Region Of South-eastern Australia Research Articles

Predicting Ross River virus epidemics from regional weather data.

Diseases caused by arboviruses cause extensive mortality and morbidity throughout the world. Weather directly affects the breeding, abundance, and survival of mosquitoes, the principal vector of many arboviruses. The goal of this study was to test whether climate variables could predict with high levels of accuracy (more than 70%) epidemics of one arbovirus, Ross River virus disease. Weather data from two regions in southeastern Australia were matched with Ross River virus disease data for the period 1991 to 1999. Our aim was to develop simple models for the probability of the occurrence of an epidemic in an area in a given year. Two predictable epidemic patterns emerged, after either high summer rainfalls or high winter rainfalls. A prerequisite relating to host-virus dynamics was lower than average spring rainfall in the preepidemic year. The sensitivity of the model was 96% for Region 1 and 73% for Region 2. Early warning of weather conditions conducive to outbreaks of Ross River virus disease is possible at the regional level with a high degree of accuracy. Our models may have application as a decision tool for health authorities to use in risk-management planning.

Parameterising the impact of shelter on crop microclimates and evaporation fluxes

This paper presents the modelling framework and parameterisations adopted to enable the effects of wind shelter on crop microclimates and growth to be simulated. Two modelling components were required: the first, SCAM (Soil Canopy Atmosphere Model), is a biophysical land surface model used to simulate the effects of shelter on the plant canopy and soil energy and water exchanges. The second is the Agricultural Production Systems Simulator (APSIM) configured for crop modelling (Carberry et al. 2002). This paper describes the link between the two and the parameterisations developed to simulate the effects of shelter and provide potential evaporation estimates for input to APSIM. A series of sensitivity analyses using SCAM demonstrate, as expected, that over the course of the growing season and during meteorological conditions typical of agricultural regions in south-eastern Australia, plant evaporation is relatively insensitive to wind speed. This is consistent with theory and illustrates that reducing wind speeds will only reduce evaporation fluxes when the (unsheltered) canopy evaporation rate exceeds the equilibrium evaporation rate. In other words, reductions in water loss as a result of shelter will arise from one or a combination of the following: (i) reduced soil evaporation following rainfall; (ii) reduced evaporation of rainfall intercepted by the plant canopy; and (iii) reduced plant transpiration during wet periods and/or periods of very high demand when transpiration exceeds the equilibrium evaporation rate. Increased storage of soil moisture as a result of shelter early in the season may sustain crop transpiration later in the growing season. While this may not modify seasonal water use, increased soil water availability for the growing crop may confer an advantage in terms of final yield. The paper then describes the development and validation of a bulk scalar transfer coefficient, or resistance, based on wind tunnel experiments investigating scalar (heat and water vapour) transport in windbreak flows. This coefficient is used in SCAM to parameterise the effect of shelter on the exchanges of heat and water between the atmosphere and the soil and/or plant canopy. A simple parameterisation for this coefficient is developed and implemented. The potential effects of shelter on evaporative demand and hence plant growth are then quantified by using the predictions of plant potential evaporation, calculated from a modified version of SCAM as input to APSIM. The simulations show that events where reduced evaporative demand benefits plant growth can occur intermittently in the latter part of the growing season (i.e. post-anthesis for cereals) for some climatic regimes, as illustrated by the simulations for the Roseworthy, Esperance and Atherton sites used in the National Windbreaks Program.

Stratigraphy, sedimentary development and palaeoenvironmental context of a naturally accumulated pitfall cave deposit from southeastern Australia

McEachern's Deathtrap Cave (G—49/50) is located in the Lower Glenelg region of southeastern Australia and records a Late Pleistocene to Holocene sedimentary record that has been directly influenced by surface processes during its formation. The sedimentary sequence contained within the cave is divided into lower, middle and upper sequences consisting of eight facies. The lower sequence represents the earliest phase of sedimentation, and groundwater fluctuations during the Last Interglacial period resulted in its erosion and redistribution deeper into the cave system. A decrease in the magnitude and frequency of flood events in the cave during the formation of the middle sequence indicates increasingly drier surface conditions prior to the Last Glacial Maximum. The middle sequence has a minimum age of 9840 ± 290 a BP. Moving sand sheets during the Last Glacial blocked the entrance to the cave allowing flowstones to develop on the cave floor. The surface environment surrounding the cave was probably not as dry as contemporaneous inland sites because sedimentation continued to be dominated by flowing water during this period. Holocene sedimentation is represented by the upper sequence and reflects wetter cave conditions between 7680 ± 160 a BP and 5700 ± 110 a BP. A major phase of sediment accretion occurs after 5700 a BP and correlates to a phase of dune instability in the Lower Glenelg region. Flowing water remodelled the sediment cone sometime after 2240 ± 100 a BP, which represents a period of increased surface runoff, although it is not clear whether this is due to climatic or anthropogenic influences.

Using the Special Sensor Microwave Imager to Monitor Surface Wetness

The frequencies flown on the Special Sensor Microwave Imager (SSM/I) are sensitive to liquid water near the earth’s surface. These frequencies are primarily atmospheric window channels, which receive the majority of their radiation from the surface. Liquid water near the surface depresses the emissivity as a function of wavelength. The relationship between brightness temperatures at different frequencies is used to dynamically derive the amount of liquid water in each SSM/I observation at 1/38 resolution. These data are averaged at 18 resolution throughout the globe for each month during the period of 1992‐97, and the 6-yr monthly means and the monthly anomalies of the wetness index are computed from this base period. To quantify the relationship between precipitation and surface wetness, these anomalies are compared with precipitation anomalies derived from the Global Precipitation Climate Program. The analysis was performed for six agricultural regions across six continents. There is generally a good correspondence between the two variables. The correlation generally increases when the wetness index is compared with precipitation anomalies accumulated over a 2-month period. These results indicate that the wetness index has a strong correspondence to the upper layer of the soil moisture in many cultivated areas of the world. The region in southeastern Australia had the best relationship, with a correlation coefficient of 0.76. The Sahel, France, and Argentina showed that the wetness index had memory of precipitation anomalies from the previous months. The memory is shorter for southeastern Australia and central China. The weakest correlations occurred over the southeastern United States, where the surface is covered by dense vegetation. The unique signal, strengths, and weaknesses of the wetness index in each of the six study regions are discussed.

"In situ" Sporulation of "Phaemoniella chlamydospora" in the Vineyard

Summary. The fungus Phaeomoniella chlamydospora causes black goo decline of grapevines and is associated with esca, but little is known about its epidemiology. Sporulation was rarely observed on transversely-cut surfaces of naturally-infected roostocks and cordons of ten-year-old ‘Pinot Noir’ on ‘Ramsey’ grown near Geelong, Australia, over the winter months of 2000. However, abundant sporulation of the hyphomycete and pycnidial synanamorphs of P. chlamydospora were observed on protected wood surfaces inside deep cracks at the trial site. Sporulation in cracks was also observed on several grapevine varieties from other regions of south eastern Australia. Collembolans and mites were usually associated with the sporulation, but it is not known whether they have a role in dissemination of conidia.

Seasonal changes in the fraction of global radiation retained as net all-wave radiation and their hydrological implications

High linear correlation between concurrent measurements of net all-wave radiation Q*, and global incoming short-wave radiation Eg↓ was found for hourly, daytime and 24-h totals measured over a grassland catchment in the subhumid climate region of southeastern Australia. Five years of daily measurements were used to study the temporal variability in the fraction of incoming short-wave radiation retained at the surface as net all-wave radiation. When values of ξ = [Sgrave]Q*/[Sgrave]Eg↓ are calculated from 24-h totals and are plotted against date, the results reveal strong day-to-day and seasonal variability in ξ. Analysis indicated that the ξ ratio was largely determined by data, latitude and cloudiness, whilst the nature of the underlying surface appeared to play a less important role. Data from four other grassland sites in Australia, New Caledonia, Denmark and Ireland yielded a general relationship for estimating ξ from day length. Values of [Sgrave]Q* may thus be obtained from [Sgrave]Eg↓ observations using (a) a single regression between [Sgrave]Q* and [Sgrave]Eg↓ (b) monthly ξ values derived from measurements; or (c) monthly ξ values estimated from day length. All three approaches give estimates of [Sgrave]Q* with error terms similar to those of measurements of net all-wave radiation and those found when [Sgrave]Q* was estimated climatologically from the individual elements of the surface radiation balance—the standard method of obtaining this rarely measured but hydrologically important parameter. The hydrological impact of different methods of obtaining [Sgrave]Q* was demonstrated using the semi-distributed VIC catchment model to compute potential evapotranspiration for the 26 km2 Lockyersleigh catchment near Goulburn, New South Wales, Australia. The limited hydrological impact found is attributed to the fact that actual evapotranspiration in this subhumid catchment is limited by the strength of the soil water source rather than that of the atmospheric sink-potential evapotranspiration.

Restoration of a Native Grassland as Habitat for the Golden Sun Moth Synemon plana Walker (Lepidoptera; Castniidae) at Mount Piper, Australia

Synemon plana (golden sun moth) is a small diurnal moth from the family Castniidae, now listed as endangered in all regions of southeastern Australia in which it occurs. This study details an attempt to restore the native grassland habitat of S. plana at one site by increasing the cover of its probable food plant, Austrodanthonia eriantha (wallaby grass), to at least 40%, the average percentage cover determined from all currently inhabited sites. The percentage cover of A. eriantha increased when seedlings were planted, although there was no significant increase in cover by seeding caryopsides (dispersal units) or by weeding. However, combining weeding with planting seedlings, or seeding increased cover by 22% and 27% to 43% and 64%, respectively. Two hundred caryopsides per square meter (compared with only 49 seedlings/m 2 ) were required to increase cover to at least 40% due to the low viability of seeds and low germination in the field. Therefore, to restore grasslands dominated by A. eriantha as suitable habitat for S. plana, seedlings should be planted and weeds removed.

The influence of fire frequency on arbuscular mycorrhizal colonization in the shrub Dillwynia retorta (Wendland) Druce (Fabaceae)

Fire regimes have three inter-related components that can affect population dynamics: frequency, intensity and season. However, there has been little effort to study the effects of any of these components on arbuscular mycorrhizas (AM). In order to examine the long-term effects of fire frequency on AM colonization, the roots of Dillwynia retorta were examined at 32 sites supporting Hawkesbury Sandstone vegetation in the Sydney region of southeastern Australia. These sites were representative of the broad-scale variability in fire frequencies with respect to the length and timing of inter-fire intervals found in the Sydney region during the previous 30 years. The length of the shortest inter-fire interval was significantly correlated with total AM colonization, and the length of the longest inter-fire interval was related to the arbuscular colonization. The length of the most-recent inter-fire interval and the time since the shortest inter-fire interval were not related to AM colonization in D. retorta. Furthermore, AM colonization was directly related to the local abundance of the host plant, indicating that the effects of fire frequency on AM colonization are likely to occur indirectly via direct effects on the host plant. Canonical correspondence analysis demonstrated that the presence and abundance of alternate potential hosts had no influence on mycotrophy in D. retorta. Thus, the impact of fire on D. retorta was probably the main factor influencing its mycorrhizal status in relation to fire history.

Habitat of the Regent Honeyeater Xanthomyza phrygia and the value of the Bundarra-Barraba region for the conservation of avifauna

Five types of woodland and forest in the Bundarra-Barraba region of northern New South Wales were surveyed for Regent Honeyeaters Xanthomyza phrygia and other birds over two years. Regent Honeyeaters were found in 24 of the 93 transects, at a density of 0.09 birds/ha. Most were found in box-ironbark woodland (34% of 62 sites), with single records from box-gum woodland, box-stringybark woodland and dry plateau complex woodland. No Regent Honeyeaters were found in riparian gallery forest during censuses, but they were found breeding there at other times. All habitats contained a high density of birds, compared to other wooded regions in southern Australia, with riparian gallery forest and box-ironbark woodland being particularly rich in species and numbers. These habitats had greater flowering indices, larger trees and more mistletoes than other habitats. Sites used by Regent Honeyeaters supported significantly more birds and bird species than unoccupied sites. The region supports a total of 193 species, four of which are nationally threatened and seven which are threatened in New South Wales. The richness of the bird community in the region is partly because it retains a higher proportion of native vegetation cover (43%) than many other parts of rural Australia. Protection and rehabilitation of box-ironbark woodland and riparian gallery forest is of high priority in a regional conservation plan. However, all habitats in the Bundarra-Barraba region should be protected from clearing and degradation, because they are also used at times by Regent Honeyeaters and support a wide range of bird species. Wise management should retain many sensitive bird species that have disappeared from or declined in other regions of southeastern Australia.

The role of ants and mammals in dispersal and post-dispersal seed predation of the shrubs Grevillea (Proteaceae)

The role seed predators play in influencing the dynamics of plant populations has been little studied in Australia. The interaction of ant dispersal and seed predation on the soil seedbank in six shrubby species of Grevillea from the Sydney region of southeastern Australia was examined in selective exclusion experiments, seed array trials and placement of single seeds on the ground.

Influence of earthworms, Aporrectodea spp. (Lumbricidae), on lime burial in pasture soils in south-eastern Australia

The relative abilities of 3 exotic lumbricid earthworms, the endogeic Aporrectodea caliginosa and A. trapezoides and the anecic A. longa, to bury surface-applied lime and help ameliorate soil acidity were measured in cages in 7 pasture soils in south-eastern Australia. All 3 species buried lime, mostly within the top 5 cm of the soil profile, but A. longa buried it deeper than A. caliginosa and A. trapezoides. A. longa significantly increased soil pH at 15–20 cm depth at some sites within 5 months (winter–spring, the earthworm ‘season’ in the Mediterranean climate of south-eastern Australia). Lime burial varied markedly between sites. These site differences were explained, at least in part, by variations in rainfall. Lime burial increased with earthworm density. A minimum density of 214 A. longa/m 2 was needed to significantly enhance lime burial within one season. Higher densities were required for the other two species. However, per unit of biomass, A. caliginosa and A. trapezoides were generally more able to bury lime in the upper soil layers (2 . 5–10 cm depth) than A. longa. Agricultural soils in south-eastern Australia are dominated by shallow burrowing species such as A. caliginosa and A. trapezoides. Deeper burrowers such as A. longa are rare. Introduction of A. longa to soils in high-rainfall regions of south-eastern Australia, where it does not presently occur, should enhance lime burial and help reduce soil acidity.

Relative importance of natural and anthropogenic influences on the fresh surface water chemistry of the Hawkesbury–Nepean River, south-eastern Australia

Fresh surface waters from the Hawkesbury–Nepean River, the major river supplying water to the Sydney region in south-eastern Australia, were sampled monthly during 1991 and analysed for major ions (Na, K, Ca, Mg, Cl, SO 4 and HCO 3), nutrients (NO 3 and PO 4), organic carbon and trace metals (Al, Fe, Cu, Zn, Pb, Cd, Ni, Co and Mn). The chemical composition of the river during 1991 was consistent with other studies of the river from 1977 to 1996. The major ion composition in the river is predominantly influenced by sea-salt aerosols in rainwater (headwaters) and connate sea-salt in groundwater (mid-lower reaches), with a cationic dominance order of Na≫Mg>Ca>K (equivalents) and an anionic order of Cl≫HCO 3>SO 4. This is typical of the headwaters of other permanent coastal rivers (freshwater) in south-eastern Australia with a similar catchment lithology. These results differ markedly from the most common natural major ion assemblages established for world rivers (i.e. Ca>Mg>Na>K and HCO 3>SO 4>Cl), which tend to be predominantly influenced by chemical weathering of rocks and minerals. The mean concentrations of major ions, nutrients, organic carbon and trace metals in the freshwater reaches of the Hawkesbury–Nepean River increased by factors of 2.5–4.4, 14–18, 2.2 and 1.6–11, respectively, with increasing distance from the headwaters. Increases in major ion concentrations are attributed mainly to the increasing influence of saline groundwater inflows from regions of Wianamatta shale. Conversely, concentrations of nutrients, organic carbon and trace metals (except Fe and Al) increased as a consequence of anthropogenic inputs, particularly point discharges from sewage treatment plants (i.e. showing distinct, but variable, concentration peaks), as well as diffuse urban and/or agricultural runoff during storm events. The temporal variability of the mean concentrations of all measured parameters in this study was related to variability in water discharge. The mean concentrations of the major ions decreased by a factor of 1.5–3.0 with increasing water discharge, whereas the concentrations of nutrients, organic carbon and trace metals increased by a factor of 2.0–3.0, 1.6 and 1.3–2.0, respectively. This study provides the first survey of trace metal concentrations in the freshwater reaches of a permanent coastal river in Australia using `clean' sampling and handling techniques. The concentrations of Cu, Zn, Pb, Cd and Ni measured in the headwaters of the Hawkesbury–Nepean River were amongst the lowest reported in the literature for riverine (freshwater) systems, and will form a benchmark for assessing the effects of increasing urbanisation in the catchment.

A climatology of coastal ridging over south-eastern Australia

The dominant feature of sea-level pressure (SLP) patterns over the coastal regions of south-eastern Australia is the ridging that extends northwards along the coast. This ridging is particularly evident in the warmer months, October to March, when it is present on part or all of approximately 65 per cent of days, usually occurring in sequences ranging from one to several days. In this paper, three distinct forms of coastal ridging are identified, and are referred to as types 1, 2 and 3. Their distinguishing synoptic and subsynoptic characteristics are described. As well as their ubiquity and synoptic significance, all three types are important because each can generate severe weather of the following types: heavy precipitation, strong winds, or sudden changes in wind direction and temperature. Climatologies of the three types are prepared for the 20-year period 1974-1993 in the form of both monthly and annual frequencies of occurrence. Given that south-eastern Australia is one of the areas of the globe most affected by the El Nino-Southern Oscillation (ENSO), correlations are calculated between monthly ridging frequencies and monthly values of the Southern Oscillation Index (SOI). Also, annual frequencies are correlated with the annual (January to December) SOI value. Three diagnostic case studies are presented in considerable detail because they are very important to understand thoroughly the nature of and differences between the three types of ridging.

THE FORMATION AND SIGNIFICANCE OF CORALLINE SILICA SPELEOTHEMS IN THE SYDNEY BASIN, SOUTHEASTERN AUSTRALIA

The vast majority of speleothems are composed of calcium carbonate, but this paper focuses on a suite of less-commonly reported speleothems, those formed almost entirely of silica, and on a quartzose rather than carbonate base rock. On the quartz sandstones of the Sydney region of southeastern Australia, small branched coralline silica stalactites, up to 10 mm in diameter and 80 mm in length, frequently are found. These stalactites have not been described in detail before and are clear evidence of the solution of silica (including quartz) from within the sandstones, and its transport and redeposition at the rock surface. Detailed analysis using SEM, XRD, and thin-section techniques revealed layered composition of both amorphous opal-A and crypto-crystalline chalcedony. Calcite forms no part of these stalactites. The internal structure also shows that they do not form in a manner similar to calcite stalactites. While the growth rate of these silica stalactites remains unknown, it is believed to be quite slow. But they clearly are not relict features and are forming under present-day temperate-climatic conditions, not the tropical conditions demanded by some authors for silica stalactites elsewhere. Further detailed study of these and other silica speleothems is continuing, as they have the potential to be used as important records of palaeoclimatic and land-use change. [Key words: silica karst, speleothem, coralline silica, silica stalactite, opal-A, chalcedony, quartz, silica solution.]

Effectiveness of liming to minimise uptake of cadmium by wheat and barley grain grown in the field

The effects of soil pH on cadmium (Cd) concentration in wheat and barley grain were determined from 8 field experiments in the Rutherglen (Victoria) and Wagga Wagga (New South Wales) regions of south-eastern Australia. Generally, raising soil pHc, from 4.0 to 5.0 using lime decreased Cd concentration in the grain. However, the response was variable between sites and years, with the greatest variation occurring between years. At those sites where there were statistically significant decreases in Cd concentration with increasing pH, the rate of decrease was small. The Cd concentration exceeded the maximum permissible concentration (MPC) of 0.05 mg/kg in barley grain at 3 sites and in wheat at 1 site. In some cases, raising soil pHCa, to 6.0 was not sufficient to decrease Cd concentration in grain below the MPC and raising soil pH above this value would not be considered economically viable in many areas.

Effect of acetylene provided by wax-coated calcium carbide on transformations of urea nitrogen applied to an irrigated wheat crop

The effect of acetylene (provided by wax-coated calcium carbide, CaC2) on N transformations in a red-brown earth was measured in a field experiment with irrigated wheat by determining the change in the concentration and 15N enrichment of the organic N and mineral N pools with time. The study was conducted in the Goulburn-Murray Irrigation region of south-eastern Australia using 0.3 m by 0.3 m microplots fertilized with 15N-labelled urea (10 g N m-2; 5 atom% 15N). Acetylene was effective in slowing the nitrification of both unlabelled and labelled N. Nitrate derived from the added fertilizer reached a maximum 19 days after sowing in the treatment without CaC2, whereas little nitrate accumulated in the 8 g CaC2 m-2 treatment. There was significant immobilization of the urea N by 19 days after sowing in all treatments, but the extent of immobilization was not affected by the acetylene. The addition of acetylene slowed net mineralization of labelled and unlabelled N from the organic N pool, and resulted in increased accumulation of both unlabelled and labelled N in wheat tops.

Numerical Modeling of Orographically Forced Postfrontal Rain

Abstract A nonhydrostatic mesoscale model is used to simulate the dynamics and microphysics of postfrontal flow in the mountainous region of southeastern Australia. The aim of the paper is to determine if it is possible to use 2D models to simulate the characteristics of the liquid water field upstream from Baw Baw Plateau under postfrontal conditions. Results from both 2D and 3D simulations are compared with aircraft and surface observations taken during the Australian Winter Storms Experiment I, conducted during July and August 1988. The observations and both the 2D and 3D simulations show that under postfrontal conditions, the main feature of the flow is a series of standing lee waves downstream from Baw Baw Plateau. The microphysical fields are characterized by a cap cloud over Baw Baw Plateau and a region of high liquid water content extending at least 50 km upstream from the plateau. Convective elements form upstream from the plateau and are subsequently advected to the northeast. As the convective ...

Uptake of 15N-labelled nitrate by irrigated wheat

Uptake of nitrate (NO 3 - ) by wheat (cv. Condor) grown on a heavy clay soil in the Goulburn-Murray Irrigation Region of south-eastern Australia was investigated. 15N-labelled NO 3 - was applied at 2 gNm−2 on 7 September, 5 October and 5 November 1987 to microplots in a larger field experiment involving two irrigation treatments. The irrigation treatments were either complete irrigation until maturity or partial irrigation. Plant tops were harvested from three microplots selected at random from each treatment on 4 occasions; 7,14, 21 and 28 days after N application. Irrigation had no effect on the rate of uptake of 15N. Recovery of 15N-labelled NO 3 - in the plant tops increased from 50% for the September 15N addition to 70% for the October and November additions. The low recovery of 15N in September occurred when soil NO 3 - values were relatively high. Daily uptake of 15N-labelled NO 3 - ranged from 0.08 to 0.15g Nm−2 between September and November, whereas total N accumulation data indicated a mean N uptake of 0.17, 0.18 and 0.20 g Nm−2 d−1 during September, October and November, respectively.

Fertilizer nitrogen balance on spring irrigated malting barley

Fertilizer N balance on malting barley (Hordeum vulgare L. cv. Parwan) subjected to a factorial combination of three irrigation (rainfed, irrigated at 45 mm deficit, or irrigated at 85 mm deficit) and three15N fertilizer treatments (2.8, 4.5 and 9.1 g N m−2) was investigated. The crop was grown on a heavy clay soil in the Goulburn-Murray Irrigation Region of south-eastern Australia. Increasing the N application at sowing from 2.8 to 9.1 g N m−2, increased the accumulation of fertilizer N in barley grain from 0.36 to 2.0 g N m−2. Soil N was the major source of N in the grain and plant. Nitrogen uptake was not affected by the irrigation treatment or the application of N fertilizer. Nitrogen content of the grain was 1.57, 1.53 and 1.66% for crops receiving 2.8, 4.5 and 9.1 g N m−2 of fertilizer N at sowing, respectively. Nitrogen harvest index was unaffected by irrigation and fertilizer N application and averaged 81% (range 78–82%) for all crops.

Experimental Embryonation and Survival of Eggs of Capillaria-Hepatica (Nematoda) Under Mouse Burrow Conditions in Cereal-Growing Soils

The apparent absence of the nematode Capillaria hepatica in mice from regions of south-eastern Australia where plagues occur may be due to constraints on embryonation and survival of eggs in the mouse burrow, where C. hepatica is thought to be transmitted. Excavation of mouse burrows in the mallee wheatlands indicated that nest chambers generally were at depths of 200-400 mm. At these depths minimum and maximum weekly soil temperatures during the main period of mouse breeding ranged from 15 to 36.5�C and soil moisture contents were 14.5-32.8%. Embryonation and survival of C. hepatica eggs were assessed in the laboratory in three types of soil over these ranges of soil temperature and soil moisture content, emulating conditions of the mouse burrow. Two of the soil types, Walpeup sandy loan and Deniliquin riverine clay, are representative of the light and heavy soils, respectively, where mouse plagues occur in south-eastern Australia. The third type of soil was a potting mixture previously used experimentally and known to support a high rate of transmission of C. hepatica. Eggs were able to embryonate, and embryonated eggs to survive for 30 days, in each type of soil across the ranges of temperature and moisture content. The results further support the potential of C. hepatica to be used tactically in suppressing mouse numbers in the cereal-growing regions of south-eastern Australia.