A study of breeding in grey kangaroos, Macropus giganteus Shaw and M. fuliginosus (Desmarest), in central New South Wales

1973 ◽  
Vol 21 (2) ◽  
pp. 183 ◽  
Author(s):  
WE Poole
Keyword(s):  
Mortality Rate ◽  
New South ◽  
Sympatric Species ◽  
Significant Excess ◽  
South Wales ◽  
Grey Kangaroo ◽  
Group A ◽  
Age Range ◽  
Sexually Mature ◽  
Old Females

A total of 2750 grey kangaroos were examined at Mt. Hope, N.S.W., over a period of 4 years, commencing in 1962. Two colour phases of grey kangaroo were recognized but it was not until late in the study that concurrent investigations revealed that two sympatric species occurred in the area in the approximate ratio 1 : 8. As it was not possible to distinguish the species accurately in retrospect, all the kangaroos were treated as one group. A few males became sexually mature at 20 months of age, most by 36 months, and all before they were 72 months old. Females generally became sexually mature when between 20 and 36 months of age but onset of breeding was dependent on the breeding season (September-March). Most females were breeding by their second summer, some by the third summer, and a few not until the fourth summer. Most births occurred between September and March but some occurred in all months of the year. Of the total females carrying pouch young, 5% had dormant embryos in the uterus and all of these had pouch young more than 180 days old. The highest per- centage of females carrying dormant embryos was found in late autumn, possibly because of improved nutrition after heavy rains. No western grey kangaroos apparently carried a dormant embryo but 30% of the total eastern grey females did. A significant excess of pouch young were attached to an anterior rather than a posterior teat in multiparous females. When an anterior teat was already being suckled by a young-at-foot, the posterior teat on the same side was apparently shielded and a significant excess of young born to such females attached to the anterior teat on the non-suckled side. If a posterior teat was enlarged, almost two-thirds of the newborn young attached to anterior teats; the greater number on the non-suckled side. One female had two young in the pouch, separated in age by the length of one gestation period, indicating that suckling by the first young had failed to inhibit the next expected ovulation. Disparity between 713 male and female young was not significant at 105: 100 for pouch young and 84: 100 for young-at-foot. For sets of pouch young through the age range 113-280 days there was an estimated constant mortality rate of 1.82% per 28 days. No between-sex or between season variation in the mortality rate was revealed.

Reproductive synchrony of three sympatric species of wobbegong shark (genus Orectolobus) in New South Wales, Australia: reproductive parameter estimates necessary for population modelling

2007 ◽  
Vol 58 (8) ◽  
pp. 765 ◽  
Author(s):  
Charlie Huveneers ◽  
Terence I. Walker ◽  
Nicholas M. Otway ◽  
Robert G. Harcourt
Keyword(s):  
New South ◽  
New South Wales ◽  
Species Conservation ◽  
Sympatric Species ◽  
Parameter Estimates ◽  
Reproductive Parameters ◽  
Population Modelling ◽  
Male Population ◽  
Total Length ◽  
South Wales

Reproductive parameters of three closely-related sympatric species of wobbegong (Orectolobus ornatus, O. maculatus and O. halei) off New South Wales (NSW) were investigated to contribute to a biological basis for the management of a commercial fishery targeting wobbegongs. Estimates of the onset of maturity based on ovary condition were 729 mm, 1117 mm, and 1591 mm total length (TL) for O. ornatus, O. maculatus and O. halei respectively. The length at which 50% of the male population is mature based on clasper calcification was 803 mm, 1282 mm and 1784 mm TL for O. ornatus, O. maculatus and O. halei, respectively, and was similar to female onset of maturity based on uterus condition and to TL-at-maternity. These species of wobbegong had synchronous, triennial reproductive cycles. Follicles took 2 years to enlarge before ovulation. During the first year, follicles remained small, and then grew rapidly during the second year before ovulation during November. Gestation lasted ~10–11 months and parturition occurred during September–October. Mean litter sizes were nine (s.e. 0.5) and 21 (s.e. 1.5) for O. ornatus and O. maculatus, respectively, and increased with female total length in O. ornatus. Pregnant O. ornatus and O. maculatus were frequently caught in northern NSW and no pregnant wobbegongs, or females with large, yolky follicles were captured south of Sydney. Differences in the reproductive conditions of wobbegongs caught in northern and central NSW suggested geographically dependent reproductive behaviour. Knowledge of the reproductive parameters provided in this paper is necessary for adequate fisheries management and species conservation assessments.

Habitat Use by Sminthopsis-Crassicaudata, Planigale-Gilesi and Planigale-Tenuirostris (Marsupialia, Dasyuridae) in Semiarid New-South-Wales

1987 ◽  
Vol 14 (4) ◽  
pp. 385 ◽  
Author(s):  
DG Read
Keyword(s):  
Regression Analysis ◽  
Habitat Use ◽  
Arid Zone ◽  
New South ◽  
New South Wales ◽  
Sympatric Species ◽  
Sminthopsis Crassicaudata ◽  
South Wales ◽  
Soil Cracks ◽  
Habitat Variables

Habitat use by Sminthopsis crassicaudata, Planigale gilesi and P. tenuirostris was investigated in the arid zone of New South Wales. All species showed considerable flexibility in habitat use at all times, and abundance was poorly predicted from easily measured parameters of the habitat. However, evidence was found for separation of microhabitat among these sympatric species. Multiple regression analysis indicated that abundance of S. crassicaudata was negatively associated with height of vegetation and the depth and density of soil cracks, and that of P. gilesi was positively associated with these habitat variables. Plant height was positively associated with abundance of P. tenuirostris and it was the only important predictor for this species. These results are discussed in conjunction with trapping records from other habitats.

Reproductive cycles, fat body cycles and socio-sexual behaviour in the Mallee dragon, Amphibolurus fordi (Lacertilia : Agamidae)

1978 ◽  
Vol 26 (4) ◽  
pp. 653 ◽  
Author(s):  
HG Cogger
Keyword(s):  
Life Cycle ◽  
Sex Ratio ◽  
Fat Body ◽  
New South ◽  
Reproductive Period ◽  
South Wales ◽  
Behavioural Types ◽  
Fat Bodies ◽  
Reproductive Cycles ◽  
Sexually Mature

A field study of the reproductive and fat cycles of the small agamid lizard Amphibolurus fordi was undertaken in two areas of mallee in central western New South Wales. The development of the gonads, including the histology of the testicular cycle, is described, together with correlated changes in the size of the inguinal fat bodies. The males emerge from winter torpor some 4-5 weeks before the females. The sex ratio approximates unity throughout the life cycle. Mating occurs from October to December; up to three clutches each of two or three eggs are laid in a season. The eggs hatch in 7-9 weeks after laying. The construction of the nesting chamber by the female is described. Apart from behaviour specifically geared to thermoregulation, two other behavioural types have been identified: male-female interactions involving only sexually mature individuals during the reproductive period, and non-sex-specific patterns which occur in both immature and mature individuals of either sex. Males are not territorial.

The Diet of the Eastern Grey Kangaroo and Wallaroo in Areas of Improved and Native Pasture in the New England Tablelands.

1983 ◽  
Vol 10 (2) ◽  
pp. 203 ◽  
Author(s):  
RJ Taylor
Keyword(s):  
New England ◽  
New South ◽  
New South Wales ◽  
Plant Parts ◽  
South Wales ◽  
Grey Kangaroo ◽  
Native Pasture ◽  
Tussock Grasses

The diet of the eastern grey kangaroo and wallaroo was compared at 2 sites, Lana and Newsholme, in the New England tablelands of New South Wales. At Lana, the pastures had been fertilized for 20 yr and were dominated by low-fibre grasses such as Bothriochloa, Eragrostis, Sporobolus, Microlaena, Danthonia and Vulpia; some paddocks had been sown with introduced grasses, Phalaris, Festuca and lucerne. Coarse tussock grasses such as Poa spp., Stipa and Danthonia pallida predominated at Newsholme. The major difference in the diet of the 2 spp. was in winter when individuals on the unimproved area at Newsholme ate a higher proportion of tussock grasses and less low-fibre grass. Both spp. consistently selected for low-fibre grass leaf; they did not differ in their use of plant parts. The diets contained many plant spp. in common, although there were major differences in the use of several spp. The plant spp. favoured only by the wallaroo were of a higher quality than those favoured only by the grew kangaroo.

Seasonal variation in reproductive performance of Merino ewes in northern New South Wales

1962 ◽  
Vol 2 (4) ◽  
pp. 69 ◽  
Author(s):  
JF Barrett ◽  
TF Reardon ◽  
LJ Lambourne
Keyword(s):  
Seasonal Variation ◽  
Birth Weight ◽  
Reproductive Performance ◽  
New South ◽  
New South Wales ◽  
Early Summer ◽  
The Other ◽  
South Wales ◽  
Group A

Two groups of Merino ewes were observed for five years to determine the variation within years and to make comparisons between years in the numbers of ewes exhibiting oestrus, in fertility, and in lamb birth weights. A group of 35 ewes (continuous), was run constantly with vasectomized rams and services were recorded. From the other (changing) group, a fresh sub-group of 15 ewes was joined with fertile rams every four to six weeks; services were recorded, together with lambing performance and lamb birth weights.Distinct breeding and anoestrous seasons similar to those shown by other workers were observed in both groups of ewes. However, the onset of oestrous activity was a month earlier in the changing ewes than in the continuous ewes.Fertility was low during spring and early summer and reached a maximum in autumn.The birth weight of the lambs appeared to be predominantly influenced by the ewes' nutrition during pregnancy.

The winter mortality of eggs of Chortoicetes terminifera (Walk.) (Orthoptera: Acrididae) during the outbreak of 1955.

1965 ◽  
Vol 13 (1) ◽  
pp. 47 ◽  
Author(s):  
TW Hogan
Keyword(s):  
Mortality Rate ◽  
New South ◽  
New South Wales ◽  
South Australia ◽  
Winter Mortality ◽  
Winter Rainfall ◽  
Median Percentage ◽  
Factors Affecting ◽  
South Wales ◽  
North Eastern

Migratory swarms of Chortoicetes terminifera established egg beds in New South Wales, South Australia, and Victoria during the autumn of 1955. Samples of eggs were taken from a number of districts in New South Wales and Victoria during the winter and the mortality rate was determined. Scelio fulgidus was the only parasite present but it was very widespread with a median percentage parasitization of 5%. Mortality from other causes had a median of 39%. Winter rainfall during 1955 was considerably above average and in some situations waterlogging of the soil in which the eggs were laid may have been one of the factors affecting survival. Low temperature seems more likely to have been the factor of importance at the higher altitudes in north-eastern Victoria where hatching was particularly poor.

Movements and Home Ranges of Three Sympatric Dasyruids, Sminthopsis crassicaudata, Planigale gilesi and P. tenuirostris (Marsupialaia), in Semiarid Western New South Wales

1984 ◽  
Vol 11 (2) ◽  
pp. 223 ◽  
Author(s):  
DG Read
Keyword(s):  
New South ◽  
New South Wales ◽  
Sympatric Species ◽  
Trapping Site ◽  
Niche Separation ◽  
Home Ranges ◽  
Sminthopsis Crassicaudata ◽  
South Wales ◽  
Local Abundance

A mark and recapture study was conducted over 2 years in a trapping site ofapproximately 50 ha. Ofthe 692 individuals captured, 30% were recaptured; in all trapping periods, a high proportion of animals caught had not been captured previously. The three species showed considerable mobility throughout the year, but during June Planigale spp. were more sedentary. Mobility is implicated in the changes in local abundance of these insectivores. Some individuals had movements in excess of 400 m day-l; average rates of displacement were 620 m in 100 days for Sminthopsis crassicaudata and 400 m in 100 days for Planigale gilesi. Home ranges ofall species were described as unstable and continually shifting. It is suggested that mobility is an important factor in niche separation between these sympatric species.

A novel observation of dingoes (Canis lupus dingo) attacking a swimming eastern grey kangaroo (Macropus giganteus)

2010 ◽  
Vol 32 (2) ◽  
pp. 201 ◽  
Author(s):  
Brad V. Purcell
Keyword(s):  
Shallow Water ◽  
Deep Water ◽  
Canis Lupus ◽  
Functional Role ◽  
New South ◽  
Keystone Species ◽  
Hunting Strategies ◽  
South Wales ◽  
Grey Kangaroo

The dingo (Canis lupus dingo) is a keystone species in Australian ecosystems. The current study reports four dingoes observed attacking a swimming eastern grey kangaroo (Macropus giganteus) in the Wollondilly River, New South Wales. It is proposed that kangaroos need to stand at a certain depth of water to escape an attack by dingoes. If dingoes can continue attacking from opposing directions without threat of injury from the kangaroo, such as in shallow water where dingoes can stand or deep water where kangaroos cannot stand, then the attack may continue until the predator(s) kill the prey or the prey escapes. Further research on such behaviours is needed to understand the functional role of dingoes and the importance of pack structure in development of hunting strategies.

Demographic characteristics of mallee pine (Callitris verrucosa) in fire-prone mallee communities of central New South Wales

2002 ◽  
Vol 50 (5) ◽  
pp. 653 ◽  
Author(s):  
R. A. Bradstock ◽  
J. S. Cohn
Keyword(s):  
New South ◽  
New South Wales ◽  
Plant Age ◽  
Age Classes ◽  
Site Factors ◽  
Feedback Effects ◽  
South Wales ◽  
Seed Crops ◽  
In Fire ◽  
Age Range

Aspects of the demography of Callitris preissii subsp. verrucosa (Cunn. ex. Endl.) J.Garden populations were studied in semi-arid mallee communities situated on sandy soils in central New South Wales. Rates of survival and fecundity were estimated in a range of populations of differing age (year of origin or last fire: 1920, 1957, 1972, 1974 and 1985) that were monitored between 1987 and 1997. Rates of survival of juveniles and adults were high (>0.99 p.a.), although juveniles less than 5 years of age survived at lower rates. Estimated seedbank at the time of first tagging (no. of closed cones per plant) followed an increasing trend with plant age. Density, overstorey, topography and within-age-class site factors had significant effects on stored seedbanks in particular age-classes. There was high interannual variation (1989 v. 1990) in the size of crops of new cones. Trends in seedbank with plant age and seed release rates from tagged cones indicated that the species exhibits strong serotiny. Measurements of litter weight and depth beneath plants from 1920 and 1957 age-classes, indicated relatively low fuel loadings (about 0.2�kg m–2). Bark was sufficiently thick in c. 60-year-old plants to render stems resistant to low-intensity fires. Thus, it is predicted that the probability of propagation of fire in populations >50 years old may decline and that survival of fire in this age range may increase. Given patterns of survivorship, fecundity and seedbank accumulation, populations may decline when fires are relatively frequent (<15-year interval). At longer intervals there is potential for population densities to remain stable or increase, although the nature of variability in sizes of individual seed crops may have a predominant influence on dynamics. The combination of strong serotiny and negative feedback effects of plant populations on their flammability is a paradox, given the likelihood that seedling establishment is tightly keyed to fire.

Sign in / Sign up

Export Citation Format

Share Document