelic differences from T. tandanus from the type locality (Namoi River) at four enzymatic loci (GPI-1*, EST*, UMB-1* and UMB-2*), suggesting that, collectively, catfish from these four river systems constitute an undescribed species of Tandanus. Catfish from the northern coastal rivers of NSW (Tweed, Richmond and Clarence) displayed a complex pattern of population structure that was not fully resolved by the present study. More work is needed on the complex assemblage of populations of eel-tailed catfish in the eastern coastal drainages of Australia.

Movements of Sympatric Red Kangaroos, Macropus-Rufus, and Western Grey Kangaroos, Macropus-Fuliginosus, in Western New-South-Wales

1988 ◽  
Vol 15 (3) ◽  
pp. 339 ◽  
Author(s):  
D Priddel ◽  
G Wellard ◽  
N Shepherd
Keyword(s):  
Population Dynamics ◽  
National Park ◽  
New South ◽  
New South Wales ◽  
South Wales ◽  
Macropus Rufus

Between July 1979 and November 1980 a total of 261 red kangaroos, Macropus rufus, (216F; 45 M) and 170 western grey kangaroos, M. fuliginosus, (136F;34M) were caught and tagged with individually recognisable collars. Between July 1979 and January 1986, 1751 sightings of tagged individuals were recorded. Information gained from these sightings was used to assess how far each kangaroo ranged. More than 90% of individuals of either species did not range far (<9 km for reds; <6 km for western greys) even when local pastures were severely depleted during drought. A few individuals dispersed much further-up to 323 km. On average, red kangaroos ranged further than western greys. Kangaroos on Kinchega National Park ranged no less or no further than those on an adjacent pastoral leasehold. At least 17 tagged individuals crossed the macropod-deterrent fence surrounding Kinchega; several crossed repeatedly. Dispersal of kangaroos from Kinchega was slight, supporting the hypothesis of Bayliss (1985) that dispersal has no significant impact on population dynamics.

Seasonal changes in Pelage of Miniopterus schreibersi blepotis (Chiroptera) in north-eastern NSW.

1963 ◽  
Vol 11 (3) ◽  
pp. 290 ◽  
Author(s):  
PD Dwyer
Keyword(s):  
Seasonal Changes ◽  
New South ◽  
New South Wales ◽  
Age Groups ◽  
Adult Females ◽  
Early Autumn ◽  
South Wales ◽  
North Eastern ◽  
Reproductive Cycles

In M. s. blepotis, of north-eastern New South Wales, the annual moult occurs during the summer and early autumn and lasts about 14.5 weeks. Yearlings having their first moult usually initiate this some 3 weeks after the adults commence. In many adult females the moult is inhibited during lactation and again during the winter so that some individuals may be found moulting in all months of the year. The importance of considering annual pelage characters when using colour taxonomically in bats is emphasized, and possible relationships between moult and reproductive cycles are indicated. In addition the use of pelage characteristics, in conjunction with reproductive criteria as a means of recognizing age groups of M. s. blepotis, is discussed.

Population Parameters of Two Congeneric Possums, Trichosurus spp., in Norh Eastern New South Wales

1981 ◽  
Vol 29 (2) ◽  
pp. 205 ◽  
Author(s):  
RA How
Keyword(s):  
Breeding Season ◽  
New South ◽  
New South Wales ◽  
Adult Males ◽  
Population Parameters ◽  
Bond Population ◽  
South Wales ◽  
Open Forest ◽  
Adult Sex Ratio ◽  
Population Strategy

In adjacent areas in north-eastern New South Wales, T. vulpecula occurs in the open forest and woodland and T. caninus occurs in the closed and tall open forest; both species are found in the pine plantation. T. vulpecula has a single breeding season in autumn when all females 1 y old and older reproduce. The young become independent around 175 days old and disperse at up to 2 y old. Mortality is low (15%) among dependent young but considerably higher among independent dispersing individuals. T. caninus also has a single autumn breeding season. The young become independent around 240 days old but disperse after 18-26 months, females moving before males. Mortality is high (56%) among dependent young but less so among subadults. An adult sex ratio of parity is the result of a higher survival among subadult males than females offsetting the reverse in adults. Some 2-y-old and all 3-y-old females reproduce but a few older females fail to breed in certain years. There is evidence that the high mortality of dependent young and failure of older females to breed is associated with offspring of previous years remaining in the population. Adult males and females appear to form a pair-bond. Population parameters of T. vulpecula described from other areas show considerable variation; this flexibility in population strategy explains the species' success in occupying a diversity of habitats and rapidly colonizing new areas.

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