Mortality factors acting on adult rabbits in central-western New South Wales

2000 ◽  
Vol 27 (6) ◽  
pp. 613 ◽  
Author(s):  
Andrew Moriarty ◽  
Glen Saunders ◽  
Barry J. Richardson
Keyword(s):  
New South ◽  
New South Wales ◽  
Adult Rabbit ◽  
Mortality Factors ◽  
South Wales ◽  
Rabbit Haemorrhagic Disease ◽  
Surface Dwelling ◽  
One Year ◽  
Haemorrhagic Disease ◽  
Overall Mortality

Mortality of radio-tagged adult rabbits (Oryctolagus cuniculus) (n = 274) was monitored for one year in central-western New South Wales. The overall mortality rate was 82%. Predation was the most important and consistent cause of adult rabbit mortality, accounting for 44% of the total number of rabbits, followed by Rabbit Haemorrhagic Disease (RHD) (16%), myxomatosis (9%), unknown causes (9%), and enteritis/peritonitis (2%). Foxes were the most important predators, accounting for 28% of radio-tagged rabbits. Medium to large birds of prey were less important, accounting for 10%, followed by cats, which were responsible for 6% of the deaths of radio-collared rabbits. Myxomatosis outbreaks occurred in February/March and November–January. An RHD outbreak occurred during July, with 40% of the adult rabbit population being killed. The number of male and female radio-collared adult rabbits killed by each mortality agent throughout the year was similar. The proportions of warren-dwelling rabbits and surface-dwelling, solitary rabbits killed were similar overall; however, a significantly higher number of warren-dwelling rabbits were killed by myxomatosis and a significantly higher number of surface-dwelling rabbits were killed by RHD.

scholarly journals Initial effects of rabbit haemorrhagic disease on free-living rabbit (Oryctolagus cuniculus) populations in central-western New South Wales

1999 ◽  
Vol 26 (1) ◽  
pp. 69 ◽  
Author(s):  
Glen Saunders ◽  
David Choquenot ◽  
John McIlroy ◽  
Rossanne Packwood
Keyword(s):  
New South ◽  
New South Wales ◽  
Free Living ◽  
The Third ◽  
Rates Of Change ◽  
South Wales ◽  
Rabbit Haemorrhagic Disease ◽  
Haemorrhagic Disease ◽  
Variable Influence ◽  
Two Populations

Quarterly spotlight counts of rabbits were conducted at three sites in central-western New South Wales. These counts commenced two years before the arrival of rabbit haemorrhagic disease (RHD) in the winter of 1996. The existing data on quarterly rates of change in rabbit abundance for the three populations provided a unique opportunity to study the effects of RHD on rabbit demography. Prior to the arrival of RHD, all three populations underwent phases of sequential increase and decrease in each year. On the basis of these patterns, RHD had a variable influence on the demography of the three rabbit populations. In 1996–97, the density of two populations declined over an expected period of increase, while at the third site the density increased as expected from pre-RHD patterns. Twelve months after their failure to generate expected positive rates of increase the two affected populations had returned to the normal sequence of increases and decreases in density although still at comparatively low numbers.

Overwintering of Tranzchelia discolor in prune orchards in New South Wales

1987 ◽  
Vol 38 (5) ◽  
pp. 895 ◽  
Author(s):  
PJ Ellison ◽  
L McFadyen ◽  
PF Kable
Keyword(s):  
Leaf Litter ◽  
New South ◽  
New South Wales ◽  
Cross Infection ◽  
Infected Leaf ◽  
South Wales ◽  
One Year ◽  
Tranzschelia Discolor ◽  
Better Than

There are several ways in which Tranzschelia discolor may overwinter in prune orchards in the Murrumbidgee Irrigation Areas of New South Wales. The aecial state, cross-infection from peach and almond, twig cankers, and urediniospores on living leaves persisting through winter were considered, but were thought to be unlikely. The ability of urediniospores to survive on infected leaf litter, either on the ground under trees or lodged within the framework of trees, was studied over two winters. Urediniospore viability declined with time, but in both seasons a proportion were capable of germination in the spring. Spores exposed within the tree framework survived better than those exposed on the ground, with about 20% and less than 5% respectively remaining viable by spring. In both winters spores from litter which overwintered within the framework of the tree were able to infect prune leaves in the spring. The infectivity of spores exposed on the ground was tested in the spring of one year and infections resulted on inoculated plants. The implications of these findings for the control of the rust in prunes are discussed.

Production of summer crops in northern New South Wales. II. Effects of tillage and crop rotation on yields of sorghum

1992 ◽  
Vol 43 (1) ◽  
pp. 123 ◽  
Author(s):  
JF Holland ◽  
DF Herridge
Keyword(s):  
New South ◽  
New South Wales ◽  
Threshold Value ◽  
No Tillage ◽  
Tillage Practices ◽  
South Wales ◽  
Carry Over ◽  
One Year ◽  
N Fertility ◽  
Rotation Crop

Two crops of sorghum were grown in successive summer seasons at 3 sites on alkaline, black earth soils near Tamworth, New South Wales following either soyabeans, mungbeans, cowpeas, pigeonpeas, sunflowers or sorghum. Tillage practices were cultivation using a chisel plough and scarifier, and no-tillage using atrazine and glyphosate for weed control. Variation in grain yield (1.0-8.4 t/ha) was largely associated with variation in Dec.-Feb. rainfall (128-475 mm). An average of 15 kg grain/ha was produced for each mm water above the threshold value of 83 mm. At the high (Site A) and low (Site C) N-fertility sites, the rotation effect on sorghum yields was significant for one year, but did not carry over to a second sorghum crop. Cowpeas were the best rotation crop, followed by sunflowers mungbeans and soyabeans. At the low N-fertility site, sorghum following cowpeas outyielded sorghum after sorghum by 47% in the unfertilized plots and by an aExperiments to examine the effects of tillage practice and crop sequence on the production of sorghum grain in northern New South Wales are described. Two crops of sorghum were grown in successive seasons at three sites on alkaline, black earth soils near Tamworth following either soybean, mungbean, cowpea, pigeonpea, sunflower or sorghum. Tillage practices were cultivation using a chisel plough and scarifier, and no-tillage using atrazine and glyphosate for weed control. Variation in grain yield (1.0 to 8.4 t/ha) was largely associated with variation in December-February rainfall (128 to 475 mm). We calculated that an average of 15 kg/ha of grain was produced for each mm water above the threshold value of 83 rnm. At the high (Site A) and low (Site C) N-fertility sites, the rotation effect on sorghum yields was significant for one year, but did not carry over to a second sorghum crop. Cowpea was the best rotation crop, followed by sunflower, mungbean and soybean. At the low N-fertility site, sorghum following cowpea outyielded sorghum after sorghum by 47% in the unfertilized plots and by an average of 27% over all N treatments. It is likely that the increased yields of sorghum in the rotation plots resulted from higher levels of plant available N from both N2 fixation activity (legumes only) and reduced amounts of N removed with the harvested grain (particularly cowpea and sunflower). At the non-responsive, moderate-fertility Site B, water, rather than N, was limiting. Responses to no-tillage were apparent only in the very dry 1984/85 season (December to February rainfall, 42% below average). In the other three seasons, the cultivated crops outyielded the no-tilled crops or the differences between the two practices were not significant.

Dispersal of the Wild Rabbit, Oryctolagus cuniclus, at Urana in New South Wales

1982 ◽  
Vol 9 (3) ◽  
pp. 427 ◽  
Author(s):  
I Parer
Keyword(s):  
Natural Population ◽  
Significant Relationship ◽  
New South ◽  
New South Wales ◽  
Wild Rabbit ◽  
South Wales ◽  
One Year

In a natural population of rabbits, studied for 5 years, 307 dispersal movements by young rabbits were detected. Most movements occurred at the beginning of summer and more males moved than females. With the exception of one year there was no significant relationship between the ages of dispersing rabbits and the distances moved. Three rabbits, less than 1 month old, moved more than 1500 m. During a drought year the orientation of the movements was towards Lake Urana. Adult rabbits rarely changed warrens.

Aspects of Lactation in the Platypus, Ornithorhynchus anatinus (Monotremata), in Waters of Eastern New South Wales.

1983 ◽  
Vol 31 (6) ◽  
pp. 881 ◽  
Author(s):  
TR Grant ◽  
M Griffiths ◽  
RMC Leckie
Keyword(s):  
New South ◽  
New South Wales ◽  
Young Leave ◽  
South Wales ◽  
Ornithorhynchus Anatinus ◽  
Significant Difference ◽  
Lactating Females ◽  
One Year ◽  
The One ◽  
First Time

Female platypuses captured in waters of eastern New South Wales were found to be lactating between the months of October and March. Lactating females were most numerous in December, accounting for 64% of females captured. Non-lactating females were taken in all months, indicating that not all females breed successfully every year. There was no significant difference between the fatty acid complement of milk taken from a platypus lactating very late in the season and those of others sampled in December at the peak of the lactation season. Some evidence exists that females do not become reproductive until at least their second year of life. Some females were found lactating in consecutive years, and others lactated one year and not in the one following. Animals of over 9 years of age are known to breed. Most juveniles were captured in February, March and April, and it is suggested that the young leave the breeding burrows for the first time in late January through to March, and become independent from their mothers, who are ceasing lactation at that time.

A Review of Compulsory Admissions to a Psychiatric Unit in Sydney

1981 ◽  
Vol 15 (4) ◽  
pp. 307-310 ◽  
Author(s):  
John Snowdon
Keyword(s):  
Mental Health ◽  
Catchment Area ◽  
Total Population ◽  
New South ◽  
New South Wales ◽  
Main Criterion ◽  
Mental Health Act ◽  
South Wales ◽  
One Year

This study is concerned with compulsory admissions of patients from a defined catchment area of Sydney in 1979. The rate of such detentions under the present Mental Health Act in New South Wales was found to be about one per 1000 of the total population in one year. A much smaller proportion of psychotic than of non-psychotic patients was considered dangerous by doctors who signed the schedules, yet those (40%) requiring to be on compulsory orders after magisterial hearings were all diagnosed as psychotic. If dangerousness were to be the main criterion for compulsory detention under the Mental Health Act (as recently proposed), many psychotic patients could not legally be detained. Yet follow-up, as in this study, demonstrates the benefits of such admissions. Revision of proposed amendments is recommended.

Problems in assessing insecticidal control of Amnemus species (Coleoptera. Curculionidae) in clover pastures of north coastal New South Wales

1963 ◽  
Vol 54 (3) ◽  
pp. 523-533 ◽  
Author(s):  
B. M. Braithwaite ◽  
Annette Jane
Keyword(s):  
New South ◽  
New South Wales ◽  
Residual Effect ◽  
Soil Sampling ◽  
Patchy Distribution ◽  
South Wales ◽  
Second Year ◽  
Effect On Yield ◽  
One Year ◽  
Made In

Results are presented of 15 experiments made in north coastal districts of New South Wales from 1957 to 1961 with insecticides against the weevils Amnemus quadrituberculatus (Boh.) and A. superciliaris (Pasc.), the larvae of which have been reported as pests attacking the roots of clover (Trifolium repents, T. pratense and T. subterraneum) there. The adults live above ground, and single surface applications of insecticides were made to pastures in the form of dusts, granules or dilutions of emulsifiable concentrates in January, when maximum numbers of weevils were present and before significant oviposition had taken place. Insecticidal control was assessed by soil sampling for larvae in July–August, during the following winter. Pasture cuts were made in an attempt to assess the effect of treatments on the yield of clover.Dieldrin at rates of 2 and 4 lb. per acre gave near eradication of Amnemus for one year, and satisfactory control was obtained with 1 lb. per acre. Aldrin, endosulfan (Thiodan) and BHC were less effective, and limited tests with heptachlor suggested that it was inferior to dieldrin. The scanty results available suggest that dieldrin is effective against Amnemus for only one year, but it is doubtful if annual applications are warranted. Owing to the patchy distribution of clover in the pastures, only one experiment showed an increased yield of clover associated with the reduction in numbers of larvae of Amnemus brought about by the application of 1 lb. dieldrin per acre. Similarly, poor persistence of clover on all plots prevented assessment of any residual effect on yield in the second year.No method was found by which accurate estimates could be made of the density and distribution of adults of Amnemus in pastures to which insecticides were to be applied. Treatments, therefore, were replicated more frequently than was needed statistically in order to ensure that measurable levels of larval infestation were present at sufficient sites.Small plots (500–700 sq. ft.) proved of little value, and this is attributed not only to contamination of control plots but possibly also to the death of weevils that moved from untreated into treated plots. Large plots (13,000–21,000 sq. ft.) gave the most consistent results in assessment of insecticides.Control of Amnemus did not increase the productivity or persistence of clover, and it is concluded that any benefits from control are unlikely to be significant unless other factors, such as competition from grasses, drought, floods, nematodes and diseases of clover, which affected the density and persistence of clover in these experiments, are not limiting.

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