Fecundity, egg size and the influence of rainfall in an isolated population of malleefowl (Leipoa ocellata)

2005 ◽  
Vol 32 (7) ◽  
pp. 639 ◽  
Author(s):  
David Priddel ◽  
Robert Wheeler

An isolated population of malleefowl (Leipoa ocellata) at Yalgogrin in New South Wales, Australia, was studied intensively between 1986–87 and 1998–99. During this period the population produced 124 clutches, comprising a total of 1705 eggs. The number of clutches per annum varied between 5 and 15. Eggs were laid between mid-August and mid-February, with 90% laid between the last week of September and the first week of January. The mean date of laying of the first egg of each clutch (±s.d.) was 21 September ± 13 days and the mean date of the last egg was 23 December ± 19 days. The mean duration of egg laying varied significantly between years (range 70–117 days) and was negatively correlated with the daily maximum ambient temperature in December. Cool temperatures and rain in early summer prolonged the laying season. The mean interval between laying was 6.4 ± 1.1 days (range 3–12 days), with eggs laid at a faster rate during the first half of the laying period. Overall, mean clutch size was 14.1 ± 5.8 (range 1–28). Large clutches were the result of an extended period of laying rather than an increase in the rate of laying. Mean clutch size was greatest when laying extended into mid-February. The best predictor of clutch size was rainfall between May and December – the interval spanning both nest construction and egg laying. The mean volume of all measured eggs (n = 1362) was 162.1 ± 9.0 mL (range 99–200 mL). Egg volume varied during the laying period, with those eggs laid early or late in the breeding season being smaller. Eggs at Yalgogrin were, on average, 10.5% smaller than those recorded at nearby Pulletop.

2017 ◽  
Vol 25 (5) ◽  
pp. 456-459
Author(s):  
Kevin Rourke ◽  
Coralie J Wilson

Objectives: To determine if adolescents perceive community-based exercise as beneficial to their well-being and in what ways. Methods: A New South Wales Police Citizens Youth Club ran a four-week fitness course. The classes involved: 1) sports including basketball and soccer, 2) non-contact boxing drills, and 3) games, both team games such as dodgeball and non-team games such as line tag. Parental consent to offer a survey at the completion of the course was requested during registration. The survey was the Warwick Edinburgh Mental Well-being Scale; it was minimally modified to measure perceived benefit to mental well-being instead of actual benefit. Results: Thirty-one high school adolescents, ages 13–18, completed the survey. As a group, participants reported that they believed their well-being had improved after the course. The mean score for each survey item showed an improvement in every area of mental well-being for this sample of adolescents. Thirty-two per cent of adolescents reported having less energy. Survey scores indicated a statistically significant improvement in perceived well-being ( p<0.0001). Conclusions: The results of this study suggest that four weeks of community-based exercise improves perceived mental well-being in adolescent participants.


1998 ◽  
Vol 46 (2) ◽  
pp. 153 ◽  
Author(s):  
Damon L. Oliver

The regent honeyea ter, Xanthomyza phrygia, is an endangered woodland bird whose range and population size have decreased in the last thirty years. Suggested reasons for this decline include abnormal breeding behaviour, poor reproductive output, and excessive inter- and intra-specific aggression. This study investigated the breeding behaviour and aggressive interactions of regent honeyeaters during the nest construction, incubation, nestling, and fledgling stages in two consecutive breeding seasons in the Bundarra–Barraba region near Armidale, New South Wales. The female was entirely responsible for nest construction and incubation, which is typical of many honeyeaters. Both parents fed the nestlings, and at a similar rate, although only the female brooded chicks on the nest. Both parents fed the fledglings. The mean frequency at which nestlings (23 times per hour) and fledglings (29 times per hour) were fed is the highest published rate of any non-cooperative honeyeater. Breeding males were involved in significantly more aggressive interactions with conspecifics and other nectarivores than were females, although the overall percentage of day-time spent in aggression for both sexes was low (2.5%). It appears that abnormal breeding behaviour, poor reproductive effort, or excessive aggression are not experienced by this species in northern New South Wales, and that other factors are likely to be responsible for its current low population level.


1994 ◽  
Vol 34 (1) ◽  
pp. 33 ◽  
Author(s):  
GM Lodge

Burrs were collected from paddocks on 3 properties in northern New South Wales where the age of the Trifolium subterraneum var. brachycalycinum cv. Clare swards varied from 19 to 28 years. At 1 site burrs were also sampled from swards sown 2 and 10 years previously. Twenty seedlings from these burrs and 20 plants of certified cv. Clare were grown as spaced plants in a nursery. These were assessed for vegetative and floral characters, flowering time, number of seeds per burr, seed weight, and percentage hardseed after storage at 25/25�C for 6 months and 25/45�C for a further 6 months. For most plants the mean number of days from sowing to first flower was similar to that of Clare. Compared with the naturalised strains, Clare had the lowest (P<0.05) mean number of seeds per burr: about 25% below the mean of the strains (2.7 seeds per burr). While the lowest mean seed weights of the strains were not significantly different from those of Clare, the seed weights of plants from 3 sites were higher (P<0.05) than those of Clare. After storage for either 6 or 12 months, hardseed levels were also lowest (P<0.05) for Clare. Plants from the 2-year-old sward had the same median number of seeds per burr (2.0) as Clare. As sward age increased, the median number of seeds per burr increased to 2.8. Hardseed percentages were lowest for plants of Clare and for those from the 2-year-old sward after 6 months, and for Clare after 12 months. These studies indicated the presence of divergent strains in old swards of Clare in a summer rainfall environment. Natural selection among variability within Clare is the most likely reason for the development of these strains in an environment marginal for the long-term persistence of this softseeded cultivar. Although strains had the same vegetative and floral markings as Clare, differences in ecologically important characters such as number of seeds per burr, seed weight, and hardseededness may result in plants that are better adapted to the environment in which they evolved. From these studies 23 plants of T. subterraneum var. brachycalycinum were selected for further evaluation.


1967 ◽  
Vol 7 (24) ◽  
pp. 7 ◽  
Author(s):  
P McInnes ◽  
TJ Grainger ◽  
MD Smith

Data are presented on the recovery and reproductive performance of 2 1/2-year-old maiden Merino ewes after a prolonged period of undernutrition. The 217 sheep had been hand-fed on a submaintenance ration in pen feeding trials at Glenfield, New South Wales. During the seven months of the trials they had lost 6 kg (28 to 22 kg) body weight. They were transported to Condobolin in south-western New South Wales, divided into two treatment groups and run on good quality pastures. One group was joined immediately (May 1959) and again ten months later, and the other group was mated after six months at Condobolin (in October 1959) and again 12 months later. The ewes recovered rapidly. The mean weight of both groups had reached 30 kg within six weeks and 40 kg within six months. In the first year 73 of the 100 May-mated ewes bore lambs, but only 38 of these lambs were weaned. Ewes bearing lambs had a higher body weight at the start of joining and gained more during joining than the barren ewes. At the other three joinings (October 1959, May 1960, October 1960) lambing percentage was from 86-89 and weaning percentage from 62-69-both normal for the district. The proportion of twin lambs (3-6 per cent) was low. Wool weight in 1959 was not affected by time of mating or by pregnancy.


1968 ◽  
Vol 8 (33) ◽  
pp. 425 ◽  
Author(s):  
EJ Sparke ◽  
DR Lamond

This paper reports an experiment examining the effect of age and protein supplementation on growth and fertility of Shorthorn-Devon cross heifers grazing natural pastures in the summer rainfall, subtropical environment of the Upper Clarence valley, north-eastern New South Wales. Heifers born over the period October to January 1963-64 were weaned in June 1964 and allotted at random within age groups (by month of birth) to a supplemented or non-supplemented treatment. The supplemented heifers were given linseed meal during the dry winter period each year from 1964 to 1966 inclusive (May-June to September-October). They were weighed each month and joined with bulls in the early summer of 1965 (2 years) and 1966 (3 years). They were examined for pregnancy in the autumn, and their calves were identified at birth. Supplemented heifers gained weight throughout and non-supplemented heifers generally lost weight in the winter periods. At two years fertility was closely related to liveweight at joining in supplemented heifers, but not in others. Heifers born in January gave the poorest reproductive performance, as the two supplemented ones that became pregnant in 1965 died at calving, and two-thirds of the non-supplemented ones were still empty after joining as 3-year-olds. The advantage of high 2-year-old fertility gained by heifers born in October and November, due to their greater size at joining, was partly offset by low fertility when lactating the following year. It is concluded that a decision as to whether a heifer should be supplemented during a period of nutritional stress prior to joining ought to be based on the probability of her reaching a prescribed target weight at joining as a result of receiving the supplement. The target weight for lactating heifers was at least 100 Ib higher than for dry hdfers. The results also indicate specific areas for further research.


1985 ◽  
Vol 25 (4) ◽  
pp. 758 ◽  
Author(s):  
DG Hall ◽  
EC Wolfe ◽  
BR Cullis

Pasture production, ewe and lamb growth, ewe wool production and diet quality were studied on lucerne-subterranean clover pastures at Wagga Wagga, New South Wales. Lucerne was sown at rates of 0.75 to 3.0 kg/ha, and the pastures were rotationally grazed with Border Leicester x Merino ewes at 9.6 or 12.7 sheep/ha, the ewes lambing in August- September. Lucerne density declined by 45% over the 3 years on all treatments. The clover cultivar sown, Woogenellup, had low persistence, particularly at 12.7 sheep/ha. The density of lucerne had little effect on annual wool and lamb production, although the ewes grew faster on the denser lucerne in summer and the sparser lucerne in winter. At 12- 7 sheep/ha, there was an extra 19% total lamb weight by the end of November and an extra 22% of finer wool (1 �m) annually, but the fleeces had a higher proportion of wool tenderness. The major limitations of the lucerne-subterranean clover pastures to sheep production were the low quality of the diet in early summer, and low pasture production in late winter. In early summer the lucerne was rapidly consumed, leaving only moderate quality clover and grass residues, which limited lamb growth, while in winter pregnancy toxaemia occurred, fleeces were tender and wool growth was low, particularly during a drought in 1976.


1978 ◽  
Vol 1 (2) ◽  
pp. 167
Author(s):  
VR Squires

In order to assess the current level of stock watering facilities on pastoral properties within the western Riverina district of New South Wales and to relate this information to paddock size and vegetation type, large of areas of land (785,000 ha) within the region were surveyed. Paddock boundaries and the location of watering points were plotted. Watering points were classified as to type. Three broad vegetation types were represented: chenopod shrublands (Atriplex and Maireana spp.) degraded grasslands (Stipal Danthonia spp.), and mallee woodlands (Eucalyptus socinlis F. Meull., E, oleosa, F. Meull.) Size of paddocks was related to the dominant vegetation type. On the degraded grasslands in the eastern part of the study area the mean paddock size was 746 ha; on the chenopod shrublands it was 780 ha, and in the Malleedominated areas it was 1,553 ha. The number of permanent watering points per paddock varied from one to four. Less than half the paddocks (43%) had fresh water available as well as saline waters from sub-artesian bores. Almost half the paddocks (47%) were so large, or the watering points so positioned, that the sheep would need to walk more than 3 km to reach the most remote parts of the paddock when temporary waters had dried up. Overall 18% of the land in the non- mallee areas was more than 3 km from permanent water. Therefore the majority of the land could be used in all seasons. Generally the central and northern Riverina district is adequately watered. It would be uneconomic to supply permanent water in the mallee woodlands. In some paddocks in the chenopod dominated area extra watering points may be justified.


1978 ◽  
Vol 1 (2) ◽  
pp. 106 ◽  
Author(s):  
DL Michalk ◽  
PK Herbert

A study of the density and basal diameter of Chloris acicularis Lindl. (syn. Enteropogon acicularis (LindlJLazar. - curly windmill grass) and C. truncata R. Br. (windmill grass) was made at two stocking rates over a period of eight years. The propor- tion of ground covered by these Chloris species varied widely with season, and to a lesser extent with grazing pressure. The density of both species increased in good seasons, while the mean diameter decreased because of the number of new seedlings. Although C. truncata seedlings were more numerous in good seasons, they did not survive as well as did C. acicularis seedlings during prolonged dry periods.


2020 ◽  
Vol 42 (2) ◽  
pp. 85
Author(s):  
Annemieke Ruttledge ◽  
Ralph D. B. Whalley ◽  
Gregory Falzon ◽  
David Backhouse ◽  
Brian M. Sindel

A large and persistent soil seed bank characterises many important grass weeds, including Nassella trichotoma (Nees) Hack. ex Arechav. (serrated tussock), a major weed in Australia and other countries. In the present study we examined the effects of constant and alternating temperatures in regulating primary and secondary dormancy and the creation and maintenance of its soil seed bank in northern NSW, Australia. One-month-old seeds were stored at 4, 25°C, 40/10°C and 40°C, in a laboratory, and germination tests were conducted every two weeks. Few seeds germinated following storage at 4°C, compared with seeds stored at 25°C, 40/10°C and 40°C. Nylon bags containing freshly harvested seeds were buried among N. trichotoma stands in early summer, and germination tests conducted following exhumation after each season over the next 12 months. Seeds buried over summer and summer plus autumn had higher germination than seeds buried over summer plus autumn plus winter, but germination increased again in the subsequent spring. Seeds stored for zero, three, six and 12 months at laboratory temperatures were placed on a thermogradient plate with 81 temperature combinations, followed by incubation at constant 25°C of un-germinated seeds. Constant high or low temperatures prolonged primary dormancy or induced secondary dormancy whereas alternating temperatures tended to break dormancy. Few temperature combinations resulted in more than 80% germination.


1984 ◽  
Vol 32 (5) ◽  
pp. 631 ◽  
Author(s):  
RJ Whittington ◽  
TR Grant

Blood was collected from a bill sinus of nine conscious adult platypuses, Ornithorhynchus anatinus, caught in south-eastem New South Wales. Sexual dimorphisms were not found in the haematological and serum biochemical values measured. Results were compared with those obtained earlier from anaesthetized platypuses: ether anaethesia did not affect red cell parameters and the majority of biochemical values measured. It did, however, cause significant leukocytosis due to neutrophilia and monocytosis. The mean total leukocyte count in conscious platypuses was 28.63 X 10*9.1-�. The unusually high urea levels and low creatinine levels found in anaesthetized platypus were confirmed in this study (31.5 mmol.l-� and 26 �mol.l-� respectively). High values for erythrocyte count (9.96 X 10*12.l-�), packed cell volume (0.491.l-�) and haemoglobin (190 g.l-�) were found in conscious platypuses, confirming earlier findings and supporting the view that the erythrocyte parameters of the platypus show significant adaptations to hypoxia.


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