Demography of a yellow-footed rock-wallaby Petrogale xanthopus colony in the threatened New South Wales sub-population.

2006 ◽  
Vol 28 (2) ◽  
pp. 215 ◽  
Author(s):  
A. Sharp ◽  
M. Norton ◽  
A. Marks
Keyword(s):  
New South ◽  
New South Wales ◽  
Survival Rates ◽  
Adult Survival ◽  
Juvenile Survival ◽  
Management Actions ◽  
South Wales ◽  
Low Levels ◽  
Reproductive Rates ◽  
Substantial Decline

The remnant New South Wales (NSW) yellow-footed rock-wallaby (Petrogale xanthopus) population underwent a substantial decline between 1985 and 1992 and remained at dangerously low levels until 1995. To determine the processes underlying this decline, a population study was conducted at one colony, between winter 1995 and winter 1998. The colony was observed to remain relatively constant in size, consisting of between 12 or 13 individuals throughout the study. Reproductive rates were found to be relatively high. Both reproduction and pouch young survival were comparable with those reported for other P. xanthopus colonies, while adult survival rates were higher than those noted in other studies. Because population size remained constant during the study and adult survivorship was consistently high, this suggested that juvenile recruitment into the colony was low. Such low levels of recruitment may have had a substantive role in the slow decline of the entire NSW P. xanthopus population. The results of this study suggest that any management actions undertaken in the NSW P. xanthopus population should focus on increasing juvenile survival rates. Further research is required to determine whether juvenile survival is constrained by predation or competition with other herbivores.

The influence of various factors on survival rate to weaning of Merino lambs. I. Sex, strain, location, and age of ewe for single-born lambs

1965 ◽  
Vol 16 (6) ◽  
pp. 981 ◽  
Author(s):  
J Lax ◽  
Turner H Newton
Keyword(s):  
Survival Rate ◽  
New South ◽  
Strong Association ◽  
New South Wales ◽  
Survival Rates ◽  
Age Groups ◽  
Strain Differences ◽  
Marked Rise ◽  
South Wales ◽  
Improved Pasture

The influence of sex, strain, location, and age of ewe on survival rate to weaning of single-born Merino lambs has been examined in two sets of data: the strain trial, involving five strains run without selection at each of three locations (Cunnamulla, Qld.; Armidale, on the northern tablelands of New South Wales; Deniliquin, in the Riverina area of New South Wales), with six age groups of ewes; and the same five strains later included in selection groups at Armidale with seven age groups of ewes. The strain trial at Armidale ran mainly on native, and the selection groups mainly on improved pastures. Female lambs had a higher survival rate than either castrated or entire males, the differences in lambs weaned per lamb born being 0.03 and 0.04 respectively. No strain differences could be regarded as statistically significant, and neither could the strain x location interaction in the strain trial. Mean survival rates for the strains ranged from 0.673 to 0.786 on the Armidale native and from 0.802 to 0.850 on the Armidale improved pasture, from 0.746 to 0.859 at Cunnamulla, and from 0.838 to 0.894 at Deniliquin. The strains did not rank consistently in the same order. Location had a marked effect on survival rate, the means being 0.744 for the native and 0.824 for the improved pasture at Armidale, 0.810 at Cunnamulla, and 0.868 at Deniliquin. Age of ewe had a marked influence in the poorest environment (Armidale native pasture), survival rate rising with age and later falling sharply. The effect was less marked in the intermediate environments (Armidale improved pasture and Cunnamulla) and negligible at Deniliquin. The patterns at Cunnamulla and Deniliquin are confirmed by data from other experiments on these stations. Survival rate is one component of number of lambs weaned. The other component, number of lambs born, has a higher mean value at Deniliquin than Cunnamulla, but shows a strong association with age of ewe in both environments. Number of lambs born responds rapidly to selection, but no information is yet available concerning the likely response in survival rate. If improvement in environment can raise the survival rate, particularly in the youngest and oldest ewes, then selection for number of lambs born, combined with improved environment, should lead to a marked rise in the number of lambs weaned.

scholarly journals Cyclic dynamics of snowshoe hares on a small island in the Yukon

2002 ◽  
Vol 80 (8) ◽  
pp. 1442-1450 ◽  
Author(s):  
Charles J Krebs ◽  
Todd N Zimmerling ◽  
Claire Jardine ◽  
Kim A Trostel ◽  
Alice J Kenney ◽  
...  
Keyword(s):  
Population Decline ◽  
Survival Rates ◽  
Ground Squirrels ◽  
Adult Survival ◽  
Small Island ◽  
Juvenile Survival ◽  
Lower Amplitude ◽  
Arctic Ground Squirrels ◽  
Reproductive Rates ◽  
Survival Differences

Snowshoe hare (Lepus americanus) populations were monitored from 1977 to 2001 on Jacquot Island (5 km2) in Kluane Lake, southwestern Yukon, and on nearby mainland sites. Jacquot Island hares averaged twice the density of mainland control populations and, although they show 10-year cycles, fluctuate with much lower amplitude than mainland populations. Three separate intensive studies over 6 years attempted to determine what caused these differences. We tested two hypotheses to explain the dynamics. Reproductive rates of hares were similar on Jacquot Island and the mainland. Adult survival rates were higher on the island in most years, with the exception of years of population decline. Juvenile survival rates from 0 to 30 days of life were much higher on the island than on the mainland except for decline summers. The adult- and juvenile-survival differences between the island and the mainland were explained most consistently by predation. Improved survival on the island is correlated with a reduction in the numbers and types of predators found on Jacquot Island compared with the mainland. In particular, red squirrels were rare on Jacquot Island, arctic ground squirrels were absent, and the larger predators, like lynx and great-horned owls, were sporadic in occurrence on this small island.

Observations on the effects of rabbit calicivirus disease on low and medium density rabbit populations in western New South Wales

2001 ◽  
Vol 23 (2) ◽  
pp. 194 ◽  
Author(s):  
Andy Sharp ◽  
Kerry Holmes ◽  
Melinda Norton ◽  
Adam Marks
Keyword(s):  
Arid Zone ◽  
New South ◽  
New South Wales ◽  
Winter Period ◽  
Low Density ◽  
Medium Density ◽  
Management Actions ◽  
South Wales ◽  
Positive Growth ◽  
Density Population

Between winter 1995 and winter 1998, seasonal spotlight counts for rabbits were conducted along three transects in western New South Wales. Rabbit Calicivirus (RCV) arrived at the study site in spring 1996 and had an immediate marked effect on rabbit densities. Prior to the advent of Rabbit Calicivirus Disease (RCD), rabbit abundance followed the expected annual pattern of positive growth during the winter to summer period and negligible or negative growth during the summer to winter period. With the arrival of RCV, rabbit abundance was observed to decline by 47% and 75% within low density populations and by 84% within a medium density population. In the subsequent 21 months, the low density populations returned to levels approximating those prior to the arrival of RCV. In contrast, rabbit abundance within the medium density population remained at consistently lowered levels. These data suggest that RCD will have a minimal effect on semi-arid zone rabbit populations below a density of 0.4/ha and that additional management actions will be required to further reduce rabbit abundances.

Seedling emergence and survival of annual pasture legumes in northern New South Wales

1996 ◽  
Vol 47 (4) ◽  
pp. 559 ◽  
Author(s):  
GM Lodge
Keyword(s):  
New South ◽  
Seedling Emergence ◽  
New South Wales ◽  
Survival Rates ◽  
Trifolium Subterraneum ◽  
Survival Curves ◽  
Vicia Villosa ◽  
Pasture Legumes ◽  
South Wales ◽  
Seedling Emergence And Survival

Seedling emergence and survival of 15 annual pasture legumes was studied in the field at Tamworth, northern New South Wales. Emergence was measured in permanent quadrats (0.09 m2) in covered and uncovered areas approximately every 15 days from 30 November 1983 to 30 November 1984. Survival of seedlings was estimated from 15 December 1983 to 31 August 1984, before plants senesced. Emergence was generally highest in summer and autumn following seed set and lowest in winter and spring. Two legumes, Medicago scutellata cv. Sava and Trifolium subterraneum cv. Seaton Park, had high emergence in winter (mid July). Total seedling emergence was highest ( P < 0.05) in covered areas of cv. Seaton Park and uncovered areas of T. hirtum cv. Hykon. All T. subterraneum cultivars, M. minima, Astragalus hamosus cv. Ioman, Vicia villosa cv. Namoi, and M. truncatula cv. Paraggio had higher total emergence in covered compared with uncovered areas. In contrast, total emergence of M. aculeata, M. truncatula cv. Jemalong, Sava, and Hykon was lowest in covered areas. Cover had little effect on the total emergence of M. truncatula cv. Sephi and T. glomeratum. Of the 7700 individual seedlings marked from November 1983 to August 1984, a mean of only 31% (covered) and 41% (uncovered) survived until 31 August 1984. For each emergence time, highest ( P < 0.05) survival rate coincided with the highest (P < 0.05) number of emerged seedlings in 4 of the legumes in covered areas (cv. Namoi, 31 January; cv. Ioman, 31 March; cv. Hykon, 15 April; cv. Sava, 15 July; Table 4) and 9 in uncovered areas (cvv. Nungarin, Seaton Park, and Namoi, 31 January; M. aculeata and cv. Sephi, 28 February; cvv. Jemalong and Ioman, 31 March; T. glomeratum, 15 April; cv. Sava, 15 July). In all other legumes there was no optimum time for emergence, since the highest (P < 0.05) survival rates were associated with seedling survivals <50%. Generally, survival curves with a mortality constant rather than a mortality rate were a better fit ( P < 0.05) for most legumes and times. This implied that these survival curves were determined at the time of recruitment, and declined at a constant rate, despite below-average post-emergence rainfall in May-June. Low rates of survival at times of highest ( P < 0.05) emergence indicated that there may have been some density-dependent regulation in some of the legumes.

Land management within capability: a new scheme to guide sustainable land management in New South Wales, Australia

Soil Research ◽  
2015 ◽  
Vol 53 (6) ◽  
pp. 683 ◽  
Author(s):  
Jonathan M. Gray ◽  
Greg A. Chapman ◽  
Brian W. Murphy
Keyword(s):  
Land Management ◽  
Land Degradation ◽  
Management Practices ◽  
New South ◽  
New South Wales ◽  
Sustainable Land Management ◽  
Management Actions ◽  
Evaluation Scheme ◽  
Management Regime ◽  
South Wales

A new evaluation scheme, land management within capability (LMwC), used to guide sustainable land management in New South Wales (NSW), is presented. The scheme semi-quantitatively categorises the potential impacts of specific land-management actions and compares these with the inherent physical capability of the land in relation to a range of land-degradation hazards. This leads to the derivation of LMwC indices, which signify the sustainability of land-management practices at the scale of individual sites up to broader regions. The LMwC scheme can be used to identify lands at greatest risk from various land-degradation hazards. It can help to guide natural resource agencies at local, regional and state levels to target priorities and promote sustainable land management across their lands. Few other schemes that assess the sustainability of a given land-management regime in a semi-quantitative yet pragmatic manner are found in the literature. The scheme has particular application for regional soil-monitoring programs and it was applied in such a program over NSW in 2008–09. The results suggested that the hazards most poorly managed across the state are wind erosion, soil acidification and soil organic carbon decline. The LMwC scheme, or at least its underlying concepts, could be readily applied to other jurisdictions.

The prevalence of lice (Bovicola ovis) in sheep flocks on the central and southern Tablelands of New South Wales

2012 ◽  
Vol 52 (7) ◽  
pp. 659 ◽  
Author(s):  
S. Popp ◽  
J. Eppleston ◽  
B. R. Watt ◽  
S. Mansfield ◽  
R. D. Bush
Keyword(s):  
Visual Detection ◽  
New South ◽  
New South Wales ◽  
Prevalence Estimate ◽  
Moderate Increase ◽  
True Prevalence ◽  
Apparent Prevalence ◽  
South Wales ◽  
Low Levels ◽  
Livestock Health

In response to suggestions that the incidence of louse infestations in New South Wales has increased markedly, a survey of 173 producers was conducted in the Tablelands Livestock Health and Pest Authority region using visual detection and a questionnaire to document retrospective lice history. An estimated apparent prevalence of 16.5% is a moderate increase from the 10% reported in 2004. On a subset of the surveyed sheep flocks sheep, lice-specific immunoassay conducted by the New South Wales Department of Primary Industries were used to detect low levels of infestation that were not identified by visual detection. This provided a true prevalence estimate of 30%. These results will be used to promote improved control and preventative strategies.

Germination, emergence, growth, ecotypes and control of Carex appressa R. Br. (tussock sedge)

2002 ◽  
Vol 42 (1) ◽  
pp. 27 ◽  
Author(s):  
M. H. Campbell ◽  
H. I. Nicol
Keyword(s):  
New South ◽  
New South Wales ◽  
Primary Root ◽  
Germination Percentage ◽  
Pasture Production ◽  
South Wales ◽  
Heavy Grazing ◽  
Substantial Decline ◽  
Almost All ◽  
And Control

Germination of seeds of Carex appressa R.Br. (tussock sedge) collected in 1989 and 1990 from Bigga, Boorowa and Kerrs Creek, New South Wales, Australia, stored in a laboratory and germinated annually in 45-day tests, declined from an initial 75–90% in year 1 to 0.5–14% in years 10 and 11. The germination of seeds collected from Bigga and Boorowa in 1991 declined from 90–91% in year 1 to 12–61% in year 9. This decline was best described by generalised logistic curves (Bigga) and exponential curves (Boorowa). Most seeds that failed to germinate were shown to be non-viable by the tetrazolium test. Rate of germination declined with seed age, so that days for 50% of final germination percentage increased from 8 days for 1 year-old seeds to >40 days for 11-year-old seeds. Of 8–11-year-old seeds that germinated between days 45 and 140, 62–70% had deformed seedlings. Germination of seeds buried in the soil for 0.5–2.7 years was lower than that of the same seed stored in the laboratory. Germination of seeds buried at 5 mm (19%) was lower than that of the same seeds buried at 40 mm (50%). Almost all the decline in germination occurred in the first 6 months of burial. Increased depth of sowing reduced emergence (%), height of the shoot and length of the primary root and increased the time taken for emergence and length of the mesocotyl. The maximum depth C. appressa seedlings could emerge from was 44 mm. Growth of C. appressa seedlings was slower than that of pasture species and responded to nitrogen and nitrogen + phosphorus and/or sulfur but not to phosphorus and/or sulfur. Differences were recorded in the morphology of plants grown from seeds collected from various locations and grown in the 1 environment at Orange, New South Wales. Control of C. appressa was achieved by draining, slashing and removing litter, applying glyphosate, surface-sowing pasture species and topdressing with superphosphate. Five years after sowing, the foliage cover of legumes and grasses on the best treatment was 71% and that of C. appressa 2%, a substantial decline from the original 81% infestation. The best technique for control of C. appressa on infested creek flats suitable for pasture production would be to drain, plough and bury seeds below 44 mm and then sow pastures with superphosphate. Where ploughing is not possible, drainage, burning to remove foliage, spraying with glyphosate and surface-sowing pastures with superphosphate would be successful. In both situations, long-term control can be achieved by heavy grazing for short periods only when the soil is firm and removing re-infesting plants by annual spot spraying.

Low levels of bycatch from estuarine prawn seining in New South Wales, Australia

2003 ◽  
Vol 64 (1) ◽  
pp. 37-54 ◽  
Author(s):  
Charles A Gray ◽  
Steven J Kennelly ◽  
Kate E Hodgson
Keyword(s):  
New South ◽  
New South Wales ◽  
South Wales ◽  
Low Levels

scholarly journals COVID-19 Australia: Epidemiology Report 31: Fortnightly reporting period ending 6 December 2020

2020 ◽  
Vol 44 ◽  
Author(s):  
Keyword(s):  
Sore Throat ◽  
New South ◽  
New South Wales ◽  
Surveillance Period ◽  
Runny Nose ◽  
Daily Average ◽  
Unknown Source ◽  
South Wales ◽  
Case Count ◽  
Low Levels

Nationally, COVID-19 notifications remained at low levels this fortnight. Testing rates also decreased during the surveillance period. The daily average number of cases was eight compared to an average of 11 cases for the previous fortnight. There were 109 cases of COVID-19 and no deaths this fortnight, bringing the cumulative case count to 28,049 and 908 deaths. New South Wales reported the highest proportion of cases again this fortnight (54%; 59/109), with the majority of these acquired overseas (97%; 57/59). Locally-acquired cases accounted for 5% (5/109) of all cases reported this fortnight, with one of these from an unknown source. FluTracking data indicated that 47% of people in the community with ‘fever and cough’ and 19% of those with ‘runny nose and sore throat’ were tested for SARS-CoV-2, which was a decrease from the previous reporting period. Testing rates decreased to 9.3 tests per 1,000 population per week during this reporting period, representing a 29% decrease in fortnightly tests conducted compared to the last reporting period. The overall positivity rate for the reporting period remains at 0.03%.

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