Changes in relative abundance of sharks and rays on Australian South East Fishery trawl grounds after twenty years of fishing

2001 ◽  
Vol 52 (4) ◽  
pp. 549 ◽  
Author(s):  
K. J. Graham ◽  
N. L. Andrew ◽  
K. E. Hodgson
Keyword(s):  
New South ◽  
Early Years ◽  
Catch Rate ◽  
Depth Range ◽  
South Wales ◽  
Sampling Protocols ◽  
Species Groups ◽  
The Mean ◽  
Low Levels ◽  
Catch Rates

Upper continental slope trawling grounds (200–650 m depth) off New South Wales were surveyed with the same vessel and trawl gear and similar sampling protocols in 1976–77 (during the early years of commercial exploitation) and in 1996–97. The 1996–97 mean catch rate of sharks and rays, pooled for the main 15 species (or species groups), was ~20% of the 1976–77 mean. Individual catch rates were substantially lower in 1996–97 for 13 of the 15 species or species groups. The greatest decline was observed for dogsharks of the genus Centrophorus, which were most abundant in 1976–77 but rarely caught 20 years later. In contrast, 1996–97 catch rates of spiky dogshark (Squalus megalops) and, to a lesser extent, whitefin swell shark (Cephaloscyllium sp. A) were similar to those in 1976–77. Trawling during 1979–81 provided data for nine species, albeit not corrected for larger gear size, and the pooled mean catch rate for sharks and rays in the depth range 300–525 m was ~28% of the mean for 1976–77. The results suggest that the biomass of most species of sharks and rays declined rapidly as the fishery developed and is now at very low levels.

Spatial variation in soil organic carbon and nitrogen at two field sites under crop and pasture rotations in southern New South Wales, Australia

Soil Research ◽  
2018 ◽  
Vol 56 (8) ◽  
pp. 780 ◽  
Author(s):  
Mark Conyers ◽  
Beverley Orchard ◽  
Susan Orgill ◽  
Albert Oates ◽  
Graeme Poile ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Spatial Variation ◽  
New South ◽  
New South Wales ◽  
Wagga Wagga ◽  
Soil Cores ◽  
South Wales ◽  
Sampling Protocols ◽  
The Mean

Estimating the likely variance in soil organic carbon (OC) at the scale of farm fields or smaller monitoring areas is necessary for developing sampling protocols that allow temporal change to be detected. Given the relatively low anticipated soil OC sequestration rates (<0.5 Mg/ha.0.30 m/year) for dryland agriculture it is important that sampling strategies are designed to reduce any cumulative errors associated with measuring soil OC. The first purpose of this study was to evaluate the spatial variation in soil OC and nitrogen (N), in soil layers to 1.50 m depth at two monitoring sites (Wagga Wagga and Yerong Creek, 0.5 ha each) in southern New South Wales, Australia, where crop and pasture rotations are practiced. Four variogram models were tested (linear, spherical, Gaussian and exponential); however, no single model dominated across sites or depths for OC or N. At both sites, the range was smallest in surface soil, and on a scale suggesting that sowing rows (stubble) may dominate the pattern of spatial dependence, whereas the longer ranges appeared to be associated with horizon boundaries. The second purpose of the study was to obtain an estimate of the population mean with 1%, 5% and 10% levels of precision using the calculated variance. The number of soil cores required for a 1% precision in estimation of the mean soil OC or N was impractical at most depths (>500 per ha). About 30 soil cores per composite sample to 1.50 m depth, each core being at least 10 m apart, would ensure at least an average of 10% precision in the estimation of the mean soil OC at these two sites, which represent the agriculture of the region.

Spatial, seasonal and biological analysis of sharks caught in the New South Wales protective beach meshing programme

1994 ◽  
Vol 45 (7) ◽  
pp. 1087 ◽  
Author(s):  
M Krogh
Keyword(s):  
New South ◽  
New South Wales ◽  
Carcharodon Carcharias ◽  
Galeocerdo Cuvier ◽  
South Wales ◽  
Species Groups ◽  
Catch Rates ◽  
Regional Associations ◽  
High Catch ◽  
Carcharias Taurus

Data for the catches of sharks at each beach meshed in New South Wales are presented for the period from October 1972 to December 1990. High catch rates of sharks were observed at a number of these beaches. Comparison of the catches of sharks at each beach by means of hierarchical clustering and nonmetric multidimensional scaling revealed regional associations as well as some unusual relationships. Beaches at either end of each netted region (i.e. Newcastle, Sydney or Wollongong) tended to have higher catches than did beaches in the centre of each region. Hammerhead sharks (Sphyrna spp.) had significantly higher catch rates on long open beaches. Significantly higher catches of whaler (Carcharhinus spp.), white (Carcharodon carcharias), and tiger (Galeocerdo cuvier) sharks occurred when deeper water was closer to the beach. Limited biological and seasonal data are also presented for the 11 species or species groups: Sphyrna spp., Carcharhinus spp., Squatina austmlis, Heterodontus spp., Carcharodon carcharias, Galeocerdo cuvier, Carcharias taurus, Notorynchus cepedianus, Alopias spp., Isurus oxyrinchus and Orectolobus spp.

Genetic and environmental effects on a temperament score in beef cattle

1984 ◽  
Vol 35 (5) ◽  
pp. 723 ◽  
Author(s):  
H Hearnshaw ◽  
CA Morris
Keyword(s):  
Bos Taurus ◽  
New South ◽  
North Coast ◽  
The North ◽  
South Wales ◽  
Significant Difference ◽  
Medium Level ◽  
The Mean ◽  
Low Levels ◽  
The Difference

Temperament scores were taken on 8-month-old calves from five calf drops (1976-80) and over three sections of a large crossbreeding trial on the North Coast of New South Wales. A 0-5 scale was used, with lower values for quieter cattle. The heritability �s.e. of temperament score of Bos taurus calves (sired by Hereford, Simmental and Friesian bulls) was 0.03�0.28, and for B. indicus-sired calves (Brahman, Braford and Africander bulls) 0.46�0.37, and for all data combined 0.44�0.25. There was a significant difference (P < 0.01) between the mean score of Brahman-sired halfbred calves (1.96) and B. taurus-sired calves (1.05). The difference was halved to 0.45 points for quarterbred Brahman calves versus B. taurus calves, i.e. as expected for an additive trait. There were significant differences in temperament among calves sired by B. indicus bulls, but there were no significant differences amongst the B. taurus sire breeds. The repeatability (mean � s.e.) of operators' score of 701 weaner calves was 0.67�0.08. From temperament scores of 315 cows at weaning in 1981, an operator repeatability of 0.82�0.08 was obtained. Correlations of cow and calf score were not consistent, but averaged 0.18�0.04 from 547 records. The repeatability of scores taken at two separate times on 132 calves, was 0.43�0.09. The group given a medium level of nutrition had significantly higher temperament scores than those given high or low levels. Sex effects were not significant on scores at weaning. A log transformation of the data equalized the variance of scores of different breeds, but did not affect the conclusions.

How adolescents perceive that community-based exercise improves their well-being

2017 ◽  
Vol 25 (5) ◽  
pp. 456-459
Author(s):  
Kevin Rourke ◽  
Coralie J Wilson
Keyword(s):  
New South ◽  
Well Being ◽  
Parental Consent ◽  
Community Based ◽  
Team Games ◽  
South Wales ◽  
Perceived Benefit ◽  
The Mean ◽  
Mental Well Being ◽  
Energy Survey

Objectives: To determine if adolescents perceive community-based exercise as beneficial to their well-being and in what ways. Methods: A New South Wales Police Citizens Youth Club ran a four-week fitness course. The classes involved: 1) sports including basketball and soccer, 2) non-contact boxing drills, and 3) games, both team games such as dodgeball and non-team games such as line tag. Parental consent to offer a survey at the completion of the course was requested during registration. The survey was the Warwick Edinburgh Mental Well-being Scale; it was minimally modified to measure perceived benefit to mental well-being instead of actual benefit. Results: Thirty-one high school adolescents, ages 13–18, completed the survey. As a group, participants reported that they believed their well-being had improved after the course. The mean score for each survey item showed an improvement in every area of mental well-being for this sample of adolescents. Thirty-two per cent of adolescents reported having less energy. Survey scores indicated a statistically significant improvement in perceived well-being ( p<0.0001). Conclusions: The results of this study suggest that four weeks of community-based exercise improves perceived mental well-being in adolescent participants.

The breeding behaviour of the endangered regent honeyeater, Xanthomyza phrygia, near Armidale, New South Wales

1998 ◽  
Vol 46 (2) ◽  
pp. 153 ◽  
Author(s):  
Damon L. Oliver
Keyword(s):  
New South ◽  
New South Wales ◽  
Population Level ◽  
Similar Rate ◽  
Nest Construction ◽  
Aggressive Interactions ◽  
Breeding Behaviour ◽  
South Wales ◽  
The Mean ◽  
Breeding Seasons

The regent honeyea ter, Xanthomyza phrygia, is an endangered woodland bird whose range and population size have decreased in the last thirty years. Suggested reasons for this decline include abnormal breeding behaviour, poor reproductive output, and excessive inter- and intra-specific aggression. This study investigated the breeding behaviour and aggressive interactions of regent honeyeaters during the nest construction, incubation, nestling, and fledgling stages in two consecutive breeding seasons in the Bundarra–Barraba region near Armidale, New South Wales. The female was entirely responsible for nest construction and incubation, which is typical of many honeyeaters. Both parents fed the nestlings, and at a similar rate, although only the female brooded chicks on the nest. Both parents fed the fledglings. The mean frequency at which nestlings (23 times per hour) and fledglings (29 times per hour) were fed is the highest published rate of any non-cooperative honeyeater. Breeding males were involved in significantly more aggressive interactions with conspecifics and other nectarivores than were females, although the overall percentage of day-time spent in aggression for both sexes was low (2.5%). It appears that abnormal breeding behaviour, poor reproductive effort, or excessive aggression are not experienced by this species in northern New South Wales, and that other factors are likely to be responsible for its current low population level.

The residual effect of phosphorus on soil fertility and pasture development on acid soils

1951 ◽  
Vol 2 (4) ◽  
pp. 377 ◽  
Author(s):  
AJ Anderson ◽  
KD McLachlan
Keyword(s):  
Soil Fertility ◽  
New South ◽  
Total Yield ◽  
Acid Soils ◽  
Residual Effect ◽  
Early Years ◽  
High Fertility ◽  
South Wales ◽  
Phosphate Fixation ◽  
Nitrogen Demand

A study was made of the residual effect of superphosphate applied to pasture on acid soils on the Southern Tablelands of New South Wales. The effect of the superphosphate on the development of clover and subsequent changes in soil fertility and development of grass was examined. Only a limited proportion of the phosphorus applied was taken up by the pasture over the period of the experiments, but the evidence obtained suggests that this cannot be ascribed merely to phosphate fixation in the soil. The residual phosphorus was little, if any, less effective than current dressings over a number of years. The total yield of pasture was dependent almost entirely on the amount of superphosphate applied, and frequency of application had little or no effect on the total yield. A single dose at the commencement of the trials was as effective in increasing the total yield and the uptake of phosphorus as were annual dressings. High fertility and grass dominance were achieved by heavy annual dressings of superphosphate or by application of the bulk of the phosphorus in the early years. Lighter annual dressings resulted in clover dominance. Some advantages of heavier, less frequent application of superphosphate are discussed. Competition for phosphorus was an important factor in suppression of the clover by the grass. Evidence was presented in support of a hypothesis that grass or clover dominance is dependent both upon the vigour and fertility requirements of the species and upon the relation between the nitrogen demand of the pasture unit and the soil nitrogen status.

Characterisation of naturalised strains of Trifolium subterraneum var. brachycalycinum cv. Clare in northern New South Wales

1994 ◽  
Vol 34 (1) ◽  
pp. 33 ◽  
Author(s):  
GM Lodge
Keyword(s):  
Seed Weight ◽  
New South ◽  
New South Wales ◽  
Trifolium Subterraneum ◽  
Summer Rainfall ◽  
Median Number ◽  
South Wales ◽  
The Mean ◽  
Floral Characters ◽  
Number Of Seeds

Burrs were collected from paddocks on 3 properties in northern New South Wales where the age of the Trifolium subterraneum var. brachycalycinum cv. Clare swards varied from 19 to 28 years. At 1 site burrs were also sampled from swards sown 2 and 10 years previously. Twenty seedlings from these burrs and 20 plants of certified cv. Clare were grown as spaced plants in a nursery. These were assessed for vegetative and floral characters, flowering time, number of seeds per burr, seed weight, and percentage hardseed after storage at 25/25�C for 6 months and 25/45�C for a further 6 months. For most plants the mean number of days from sowing to first flower was similar to that of Clare. Compared with the naturalised strains, Clare had the lowest (P<0.05) mean number of seeds per burr: about 25% below the mean of the strains (2.7 seeds per burr). While the lowest mean seed weights of the strains were not significantly different from those of Clare, the seed weights of plants from 3 sites were higher (P<0.05) than those of Clare. After storage for either 6 or 12 months, hardseed levels were also lowest (P<0.05) for Clare. Plants from the 2-year-old sward had the same median number of seeds per burr (2.0) as Clare. As sward age increased, the median number of seeds per burr increased to 2.8. Hardseed percentages were lowest for plants of Clare and for those from the 2-year-old sward after 6 months, and for Clare after 12 months. These studies indicated the presence of divergent strains in old swards of Clare in a summer rainfall environment. Natural selection among variability within Clare is the most likely reason for the development of these strains in an environment marginal for the long-term persistence of this softseeded cultivar. Although strains had the same vegetative and floral markings as Clare, differences in ecologically important characters such as number of seeds per burr, seed weight, and hardseededness may result in plants that are better adapted to the environment in which they evolved. From these studies 23 plants of T. subterraneum var. brachycalycinum were selected for further evaluation.

Effect of prolonged undernutrition on the recovery and reproductive performance of maiden Merino ewes

1967 ◽  
Vol 7 (24) ◽  
pp. 7 ◽  
Author(s):  
P McInnes ◽  
TJ Grainger ◽  
MD Smith
Keyword(s):  
Body Weight ◽  
Reproductive Performance ◽  
New South ◽  
New South Wales ◽  
The Other ◽  
First Year ◽  
Treatment Groups ◽  
South Wales ◽  
Feeding Trials ◽  
The Mean

Data are presented on the recovery and reproductive performance of 2 1/2-year-old maiden Merino ewes after a prolonged period of undernutrition. The 217 sheep had been hand-fed on a submaintenance ration in pen feeding trials at Glenfield, New South Wales. During the seven months of the trials they had lost 6 kg (28 to 22 kg) body weight. They were transported to Condobolin in south-western New South Wales, divided into two treatment groups and run on good quality pastures. One group was joined immediately (May 1959) and again ten months later, and the other group was mated after six months at Condobolin (in October 1959) and again 12 months later. The ewes recovered rapidly. The mean weight of both groups had reached 30 kg within six weeks and 40 kg within six months. In the first year 73 of the 100 May-mated ewes bore lambs, but only 38 of these lambs were weaned. Ewes bearing lambs had a higher body weight at the start of joining and gained more during joining than the barren ewes. At the other three joinings (October 1959, May 1960, October 1960) lambing percentage was from 86-89 and weaning percentage from 62-69-both normal for the district. The proportion of twin lambs (3-6 per cent) was low. Wool weight in 1959 was not affected by time of mating or by pregnancy.

Survey of paddock size and stock water supplies in the Western Riverina District of New South Wales.

1978 ◽  
Vol 1 (2) ◽  
pp. 167
Author(s):  
VR Squires
Keyword(s):  
Fresh Water ◽  
Vegetation Type ◽  
New South ◽  
New South Wales ◽  
Current Level ◽  
Vegetation Types ◽  
Temporary Waters ◽  
South Wales ◽  
Saline Waters ◽  
The Mean

In order to assess the current level of stock watering facilities on pastoral properties within the western Riverina district of New South Wales and to relate this information to paddock size and vegetation type, large of areas of land (785,000 ha) within the region were surveyed. Paddock boundaries and the location of watering points were plotted. Watering points were classified as to type. Three broad vegetation types were represented: chenopod shrublands (Atriplex and Maireana spp.) degraded grasslands (Stipal Danthonia spp.), and mallee woodlands (Eucalyptus socinlis F. Meull., E, oleosa, F. Meull.) Size of paddocks was related to the dominant vegetation type. On the degraded grasslands in the eastern part of the study area the mean paddock size was 746 ha; on the chenopod shrublands it was 780 ha, and in the Malleedominated areas it was 1,553 ha. The number of permanent watering points per paddock varied from one to four. Less than half the paddocks (43%) had fresh water available as well as saline waters from sub-artesian bores. Almost half the paddocks (47%) were so large, or the watering points so positioned, that the sheep would need to walk more than 3 km to reach the most remote parts of the paddock when temporary waters had dried up. Overall 18% of the land in the non- mallee areas was more than 3 km from permanent water. Therefore the majority of the land could be used in all seasons. Generally the central and northern Riverina district is adequately watered. It would be uneconomic to supply permanent water in the mallee woodlands. In some paddocks in the chenopod dominated area extra watering points may be justified.

The effects of grazing and season on the stability of Chloris Spp. (Windmill grasses) in natural pasture at Trangie, New South Wales.

1978 ◽  
Vol 1 (2) ◽  
pp. 106 ◽  
Author(s):  
DL Michalk ◽  
PK Herbert
Keyword(s):  
New South ◽  
New South Wales ◽  
Grazing Pressure ◽  
Basal Diameter ◽  
South Wales ◽  
Natural Pasture ◽  
Mean Diameter ◽  
The Mean ◽  
The Stability ◽  
Stocking Rates

A study of the density and basal diameter of Chloris acicularis Lindl. (syn. Enteropogon acicularis (LindlJLazar. - curly windmill grass) and C. truncata R. Br. (windmill grass) was made at two stocking rates over a period of eight years. The propor- tion of ground covered by these Chloris species varied widely with season, and to a lesser extent with grazing pressure. The density of both species increased in good seasons, while the mean diameter decreased because of the number of new seedlings. Although C. truncata seedlings were more numerous in good seasons, they did not survive as well as did C. acicularis seedlings during prolonged dry periods.

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