The New South Wales Tiger Flathead Neoplatycephalus macrodon (Ogilby). II. The Age Compositon of the Commercial Catch, Overfishing of the Stocks, and Suggested Conservation

1952 ◽  
Vol 3 (1) ◽  
pp. 1 ◽  
Author(s):  
WS Fairbridge

The commercial flathead catch is analysed into its component age-groups. The results are expressed in numbers and weight of each age-group caught in each month. The results indicate an absence of natural fluctuations in abundance of the year-groups during the series of years covered. The post-war decline in the catch of flathead is discussed in the light of this analysis. The catch has fallen from 5,700,000 lb. in 1944–45 to 2,100,000 lb. in 1948–49. The catch of flathead for a period between the wars is estimated at over 10,000,000 lb. per year. The stock of flathead has thus shown a failure to recover during the war-time rest, as well as a sudden fall with the inception of heavy fishing of recent years. Possible reasons for these changes in the flathead stock are discussed. It is suggested that the numbers of recruits are limited by the numbers of spawning adults. The results obtained from this work are fuller, but in entire agreement with those of the earlier paper on the trawlfishery as a xvliole. The adoption of conservation measures is urged. The trawlfishery is now dependent on two hitherto discarded species of poorer quality than the flathead, and the better of these is already showing a reduced catch per unit effort of fishing. The most important conservation measure is that suggested in the earlier paper — a reduction of the fleet to the equivalent of 13 trawlers. It is regarded as probable that if this step is not taken, the annual trawlfish catch will continue to decline. Closure of the Botany fishing ground is suggested as a further, but not an alternative, measure.

2010 ◽  
Vol 139 (5) ◽  
pp. 658-665 ◽  
Author(s):  
A. JARDINE ◽  
S. J. CONATY ◽  
H. VALLY

SUMMARYRates of herpes zoster (HZ) hospitalizations, antiviral prescriptions, and New South Wales emergency-department presentations for age groups <20, 20–39, 40–59 and ⩾60 years were investigated. Trends were analysed using Poisson regression to determine if rates increased following funding of varicella immunization in Australia in November 2005. The regression analysis revealed significantly increasing trends of between 2% and 6% per year in both antiviral prescriptions and emergency-department presentations in all except the <20 years age group. When considered together, the differential changes in rates observed by age group provides preliminary evidence to indicate that HZ incidence is increasing in adults aged >20 years. However, it is not possible to attribute the increasing trends in HZ observed directly to the varicella immunization programme, and continued monitoring and analyses of data for a longer duration, both pre- and post-vaccine introduction, is required.


2008 ◽  
Vol 32 (3) ◽  
pp. 528 ◽  
Author(s):  
Neill Jones ◽  
Greg Hardes ◽  
Stephen Ryan ◽  
Jennifer Sheehan ◽  
Cathryn Cox ◽  
...  

Objectives: To describe the statewide projections of acute inpatient activity in New South Wales. Methods: Data on acute inpatient activity in NSW for the period 1998?1999 to 2003?04 were derived from the Admitted Patient Data Collection. Regression analysis was used to project trends in utilisation and length of stay by age group, clinical specialty groups and stay type (day-only and overnight). The projected separation rates and length of stay were subject to clinical review. Projected separation rates (by age group, clinical speciality and stay type) were applied to NSW population projections to derive the projected number of separations. Bed-days were calculated by applying projected overnight average length of stay. Results: Total acute inpatient activity in NSW public hospitals is projected to increase from around 1.05 million separations in 2004 to around 1.3 million separations by 2017 (24%). Same-day separations are projected to increase from around 368 000 to around 514 000 (40%). Overnight separations are projected to rise from around 690 000 in 2003?04 to around 798 000 in 2016?17 (18%). Overnight bed-days are projected to increase from around 3.7 million in 2003?04 to around 4.1 million bed-days in 2017 (12%). Differences across age groups and clinical specialties are also evident from the modelling.


1955 ◽  
Vol 6 (2) ◽  
pp. 165 ◽  
Author(s):  
TW Houston

The past course of the New South Wales mixed trawlfishery is reviewed mainly on the basis of the available catch and fishing effort statistics. The size composition of tiger flathead landings from 1946-47 to 1953-54, and the age composition for certain post-war years, are analysed in conjunction with catch per unit effort data. The results suggest that 1943-44, 1944-45, 1947-48, and 1948-49 were relatively poor brood years, and 1945-46 and 1946-47 relatively good. The fluctuations in availability of tiger flathead (Neoplatycephalus macrodon (Ogilby) ) are accounted for after making certain valid assumptions. It is considered probable that the unexpectedly low catches of tiger flathead in the immediate post-war years were due to inefficiency of the few steam trawlers then working, and that Danish seiners were unable to exploit fully the available V+ and higher age-group fish. An examination of the present situation indicates that the New South Wales stock of tiger flathead is at a low level and is likely to reach even lower levels in the future if fishing intensity remains as high as in 1953-54. An improvement of the existing catch per unit effort would be expected if fishing intensity was reduced to the level of the middle nineteen-thirties (i.e. approx. 3500 trawler-tons) . Other regulative measures would need to be introduced to bring about an improvement in the annual catch of tiger flathead. These measures should aim at ensuring a more favourable weight-length relation.


2018 ◽  
Vol 58 (8) ◽  
pp. 1470
Author(s):  
J. S. Richards ◽  
M. A. Sladek ◽  
G. J. Lee

Reproduction is an important driver of profitability in commercial sheep flocks. Historically, Merino flocks have been run with a fixed age structure, ignoring individual merit and casting for age at a specific age. More recently, research has focussed on utilising the variation within age groups by keeping productive older ewes longer and culling less productive ewes earlier. Previous studies have also examined the effect of age on reproduction and the impact of reproduction status on productivity, but little research has been conducted on cumulative effects of reproductive performance on later productivity, reproduction and health. The present study examined the impact of higher lifetime reproduction on other key production and fitness traits in older ewes run under commercial conditions. Data were collected from two commercial wool-producing properties in the South West Slopes and the Central West Plains of New South Wales during 2009–2011. Reproduction, fleece measurements, bodyweight and condition and dental health were recorded during the study. The results showed that age had a bigger effect on productivity and dental health than did cumulative lifetime reproduction. Environment and genetics determined the level of impact, with minimal loss in productivity from increased age of animals occurring in the South West Slopes flock, whereas the Central West Plains flock would appear to require closer monitoring of productivity as ewes aged. The data collected did not allow separation of the genetic and environmental influences within the study. Retaining animals with a higher reproductive performance past normal culling age does not necessarily result in reduction of productivity or ewe health, but this must be monitored.


1965 ◽  
Vol 16 (6) ◽  
pp. 981 ◽  
Author(s):  
J Lax ◽  
Turner H Newton

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.


1968 ◽  
Vol 8 (33) ◽  
pp. 425 ◽  
Author(s):  
EJ Sparke ◽  
DR Lamond

This paper reports an experiment examining the effect of age and protein supplementation on growth and fertility of Shorthorn-Devon cross heifers grazing natural pastures in the summer rainfall, subtropical environment of the Upper Clarence valley, north-eastern New South Wales. Heifers born over the period October to January 1963-64 were weaned in June 1964 and allotted at random within age groups (by month of birth) to a supplemented or non-supplemented treatment. The supplemented heifers were given linseed meal during the dry winter period each year from 1964 to 1966 inclusive (May-June to September-October). They were weighed each month and joined with bulls in the early summer of 1965 (2 years) and 1966 (3 years). They were examined for pregnancy in the autumn, and their calves were identified at birth. Supplemented heifers gained weight throughout and non-supplemented heifers generally lost weight in the winter periods. At two years fertility was closely related to liveweight at joining in supplemented heifers, but not in others. Heifers born in January gave the poorest reproductive performance, as the two supplemented ones that became pregnant in 1965 died at calving, and two-thirds of the non-supplemented ones were still empty after joining as 3-year-olds. The advantage of high 2-year-old fertility gained by heifers born in October and November, due to their greater size at joining, was partly offset by low fertility when lactating the following year. It is concluded that a decision as to whether a heifer should be supplemented during a period of nutritional stress prior to joining ought to be based on the probability of her reaching a prescribed target weight at joining as a result of receiving the supplement. The target weight for lactating heifers was at least 100 Ib higher than for dry hdfers. The results also indicate specific areas for further research.


2017 ◽  
Vol 3 (3) ◽  
pp. 292-321
Author(s):  
Lynne Horiuchi ◽  
Anoma Pieris

This article compares two former Pacific War incarceration histories in the us and Australia, inquiring how their narratives of confinement and redress might be interpreted spatially and materially, and how these sensibilities are incorporated into contemporary heritage strategies including, in these examples, through Japanese garden designs. At the Manzanar Historic Site in California, the efforts of several generations advocating for civil rights and preservation of the Manzanar Relocation Center have overlapped with the National Park Service’s efforts to fulfil its federal mandates to preserve and restore the historic site. Conversely at Cowra, New South Wales, these histories are interwoven with post-war commemorative spaces, aimed at drawing visitors to former incarceration sites and encouraging contemplation of these difficult histories. This article analyses their complex creative processes and interpretive strategies as useful for drawing these isolated national stories into broader global interrogations of their significance.


1963 ◽  
Vol 11 (3) ◽  
pp. 290 ◽  
Author(s):  
PD Dwyer

In M. s. blepotis, of north-eastern New South Wales, the annual moult occurs during the summer and early autumn and lasts about 14.5 weeks. Yearlings having their first moult usually initiate this some 3 weeks after the adults commence. In many adult females the moult is inhibited during lactation and again during the winter so that some individuals may be found moulting in all months of the year. The importance of considering annual pelage characters when using colour taxonomically in bats is emphasized, and possible relationships between moult and reproductive cycles are indicated. In addition the use of pelage characteristics, in conjunction with reproductive criteria as a means of recognizing age groups of M. s. blepotis, is discussed.


1978 ◽  
Vol 29 (3) ◽  
pp. 311 ◽  
Author(s):  
JP Glaister

Relationships between river discharge and production (catch) of the school prawn M. macleayi were examined as part of an ecological study of this species in the Clarence River region. Schooling behaviour of juvenile M. macleayi exhibited a lunar periodicity and mean daily abundance peaked 5 days after full moon. This was followed 7 days later by a peak in mean daily abundance of emigrating juvenile M. macleayi. Fluctuations in the magnitude of the oceanic component of the total annual catch were found to determine the difference between high and low production seasons. During the period examined there was a direct relationship between Clarence River discharge and the oceanic component of total production of M. macleayi, for various time periods. The absence of a persistent trend in total annual production and annual catch per unit effort of M. macleayi in the Clarence River region suggests that the stock has not been overfished. Common peaks in mean monthly oceanic production of M. macleayi off the Clarence, Evans and Richmond Rivers suggest a common enhancement of the seasonal emigration of M. macleayi from the three estuaries in November due to increased river discharges. Successive troughs and peaks in mean monthly oceanic production suggest a northwards migration of M. macleayi from the Clarence and Evans Rivers and subsequent recruitment to the Evans and Richmond ocean fisheries respectively. Results indicate the importance of river discharge to production of M. macleayi and suggest that modification of discharges by restriction of freshwater flow could adversely effect production.


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