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.

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.

Nematode parasites of free-living rabbits, Oryctolagus cuniculus (L.) in eastern Australia

1966 ◽  
Vol 14 (2) ◽  
pp. 185 ◽  
Author(s):  
JD Dunsmore
Keyword(s):  
Breeding Season ◽  
New South ◽  
New South Wales ◽  
Nematode Parasites ◽  
South Central ◽  
South Wales ◽  
Eastern Australia ◽  
Regular Sampling ◽  
A Site ◽  
North Western

(1) Trichostrongylus retortaeformis (Zeder, 1800) in wild rabbits in Australia has been studied by more or less regular sampling of rabbit populations in four climatically different areas of eastern Australia. (2) In a semi-arid locality in north-western New South Wales, T. retortaeformis is rarely found; in a subtropical area of south-central Queensland it was found only in small numbers and many rabbits were apparently free of infection. In an area of the Riverina district of New South Wales most rabbits were infected but parasite numbers were rarely high. The highest levels of infection were recorded at a site in a subalpine area of New South Wales. (3) It was possible to build up a detailed picture of the dynamics of T. retortaeformis in rabbits throughout their lives at Snowy Plains, the subalpine site, in which breeding of rabbits is limited to a relatively few months each year. During their first 6-8 months of life (prior to their first breeding season) male and female rabbits carry moderate numbers of T. retortaeformis with the males carrying somewhat more parasites than the females. During the breeding season T. retortaeformis numbers in female rabbits increase very markedly (about tenfold) while numbers in male rabbits are decreasing to a low level (their lowest during the year). Following breeding, worm numbers in female rabbits drop quite rapidly while those in males increase to a similarly moderate level. Apparently a similar cycle of events occurs during each 12 months of a rabbit's life. (4) At Urana, in the Riverina plain region the cycle of events described above for Snowy Plains could not be seen, although T. retortaeformis was found in moderate numbers. This may have been due to infrequent sampling, lack of a defined rabbit breeding season, or some other factor.

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.

The distribution and status of the Giant Burrowing Frog Heleioporus australiacus in the Shoalhaven region of south-eastern New South Wales

2019 ◽  
Vol 40 (2) ◽  
pp. 256-271
Author(s):  
Garry Daly
Keyword(s):  
Efficient Method ◽  
New South ◽  
New South Wales ◽  
Late Summer ◽  
Breeding Sites ◽  
Fragmented Populations ◽  
South Wales ◽  
Open Forest ◽  
Drainage Line ◽  
Discrete Populations

Surveys were conducted for the Giant Burrowing Frog Heleioporus australiacus within 50 km of Nowra, on the south coast of New South Wales using a variety of methods. Thirty-eight 250 m transects were surveyed at night for 30 min each and 0–12 adult frogs were detected during these searches. Additional diurnal searches for tadpoles proved to be the most efficient method to detect the species and locate breeding sites. Of 102 sites surveyed, fragmented populations were found at 27 by the presence of tadpoles and adult frogs. The vegetation at these sites was woodland and open forest with a dense shrublayer of heath, but was often ecotonal. Forty-six percent of the sites were within 100 m of cliff edges/waterfalls. The lithology of sites where the frog was found varied from Hawkesbury, Nowra and Snapper Point sandstones. The exception was a population south of Ulladulla that occurs on undifferentiated sediments, but at that site exposed sandstone and a sandy overlay was present. The location of tadpoles indicated that adults were highly selective of the section of drainage line used for breeding. Often these sites consisted of a few small pools in non-perennial creeks. Breeding behaviour was associated with late summer and autumn rain, but in some sites reproduction did not occur annually. Based on distribution and habitat preference, the region has five discrete populations. Urban development has fragmented populations.

scholarly journals Myxomatosis: the introduction of the European rabbit flea Spilopsyllus cuniculi (Dale) into wild rabbit populations in Australia

1971 ◽  
Vol 69 (3) ◽  
pp. 331-346 ◽  
Author(s):  
W. R. Sobey ◽  
Dorothy Conolly
Keyword(s):  
Breeding Season ◽  
New South ◽  
New South Wales ◽  
Release Site ◽  
Myxoma Virus ◽  
European Rabbit ◽  
Wild Rabbit ◽  
South Wales ◽  
Breeding Seasons

SUMMARY1. The European rabbit flea Spilopsyllus cuniculi (Dale) bred successfully in wild rabbits on three properties in New South Wales and, within two breeding seasons, almost every rabbit shot within a quarter of a mile of a release site was infested.2. It was demonstrated that the flea transmitted myxoma virus in the field.3. In areas where more than 75 % of the rabbits shot at the beginning of the breeding season were flea-infested and myxoma virus was present, populations failed to show the expected summer build-up.

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