The Dispersal of Cernuella-Virgata (Mollusca, Helicidae)

1988 ◽  
Vol 36 (5) ◽  
pp. 513 ◽  
Author(s):  
GH Baker
Keyword(s):  
South Australia ◽  
Land Snail ◽  
Early Summer ◽  
Permanent Pasture ◽  
Roadside Vegetation ◽  
Mark Release Recapture

The dispersal of the land snail Cernuella virgata was measured in South Australia by mark-release- recapture. Dispersal was not influenced by the paint used for marking, displacement of the snails during the marking process or crowding at release points. Snails moved out of a well-grazed permanent pasture to adjacent weedy roadside vegetation in early summer. They returned to the pasture in autumn. Factors which might direct this movement are discussed. Average movements varied between 0.1 and 0.4 m day-'. Some snails moved more than 25 m in one month in spring-summer and 50 m in 3 months in autumn-winter.

The ecology of sympatric scincid lizards (Ctenotus) in arid South Australia

1998 ◽  
Vol 46 (6) ◽  
pp. 617 ◽  
Author(s):  
J. L. Read
Keyword(s):  
Home Range ◽  
Environmental Conditions ◽  
Plant Material ◽  
Reproductive Effort ◽  
Arid Zone ◽  
South Australia ◽  
Early Summer ◽  
Home Ranges ◽  
Local Species ◽  
Olympic Dam

Ctenotus skinks are the most diverse and abundant diurnal reptile genus at Olympic Dam, in the South Australian arid zone. The home range, demography, reproduction and diet of five syntopic Ctenotus species was studied over a 6-year period in chenopod shrubland. Longevity frequently exceeded three years in C. regius, four years in C. schomburgkii and five years in C. leonhardii, with a 7-year-old specimen of C. leonhardii being recorded. Females of most species tended to be larger and lived longer than males. Two eggs were typically laid by each species in early summer. Annual reproductive effort, particularly in C. leonhardii, varied considerably depending upon the prevailing environmental conditions. All local species apparently occupied home ranges, with maximum recapture radii in different species of 40–60 m. Ctenotus appear to be unspecialised insectivores, although plant material and lizards are sometimes eaten by the larger species.

Population Dynamics and Movement Patterns of Bolam's Mouse, Pseudomys bolami, at Roxby Downs, South Australia.

1998 ◽  
Vol 20 (3) ◽  
pp. 353
Author(s):  
K.E. Moseby ◽  
J.L. Read
Keyword(s):  
Arid Zone ◽  
Sand Dunes ◽  
South Australia ◽  
Breeding Strategy ◽  
Early Summer ◽  
Ecological Data ◽  
Winter Rainfall ◽  
Land Systems ◽  
Single Night ◽  
Time Of Year

Basic ecological data were collected on Bolam's mouse, Pseudomys bolami, during a six year trapping study at Roxby Downs in northern South Australia. Pseudomys bolami inhabited mixed arid land systems in the Roxby Downs area, sheltering in the longitudinal orange sand dunes but foraging at night principally on the adjacent chenopod swales. Distances of up to 334m were traversed in a single night and recapture rates were high within trapping sessions but low between sessions suggesting wide-ranging movements and short-term residency. Dietary observations imply an omnivorous diet. Whilst the closely related P. hermannsburgensis is regarded as having an opportunistic breeding strategy, P. bolami reproduced opportunistically but also regularly in spring and early summer. Different reproductive strategies may be influenced by the latitudinal distribution of P. bolami near the southern margin of the arid-zone, where rainfall can occur at any time of year but winter rainfall is more predictable. This contrasts with P. hermannsburgensis, which inhabits more northerly arid areas where rainfall is erratic and unpredictable. There was a 10 fold fluctuation in P. bolami captures over the trapping period with numbers of P. bolami and house mice, Mus domesticus peaking 12 months after above average rains during 1992. Rodent captures remained high for two years afterwards. Although P. bolami persisted throughout the study period, M. domesticus was only present when conditions were above average. Trap success of P. bolami or M. domesticus did not vary between the five sub habitats at the 1 ha study site. However, trap success of P. bolami was positively related to vegetation cover, particularly cover of low bluebush, Maireana astrotricha. Maireana astrotricha may be important in providing both food and cover for P. bolami, a scenario consistent with the utilisation of spinifex, Triodia spp. by P. hermannsburgensis in the northern arid-zone. Past over- grazing of chenopod shrublands may have reduced cover and contributed to the suggested decline in the distribution of P. bolami.

Some aspects of the ecology of the land snail, Helicella virgata, in South Australia

1969 ◽  
Vol 17 (3) ◽  
pp. 495 ◽  
Author(s):  
DE Pomeroy
Keyword(s):  
Natural History ◽  
Natural Population ◽  
South Australia ◽  
Growth Curves ◽  
Land Snail ◽  
Food Resources ◽  
Winter Dormancy ◽  
Rate Of Growth ◽  
Length Of Life

H. virgata was introduced to South Australia from Europe and has since become remarkably numerous. Its natural history is described, including breeding, growth, and food. There is normally one generation per year, the eggs mostly hatching in autumn and the young growing rapidly until spring. Marking and recapture were used to determine growth curves in the field. Snails are only active when the ground is moist and the humidity high. Even in winter dormancy is frequent, and in summer it is prolonged. H. virgata is microphagous, feeding mainly on the topsoil and surface litter, avoiding places from which these are removed. It was shown experimentally that the numbers of young produced, their rate of growth, and the length of life of adults all decreased with increasing density. This was explained in terms of increasing starvation. A natural population was studied for nearly 2 years. In places the density of this population was high and there was evidence of a consequent shortage of food, which affected young and adults differently. "Effective fecundity" (p. 509) was inversely proportional to the density of the population. There were marked aggregations, apparently reflecting the distribution of food. However, the degree of "patchiness" (Lloyd 1967) remained fairly constant with time. Over most of its range H. virgata is relatively scarce and the numbers in these places are less likely to press upon the food resources. The effects of cultivation and trampling, lack of calcium in the soil, and other factors must explain this scarcity. Weather can certainly be important; the drought of 1965-66 reduced all populations severely.

Controlling redlegged earth mite, Halotydeus destructor (Acari: Penthaleidae), with a spring spray in legume pastures

2015 ◽  
Vol 66 (9) ◽  
pp. 938 ◽  
Author(s):  
T. J. Ridsdill-Smith ◽  
C. C. Pavri
Keyword(s):  
Seed Yield ◽  
South Australia ◽  
Subterranean Clover ◽  
Early Summer ◽  
Eastern Region ◽  
The West ◽  
Halotydeus Destructor ◽  
South Wales ◽  
Redlegged Earth Mite ◽  
Clover Seed

The use of a TIMERITE® spring spray to control redlegged earth mite (RLEM), Halotydeus destructor (Tucker) (Acari: Penthaleidae), in annual pastures was evaluated on farms across Australia. RLEM populations in autumn in the treatments sprayed in spring 1998 and 1999 were 97% lower in 1999 and 97% in 2000 in the western region (Western Australia), and 93% lower in 1999 and 93% in 2000 in the eastern region (Victoria, New South Wales and South Australia). At sites in the west, control of RLEM resulted in significant increases in subterranean clover seed yield in 1999 and in clover seedling numbers in autumn 1999 and 2000. Penthaleus major (blue oat mite) populations in autumn were 60% lower in sprayed treatments, but Sminthurus viridis (lucerne flea) populations were not affected. Differences in weather between the west (where there is a hot, dry summer) and the east (where temperature and rainfall regimes are more variable in spring and early summer) seem to cause greater RLEM control and greater benefits in subterranean clover seed yield and seedling numbers with a spring spray in the west.

Ecology of Pinna bicolor gmelin (Mollusca : Bivalvia) in Gulf St Vincent, South Australia: density, reproductive cycle, recruitment, growth and mortality at three sites

1987 ◽  
Vol 38 (6) ◽  
pp. 743 ◽  
Author(s):  
AJ Butler
Keyword(s):  
Mortality Rate ◽  
Reproductive Cycle ◽  
Shell Length ◽  
South Australia ◽  
Maximum Size ◽  
Adult Mortality ◽  
Early Summer ◽  
Random Samples ◽  
Intertidal Site

Random samples of P. bicolor were taken from one intertidal and two subtidal sites over 3 years and tagged individuals of P. bicolor were followed for up to 6 years at two other sites. P. bicolor is dioecious. Mature gonads were observed in early summer (November-January) with a peak in December each year. The pattern appeared to differ little between years or sites but the period of maximum gonad activity was shorter at the intertidal site. Growth was slower at the intertidal site and animals reached a smaller maximum size there than at the subtidal sites, which differed slightly. It is concluded that P. bicolor can reach reproductive size (15 cm shell length) in little more than a year but, at least subtidally, have a low mortality rate (less than 0.1 year-1) thereafter. Recruitment is variable and it is argued that at some sites superficially 'stable' densities of P. bicolor are maintained by occasional strong recruitments, which are 'stored' in the population because of low adult mortality. The implications of this for management and for the use of P. bicolor as a biological monitor are discussed.

Occurrence and identity of Puccinia graminis on wheat, barley, andgrasses in Australia during summer - autumn 1992-93

1997 ◽  
Vol 48 (7) ◽  
pp. 999 ◽  
Author(s):  
R. F. Park
Keyword(s):  
Western Australia ◽  
Resistance Genes ◽  
Stem Rust ◽  
South Australia ◽  
Early Summer ◽  
Grass Species ◽  
Puccinia Graminis ◽  
Australian Wheat ◽  
Greenhouse Tests

Levels of stem rust (Puccinia graminis) in Australian wheat and barley crops were generally low from 1980 to 1992. Exceptionally wet conditions in South Australia (SA) during early summer 1992-93 resulted in the establishment of vast areas of self-sown cereals, in which stem rust increased rapidly. The disease was also more common in Western Australia during the summer months of 1992-93. Collections from rusted wheat, barley, and selected grass species were analysed in greenhouse tests using an array of differential cereal genotypes. Five pathotypes of P. graminis f. sp. tritici were recovered from SA, 3 of which had not been isolated over the previous 10 years in Australia and for up to 20 years in SA. The recurrence of these pathotypes highlights the need for caution in redeploying resistance genes for which virulence has not been detected for several years. The majority (79%) of isolates taken from stem-rusted barley in SA were either P. graminis f. sp. secalis or `scabrum" rust, both of which do not infect wheat. In total, 6 of 7 isolates of pathotype 21-2,7 recovered from SA came from stem-rusted barley, and as most wheats in this region are resistant to this pathotype, it appears that hosts other than wheat must be important in perpetuating such avirulent pathotypes.

Napier subterranean clover (Trifolium subterraneum L. var. yanninicum)

2006 ◽  
Vol 46 (8) ◽  
pp. 1109 ◽  
Author(s):  
P. G. H. Nichols ◽  
M. J. Barbetti ◽  
P. M. Evans ◽  
A. D. Craig ◽  
G. A. Sandral ◽  
...  
Keyword(s):  
South Australia ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Improvement Program ◽  
Phytophthora Root Rot ◽  
Growing Season Length ◽  
Permanent Pasture ◽  
South Wales ◽  
Vigorous Growth ◽  
Water Holding

Napier is a late flowering F6-derived crossbred subterranean clover of var. yanninicum [(Katz. et Morley) Zohary and Heller] developed by the collaborating organisations of the National Annual Pasture Legume Improvement Program. It is a replacement for both Larisa and Meteora and has been selected for release on the basis of its greater herbage and seed production and disease resistance to both known races of clover scorch and 2 of the common races of Phytophthora root rot. Napier is recommended for sowing in Victoria, Western Australia, New South Wales, and South Australia. It is best suited to moderately acidic soils prone to water-logging and to loamy and clay soils with good water-holding capacity in areas with a minimum growing season length of 7.5 months, which extends into late November. Napier is well adapted to the permanent pasture systems found in the areas in which it will be grown. Its upright, vigorous growth makes it well suited to grazing by cattle or sheep and to fodder conservation. Napier has been granted Plant Breeders Rights in Australia.

Observations on the ecology of the Australian field cricket, Gryllulus commodus Walker, in the field.

1954 ◽  
Vol 2 (2) ◽  
pp. 205 ◽  
Author(s):  
TO Browning
Keyword(s):  
South Australia ◽  
Agricultural Practices ◽  
Field Cricket ◽  
Survey Method ◽  
Differential Survival ◽  
South Eastern ◽  
Permanent Pasture ◽  
Black Clay ◽  
Dry Conditions ◽  
History Of

Gryllulus commodus has one generation each year, the active stages being present in summer and autumn and the eggs in winter and spring. Crickets are found in abundance only in areas where the soil is heavy black clay. This affords shelter from desiccation to the eggs, which lose water very rapidly if exposed to dry conditions. Also in these areas there may be an abundance of food for the nymphs and adults, in the form of sown permanent pasture. Where either shelter for the eggs or food for the active stages is lacking the numbers of crickets tend to be lower. Certain aspects of the behaviour and physiology of G. commodus which are important in relation to the survival and multiplication of the species are discussed. The relative chanses in the abundance of crickets in the south-eastern districts of South Australia were determined by a survey method during the period 1949-52. Evidence is presented that differences In the abundance of crickets from year to year are mainly attributable to differences in the amount and distribution of rainfall during the winter and spring, which result in differential survival of the eggs. The history of cricket outbreaks in South Australia is traced and it is concluded that, if present trends in agricultural practices continue, future outbreaks will tend to be more severe and more widespread, although probably not more frequent.

Improving the efficiency of wildlife monitoring by estimating detectability: a case study of foxes (Vulpes vulpes) on the Eyre Peninsula, South Australia

2005 ◽  
Vol 32 (3) ◽  
pp. 253 ◽  
Author(s):  
S. A. Field ◽  
A. J. Tyre ◽  
K. H. Thorn ◽  
P. J. O'Connor ◽  
H. P. Possingham
Keyword(s):  
Practical Importance ◽  
Monitoring Program ◽  
South Australia ◽  
Monitoring Data ◽  
Pest Species ◽  
Ecological Inference ◽  
Roadside Vegetation ◽  
Wide Range ◽  
The Status ◽  
The Impact

Demonstrating the existence of trends in monitoring data is of increasing practical importance to conservation managers wishing to preserve threatened species or reduce the impact of pest species. However, the ability to do so can be compromised if the species in question has low detectability and the true occupancy level or abundance of the species is thus obscured. Zero-inflated models that explicitly model detectability improve the ability to make sound ecological inference in such situations. In this paper we apply an occupancy model including detectability to data from the initial stages of a fox-monitoring program on the Eyre Peninsula, South Australia. We find that detectability is extremely low (<18%) and varies according to season and the presence or absence of roadside vegetation. We show that simple methods of using monitoring data to inform management, such as plotting the raw data or performing logistic regression, fail to accurately diagnose either the status of the fox population or its trajectory over time. We use the results of the detectability model to consider how future monitoring could be redesigned to achieve efficiency gains. A wide range of monitoring programs could benefit from similar analyses, as part of an active adaptive approach to improving monitoring and management.

Phylogenetic systematics of the land snail Basedowena from the Australian arid zone: taxonomic revision with description of new taxa (Stylommatophora : Camaenidae)

2016 ◽  
Vol 30 (4) ◽  
pp. 370 ◽  
Author(s):  
Francesco Criscione ◽  
Frank Köhler
Keyword(s):  
New Taxa ◽  
Arid Zone ◽  
New South ◽  
South Australia ◽  
Taxonomic Revision ◽  
Land Snail ◽  
Shell Shape ◽  
Mountain Ranges ◽  
South Wales ◽  
Mitochondrial Phylogeny

The land snail Basedowena Iredale, 1937 currently comprises eight species that inhabit mountain ranges in the central Australian arid zone. By studying the variation in shell and genital anatomy and the differentiation in the mitochondrial markers 16S and COI, we revise the taxonomy of this camaenid and describe new taxa. We demonstrate that the current morphology-based classification has been misled by homoplasy mainly in shell shape. In fact, Basedowena as herein revised contains species with vastly different shells, which have so far been assigned to different genera. By contrast, these species have the same general genital anatomy in common and form a clade in the mitochondrial phylogeny. Based on these findings, we transfer Pleuroxia bethana, P. hinsbyi, P. elfina, P. oligopleura, P. polypleura, P. radiata, Montanomelon angatjana and Minimelon colmani to Basedowena. While Pleuroxia and Montanomelon are maintained as distinct genera, although with fewer species, the monotypic Minimelon becomes a junior synonym of Basedowena. We identify and describe three new Basedowena species (B. bicolor, sp. nov., B. holoserica, sp. nov., B. siparium, sp. nov.). A fourth new species differs substantially from all other arid zone camaenids and is hence placed in a new genus, Xeromelon, gen. nov. The revised delineation of Basedowena renders it now the most widespread camaenid genus in Australia. It is distributed throughout the Australian arid zone from Western Australia, via the Northern Territory and South Australia into New South Wales.

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