On the population dynamics of the Eucalypt-defoliating sawfly Perga affinis affinis Kirby (Hymenoptera)

1969 ◽  
Vol 17 (1) ◽  
pp. 113 ◽  
Author(s):  
PB Carne
Keyword(s):  
Population Dynamics ◽  
New South ◽  
Weather Data ◽  
Subsequent Generation ◽  
Study Region ◽  
South Wales ◽  
North Eastern ◽  
Causes Of Mortality ◽  
Very High

Changes of the abundance of the sawfly P. a. affinis were recorded during eight successive years in a study region extending from the Southern Tablelands of New South Wales to north-eastern Victoria. The influences and processes which affected mortality and reproduction in populations of the sawfly are described, and their contributions to the observed fluctuations of abundance in the study region are discussed. The major causes of mortality were desiccation, fungal disease, and parasitism. The main parasites were tachinids (Froggattimyia spp.) and a trigonalid (Taeniogonalos venatoria Riek). A variable proportion of the prepupae entered a diapause which persisted for 2 or more years. Although extended diapause ensured the survival of the subspecies during seasons unfavourable for its active stages, only a small proportion of the prepupae involved survived to emerge as adults. The consequences of very high numbers were: increased incidence of desiccation mortality and of extended diapause, and a decrease of the fecundity of the subsequent generation. Due to the benefits which accrued from colonial behaviour, survival of the larvae was greater at moderately high than at low densities. These density-regulating mechanisms of the life system of the sawfly operated conspicuously only at very high and very low densities. In the eastern portion of the study region, fluctuations of abundance were closely synchronized in all sites. These fluctuations could be interpreted in terms of changing environmental favourability during successive seasons. Analysis of weather data showed that departures from long-term average temperatures and rainfalls were correlated throughout the region. However, sawfly numbers fluctuated erratically in the western subregion, the changes of density there often being at variance with those consistent throughout the eastern subregion. Parasitism by T. venatoria, which was often very severe in the western subregion, was the only process recognized that was likely to be responsible for the differences observed.

Population attributes of the spotted-tailed quoll (Dasyurus maculatus) in north-eastern New South Wales

2008 ◽  
Vol 56 (2) ◽  
pp. 137 ◽  
Author(s):  
A. S. Glen
Keyword(s):  
Population Dynamics ◽  
New South ◽  
New South Wales ◽  
High Abundance ◽  
Morphometric Data ◽  
Wild Populations ◽  
Apparent Survival ◽  
South Wales ◽  
Eastern Australia ◽  
North Eastern

The spotted-tailed quoll (Dasyurus maculatus) is an endangered marsupial carnivore endemic to eastern Australia. A paucity of information on the dynamics of wild populations has hindered conservation of the species. The population dynamics of spotted-tailed quolls were investigated in an area of unusually high abundance in north-eastern New South Wales, where density is conservatively estimated at 0.3 km−2. Sixty individual quolls were captured on 331 occasions over 22 months. Apparent survival, timing and rate of reproduction, and morphometric data were compared with those of quolls from other areas. Population models were employed to investigate patterns in the behaviour and apparent survival of quolls in the study area. The high abundance of D. maculatus identifies the study area as vital to the conservation of quolls on mainland Australia, and to the future study of the species.

The biology, origin and adaptation of the Miniopterus australis (Chiroptera) in New South Wales

1968 ◽  
Vol 16 (1) ◽  
pp. 49 ◽  
Author(s):  
PD Dwyer
Keyword(s):  
New South ◽  
New South Wales ◽  
Southern Limit ◽  
South Wales ◽  
Coastal Belt ◽  
Long Term Effect ◽  
North Eastern ◽  
C 30 ◽  
Reproductive Events

The biology of Miniopterus australis was investigated in north-eastern New South Wales (latitude c. 30�S) between 1960 and 1966. In this area the species reaches the southern limit of its distribution and is largely confined to the subtropical coastal belt. Mating occurs in the winter months June and July, and is followed by a period of retarded embryonic development to mid-September. Births occur in December. The only nursery colony of M. australis located was that of the southernmost population of the species. It included about 4000 individuals (approximately 1800 young) in December and was intimately associated with a much larger nursery colony of M. schreibersii. A comparison of the winter behaviour of M. australis with that of M. schreibersii at the same latitude revealed that pre-winter increase in weight is less marked, that feeding behaviour persists longer, and that there are fewer, and less rigid, periods of torpidity in the former species. In its reproductive and wintering characteristics M. australis, at 30�S., has diverged less from the tropical, and presumably ancestral, pattern for the genus than has M. schreibersii at the same latitude. It is argued that M. australis has colonized New South Wales from low latitudes later than M. schreibersii and that colonization southwards may have been dependent upon, or promoted by, the prior existence of M. schreibersii nursery colonies. An analysis of retrapping data for the southernmost population of M. australis suggests that this is represented as two subpopulations (highland and lowland) between which adult individuals seldom exchange. Spermatogenesis, and hence mating, occurs slightly earlier in the highland subpopulation. It is suggested that earlier mating in this subpopulation may be selectively advantageous, and that the long-term effect of selection here could be to shift the timing of reproductive events in the entire population back towards that observed in M. schreibersii. Earlier mating should be correlated with a stronger manifestation of pre-winter increase in weight and of winter torpidity. The combination of all these changes in M. australis would permit further range expansion to the south and west, provided that suitable nursery sites are available and can be found.

Population stability in the endangered Fleay’s barred frog (Mixophyes fleayi) and a program for long-term monitoring

2015 ◽  
Vol 63 (3) ◽  
pp. 214 ◽  
Author(s):  
Gemma Quick ◽  
Ross L. Goldingay ◽  
Jonathan Parkyn ◽  
David A. Newell
Keyword(s):  
National Park ◽  
New South ◽  
Monitoring Program ◽  
Population Monitoring ◽  
Population Stability ◽  
South Wales ◽  
Long Term Monitoring ◽  
Term Monitoring ◽  
Very High

In the wake of the global decline in amphibians there is a need for long-term population monitoring. Previous research suggested that the endangered Fleay’s barred frog (Mixophyes fleayi) had recovered after a severe decline. We aimed to determine whether this recovery has been sustained and to test an example of a monitoring program that could be employed at intervals of five or more years to assess long-term population stability. We conducted capture–mark–recapture five years after the last detailed census at Brindle Creek in Border Ranges National Park, New South Wales. Frogs were captured along a 200 m creek transect between September 2013 and February 2014. We used program Mark to estimate demographic parameters of adult male frogs using two modelling approaches: robust design (RD) and the POPAN formulation of the Jolly–Seber model. Abundance was estimated at 38.2 ± 0.5 (s.e.) (RD) and 46.0 ± 2.7 (POPAN). Abundance in 2008 was estimated at 53.2 ± 10.0 (POPAN) male frogs. Estimates of apparent monthly survival over our five-month-long study were very high (RD: 1.0 ± 0.0; POPAN: 1.0 ± 0.02). Recapture estimates were also high (RD: 0.40 ± 0.07 to 0.72 ± 0.05 per session; POPAN: 0.84 ± 0.05 per month). These data suggest that the Brindle Creek population has remained relatively stable over a period of ~10 years.

Goat and Sheep Grazing in Shrub-Infested Semi-arid Woodlands of New South Wales.

1986 ◽  
Vol 8 (2) ◽  
pp. 140 ◽  
Author(s):  
BH Downing
Keyword(s):  
Animal Species ◽  
New South ◽  
Economic Implications ◽  
Dietary Preferences ◽  
South Wales ◽  
Continuous Grazing ◽  
Local Observation ◽  
Grazing Systems ◽  
Western Division

Examination of data on dietary preferences of sheep, goats and cattle suggests that different grazing systems are desirable for each of the three major woodland types (belah-rosewood, mulga, poplar box) examined. Competition for herbs, frequently palatable to all animal species, indicates that goats and sheep are unsuitable for joint use either in heavily wooded country or where annual herbaceous production is less than 200 kg-ha. Supplementary feeding, fire and judicious stocking are proposed as a strategy for inducing goats to eat a proportion of unpalatable shrubs. The literature provides little helpful information on how rangelands in the Western Division should be managed. No reports are given on comparisons of grazing systems, such as rotational grazing, rotational resting, and continuous grazing. No guidance is given on grazing after burning of the rangeland. Recommendations are generally against the use of goats for control of woody plants, whereas local observation shows this to be an apparently effective practice. The recommendations are mostly based on experimental procedures which, although suitable for detecting animal dietary preferences in the short term, are less appropriate for investigation of the effects of grazing on range condition in the long term. Some suggestions are made towards a different approach for: investigating the effects of grazing by sheep and goats on rangeland condition, and the economic implications of this in terms of animal production.

Effectiveness of protected areas in north-eastern New South Wales: recent trends in six measures

2002 ◽  
Vol 106 (1) ◽  
pp. 57-69 ◽  
Author(s):  
R.L Pressey ◽  
G.L Whish ◽  
T.W Barrett ◽  
M.E Watts
Keyword(s):  
Protected Areas ◽  
New South ◽  
New South Wales ◽  
South Wales ◽  
North Eastern ◽  
Recent Trends

Outflow ignimbrite sheets from Late Carboniferous calderas, Currabubula Formation, New South Wales, Australia

1983 ◽  
Vol 120 (5) ◽  
pp. 487-503 ◽  
Author(s):  
J. McPhie
Keyword(s):  
New South ◽  
Sedimentary Facies ◽  
Late Carboniferous ◽  
The West ◽  
Pyroclastic Deposits ◽  
Flow Units ◽  
South Wales ◽  
Accretionary Lapilli ◽  
North Eastern ◽  
Thickness Variations

SummaryRegionally mappable, silicic, outflow ignimbrite sheets are interbedded with fluvial volcanogenic conglomerates and sandstones of the Late Carboniferous Currabubula Formation of north-eastern N.S.W. Four of the most widespread of these ignimbrites are described and defined as members. The oldest member is comprised of many thin, originally non-welded flow units. Interbedded accretionary lapilli horizons may indicate phreatomagmatic activity at vent during the eruption in addition to local rain-flushing of co-ignimbrite ash clouds. Of the three other members, two are multiple flow-unit sheets, 160–180 m in aggregate thickness. Substantial portions of these sheets were originally welded. The remaining member is a simple welded ignimbrite characterized by abundant spherulites and lithophysae. Irregular pre-eruption topography and contemporaneous erosion were responsible for thickness variations of the ignimbrite sheets. Some palaeovalleys, now delineated by the ignimbrites, persisted in spite of repeated pyroclastic influxes. Relic pumice, shards and crystal fragments are ubiquitous components of the sedimentary facies of the Currabubula Formation, and were probably derived from originally poorly consolidated pyroclastic deposits such as airfall ash layers and non-welded ignimbrites. No surface trace of the sources of these ignimbrites exists. However, internal facies, thickness variations and volumes of the ignimbrites indicate that they periodically emanated from a multiple-caldera terrain which was continuously active during the Late Carboniferous, and located several kilometres to the west of present exposures.

Sydney rock oyster farming in Australia.

2020 ◽  
Author(s):  
John Nell
Keyword(s):  
New South ◽  
Quality Assurance Program ◽  
First Year ◽  
Water Sampling ◽  
Time To Market ◽  
Profit Margins ◽  
Rock Oyster ◽  
South Wales ◽  
Sampling Programme

Abstract The 120-year-old Sydney rock oyster industry in New South Wales (NSW) and southern Queensland is one of the oldest aquaculture industries in Australia. The industry has been forced to adapt to competition from other species, tighter harvesting and oyster storage and handling requirements as well as eroding profit margins. Recent changes in farming practices include the move away from stick culture to single seed culture, as the half-shell market demands a more uniformly shaped oyster. When selective breeding demonstrated that it could reduce time to market (50 g whole weight) by nearly a year out of an industry average of 3.5 years, the industry wanted to try hatchery technology. Although the industry had never used hatchery technology before, it purchased 10 million spat or 8% of its annual spat requirement from hatcheries in 2003-2004, the first year that they were made available to farmers. The industry also embraced the Australian Shellfish Quality Assurance Program, which requires that shellfish harvest areas be classified on the basis of a sanitary survey and the results of an ongoing strategic water-sampling programme. This programme ensures product safety for the consumers and helps to provide the industry with a long-term future.

scholarly journals Modeling Methane Emission from Wetlands in North-Eastern New South Wales, Australia Using Landsat ETM+

2010 ◽  
Vol 2 (5) ◽  
pp. 1378-1399 ◽  
Author(s):  
Clement E. Akumu ◽  
Sumith Pathirana ◽  
Serwan Baban ◽  
Daniel Bucher
Keyword(s):  
Methane Emission ◽  
New South ◽  
New South Wales ◽  
South Wales ◽  
North Eastern

On-site domestic wastewater treatment by reed bed in the moist subtropics

2001 ◽  
Vol 44 (11-12) ◽  
pp. 353-360 ◽  
Author(s):  
L. Davison ◽  
T. Headley ◽  
M. Edmonds
Keyword(s):  
New South ◽  
Domestic Wastewater ◽  
Moisture Loss ◽  
Reed Beds ◽  
Treatment Performance ◽  
South Wales ◽  
Domestic Wastewater Treatment ◽  
Australian State ◽  
North Eastern ◽  
Reed Bed

This paper summarises the results of studies on four subsurface flow wetlands (reed beds) located in the moist sub-tropical north eastern corner of the Australian state of New South Wales. The reed beds, which are subjected to a variety of effluent types, all have a gravel substrate planted with Phragmites australis. All four units were found to maintain satisfactory treatment performance year round. Mean removal efficiencies ranged from 56% to 90% (SS), 70% to 93% (BOD), 38% to 66% (TN), 87% to 99.8% (Faecal coliforms), and 42% to 70% (TP - with one seasonal result of 0% for the eight year old unit) for the four reed beds. After eight years in operation the oldest reed bed was showing signs of phosphorus saturation with outlet TP concentrations exceeding inlet concentrations on some occasions. The youngest reed bed studied appeared to be operating efficiently after five months. A summer water balance on one of the reed beds revealed an average crop factor of 1.6 and a moisture loss to atmosphere of 40% of influent flow. Treatment performance (particularly for TN and SS) was found to be negatively correlated with rainfall during one study. The paper discusses the implications of the above results for on-site system designers and regulators and identifies areas for further investigation.

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