Teses / dissertações: "Western Australia. Department of Fisheries"

1

McAuley, Rory B. "Investigation of the fishery biology and population status of the sandbar shark (Carcharhinus plumbeus, Nardo 1827) in Western Australian waters". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2007. https://ro.ecu.edu.au/theses/280.

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The sandbar shark (Carchrarhinus plumbeus) is a commercially important shark species to fisheries around the world but is known to be highly susceptible to over·fishing. During the late 1990s, changes in the targeting practices of Western Australian demersal gillnet fishing vessels, and an expansion of targeted demersal longlining in the north of the State, caused a rapid escalation in C. plumbeus catches. This study therefore aimed to collect the biological and fishery data necessary to assess the impacts of increasing exploitation of the species and to develop biologically appropriate techniques for assessing the sustainability of these fishery developments.

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Obregón, Lafuente Clara. "The social-ecological dimensions of small-scale crab fisheries in Western Australia". Thesis, Obregón Lafuente, Clara (2021) The social-ecological dimensions of small-scale crab fisheries in Western Australia. PhD thesis, Murdoch University, 2021. https://researchrepository.murdoch.edu.au/id/eprint/62281/.

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The pivotal role of humans in social-ecological systems has been globally recognised, particularly for fisheries, yet human dimensions are often overlooked. The blue swimmer crab (Portunus armatus) is the most popular recreational fishery in south-western Australia and also supports a small-scale commercial fishery. This study analysed the human dimensions of this fishery using qualitative and quantitative data, including those extracted from interviews with commercial and recreational fishers, newspaper records and the literature. Social network analysis was used to define the fishery network structure and communication patterns between stakeholders. Government agencies and the commercial sector were identified as key groups for information sharing within the network. The results also revealed potential logistical and institutional barriers to effective communication between different groups. Additionally, historical records and fisher surveys were used to understand fishers’ perceptions of changes in crab stocks’ through time and revealed a perceived decrease in the average size of the crabs in the Peel-Harvey Estuary, which paralleled trends evident in the literature. Non-parametric analyses of interview data on the beliefs and attitudes of recreational and commercial fishers towards stock enhancement found that fishers understand the benefits and drawbacks of this approach but considered that the benefits were more likely to occur. Further investigation identified some differences (e.g., length of the seasonal closure) and commonalities (e.g., reducing fishing and increasing compliance) between recreational and commercial fishers’ concerns and the management approaches they supported. Finally, commercial fishers voiced a feeling of marginalisation influenced by new management measures implemented in 2019. They perceived the buyout of commercial licenses as limiting their access to the resource, while the lack of a shore-based recreational fishing license was seen to support the recreational sector. These new insights into commercial and recreational fishers’ views and understanding of the resource could be utilised to provide direction for future research and management of blue swimmer crab fisheries in south-western Australia. This is the first baseline study of the human dimensions of a fishery in Western Australia and provides an important contribution to understanding fisheries’ human dimensions in Australia and elsewhere.

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3

Riordan, Geraldine M. "Triage in Health Department of Western Australia accident and emergency departments". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 1995. https://ro.ecu.edu.au/theses/1182.

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A survey of triage systems used in Health Department of Western Australia accident and emergency departments was undertaken to examine differences in practices between departments with and without designated triage nurses (TNs). One questionnaire surveyed 93 nurses in seven departments with TNs, a similar second questionnaire surveyed 89 nurses in 16 departments without TNs, and a third questionnaire was used in a structured telephone interview of receptionists in hospitals without TNs. Data were analysed using frequencies, percentages, means, standard deviations and ranges with common themes identified for open ended questions. The study was guided by Donabedian's systems evaluation model. The structures and processes of triage within each department were examined in relation to the outcome standards recommended by the Australian Council on Healthcare Standards. The study results revealed that triage nurses were employed in all departments where patient attendances exceeded 300 per week and nursing staff coverage in the department was higher than five per day. Three departments had introduced triage on weekends only, and these departments had the lowest nurse-patient ratio of one nurse per day to 74 patients per week. The highest nurse-patient ratio was in departments with TNs (1-35). Conclusions drawn from the findings suggest that when receptionists are the first person to see patients, they triage patients using an unsatisfactory two category priority system. The average waiting time to see nursing staff is too long in departments without TNs, 7.6 minutes, as compared to 3. 7 minutes in department with TNs. Nursing staff perceived that triage systems could be improved by having only experienced staff as the triageur. The surveillance of patients entering the department is unsatisfactory as 81% of departments without TNs and 43% of departments with TNs are unable to provide nurse surveillance. The surveillance of the waiting room is similarly unsatisfactory in many departments. All triage areas are inadequate, as facilities for private conversation, hand washing and physical assessment are not always available. The majority of departments without TNs do not have a satisfactory triage priority category system in place. The average time taken by nursing staff to triage patients is an acceptable 3.2 minutes in departments with TNs, and 5.3 minutes in departments without TNs. The practice of redirecting patients away from the department could compromise patient safety as patients are redirected away from most departments by any level of staff employed in the department, without any written documentation kept or any written criteria for the redirection of these non-urgent patients. The practice of ordering investigations and treating minor problems without referring to a doctor could also compromise patient safety, as most departments do not have written policies and guidelines to cover this practice. Most departments offer an inadequate triage training program of preceptoring only. Recommendations are focused on the reviewing of existing triage practices to comply with the standards identified.

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4

Tapp, Nadia. "Do size differences of juvenile snapper (Pagrus auratus) in two regions of Shark Bay, Western Australia, reflect different environmental conditions". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2003. https://ro.ecu.edu.au/theses/1325.

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Aspects of the population biology of juvenile Pagrus auratus in the western gulf of Shark Bay, Western Australia, were investigated to explore the causes of an observed size difference between 0+ fish (first year of life) in the northern and southern regions of that gulf. Five trawl surveys were conducted in each region of the western gulf, from November 2000 to December 2001, to collect juvenile P. auratus. The 0+ fish from the northern region were found to be consistently greater in length by between 10 and 20mm LCF, than those in the southern region, thereby confirming those observed size differences. Three hypotheses were developed and investigated to explain the confirmed size difference between fish in the northern and southern regions of the western gulf. Size differences could be explained by (I) different growth rates; (2) age differences associated with different spawning times; and/or (3) fish migrating from south to north. The first and second hypotheses were tested by determining the daily ages of 125 fish collected by trawling in both regions between November 2000 and December 2001. Length-at-age data allowed the growth patterns of fish aged from 100 to 357 days to be tested using ANCOVA, while back-calculating from these ages allowed spawning times to be estimated. Examination of the third hypothesis was attempted by tagging 3485 0+ P. auratus in the southern region, followed by a trawling program to recapture tagged fish. Length-at-age data derived from validated age estimates indicated that while growth rates of O+ P. auratus, 100-357 days old, were similar between regions, the 0+ fish in the northern region were 15-l6mm greater in length than fish in the southern region, at a similar age. Back-calculated birth dates of O+ P. auratus showed that spawning had predominantly occurred between June and mid-August in both regions. While no tagged fish were recaptured during the study, independent studies examining the spatial movement of P. auratus in the western gulf suggest that 0+ P. auratus are unlikely to migrate between regions. Hence, the difference in length offish between regions almost certainly resulted from differences in growth rates within the first few months of life (age). A laboratory-based aquarium experiment was carried out at water temperatures of 18, 22 and 26oC and salinities of 36, 39 and 42% o to determine whether temperature and/or salinity influences growth of O+ P. auratus. ANOVA showed that growth, in terms of length, of 0+ P. auratus increased significantly at temperatures of 22 and 26oC compared to 18oC. Furthermore, in terms of weight, growth increased significantly with each 4oC increase in temperature. In comparison, growth was higher at salinities of 39%o than at 36 or 42%o but only in terms of length. Sea surface temperatures (SSTs) derived from remote-sensing satellite data demonstrated that P. auratus experienced SSTs 2-3oC cooler in the southern region compared to the northern region of the western gulf. In light of this, and the results of the aquarium experiment, depressed growth of wild 0+ P. auratus in the southern region was most likely due to the cooler water temperatures occurring during their first few months of life. The growth rate differences between the 0+ P. auratus of the northern and southern regions are discussed with regard to their lack of significance to the application of minimum size limits to adult P. auratus in Shark Bay. Further implications of the knowledge gained from this study to management practices applied to the snapper fishery in Shark Bay are highlighted and discussed. In particular, a recommendation was made to modify the dates of the closed snapper-fishing season around spawning to July-August of each year, rather than mid-August to September, as is currently the case. Knowledge gained from the present study is also highly applicable to any future P. auratus restocking programs in Shark Bay and may enhance the effectiveness of such projects by identifying: optimal temperature and salinity conditions for artificial rearing of snapper; favourable locations, times of year and optimal fish size for releases; and providing valuable advice regarding tagging methods.

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Yap, C. S. "Modelling and risk analysis of the western rock lobster (Panulirus cygnus) fishery of Western Australia". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 1995. https://ro.ecu.edu.au/theses/1462.

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The predictive power for short-term forecasting of selected biomass dynamic models was examined using the standardised catch and effort data from the 1944/45 to 1990/91 season of the western rock lobster. Risk analysis of the fishery based on the predicted fishing efforts with the Deriso-Schnute delay-difference model indicates a high probability of recruitment failure. Some hypothetical management strategies of reducing fishing effort were evaluated by taking into consideration the total catch and biological risk to the fishery.

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6

Fernandez, John. "Analysis of increases in fishing power in the western rock lobster (Panulirus cygnus) fishery". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 1999. https://ro.ecu.edu.au/theses/1227.

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The western rock lobster, Panulirus cygnus, fishery represents a significant commercial asset to Western Australia, and it is therefore important that appropriate strategies are developed to effectively manage it. Because the fishery has a very high level of exploitation, researchers and managers rely significantly on annual stock assessments which are based on catch and effort data. This study will identify and assess the effects that changes in fishing power factors (e.g. advances in fish-finding technology) have had on estimates of catch and effort. The fishing power increases can be used to adjust nominal fishing effort to produce a time series of standardised effort which can then be used to reassess stock abundance measures, particularly of the breeding stock. The study will utilise the theory and techniques of regression and generalised linear modelling. A comparison of the normal and gamma distributions as the specified probability distribution in the model will be made .

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7

Hancock, Andrew T. "The biology and fishery of Roe's abalone Haliotis roei Gray in south-western Australia, with emphasis on the Perth fishery". Connect to this title online, 2004. http://theses.library.uwa.edu.au/adt-WU2004.0068/.

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8

Reid, Bryan. "Implementing curriculum change within a state education department region : analysis and conceptualization". Murdoch University, 1986. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20060829.160229.

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The major aim of this study was to develop a conceptual model representing the implementation process of a curriculum change occurring in a State Education Department region. This development had its genesis in the now extensive body of literature related to the organizational phenomenon of planned change. Since its early development in the 1960ts, the study of planned change occurring i n organizations has grown in sophistication, encompassing a steadily evolving number of theoretical constructs. Such a construct, of recent origin, was that of perceiving implementation of the innovation as a discrete process within the total planned change process. Although stillinits infancy, this concept has attracted a steadily growing body of research, The present study co-ordi nated some of these findings to form the basis for a four-stage model representing the implementation process under a special set of circumstances. The application of the model was tested under field conditions. A longitudinal case study design was adopted because this was ideally suited to test the assumption of implementationas a process. The design was divided in to four sections : concepts related to the decision to change; concepts related to the effect the rationale for implementation had on teachers' behaviour; concepts related to the sequence of involvement of implementers; and finally, concepts related to the measurementof the degree of implementation for teachers and pupils. Field work was applied inarural educational region of the State of Western Australia. This region was established in 1979 as part of an Australia-wide trend. I t is well documented that at the commencement of the 19701s, Austral ian governmentcontrol led education systems were highly centralized. By the beginning of the 1980ts, all were facing major change, each incorporating some form of decentral ization. In Western Australia, a shift in power from central authorities to Regional Superintendents occurred. With the increase i n power, the Regions received more duties and became more complex organizations. To meet the demand of testing a complex theoretical model in the intricate field setting of a State Education Department region, a wide range of data-gathering techniques was used. Questionnaires were employed, some specifically designed to suit this study and some selected from other research. The breadth and depth of the data collected was extended by the use of interviews, both focused and unstructured. Information from a wide variety of perspectives was gathered by using direct observation. This was applied to the testing of the theoretical model and also used to validate data drawn from other sources. Content analysis techniques were also used to triangulate the findings from questionnaire and interview techniques. The findings of the analysis of the data,within a matrix of hypotheses and sub-hypotheses, provided powerful statistical evidence indicating that the innovation was judged as being implemented by the teachers and the pupils. Data collected were also analysed as part of the research plan incorporating four major hypotheses and twenty six sub-sections. Each sub-section has been investigated empirically. This strategy was used to test the applicability of the conceptual model as a technique to represent the process of implementation followed by an innovation in Oral English introduced into a rural region of a State Education Department. The model proved to be a very effective device, aiding in the comprehension of an implementation process that occurred under the particular conditions described in the thesis.

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9

Baharthah, Tara. "Comparison of three survey methods applied to the recreational rock lobster fishery of Western Australia". Connect to thesis, 2007. http://portal.ecu.edu.au/adt-public/adt-ECU2007.0039.html.

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10

Stella, Leonie. "Trawling deeper seas : the gendered production of seafood in Western Australia /". Access via Murdoch University Digital Theses Project, 1998. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040913.155811.

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11

au, andrew@recfishwest org, e Andrew Jay Rowland. "The biology of Samson Fish Seriola hippos with emphasis on the sportfishery in Western Australia". Murdoch University, 2009. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20091120.110541.

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This thesis had two overriding aims. The first was to describe the biology of Samson Fish Seriola hippos and therefore extend the knowledge and understanding of the genus Seriola. The second was to uses these data to develop strategies to better manage the fishery and, if appropriate, develop catch-and-release protocols for the S. hippos sportfishery. Trends exhibited by marginal increment analysis in the opaque zones of sectioned S. hippos otoliths, together with an otolith of a recaptured calcein injected fish, demonstrated that these opaque zones represent annual features. Thus, as with some other members of the genus, the number of opaque zones in sectioned otoliths of S. hippos are appropriate for determining age and growth parameters of this species. Seriola hippos displayed similar growth trajectories to other members of the genus. Early growth in S. hippos is rapid with this species reaching minimum legal length for retention (MML) of 600mm TL within the second year of life. After the first 5 years of life growth rates of each sex differ, with females growing faster and reaching a larger size at age than males. Thus, by 10, 15 and 20 years of age, the predicted fork lengths (and weights) for females were 1088 (17 kg), 1221 (24 kg) and 1311 mm (30 kg), respectively, compared with 1035 (15 kg), 1124 (19 kg) and 1167 mm (21 kg), respectively for males. Despite these differences, female and male S. hippos attained similar maximum age, i.e. 29 (1470 mm FL) and 28 years (1280 mm FL), respectively. The maximum age determined for S. hippos is greater than that recorded for any other Seriola spp. The largest female and male S. hippos recorded during this study were encountered during the tagging component and had fork lengths of 1600 mm and 1380 mm, respectively. Seriola hippos has a protracted spawning period, ca four months, which starts in late spring and continues through summer into early autumn during which time many individuals engage in large spawning aggregations on the lower west coast of Australia. The length at which 50 % of the females in the population reached maturity was 831 mm FL (888 mm TL) and approximately 4 years of age, whilst all females over 950 mm FL were mature. Whilst aggregated for spawning S. hippos ceases feeding, however, during the non-spawning period this species can best be described as an opportunistic carnivore which feeds on a variety of pelagic and demersal prey. This study has greatly increased our understanding of S. hippos movement on the west and south coasts of Australia and has documented, for the first time, the migratory behaviour of a carangid in these waters. Many S. hippos individuals undertake long distance migrations to join spawning aggregation sites near Rottnest Island. Individuals tagged at these aggregation sites where recaptured throughout this species distribution along the south coast of Australia, some after travelling distances of over 2400 km. Many S. hippos individuals displayed strong temporal and spatial spawning ground fidelity as numerous fish released at the spawning aggregations were recaptured at the exact same spawning site at similar times in subsequent years. Tagging data suggest that on the completion of spawning S. hippos individuals return to a resident location and remain in that general vicinity over the winter months. This study has developed a hypothesis describing larval dispersal associated with the S. hippos spawning behaviour exhibited near Rottnest Island. It is proposed that variations in the prevailing ocean currents, at this important spawning location throughout the protracted spawning period, leads to high intra and inter-annual variation in larval distribution and survival. The affect of this variation on the evolution of the spawning and migratory behaviour displayed by S. hippos is discussed. A recent increase in the popularity of S. hippos as a catch-and-release sportfish has led to concerns by some anglers about post release survival of this species, particularly due to the depth of capture. Short term mortality of S. hippos capture at the sportfishing sites was assessed by monitoring fish held within an enclosure near the site of capture for up to 31 hours post release. The total hooking mortality of S. hippos subjected to catch-and-release angling within the Rottnest Island sportfishery is approximately 8%. Most of this observed mortality is delayed and occurs sometime after release. Although best handling practises require ongoing development, the current level of mortality associated with this catch-and-release fishery is considered acceptable. Furthermore, this mortality is likely to have little effect on the S. hippos population due to the high abundance of this species and the fact that even the highest fishing effort yields a relatively low catch. Seriola hippos exhibits a typical teleost neuroendocrine stress response associated with catch-and-release. The physiological dysfunction associated with the stress of capture in this species does not appear to cause any post release mortality. Instead, most mortality was attributable to barotrauma, however, although mortality in S. hippos increases with capture depth, this species is much less susceptible to depth induced mortality than other commonly targeted species in which barotrauma has been observed. This study developed key handling protocols for fishers who catch-and-release S. hippos at the Rottnest Island aggregation sites. These protocols cover aspects of catch-and-release fishing such as hook type, water depth, time at surface, release method and shark predation. Almost all S. hippos observed during capture from deep water released large quantities of gas from the opercular region, particularly during the last 10 to 20 m before reaching the surface. This phenomenon has also been witnessed by divers and fishers to occur under natural conditions. Investigations into this release of gas revealed this physoclistous species to exhibit unique swim bladder characteristics. Seriola hippos possess a membranous tube that connects the posterior-dorsal surface of the swim bladder internally to a region under each operculum externally. This connection, termed the swim bladder vent, allows the escape of expanding swim bladder gases on rapid ascent. The presence of the swim bladder vent provides an explanation as to why the incidence of external barotrauma symptoms in S. hippos captured from the deepwater was low. The ability to expel excess swim bladder gases during rapid ascent whilst retaining full swim bladder function is likely to offer this semi-pelagic species considerable advantages when hunting prey, avoiding predators and engaging in spawning activities. Preliminary estimates of total mortality indicated that S. hippos is not currently subjected to a high level of fishing pressure. However, managers must remain mindful of the fact that the size at which females reach sexual maturity, i.e. 888 mm TL, is greater than the current minimum legal length, i.e. 600 mm, and thus fishers are currently allowed to harvest sexually immature fish. Furthermore, the effectiveness of future conservation measures must consider the large scale migration and spawning strategy undertaken by this species in order to ensure its protection. The collaborative research approach undertaken during this study demonstrated that a high level of community engagement produced a large amount of research interest, increased stakeholder satisfaction from project input, improved understanding of research outcomes, and increased research uptake, all of which has led to increased stewardship and conservation of the S. hippos fishery and fisheries resources in general. Indeed, projects of this nature would not be possible without this type of approach.

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au, gjackson@fish wa gov, e Gary Jackson. "Fisheries biology and management of pink snapper, Pagrus auratus, in the inner gulfs of Shark Bay, Western Australia". Murdoch University, 2008. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20081222.105104.

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This study explored an important aspect of the basis for the highly complex population structure of pink snapper (Pagrus auratus) within the inner gulfs of Shark Bay, investigated how growth and reproduction differ among these closely-adjacent but separate stocks, and obtained biomass estimates for each stock that are essential for the sustainable management of the regionally-important recreational pink snapper fishery. Using ichthyoplankton data in combination with hydrodynamic modelling, P. auratus eggs and larvae were shown to be retained within localized meso-scale eddies that were coincident with the main inner gulf spawning areas. Such hydrodynamic retention, in conjunction with tagging and otolith chemistry data that indicates very limited movement of juvenile and adult fish, explains how separate pink snapper populations can exist in the adjacent waters of the Eastern Gulf, Denham Sound and Freycinet Estuary. The study found significant variation in maximum age, growth, maturity and spawning time at fine spatial scales. Such variation, unusual for a large, potentially mobile fish inhabiting a marine environment with no obvious physical barriers, is linked to the inner gulfs marked environmental heterogeneity, the low levels of mixing and historic differences in fishing pressure among the three areas. The daily egg production method (DEPM) was used, for the first time with this species in Western Australia, to provide estimates of spawning biomass of the three separate inner gulf P. auratus stocks. While relatively imprecise, mostly due to imprecision in estimation of daily egg production, these estimates demonstrated that these stocks are very small (measured in tens of tonnes) compared with P. auratus stocks elsewhere in Australia and New Zealand. Biological data and DEPM estimates obtained from this study were incorporated in age-based stock assessment models that have been used to determine the status of inner gulf pink snapper stocks since 2002.

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Jackson, Gary. "Fisheries biology and management of pink snapper, Pagrus auratus, in the inner gulfs of Shark Bay, Western Australia /". Murdoch University Digital Theses Program, 2007. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20081222.105104.

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14

Jackson, Gary. "Fisheries biology and management of pink snapper, Pagrus auratus, in the inner gulfs of Shark Bay, Western Australia". Thesis, Jackson, Gary (2008) Fisheries biology and management of pink snapper, Pagrus auratus, in the inner gulfs of Shark Bay, Western Australia. PhD thesis, Murdoch University, 2008. https://researchrepository.murdoch.edu.au/id/eprint/664/.

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This study explored an important aspect of the basis for the highly complex population structure of pink snapper (Pagrus auratus) within the inner gulfs of Shark Bay, investigated how growth and reproduction differ among these closely-adjacent but separate stocks, and obtained biomass estimates for each stock that are essential for the sustainable management of the regionally-important recreational pink snapper fishery. Using ichthyoplankton data in combination with hydrodynamic modelling, P. auratus eggs and larvae were shown to be retained within localized meso-scale eddies that were coincident with the main inner gulf spawning areas. Such hydrodynamic retention, in conjunction with tagging and otolith chemistry data that indicates very limited movement of juvenile and adult fish, explains how separate pink snapper populations can exist in the adjacent waters of the Eastern Gulf, Denham Sound and Freycinet Estuary. The study found significant variation in maximum age, growth, maturity and spawning time at fine spatial scales. Such variation, unusual for a large, potentially mobile fish inhabiting a marine environment with no obvious physical barriers, is linked to the inner gulfs' marked environmental heterogeneity, the low levels of mixing and historic differences in fishing pressure among the three areas. The daily egg production method (DEPM) was used, for the first time with this species in Western Australia, to provide estimates of spawning biomass of the three separate inner gulf P. auratus stocks. While relatively imprecise, mostly due to imprecision in estimation of daily egg production, these estimates demonstrated that these stocks are very small (measured in tens of tonnes) compared with P. auratus stocks elsewhere in Australia and New Zealand. Biological data and DEPM estimates obtained from this study were incorporated in age-based stock assessment models that have been used to determine the status of inner gulf pink snapper stocks since 2002.

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15

Jackson, Gary. "Fisheries biology and management of pink snapper, Pagrus auratus, in the inner gulfs of Shark Bay, Western Australia". Jackson, Gary (2008) Fisheries biology and management of pink snapper, Pagrus auratus, in the inner gulfs of Shark Bay, Western Australia. PhD thesis, Murdoch University, 2008. http://researchrepository.murdoch.edu.au/664/.

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This study explored an important aspect of the basis for the highly complex population structure of pink snapper (Pagrus auratus) within the inner gulfs of Shark Bay, investigated how growth and reproduction differ among these closely-adjacent but separate stocks, and obtained biomass estimates for each stock that are essential for the sustainable management of the regionally-important recreational pink snapper fishery. Using ichthyoplankton data in combination with hydrodynamic modelling, P. auratus eggs and larvae were shown to be retained within localized meso-scale eddies that were coincident with the main inner gulf spawning areas. Such hydrodynamic retention, in conjunction with tagging and otolith chemistry data that indicates very limited movement of juvenile and adult fish, explains how separate pink snapper populations can exist in the adjacent waters of the Eastern Gulf, Denham Sound and Freycinet Estuary. The study found significant variation in maximum age, growth, maturity and spawning time at fine spatial scales. Such variation, unusual for a large, potentially mobile fish inhabiting a marine environment with no obvious physical barriers, is linked to the inner gulfs' marked environmental heterogeneity, the low levels of mixing and historic differences in fishing pressure among the three areas. The daily egg production method (DEPM) was used, for the first time with this species in Western Australia, to provide estimates of spawning biomass of the three separate inner gulf P. auratus stocks. While relatively imprecise, mostly due to imprecision in estimation of daily egg production, these estimates demonstrated that these stocks are very small (measured in tens of tonnes) compared with P. auratus stocks elsewhere in Australia and New Zealand. Biological data and DEPM estimates obtained from this study were incorporated in age-based stock assessment models that have been used to determine the status of inner gulf pink snapper stocks since 2002.

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16

Hancock, Andrew. "The biology and fishery of Roe's abalone Haliotis roei Gray in south-western Australia, with emphasis on the Perth fishery /". Connect to this title, 2004. http://theses.library.uwa.edu.au/adt-WU2004.0068.

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17

Kangas, M. I. "Postlarval and juvenile western king prawn Penaeus latisulcatus Kishinovye studies in Gulf St Vincent, South Australia, with reference to the commerical fishery /". Title page, contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09phk159.pdf.

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au, wwhite@murdoch edu, e William Toby White. "Aspects of the biology of elasmobranchs in a subtropical embayment in Western Australia and of chondrichthyan fisheries in Indonesia". Murdoch University, 2003. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040510.154948.

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The first aim of this thesis was to test the hypothesis that the spatial and food resources in the nearshore waters of a subtropical embayment in Western Australia (Shark Bay) will be partitioned within and amongst the main elasmobranch species that occur in that large water body. The size and age compositions, growth rates and reproductive biology of females and males of the nervous shark Carcharhinus cautus in Shark Bay were then determined to better understand the mode of life of this abundant species in this embayment. The second aim was to determine the species and size compositions of chondrichthyans landed by fisheries employing different methods in south-eastern Indonesia. The implications of these data for management were next determined and aspects of the reproductive biology of the most abundant of those species were explored, in a very preliminary manner. The nearshore, shallow waters of Shark Bay are used as a nursery area by several shark species and the different habitats in those waters are partitioned, to a certain degree, amongst those species. Ten species of shark (5 families), five species of ray (4 families) and twelve species of teleost (10 families) were caught in those waters. Carcharhinus cautus was the most abundant species, contributing 59.9% to the total number of elasmobranchs and 42.3% to all fish caught. This species and Negaprion acutidens were collected mainly or entirely from unvegetated sites, whereas Rhizoprionodon acutus, Carcharhinus brevipinna and Chiloscyllium punctatum were caught largely or exclusively at the seagrass site. The number of elasmobranch species and number of individuals of elasmobranchs were greatest in the seagrass site and least in the unvegetated site where no vegetation was present nearby, and they were significantly less in the latter site than in the one where dense mangroves were present nearby. These two biotic variables were also significantly greater in summer and autumn than in winter when temperatures were lowest. The species composition of elasmobranchs in each habitat type almost invariably differed significantly from that in each of the other habitat types and there was evidence that the species composition of elasmobranchs varied in a similar seasonal manner at the three unvegetated sites. Carcharhinus cautus, and probably also Hemigaleus microstoma and Chiloscyllium punctatum, were the only species that completed their life cycles in the nearshore, shallow waters of Herald Bight. However, the capture of the juveniles of a further four species with umbilical scars emphasises the importance of these waters as a nursery habitat for shark species. The dietary compositions of one ray species (Rhinobatus typus) and three shark species (Carcharhinus cautus, Negaprion acutidens, Rhizoprionodon acutus) undergo size-related changes and differ among these species, thereby reducing the potential for competition for food within and among these four species. Rhinobatus typus fed almost exclusively on penaeid prawns and portunid crabs, which is reflected in its narrow dietary breadth, whereas different species of teleosts constituted a major component of the diets of each size class of the three shark species. The relative contributions of the different species of teleost to the diets of the three shark species varied. The variations in dietary composition among the four species reflect differences in behaviour, modes of feeding and relative mouth sizes. Carcharhinus cautus copulates in late Octoberearly November, shortly followed by ovulation (and thus conception) and parturition occurs about 11 months later. The reproductive cycle of C. cautus is biennial. Female and male C. cautus reached ca 28 and 32% of their lengths at their maximum observed ages, respectively, at the time of parturition. Females and males of C. cautus attained maximum total lengths of 1330 and 1110 mm, respectively, and maximum ages after parturition of 16 and 12 years, respectively. Maturity was attained at about 1010 mm by females and 910 mm by males and at least 50% of females and males had become mature by the end of their sixth and fourth years of life, respectively. The three-parameter von Bertalanffy growth curves provided reasonably good fits to the lengths at age of females and males of C. cautus during just postnatal life and throughout the whole of pre- and postnatal life. However, the four-parameter Schnute growth curve significantly improved the fit to these data for both females and males from conception and for females from birth. The question of when, from a biological view point, it might be appropriate to switch from using a von Bertalanffy growth curve to the more complex Schnute growth curve are discussed. A total of 139 chondrichthyan species, comprising 77 species of shark representing 17 families, 61 species of ray representing 11 families and a single species of holocephalan, were recorded at the ten landing sites surveyed in south-eastern Indonesia. However, it should be recognised that up to 49 of the 139 chondrichthyan species recorded have apparently not yet been described and thus assigned a species name. The most speciose and commonly recorded families were the Dasyatidae and Carcharhinidae, which collectively contributed 84.8%, respectively, to the total number of individuals of all species. The use of MDS ordination demonstrated that the species compositions at the eight main landing sites reflected to a greater extent the fishing methods used rather than the geographical location of those sites. Data on the reproductive biology of males demonstrated that a number of elasmobranch species were fished prior to the time that they attained maturity. The three most abundant chondrichthyan species that were caught both as juveniles and adults were Dasyatis kuhlii, Dasyatis zugei and Himantura walga. Since the reproductive cycle of each of these species did not follow a seasonal pattern, the timing of conception and parturition and the duration of gestation of these species could not be determined. The fecundity of these three species was very low, i.e. maximum of two but usually only a single embryo. The size at maturity of the three species, using data on the prevalence of mature fish, ranged from minima of 163 mm for females and males of H. walga to maxima of 237 mm for females and 239 mm for males of D. kuhlii. The translucent zones on the vertebral centra of D. kuhlii were apparently deposited annually and were thus used to estimate the ages of the individuals of this species. The maximum estimated ages of female and male D. kuhlii were 15 and 10 years, respectively.

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19

White, William T. "Aspects of the biology of elasmobranchs in a subtropical embayment in Western Australia and of chondrichthyan fisheries in Indonesia /". Access via Murdoch University Digital Theses Project, 2003. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040510.154948.

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20

White, William Toby. "Aspects of the biology of elasmobranchs in a subtropical embayment in Western Australia and of chondrichthyan fisheries in Indonesia". Thesis, White, William Toby (2003) Aspects of the biology of elasmobranchs in a subtropical embayment in Western Australia and of chondrichthyan fisheries in Indonesia. PhD thesis, Murdoch University, 2003. https://researchrepository.murdoch.edu.au/id/eprint/402/.

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The first aim of this thesis was to test the hypothesis that the spatial and food resources in the nearshore waters of a subtropical embayment in Western Australia (Shark Bay) will be partitioned within and amongst the main elasmobranch species that occur in that large water body. The size and age compositions, growth rates and reproductive biology of females and males of the nervous shark Carcharhinus cautus in Shark Bay were then determined to better understand the mode of life of this abundant species in this embayment. The second aim was to determine the species and size compositions of chondrichthyans landed by fisheries employing different methods in south-eastern Indonesia. The implications of these data for management were next determined and aspects of the reproductive biology of the most abundant of those species were explored, in a very preliminary manner. The nearshore, shallow waters of Shark Bay are used as a nursery area by several shark species and the different habitats in those waters are partitioned, to a certain degree, amongst those species. Ten species of shark (5 families), five species of ray (4 families) and twelve species of teleost (10 families) were caught in those waters. Carcharhinus cautus was the most abundant species, contributing 59.9% to the total number of elasmobranchs and 42.3% to all fish caught. This species and Negaprion acutidens were collected mainly or entirely from unvegetated sites, whereas Rhizoprionodon acutus, Carcharhinus brevipinna and Chiloscyllium punctatum were caught largely or exclusively at the seagrass site. The number of elasmobranch species and number of individuals of elasmobranchs were greatest in the seagrass site and least in the unvegetated site where no vegetation was present nearby, and they were significantly less in the latter site than in the one where dense mangroves were present nearby. These two biotic variables were also significantly greater in summer and autumn than in winter when temperatures were lowest. The species composition of elasmobranchs in each habitat type almost invariably differed significantly from that in each of the other habitat types and there was evidence that the species composition of elasmobranchs varied in a similar seasonal manner at the three unvegetated sites. Carcharhinus cautus, and probably also Hemigaleus microstoma and Chiloscyllium punctatum, were the only species that completed their life cycles in the nearshore, shallow waters of Herald Bight. However, the capture of the juveniles of a further four species with umbilical scars emphasises the importance of these waters as a nursery habitat for shark species. The dietary compositions of one ray species (Rhinobatus typus) and three shark species (Carcharhinus cautus, Negaprion acutidens, Rhizoprionodon acutus) undergo size-related changes and differ among these species, thereby reducing the potential for competition for food within and among these four species. Rhinobatus typus fed almost exclusively on penaeid prawns and portunid crabs, which is reflected in its narrow dietary breadth, whereas different species of teleosts constituted a major component of the diets of each size class of the three shark species. The relative contributions of the different species of teleost to the diets of the three shark species varied. The variations in dietary composition among the four species reflect differences in behaviour, modes of feeding and relative mouth sizes. Carcharhinus cautus copulates in late October-early November, shortly followed by ovulation (and thus conception) and parturition occurs about 11 months later. The reproductive cycle of C. cautus is biennial. Female and male C. cautus reached ca 28 and 32% of their lengths at their maximum observed ages, respectively, at the time of parturition. Females and males of C. cautus attained maximum total lengths of 1330 and 1110 mm, respectively, and maximum ages after parturition of 16 and 12 years, respectively. Maturity was attained at about 1010 mm by females and 910 mm by males and at least 50% of females and males had become mature by the end of their sixth and fourth years of life, respectively. The three-parameter von Bertalanffy growth curves provided reasonably good fits to the lengths at age of females and males of C. cautus during just postnatal life and throughout the whole of pre- and postnatal life. However, the four-parameter Schnute growth curve significantly improved the fit to these data for both females and males from conception and for females from birth. The question of when, from a biological view point, it might be appropriate to switch from using a von Bertalanffy growth curve to the more complex Schnute growth curve are discussed. A total of 139 chondrichthyan species, comprising 77 species of shark representing 17 families, 61 species of ray representing 11 families and a single species of holocephalan, were recorded at the ten landing sites surveyed in south-eastern Indonesia. However, it should be recognised that up to 49 of the 139 chondrichthyan species recorded have apparently not yet been described and thus assigned a species name. The most speciose and commonly recorded families were the Dasyatidae and Carcharhinidae, which collectively contributed 84.8%, respectively, to the total number of individuals of all species. The use of MDS ordination demonstrated that the species compositions at the eight main landing sites reflected to a greater extent the fishing methods used rather than the geographical location of those sites. Data on the reproductive biology of males demonstrated that a number of elasmobranch species were fished prior to the time that they attained maturity. The three most abundant chondrichthyan species that were caught both as juveniles and adults were Dasyatis kuhlii, Dasyatis zugei and Himantura walga. Since the reproductive cycle of each of these species did not follow a seasonal pattern, the timing of conception and parturition and the duration of gestation of these species could not be determined. The fecundity of these three species was very low, i.e. maximum of two but usually only a single embryo. The size at maturity of the three species, using data on the prevalence of mature fish, ranged from minima of 163 mm for females and males of H. walga to maxima of 237 mm for females and 239 mm for males of D. kuhlii. The translucent zones on the vertebral centra of D. kuhlii were apparently deposited annually and were thus used to estimate the ages of the individuals of this species. The maximum estimated ages of female and male D. kuhlii were 15 and 10 years, respectively.

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21

White, William Toby. "Aspects of the biology of elasmobranchs in a subtropical embayment in Western Australia and of chondrichthyan fisheries in Indonesia". White, William Toby (2003) Aspects of the biology of elasmobranchs in a subtropical embayment in Western Australia and of chondrichthyan fisheries in Indonesia. PhD thesis, Murdoch University, 2003. http://researchrepository.murdoch.edu.au/402/.

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The first aim of this thesis was to test the hypothesis that the spatial and food resources in the nearshore waters of a subtropical embayment in Western Australia (Shark Bay) will be partitioned within and amongst the main elasmobranch species that occur in that large water body. The size and age compositions, growth rates and reproductive biology of females and males of the nervous shark Carcharhinus cautus in Shark Bay were then determined to better understand the mode of life of this abundant species in this embayment. The second aim was to determine the species and size compositions of chondrichthyans landed by fisheries employing different methods in south-eastern Indonesia. The implications of these data for management were next determined and aspects of the reproductive biology of the most abundant of those species were explored, in a very preliminary manner. The nearshore, shallow waters of Shark Bay are used as a nursery area by several shark species and the different habitats in those waters are partitioned, to a certain degree, amongst those species. Ten species of shark (5 families), five species of ray (4 families) and twelve species of teleost (10 families) were caught in those waters. Carcharhinus cautus was the most abundant species, contributing 59.9% to the total number of elasmobranchs and 42.3% to all fish caught. This species and Negaprion acutidens were collected mainly or entirely from unvegetated sites, whereas Rhizoprionodon acutus, Carcharhinus brevipinna and Chiloscyllium punctatum were caught largely or exclusively at the seagrass site. The number of elasmobranch species and number of individuals of elasmobranchs were greatest in the seagrass site and least in the unvegetated site where no vegetation was present nearby, and they were significantly less in the latter site than in the one where dense mangroves were present nearby. These two biotic variables were also significantly greater in summer and autumn than in winter when temperatures were lowest. The species composition of elasmobranchs in each habitat type almost invariably differed significantly from that in each of the other habitat types and there was evidence that the species composition of elasmobranchs varied in a similar seasonal manner at the three unvegetated sites. Carcharhinus cautus, and probably also Hemigaleus microstoma and Chiloscyllium punctatum, were the only species that completed their life cycles in the nearshore, shallow waters of Herald Bight. However, the capture of the juveniles of a further four species with umbilical scars emphasises the importance of these waters as a nursery habitat for shark species. The dietary compositions of one ray species (Rhinobatus typus) and three shark species (Carcharhinus cautus, Negaprion acutidens, Rhizoprionodon acutus) undergo size-related changes and differ among these species, thereby reducing the potential for competition for food within and among these four species. Rhinobatus typus fed almost exclusively on penaeid prawns and portunid crabs, which is reflected in its narrow dietary breadth, whereas different species of teleosts constituted a major component of the diets of each size class of the three shark species. The relative contributions of the different species of teleost to the diets of the three shark species varied. The variations in dietary composition among the four species reflect differences in behaviour, modes of feeding and relative mouth sizes. Carcharhinus cautus copulates in late October-early November, shortly followed by ovulation (and thus conception) and parturition occurs about 11 months later. The reproductive cycle of C. cautus is biennial. Female and male C. cautus reached ca 28 and 32% of their lengths at their maximum observed ages, respectively, at the time of parturition. Females and males of C. cautus attained maximum total lengths of 1330 and 1110 mm, respectively, and maximum ages after parturition of 16 and 12 years, respectively. Maturity was attained at about 1010 mm by females and 910 mm by males and at least 50% of females and males had become mature by the end of their sixth and fourth years of life, respectively. The three-parameter von Bertalanffy growth curves provided reasonably good fits to the lengths at age of females and males of C. cautus during just postnatal life and throughout the whole of pre- and postnatal life. However, the four-parameter Schnute growth curve significantly improved the fit to these data for both females and males from conception and for females from birth. The question of when, from a biological view point, it might be appropriate to switch from using a von Bertalanffy growth curve to the more complex Schnute growth curve are discussed. A total of 139 chondrichthyan species, comprising 77 species of shark representing 17 families, 61 species of ray representing 11 families and a single species of holocephalan, were recorded at the ten landing sites surveyed in south-eastern Indonesia. However, it should be recognised that up to 49 of the 139 chondrichthyan species recorded have apparently not yet been described and thus assigned a species name. The most speciose and commonly recorded families were the Dasyatidae and Carcharhinidae, which collectively contributed 84.8%, respectively, to the total number of individuals of all species. The use of MDS ordination demonstrated that the species compositions at the eight main landing sites reflected to a greater extent the fishing methods used rather than the geographical location of those sites. Data on the reproductive biology of males demonstrated that a number of elasmobranch species were fished prior to the time that they attained maturity. The three most abundant chondrichthyan species that were caught both as juveniles and adults were Dasyatis kuhlii, Dasyatis zugei and Himantura walga. Since the reproductive cycle of each of these species did not follow a seasonal pattern, the timing of conception and parturition and the duration of gestation of these species could not be determined. The fecundity of these three species was very low, i.e. maximum of two but usually only a single embryo. The size at maturity of the three species, using data on the prevalence of mature fish, ranged from minima of 163 mm for females and males of H. walga to maxima of 237 mm for females and 239 mm for males of D. kuhlii. The translucent zones on the vertebral centra of D. kuhlii were apparently deposited annually and were thus used to estimate the ages of the individuals of this species. The maximum estimated ages of female and male D. kuhlii were 15 and 10 years, respectively.

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22

Vanderklift, Matthew A. "Influence of adjacent seagrass on the fish assemblages off sandy beaches". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 1996. https://ro.ecu.edu.au/theses/946.

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As we attempt to maintain marine biodiversity mainly by focussing on habitats, we need to understand how marine biodiversity is affected by seagrass loss. Although managers and researchers widely acknowledge that habitat loss results in changes to marine biodiversity, quantitative knowledge of these changes is generally poor. In this study, fish assemblages (as one component of the biodiversity of sandy beaches) were examined in Cockburn Sound, Western Australia, to assess patterns that may be related to presence or absence of adjacent seagrass beds, If consistent patterns are evident, they may enable predictions regarding the effects of seagrass loss on the fish assemblages. Prior to examination of this main question, seagrass and bare sand habitats were sampled as part of a pilot study. Analyses of the data collected concentrated on examining the biases and variability associated with different sampling gear, and changes in the precision of estimates derived from different levels of replication. Further consideration was given to reducing the relative weighting of very numerous species in analyses by examining the effects of data transformation. Results suggest that researchers seeking to detect a 'signal' of environmental change amid the 'noise' that results from variability in catches and the numerical dominance of a few species should select methods of sampling, levels of replication and types of data transformation with an understanding of the associated influences. The main sampling program was conducted in May-June and October November 1995 (months identified as suitable pre- and post-recruitment periods), over six beaches in Cockburn Sound. Assemblage and population level analyses indicated that consistent trends related to the presence of adjacent seagrass were not evident, as differences among beaches was the dominant spatial trend. Several environmental variables appeared to influence these differences. The most significant were water depth, wind, amount of drift seagrass and wave exposure. Degree of exposure and amount of drift seagrass probably had the greatest structuring effects on the species assemblages. Both were determined by the position of habitat patches in relation to wind direction and proximity of other habitats, Although patterns associated with the presence or absence of adjacent seagrass Were not clear, these findings indicated that seagrass beds had considerable influence on the fish assemblages of some beaches, Populations of some species changed between May-June and October November due to recruitment of juveniles to the beaches. Although juveniles of some species use other habitats, there is a strong suggestion that the beaches of Cockburn Sound are regionally important in the ecology of species such as Aldrichetta forsteri, Ammotretis elongatus, Sillago uittata and Sill ago schomburgkii. Seagrass loss in Cockburn Sound is unlikely to have affected the more mobile fish species, but is likely to have caused a decline in the populations of less mobile, site-associated species of both seagrass and sand habitats. Additional loss of seagrass within Cockburn Sound is likely to further reduce the populations of many species. If these components of biodiversity are to be maintained, then management of marine biodiversity in the region needs to be conducted with a recognition of the differences in assemblage composition among habitat patches. Conservation of just a few habitat patches will not adequately represent the full range of species and age classes present.

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23

Farag, Saarah A. "A comparison of advanced time series models for environmental dependent stock recruitment of the western rock lobster". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 1998. https://ro.ecu.edu.au/theses/997.

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Time series models have been applied in many areas including economics, stuck recruitment and the environment. Most environmental time series involve highly correlated dependent variables, which makes it difficult to apply conventional regression analysis, Traditionally, regression analysis has been applied to the environmental dependent stock and recruitment relationships for crustacean species in Western Australian fisheries. Alternative models, such as transfer function models and state space models have the potential to provide unproved forecasts for these types of data sets. This dissertation will explore the application of regression models, transfer function models, and state space models to modelling the puerulus stage of the western rock lobster (Panulirus Cynus) in the fisheries of Western Australia. The transfer function models are consulted to examining the influences of the environment on crustacean species and can be used where correlated variables are involved. These models aim at producing short-term forecasts that may help in the management of the fisheries. In comparison with regression models, TFM models gave better forecast values with state space models given the forecast values in the first two years. Overall, it was shown that environmental effects, westerly winds and the Leeuwin Current, have a significant effect on the puerulus settlement for Dongara and Alkimos. It was also shown that westerly winds and spawning stock have a significant effect on the puerulus settlement at the Abrolhos Islands.

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24

Huddleston, Veronica. "Restructuring and adjustment in resource-dependent coastal communities : a case study of the Western rock lobster fleet hosting communities". University of Western Australia. Faculty of Natural and Agricultural Sciences, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0001.

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In an attempt to address the seeming imbalance within studies of rural communities in Australia linked to primary industries, this study examines the broader aspects of policy changes and bio-economic imperatives in the Western Rock Lobster Fishery and the effects of the restructuring of the fishery on communities that host the rock lobster fleet. It is an innovative study in that it is one of the first comprehensive studies of industry restructuring in the fisheries sector; a study of the linkages and implications of restructuring on the social, economic and cultural facets of coastal communities in Western Australia. Globalisation in the fishery sector, aided by technological advances, has resulted in a greater exploitation of high-value fisheries for export. Intensified globalisation has also brought about environmental and social standards that ensure the survival of by-catch species and promote responsible codes of fishing practice. In Australia, the active support of the government for globalisation, led to the adoption of export-oriented policies emphasising competitiveness and efficiency. Consideration of market principles thus govern fisheries regulators when deciding on the management arrangements to adopt for a particular fishery. In considering a number of policy instruments and management measures, government regulators also consider the conservation of marine resources alongside the production of significant economic and social benefits. The Western Rock Lobster Fishery is the most valuable single species fishery in Western Australia with a sizeable financial and employment contribution to coastal communities along the Western Australian coast. Any management scheme adopted for this fishery, as such, not only has to take into account biological and environmental imperatives but also economic and social objectives. The analysis of the fishery undertaken in this thesis underlines the need for a holistic view of fishery management that takes into consideration not only biological sustainability, but also promotes an understanding of fishers' behaviours and fishing patterns and the consequent effects on specific communities. The demographic and social changes that affect rural communities further complicate the economic restructuring at the fishery level, with fishers' responses differing based on their circumstances and preferences. This thesis presents a snapshot of a fishery deliberating changes in management arrangements and its effects on coastal communities whose socio-demographic and economic development historically has depended, and to a great extent is still dependent, upon rock lobster fishing. It provides empirical evidence that lends support to the view that the pro-market policies promoting competition and entrepreneurialism have resulted in a spatially uneven development in regional Australia. Specific localities can deal with the changes brought about by globalisation and policy change. However, the manner in which these communities deal and cope with these changes depends on a number of factors, among others, the level of diversification of the local economy, demographic and social structures, and other factors such as the level of resilience and the social capital base within the community.

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25

Delacy, Caine Robert. "Latitudinal patterns in reef fish assemblage structure : the influence of long-term and short-term processes". University of Western Australia. School of Plant Biology, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0097.

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Latitudinal patterns in reef fish assemblages reflect the influence of long-term environmental conditions, evolutionary processes and the recent, short-term influence of fishing. Long-term processes generate the typically common latitudinal patterns in reef fish assemblages, such as decreases in diversity and herbivory towards higher latitudes. These patterns reflect the global gradient in water temperature and the isolation of temperate regions from the tropics. Fishing also influences reef fish assemblages in that it decreases the abundance of large-bodied carnivore species on reefs, often leading to over-exploitation, depletion and in some cases the extirpation of populations. Indirectly, the removal of these large-bodied carnivores can influence the abundance of their prey, leading to an increase in non-target species. This study examines the latitudinal patterns in reef fish assemblages across a unique biogeographic region, the temperate Western Australian coast, and incorporates an investigation of the influence of fishing on the structure of these assemblages. Seven regions across seven degrees of latitude and seven degrees of longitude covering approximately 1500 km of coastline were sampled. Fish assemblages were characterised at each region using diver operated stereo-video transects. At each region, four locations, and within each location, four reefs were surveyed totalling 1344 transects. A significant gradient in water temperature exists with latitude and longitude. Along the Western Australian coast, and in contrast to other regions species diversity of reef fish increased towards higher latitudes and there was no evidence for a decrease in the biomass and abundance of herbivorous reef fish. The presence of the poleward flowing warm water Leeuwin current combined with the absence of major extinction events means the temperate Western Australian coast contrasts with global latitudinal trends in reef fish assemblage structure. The unique biogeographic history of temperate Western Australia has also generated a high degree of endemism among reef fish. Nearly 30 % of the species found along the west coast in this study are endemic to Western Australia, with the narrow range of these species playing an important role in the large scale patterns and spatial vi heterogeneity in reef fish assemblage structure. Furthermore, many of these endemic species are large-bodied carnivores and targeted by fishers. The impact of fishing on the abundance of large-bodied carnivores throughout the Western Australian temperate region is clear both spatially and temporally. The distribution of fishing effort is greatest along the west coast and decreases towards the south following the gradient in SST. Along the west coast, high levels of fishing effort have reduced the biomass and abundance of target carnivores to well below the standing biomass of the south coast where a low level of fishing effort occurs. This reduction in biomass is related to the historical declines in catch per unit effort (CPUE) of many key target species. These target species include endemic species such as Choerodon rubescens, Glaucosoma herbraicum, Epinephilides armatus Nemadactylus valenciennesi and Achoerodus gouldii.

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26

Hancock, Andrew (Boze) T. "The biology and fishery of Roe's abalone Haliotis roei Gray in south-western Australia, with emphasis on the Perth fishery". University of Western Australia. School of Animal Biology, 2004. http://theses.library.uwa.edu.au/adt-WU2004.0068.

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The Roe’s abalone (Haliotis roei) fishery near Perth, Western Australia, is uniquely accessible, and highly vulnerable to overexploitation. The sustainability of this intensively utilized fishery requires robust assessment. To facilitate an assessment, this research aimed to provide rigorous and detailed biological information with appropriate interpretation. Four critical aspects of the species’ biology and population dynamics were investigated: (1) the stock structure; (2) the recreational catch; (3) an appropriate growth curve and description of size at age; and (4) abundance measures against which to assess the impact of fishing mortality. Allozyme electrophoresis was used to investigate stock structure across the species’ distribution. Standardized variance in allelic frequencies between 10 sites in south-western Australia indicated high levels of gene flow across the 3000 km sampled (mean FST = 0.009). An isolation-by-distance was evident when pairwise measures of GST were related to geographic distance (r=0.45, P<0.001). The area of complete genetic mixing was estimated from samples within the Perth fishery to be less than the distance between the two nearest sites, or 13 km. Consequently, the Perth fishery comprises numerous discrete stocks, each requiring independent assessment. A possible mechanism for this population structure is the retention of larvae in the wind driven currents oscillating in the near-shore lagoons, with rare pulses of long distance dispersal via the southerly Leeuwin current, running further offshore. The presumed impact of intensive recreational fishing, combined with substantial commercial quotas for the Perth fishery, had led to tight restrictions on fishing effort, without any quantitative measure of the recreational catch. A stratified creel survey was adapted to estimate the effort, catch rate and mean weight of abalone harvested by the recreational sector. Catches were estimated for reef complexes, or stocks, of less than 10 nautical miles (18.5 km) of coast. Between 1997 and 2000 the recreational catch varied from 30 to 45 tonnes whole weight, approximately equivalent to the commercial quota of 36 tonnes. On average 88% of the recreational catch came from two stocks, while 98% of the commercial catch came from these two, and one additional, stocks. The incidental mortality from recreational fishing, measured as the number of abalone left dead on the reef as a proportion of the estimated catch, was approximately 7% and 20% at two sites surveyed. Spatial and temporal patterns of growth were examined on the west coast of Western Australia. Growth increments were measured for abalone larger than about 30 mm from tagging studies at five sites in the Perth fishery, a site at the northern extent of the species’ distribution and a site in the southwest. Mean annual growth increments of the 0+ year class were obtained by fitting components to length frequencies from five sites in the Perth fishery, and combined with growth increments from each Perth tag site for model fitting. A von Bertalanffy growth curve provided a slightly better fit to the tag data, but a Gompertz growth curve was a much better fit when the mean increment from the 0+ to 1+ cohort was included, with the inflection occurring at about 40 mm, the size at sexual maturity. There was no difference in annual growth between the two years studied. There was significant variation in growth between the reef platform and adjacent sub-tidal reef, but this variation was site specific and faster growth rates were not consistently associated with either habitat. There was no latitudinal trend in growth rate. Growth at the Perth sites was the fastest and similar at all five sites with growth increments greater in summer than in winter. Size and abundance of abalone were measured using fixed transects and quadrats. Abalone densities were highest on the outer edge of the platform, intermediate in the middle of the reef platform, and lowest on both the inner platform and the sub-tidal reef. The pattern of mean lengths of abalone was the inverse of the density. Mean length and abundance were driven by the presence of post-settlement juveniles on the outer and middle reef habitats. There was a high spatial variation in abundance, with densities varying between transects at the same site, but the trend between years for each transect at a site was not significantly different. Abalone abundances, by size class, were examined from sites sampled between 1996 and 2002. A low density of post-settlement juveniles at all sites in 1997 was reflected in low densities of the 1+ and 2+ year classes in subsequent years. Abalone abundances at an unfished site were steady over the seven years. Two sites were located within each of the main stocks utilised by the recreational fishery. Abundance was stable or increasing in one stock, corresponding to a stable total catch. In the second stock the total catch increased over time and abundances declined. Perth is the focus of the Roe’s abalone fishery, with recreational and commercial fishers take about equal shares of the annual catch. Stocks are highly subdivided, with most of this catch coming from only 3 stocks occupying about 20 nautical miles of coast. Growth rates were found to be lower than previous estimates, and more similar to other commercial species of abalone. All life history stages are highly habitat specific, particularly the recruits, and the distribution and abundance through time indicate that the main stocks are near, or slightly over, the limit of sustainable fishing.

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27

Baharthah, Tara. "Comparison of three survey methods applied to the recreational rock lobster fishery of Western Australia". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2007. https://ro.ecu.edu.au/theses/2.

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A mail survey of recreational rock lobster licence holders has been conducted annually since 1986. The results from this survey have been used in the management of the recreational rock lobster fishery in Western Australia. Mail surveys are susceptible to non-response and recall bias. The key to determining useful estimates of fishing catch and effort is to minimise both biases. Telephone recall surveys, with high response rates, effectively eliminate nonresponse bias. However, they still suffer from recall bias when the recall period is greater than two months. Telephone diary surveys are free of non-response bias and recall bias and provide the most accurate estimates of effort and catch. In the 2001/02 season three independent surveys were conducted to estimate the recreational catch and fishing effort of the 37,000 fishers licensed to fish for rock lobsters.

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28

Srisurichan, Sukanlaya. "Time series modelling of the environmental factors affecting the daily catch rate of western rock lobster". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2001. https://ro.ecu.edu.au/theses/1511.

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The western rock lobster fishery is one of the most significant and valuable single species fisheries in Australia and in the world. It generates a gross commercial value of $200-300 million dollars per year for the economy of Western Australia. The impact of environmental factors on the daily catch rate of the western rock lobster is of particular interest to the W.A. Marine Research Laboratories, at the Ministry of Fisheries, Western Australia. Considerable time and effort has been invested into building and developing suitable models to measure such impact on this fishery. While past research has focussed on monthly or seasonal data, this study investigated appropriate time series analyses to model the effect of major environmental factors such as lunar cycle, swell, and sea water temperature on the daily catch rate data of the western rock lobster at different depths. The variation in western rock lobster daily catch rate data for two periods ("whites" and "reds") and four categories (undersize, legal size, spawner, and setose ), was examined for three management zones, A, B, and C. Regression and transfer function models for relationships between catch rates and environmental data were considered and compared. Results show that the lunar cycle especially the presence of the full moon and the swell has a significant impact on the daily catch rates of the Western rock lobster. The results of this research assist in the development of improved models to support the management of this very valuable resource.

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29

Bloot, Regina D. "Reasons for the underrepresentation of females at Head of Department level in physical education in government secondary schools in Western Australia: Perceptions of female physical education teachers". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 1992. https://ro.ecu.edu.au/theses/1130.

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This study focuses on reasons why so few females hold Head of Department positions in physical education in government secondary schools in Western Australia. Despite the almost equitable proportion of females and males teaching the subject, and the absence of Ministry of Education policy constraints on female promotion since 1972, females remain grossly underrepresented in leadership roles. In 1991, women held only five (7%) of the 70 substantive Head of Department appointments. Individual indepth interviews were used as the means of data collection to document female teachers' own accounts of their lives, career aspirations, and what they perceived to be the barriers and encouragements for promotion in physical education. A sample of female physical education teachers was selected and subdivided into three groups based on their years of teaching experience and occupancy of Head of Department positions. The intention of such a categorization was to obtain a broad spectrum of perceptions, and to facilitate comparison between the groups to indicate the varying effects that changing Ministry of Education policies and societal expectations have had on the promotional prospects and aspirations of female physical educators. The factors that emerged as constraints to the promotion of females were based primarily on stereotypic attitudes and expectations regarding gender-roles, and comprised both external systemic and internalized psychological barriers. It is proposed that many of the perceived deterrents are in fact created in the minds of female teachers to mask their lack of self-confidence and/or ambition. For this reason, social settings from studentship, through teacher education, to the teaching environment can play a crucial role in shaping and nurturing the career decisions and aspirations of female teachers. Finally, recommendations based on the findings are made to three key groups, namely, the Ministry of Education; teacher education institutions; and female physical education teachers. The suggested measures to address the problem focused on the need to do more than just change policy. Education regarding promotion; the identification and sponsorship of potential female candidates; the provision of networking and support groups; mentoring by female leaders; and a non-discriminatory selection process are among the essential strategies needed to stimulate and nurture the promotional aspirations of female physical education teachers.

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30

Venter, Nico. "An examination of the implementation of selected batho pele principles: A case study of the Western Cape Department of Agriculture, Forestry and Fisheries (DAFF) and its selected clients". University of the Western Cape, 2018. http://hdl.handle.net/11394/6334.

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Magister Administrationis - Madmin
The Batho Pele principles can be seen as a tool to help transform the South African public sector by making it more responsive to the needs of its citizens. The White Paper on the Transformation of the Public Service strives to enhance service delivery to all South Africans (Taylor,2007).The role of the Batho Pele principles is to improve service delivery within the public sector and to assist with the transformation of a public sector that is more effective and people centred. However, if these principles are ignored, it will lead to a public sector that only caters to the needs of the middle class and higher-income groups, thus leaving the lowerincome citizens with a substandard of service delivery. Batho Pele means to put the people first; however, that can only take place if these principles are implemented correctly and continuously and their successes and challenges monitored and addressed (RSA, 1997b). If the people are not valued, it will lead to a scenario where citizens lose trust in government. This in turn, could lead to a decrease in active public participation. By not engaging and consulting with the people, government will not adhere to the very first of the Batho Pele principles. Service delivery to all citizens and a responsive public sector are yet to be achieved (Taylor, 2007. Matas argues that the South African public sector lacks effectiveness and efficiency and as a result of this, unequal service delivery is experienced by millions of South Africans (Matas, 1994. The main research objective of this study is to examine the implementation process of the Batho Pele principles through the case of the Western Cape Department of Agriculture, Forestry and Fisheries (DAFF) and how it influences its interactions with relevant clients/citizens. The reason why this department was selected was due to the fact that this department within the Western Cape was solely responsible for assisting wine farm owners across the country with the necessary submissions of wine samples and scientific laboratory reports. This process facilitates the testing, approval and marketing of the wines produced.

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31

Phillips, Catharine. "Prisoner, prison and situational characteristics and their relationship with the prevalence, incidence and type of prison offending recorded by a sample of prisoners within Western Australian prisons". Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2019. https://ro.ecu.edu.au/theses/2163.

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The importance that researchers and prison administrators have placed on ensuring that the good governance, security and safety of prisons are maintained has generated a number of studies of prison offending. Previous studies have identified several prisoner, prison and situational characteristics as relevant in regard to their relationship with the prevalence, incidence and type of prison offences committed. However, no studies have been conducted in Australia, and therefore no studies have included Aboriginal prisoners in their prisoner samples. In addition, the differences in regard to legislation pertaining to prison offending between jurisdictions is also of importance when considering the generalisability of the body of research available on the subject. The present study involved the examination of the relationship between several prisoner and prison characteristics and the prevalence and incidence of prison offending, and several prisoner, prison and situational characteristics and the types of prison offences committed by male, female, Aboriginal and non-Aboriginal prisoner samples. The prevalence, incidence and type of prison offences were examined within and across all adult prison facilities in Western Australia, and included all adult prisoners who had spent the full 12-month study period in prison within Western Australia. Logistic regression and multiple regression analyses revealed that several prisoner and prison characteristics were significantly related to with the prevalence and incidence of prison offending, while logistic regression analyses revealed that several prisoner, prison and situational characteristics were significantly related to the type of prison offences committed by male, female, Aboriginal and non-Aboriginal prisoners included in the prisoner sample. The present study provides a useful addition to the existing body of research due to it being the first of its kind to include Aboriginal prisoners in an Australian context. The present study also provides generalisable findings to other Australian prisoner populations, and may prove to be of practical importance to other Australian jurisdictions, particularly those where the overrepresentation of Aboriginal people is of an extent similar to that of Western Australia. Practical interventions informed by the findings of the present study may help to reduce the prevalence and incidence of prison offending, and the severity of such offending, which may subsequently improve the security of prisons, the safety of staff, prisoners and visitors, and reduce the financial implications for prison systems, governments and taxpayers in respect of compensation for injured prison staff, prisoners or visitors, costs associated with the rectification of damage caused by prisoners, and costs associated with the administrative processes relating to the progression of formal prison charges.

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Alomari, Ali H. "Stressors and coping strategies for emergency department nurses in New South Wales of Australia". Thesis, 2019. http://hdl.handle.net/1959.7/uws:56126.

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Purpose: The aim of this study was to identify factors that contribute to stress for emergency departments (ED) nurses. In addition, this study identified some preferred strategies for ED nurses to minimise stress. Method: The research methodology is a cross-sectional survey. This survey was sent to a sample of ED nurses working in New South Wales (NSW), Australia. Two standardised scales were used in the survey, the Expanded Nursing Stress Scale (ENSS) and Maslach Burnout Inventory (MBI). The sampling method for this research is a non-probability purposive sampling approach. Results: The results of the study indicated that ED nurses in NSW experience stress in their work settings mostly because of problems in dealing with patients and their families, high workload, and uncertainty concerning treatment. In addition, the results outlined some of the preferred strategies that ED nurses in NSW use to minimise stress such as seeking workplace support, spending some quality time with friends and families, and implement self-regulation techniques like exercise, humour and meditation. Furthermore, the results showed that ED nurses in NSW experience high levels of burnout at their work settings. Conclusion: The results of this study provide useful implications for nurses, managers and educators in NSW, Australia. These implications can be used as one part of a suite of initiatives to minimise stress and a better working environment for ED nurses in NSW. Moreover, the study results can provide nursing students and newly graduate nurses who might start working in ED with useful insight and tips in dealing with stress at their work settings.

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33

Collins, Maree. "New World, Old Frontiers. An ecological perspective on the problem of attraction and retention of statutory child protection workers in the West Australian Department for Child Protection’s Murchison District: 2009–2012". Phd thesis, 2015. http://hdl.handle.net/1885/106001.

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The attraction and retention of statutory child protection workers in regional, rural and remote Australia has been identified at the national and state/territory level as a priority challenge for the child protection sector. This research emerged from the recognition of and response to this problem by the Government of Western Australia’s Department for Child Protection (the Department), Murchison District, and the Department’s search for evidence-based responses under the umbrella of the Australian Research Council Linkage Project ‘Pathways to Better Practice’ (LP0082806). The size and distribution of the Australian population, and the extreme nature of the physical environment, means that geographic and demographic characteristics of place are central to the challenges of service delivery in regional and remote Australia. Maintaining the supply of a skilled and professional workforce to these places is largely dependent on ‘migration’ employment models, particularly for professional workforces such as that of the Department. The significant over-representation of Aboriginal and Torres Strait Islander children in the child protection system is identified as presenting particular challenges. In Western Australia, the employment of Aboriginal people is integral to strategies across the sector to improve services and outcomes for Aboriginal children and families. The geographic distribution and demographic characteristics of the Aboriginal population in remote Western Australia suggest additional challenges for the delivery of child protection services in locations such as the Murchison District. This is due to a combination of factors, including the level of disadvantage and the complex needs of this client population, the limited resources in place, and the cultural dimension to practice. In seeking to develop an evidence-based response to the problem of attraction and retention of child protection workers in the Murchison an ecological model has served as both the conceptual and methodological framework for the research. This approach to the study of the problem has meant attending to the multiple settings in which the research is embedded, and the interplay between variables acting on attraction and retention. These variables range from the individual work and lifestyle choices to the organisational responses and local characteristics of place to the effects of the global labour market, and are consistent with reflexive theories in sociology. In exploring the dimensions of place, work and individual life choices to attraction and retention, the research has embraced a combination of methods: analysis of secondary statistical data to examine the characteristics of the Murchison and Department’s workforce; interviews; and surveys of the individual subjects of the Department’s interventions, the Murchison District workforce. The research reveals the complex web of both actual and potential factors that shape attraction and retention. These include changing preferences and life trajectories both in the work and non-work environment that demonstrate the limits of unilateral, organisational responses. The research reveals a number of paradoxical effects in relation to the Department’s strategies to attract and retain. These include the constraining effect of the introduction of changed qualifications requirements for child protection roles on supply, and the disconnect between the Department’s idealised representations and the realities of the places to which the Department seeks to attract and retain. The changing nature of place, work and the ‘life’ in late-modernity which reveal the heterogeneity of preferences presents both opportunities and challenges for future interventions.

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Ward, Charlie R. "Gurindji people and Aboriginal self-determination policy, 1973-1986". Thesis, 2017. http://hdl.handle.net/1959.7/uws:47353.

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In 1973, a newly-elected Australian Labor Party government led by Gough Whitlam described its new Aboriginal Affairs policy as one of Aboriginal self-determination. The policy proclaimed its intention to assist Aboriginal groups to achieve their own goals, and used the Northern Territory (over which the Commonwealth then had full control) as a proving ground for its implementation. Subsequently renamed self-management by the Fraser Government (1975–83), the policy was adapted in small but significant ways by every federal and Northern Territory Government in the period of this study (1973–86). The thinking of those who had formulated self-determination policy had been influenced by the situation and ambitions of the Gurindji people. The group had come to public attention following their Wave Hill Walk-off protest action of 1966, led by Vincent Lingiari. In the years afterwards, Lingiari and other Gurindji leaders articulated a number of goals, the achievement of which they saw as fundamental to their society’s wellbeing and viability. Those goals were: official recognition of their traditional rights to land; their operation of a cattle enterprise on that land; their establishment of an independent community there also; and the operation in that community of a ‘two-way’ school. This thesis recognises an apparent confluence of shared intentions among Gurindji leaders and government agencies in the self-determination era, and describes a zone of parallel Gurindji and government activity: ‘Gurindji self-determination’. Finding that three of Gurindji self-determination’s four goals were not or only fleetingly achieved, the task of this thesis is to identify the causes of this broad failure and singular success. To do this, the thesis draws on detailed empirical data, the policy history of the preceding decades, anthropological and ethnographic studies, and political theory. This thesis finds that Gurindji self-determination’s failure was caused by inchoate and emergent differences between the aims and methods of government agencies and the Gurindji. Equally, young Gurindji people’s social reform agendas were an important and unanticipated contributor to the failure of Gurindji self-determination. Increased cash incomes and broader policy shifts associated with ‘equal rights’ enabled younger Gurindji to conduct this reformation.

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