Characteristics and consequences of movement patterns of King George whiting (Perciformes : Sillaginodes punctata) in South Australia

2002 ◽  
Vol 53 (7) ◽  
pp. 1055 ◽  
Author(s):  
A. J. Fowler ◽  
G. K. Jones ◽  
R. McGarvey
Keyword(s):  
Fishery Management ◽  
South Australia ◽  
Shallow Waters ◽  
Rocky Reef ◽  
Fish Movement ◽  
The South ◽  
Age Classes ◽  
Australian Population ◽  
Northern Areas ◽  
Considerable Period

The characteristics of movement of the South Australian population of King George whiting (Sillaginodes punctata) were determined through analysis of tag and recapture records collected from three tagging periods: (i) 1968–1969; (ii) 1978–1985; and (iii) 1986–1987. The characteristics were compared between the northern and southern parts of two large fishery regions, and determined for fish tagged at different sizes and ages. Fish tagged in the northern Gulf St Vincent and Spencer Gulf moved southwards up to several hundred kilometres, but those tagged in the southern areas showed no systematic directional displacement. Most fish tagged were subadults or young, immature adults at 2–4 years of age. Small, young fish did not move far until a considerable period after tagging, whereas some fish >300 mm total length (TL) at tagging moved substantial distances within only a few weeks. Fish movement resulted in a significant ontogenetic habitat shift, from relatively protected shallow waters that support extensive meadows of seagrass, to southern, exposed, deeper waters and rocky reef. As a result of this systematic, directional displacement the age structures of the fishery catches also varied systematically throughout the two regions. In the northern areas these were simple and dominated by the 3+ age class, whereas in the south they were complex and consisted of the 2+ to 17+ age classes. Because the latter were the spawning populations, fish movement is an obligate step in the life history that ultimately results in supplementation of numbers on the spawning grounds. The consequences for fishery management are discussed.

Recurrent gonorrhoea in South Australia, 1987 - 2003

Sexual Health ◽  
2006 ◽  
Vol 3 (3) ◽  
pp. 197
Author(s):  
Katina D'Onise ◽  
Russell Waddell
Keyword(s):  
South Australia ◽  
Recurrent Infections ◽  
The South ◽  
Australian Population ◽  
Core Group ◽  
The Core ◽  
Torres Strait ◽  
Sex With Men

In Australia, it is unclear if individuals are being recurrently infected with gonorrhoea, a proxy for identifying core groups. We reviewed all notified gonococcal (GC) infections in South Australia between 1987 and 2003. A case of repeated GC infection is one in which at least one further episode of GC infection occurred after 30 days and within 365 days of the first infection. There were 253 recurrent infections (7.26%) from 238 individuals. Men who have sex with men (MSM) and Aboriginal and Torres Strait Islanders (ATSI) were significantly more likely to be recurrently infected with gonorrhoea than the rest of the South Australian population. This method of identifying individuals who have recurrent gonococcal infections can be used to target more frequent screening for individuals in a population who are more likely to be a part of the core group.

Information security in the South Australian real estate industry

2014 ◽  
Vol 22 (1) ◽  
pp. 24-41 ◽  
Author(s):  
Deepa Mani ◽  
Kim-Kwang Raymond Choo ◽  
Sameera Mubarak
Keyword(s):  
Risk Management ◽  
Information Security ◽  
Real Estate ◽  
South Australia ◽  
Security Threats ◽  
The South ◽  
Content Type ◽  
The Real ◽  
The Real Estate ◽  
Real Estate Sector

Purpose – Opportunities for malicious cyber activities have expanded with the globalisation and advancements in information and communication technology. Such activities will increasingly affect the security of businesses with online presence and/or connected to the internet. Although the real estate sector is a potential attack vector for and target of malicious cyber activities, it is an understudied industry. This paper aims to contribute to a better understanding of the information security threats, awareness, and risk management standards currently employed by the real estate sector in South Australia. Design/methodology/approach – The current study comprises both quantitative and qualitative methodologies, which include 20 survey questionnaires and 20 face-to-face interviews conducted in South Australia. Findings – There is a lack of understanding about the true magnitude of malicious cyber activities and its impact on the real estate sector, as illustrated in the findings of 40 real estate organisations in South Australia. The findings and the escalating complexities of the online environment underscore the need for regular ongoing training programs for basic online security (including new cybercrime trends) and the promotion of a culture of information security (e.g. when using smart mobile devices to store and access sensitive data) among staff. Such initiatives will enable staff employed in the (South Australian) real estate sector to maintain the current knowledge of the latest cybercrime activities and the best cyber security protection measures available. Originality/value – This is the first academic study focusing on the real estate organisations in South Australia. The findings will contribute to the evidence on the information security threats faced by the sector as well as in develop sector-specific information security risk management guidelines.

Size Distributions and Growth of the Fan-shell Pinna bicolor Gmelin (Mollusca : Eulamellibranchia) in South Australia

1979 ◽  
Vol 30 (1) ◽  
pp. 25 ◽  
Author(s):  
AJ Butler ◽  
FJ Brewster
Keyword(s):  
South Australia ◽  
Adductor Muscle ◽  
Size Distributions ◽  
Limited Data ◽  
Length Frequency ◽  
Age Classes ◽  
Frequency Distributions ◽  
Growth And Survival ◽  
Random Samples ◽  
Variable Success

Fourteen random samples of Pinna bicolor were collected over a period of 31 months from 6 m depth in Gulf St Vincent off Edithburgh, South Australia. The length-frequency distributions suggest that: P. bicolor larvae settle in spring but with variable success; growth of newly settled young is rapid over summer; by age 1 year their modal shell length is about 20 cm; by age 2 it is about 26 cm; they may survive substantially longer than 3 years so that a length-class of mode c. 35 cm is always present and is composed of several age-classes not necessarily equally represented. These suggestions are corroborated by limited data on adductor muscle scars, the development of epibiota on the shells, and the growth and survival of tagged animals over 9 months.

scholarly journals Objective determination of the sea age of Atlantic salmon from the sizes and dates of capture of individual fish

2010 ◽  
Vol 68 (1) ◽  
pp. 130-143 ◽  
Author(s):  
Philip J. Bacon ◽  
William S. C. Gurney ◽  
Eddie McKenzie ◽  
Bryce Whyte ◽  
Ronald Campbell ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Fishery Management ◽  
East Coast ◽  
Probability Distributions ◽  
Age Classes ◽  
Individual Fish ◽  
Bivariate Probability ◽  
Management And Conservation ◽  
Objective Determination

Abstract Bacon, P. J., Gurney, W. S. C., McKenzie, E., Whyte, B., Campbell, R., Laughton, R., Smith, G., and MacLean, J. 2011. Objective determination of the sea age of Atlantic salmon from the sizes and dates of capture of individual fish. – ICES Journal of Marine Science, 68: 130–143. The sea ages of Atlantic salmon indicate crucial differences between oceanic feeding zones that have important implications for conservation and management. Historical fishery-catch records go back more than 100 years, but the reliability with which they discriminate between sea-age classes is uncertain. Research data from some 188 000 scale-aged Scottish salmon that included size (length, weight) and seasonal date of capture on return to the coast were investigated to devise a means of assigning sea age to individual fish objectively. Two simple bivariate probability distributions are described that discriminate between 1SW and 2SW fish with 97% reliability, and between 2SW and 3SW fish with 70% confidence. The same two probability distributions achieve this accuracy across five major east coast Scottish rivers and five decades. They also achieve the same exactitude for a smaller recent dataset from the Scottish west coast, from the River Tweed a century ago (1894/1895), and for salmon caught by rod near the estuary. More surprisingly, they also achieve the same success for rod-caught salmon taken at beats remote from the estuary and including capture dates when some fish could have been in the river for a few months. The implications of these findings for fishery management and conservation are discussed.

Age and growth of the shortfin mako (Isurus oxyrinchus) in the south-eastern Pacific off Chile

2009 ◽  
Vol 60 (5) ◽  
pp. 394 ◽  
Author(s):  
Francisco Cerna ◽  
Roberto Licandeo
Keyword(s):  
Growth Parameters ◽  
Eastern Pacific ◽  
Age And Growth ◽  
The South ◽  
Age Classes ◽  
Vertebral Centra ◽  
South Eastern ◽  
Isurus Oxyrinchus ◽  
Shortfin Mako ◽  
Longline Fisheries

The shortfin mako, Isurus oxyrinchus, is a large pelagic shark with a widespread global distribution. However, very little is known about most aspects of this species for the south-eastern Pacific. In the present paper, the age and growth parameters of the shortfin mako, caught by Chilean swordfish longline fisheries from 2004 to 2005, are reported. Ages were estimated by counting band-pairs from sections of vertebral centra from 547 individuals, ranging from 76 to 330 cm in total length (TL). Trends in the proportion of opaque edges for all ages combined and grouped into ages 0–6 and 7–26 years indicated that they are formed during summer and showed that annually, one band-pair is formed in the vertebrae of shortfin makos. Modal-progression analysis was used to verify the first three age classes (ages 0–2 years). For both sexes, the oldest estimated age was 25+ years. Von Bertalanffy growth parameters were estimated at L∞ = 325.29 cm TL, K = 0.076 year–1 and t0 = –3.18 years for females and L∞ = 296.60 cm TL, K = 0.087 year–1 and t0 = –3.58 years for males. The results indicated that this species is highly vulnerable to exploitation and, thus, urgent conservation measures are required.

Approaches to Delivering Child and Adolescent Mental Health Services: The South Australian Experience

1995 ◽  
Vol 29 (2) ◽  
pp. 230-237 ◽  
Author(s):  
Michael Gifford Sawyer ◽  
Robert John Kosky
Keyword(s):  
Mental Health ◽  
Mental Health Services ◽  
Health Services ◽  
Children And Adolescents ◽  
Mental Health Problems ◽  
South Australia ◽  
Adolescent Mental Health ◽  
Child And Adolescent ◽  
The South ◽  
Number Of Children

Approximately 10% of children and adolescents experience mental health problems, however only a small proportion receive specialised help. Identifying approaches which can provide a balanced and effective service for the large number of children and adolescents with problems is currently a major challenge for child and adolescent mental health services in Australia. In South Australia, following a review in 1983, child and adolescent services were reorganised into two separate but closely related services. This paper draws on experience in South Australia over the last decade to identify approaches which can be employed in six key areas that significantly influence the effectiveness of child and adolescent mental health services. The paper also describes the specific features which were included in the South Australian child and adolescent mental health service to address these issues.

Assessing population sustainability and response to fishing in terms of aggregation structure for greenlip abalone (Haliotis laevigata) fishery management

2004 ◽  
Vol 61 (2) ◽  
pp. 247-259 ◽  
Author(s):  
Natalie A Dowling ◽  
Stephen J Hall ◽  
Richard McGarvey
Keyword(s):  
Egg Production ◽  
Fishery Management ◽  
Management Strategies ◽  
South Australia ◽  
Fertilization Success ◽  
Adult Density ◽  
Demographic Feature ◽  
Data Set ◽  
Functional Relationships ◽  
Aggregation Size

The greenlip abalone (Haliotis laevigata) population in Waterloo Bay, South Australia, has undergone collapse and fishery closure twice since 1978. A rich data set, including survey measures of degree of spatial aggregation, has been gathered over that time and provides a unique opportunity to identify factors accounting for persistence or collapse, an issue that is of significance to abalone fisheries worldwide. Statistical analyses of fishery and survey data were undertaken to infer functional relationships between catch, effort, recruitment, adult density, and extent of aggregation. Catch rates were hyperstable, an observation consistent with the targeting of large aggregations. Statistical analysis of recruitment showed a significant year effect, implying an environmental signal, and suggested that aggregation size impacts fertilization success. Aggregation size grew under closure, suggesting an impact of fishing on this demographic feature. Aggregative behaviour appears to be critical for subpopulation sustainability. Fishery collapse may be triggered by depletion of larger abalone aggregations by heavy fishing, resulting in declines in fertilized egg production. When heavy fishing coincides with unfavourable environmental conditions, recruitment may be insufficient to sustain the subpopulation. If aggregation is similarly critical for other subpopulations, management strategies could be adapted according to the extent of aggregation in each subpopulation.

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