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.

The Size and Composition of Groups in the Red Kangaroo, Macropus rufus

1979 ◽  
Vol 6 (3) ◽  
pp. 237 ◽  
Author(s):  
EM Russell
Keyword(s):  
Group Size ◽  
Small Groups ◽  
New South ◽  
New South Wales ◽  
Temporal Stability ◽  
Adult Males ◽  
Red Kangaroo ◽  
South Wales ◽  
Macropus Rufus

Red kangaroos, observed in the field in western New South Wales, were dispersed in small groups which, although aggregated near shelter, food or water, appeared to move independently. The temporal stability of these small groups is not known. Mean group size was 2.6, and more animals were seen in groups of two, three or four than were seen alone. Groups of two were most common, more than half of them containing one female with young-at-foot. Mixed-sex groups with one or several adult males were found.

Seasonal Changes in Diet Preferences of Free-Ranging Red Kangaroos, Euros and Sheep in Western New South Wales.

1977 ◽  
Vol 4 (2) ◽  
pp. 127 ◽  
Author(s):  
BA Ellis ◽  
EM Russell ◽  
TJ Dawson ◽  
CJF Harrop
Keyword(s):  
Animal Species ◽  
New South ◽  
New South Wales ◽  
Stomach Contents ◽  
Ovis Aries ◽  
Severe Drought ◽  
Red Kangaroo ◽  
South Wales ◽  
Selective Eating ◽  
Free Ranging

Stomach contents of free-ranging animals were analysed botanically for low Atriplex shrubland in western New South Wales, Australia, during 1972-74 in good seasons producing abundant growth and diversity of vegetation. Red kangaroo (Megaleia rufa), euro (Macropus robustus) and sheep (Ovis aries) selected grass and forbs when those were readily available. In poorer pasture sheep selected mainly flat-leaved chenopods (saltbush) and kangaroos selected mainly grass with different amounts of flat- or round-leaved chenopods. Euros were the most selective, eating grass even when there was little grass present. Potential overlaps in diet between kangaroos and sheep were greatest in good pasture and least in the poorest conditions. The other groups of plants considered were non-chenopod shrubs and browse. Extent of overlap was not clear, because animals may have eaten different species within the groups of plants. The study period did not include any severe drought, in which overlap in diet and competition between animal species would have been most significant.

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.

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.

Group SIze in the Eastern Grey Kangaroo, Macropus giganteus, and the Wallaroo, Macropus robustus

1982 ◽  
Vol 9 (2) ◽  
pp. 229 ◽  
Author(s):  
RJ Taylor
Keyword(s):  
Group Size ◽  
New South ◽  
New South Wales ◽  
Early Morning ◽  
Frequency Of Occurrence ◽  
South Wales ◽  
Grey Kangaroo ◽  
North Eastern

Data were collected on the occurrence of eastern grey kangaroos and wallaroos in groups on two properties (Lana and Newholme) in north-eastern New South Wales. The density of both species was higher on Lana than on Newholme. The frequency of occurrence of groups of different size was significantly different from that expected if the occurrence was random for both species. For the grey kangaroo on Lana, mean group size was smaller during early morning than during the rest of the day. Mean group size was significantly greater on Lana than on Newholme for both species, and smaller for wallaroos than for grey kangaroos on both properties. For both species, mean group size was significantly correlated with the density of kangaroos in each habitat.

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