Shore-based recreational angling in the Rottnest Island Reserve, Western Australia: Spatial and temporal distribution of catch and fishing effort

2006 ◽  
Vol 12 (3) ◽  
pp. 238 ◽  
Author(s):  
C. B. Smallwood ◽  
L. E. Beckley ◽  
N. R. Sumner
Keyword(s):  
Western Australia ◽  
Temporal Distribution ◽  
Fishing Effort ◽  
Recreational Fishing ◽  
Temporal Data ◽  
Target Species ◽  
Southwestern Australia ◽  
Recreational Angling ◽  
Western Australian ◽  
Support Decision Making

The Rottnest Island Reserve, located off southwestern Australia, is one of the most popular recreational fishing locations in Western Australia. In the reserve, standard Western Australian recreational fishing regulations apply and there are two small "no-take" conservation sanctuary areas. A roving creel survey of shore-based recreational angling in the reserve was conducted from January to December 2003. In total, 1 053 anglers were recorded which included individuals, families, school groups and angling club members. The total annual shore-based angling effort for Rottnest island was calculated to be 23 899 angler outings and the total catch estimated at 53 994 retained fish. Fishing effort was concentrated in the settlement area on the eastern side of the island and the highest levels of catch and effort were recorded in April, May and July. During the survey, 33 fish species were identified in the catch and the small, pelagic species Australian Herring dominated with 7.27 tonnes caught during the study. Shore-based anglers also caught and released a large number of non-target species. The survey has provided spatial and temporal data that can be used as a benchmark and to support decision making by the Rottnest Island Authority with respect to biodiversity conservation and the Department of Fisheries with regard to management of shore-based recreational angling in the Rottnest Island Reserve.

Preliminary assessments of stocks of the Western Australian crayfish, Panulirus cygnus George

1966 ◽  
Vol 17 (1) ◽  
pp. 93 ◽  
Author(s):  
BK Bowen ◽  
RG Chittleborough
Keyword(s):  
Western Australia ◽  
Fishing Effort ◽  
Total Catch ◽  
Catch Per Unit Effort ◽  
Stock Size ◽  
Unit Effort ◽  
Exploitation Rate ◽  
Panulirus Cygnus ◽  
Western Australian ◽  
Closed Period

Total catch of Panulirus cygnus in Western Australia rose from 0.6 million lb in 1944-45 to 21.4 million Ib in 1962-63. Fishing effort increased rapidly with the result that the catch per unit effort declined progressively. Effort has been limited by regulation since 1963. From records of catch and effort from specified areas at intervals of one month throughout each season, estimates were made of mortality coefficients (Z1, F, and M1) and catchability coefficient (q). Stock size, recruitment, and exploitation rates were then estimated. As the seasonal catch per unit effort followed the same trend throughout all fishing areas, the detailed results from the selected areas have been applied to the whole fishery. The fishable stock, originally of approximately 140 million lb, had declined to some 35 million lb by 1963. Exploitation rate rose as effort was increased, and then levelled off (generally at above 60%), further increase in fishing effort resulting in a fall in the catchability coefficient rather than a change in the exploitation rate. Because of the high exploitation rate in recent years, the fishable stock available on the grounds at the opening of a season is largely dependent on recruitment (by growth) of juveniles during the preceding closed period. This recruitment has been diminishing from year to year, apparently because of mortality of undersize (pre-recruit) crayfish handled in fishing pots. Provision of escape gaps in all fishing pots is recommended. A sustainable level of catch might be 16,000,000±2,000,0001b per year if recruitment can be stabilized. Some further restriction of fishing effort might be necessary.

Factors that contribute to urban–rural gradients in risk of schizophrenia: Comparing Danish and Western Australian registers

2021 ◽  
pp. 000486742110096
Author(s):  
Oleguer Plana-Ripoll ◽  
Patsy Di Prinzio ◽  
John J McGrath ◽  
Preben B Mortensen ◽  
Vera A Morgan
Keyword(s):  
Confidence Interval ◽  
Western Australia ◽  
Urban Areas ◽  
Proportional Hazards ◽  
Cox Proportional Hazards ◽  
Hazard Ratio ◽  
Indigenous Status ◽  
Increased Risk ◽  
The Relationship ◽  
Western Australian

Introduction: An association between schizophrenia and urbanicity has long been observed, with studies in many countries, including several from Denmark, reporting that individuals born/raised in densely populated urban settings have an increased risk of developing schizophrenia compared to those born/raised in rural settings. However, these findings have not been replicated in all studies. In particular, a Western Australian study showed a gradient in the opposite direction which disappeared after adjustment for covariates. Given the different findings for Denmark and Western Australia, our aim was to investigate the relationship between schizophrenia and urbanicity in these two regions to determine which factors may be influencing the relationship. Methods: We used population-based cohorts of children born alive between 1980 and 2001 in Western Australia ( N = 428,784) and Denmark ( N = 1,357,874). Children were categorised according to the level of urbanicity of their mother’s residence at time of birth and followed-up through to 30 June 2015. Linkage to State-based registers provided information on schizophrenia diagnosis and a range of covariates. Rates of being diagnosed with schizophrenia for each category of urbanicity were estimated using Cox proportional hazards models adjusted for covariates. Results: During follow-up, 1618 (0.4%) children in Western Australia and 11,875 (0.9%) children in Denmark were diagnosed with schizophrenia. In Western Australia, those born in the most remote areas did not experience lower rates of schizophrenia than those born in the most urban areas (hazard ratio = 1.02 [95% confidence interval: 0.81, 1.29]), unlike their Danish counterparts (hazard ratio = 0.62 [95% confidence interval: 0.58, 0.66]). However, when the Western Australian cohort was restricted to children of non-Aboriginal Indigenous status, results were consistent with Danish findings (hazard ratio = 0.46 [95% confidence interval: 0.29, 0.72]). Discussion: Our study highlights the potential for disadvantaged subgroups to mask the contribution of urban-related risk factors to risk of schizophrenia and the importance of stratified analysis in such cases.

Potential impacts of poison baiting for introduced house mice on native animals on islands in Jurien Bay, Western Australia

2016 ◽  
Vol 43 (1) ◽  
pp. 61 ◽  
Author(s):  
Clifford Bennison ◽  
J. Anthony Friend ◽  
Timothy Button ◽  
Harriet Mills ◽  
Cathy Lambert ◽  
...  
Keyword(s):  
Western Australia ◽  
Rhodamine B ◽  
Native Species ◽  
House Mice ◽  
Mus Domesticus ◽  
Target Species ◽  
Island Populations ◽  
Delivery Technique ◽  
Poison Baiting ◽  
Competition For Resources

Context House mice (Mus domesticus) are present on Boullanger and Whitlock islands, Western Australia, and could potentially threaten populations of the dibbler (Parantechinus apicalis) and grey-bellied dunnart (Sminthopsis griseoventer) through competition for resources. A workshop in 2007 recommended a study to assess the feasibility of eradicating house mice from the islands by using poison baits and of the risk posed to non-target native species. Aim We aimed to assess the risk to non-target native species if poison baiting was used to eradicate house mice on Boullanger and Whitlock islands. Methods Non-toxic baits containing the bait marker rhodamine B were distributed on Boullanger Island and on the mouse free Escape Island to determine the potential for primary poisoning. Acceptance of baits by mammals was measured through sampling and analysis of whiskers, and by reptiles through observations of dye in faeces. To determine the potential for secondary exposure to poison, the response of dibblers to mouse carcasses was observed using motion-activated cameras. Bait acceptance was compared using two methods of delivery, namely, scattering in the open and delivery in polyvinyl chloride (PVC) tubes. A cafeteria experiment of bait consumption by dibblers was also undertaken using captive animals held at the Perth Zoo. Ten dibblers were offered non-toxic baits containing rhodamine B in addition to their normal meals; consumption of bait and the presence of dye in whiskers were measured. Key results Bait acceptance on the islands was high for house mice (92% of individuals) and dibblers (48%) and it was independent of bait-delivery technique. There was no evidence of bait acceptance by grey-bellied dunnarts. Dibblers may consume mice carcasses if available; however, no direct consumption of mice carcasses was observed with movement sensor cameras but one dibbler was observed removing a mouse carcass and taking it away. During the cafeteria experiment, 9 of 10 captive dibblers consumed baits. Conclusions This investigation demonstrated that dibblers consume baits readily and island populations would experience high mortality if exposed to poison baits. Poison baiting could effectively eradicate mice from Boullanger and Whitlock islands but not without mortality for dibblers. Implications Toxic baits could be used to eradicate mice from Boullanger and Whitlock islands, provided that non-target species such as dibblers were temporarily removed from the islands before the application of baits.

Life cycle of the western school prawn, Metapenaeus dalli Racek, in a Western Australian estuary

1986 ◽  
Vol 37 (1) ◽  
pp. 95 ◽  
Author(s):  
IC Potter ◽  
JW Penn ◽  
KS Brooker
Keyword(s):  
Life Cycle ◽  
Western Australia ◽  
Sexual Maturity ◽  
Second Year Of Life ◽  
Second Year ◽  
Australian Estuary ◽  
Western Australian

The absence of marine records for M. dalli below latitude 31�S., together with data on gonadal stages and spermatophore deposition on females of this species in the Swan estuary, provide very strong indications that the western school prawn typically breeds in estuarine environments in south-western Australia. The 0 + recruits, which first appeared in samples in February, remained in the estuary during the following months and by November had reached a size suitable for exploitation. At this time they were approaching sexual maturity and were starting to move from the shallows to the deeper waters of the estuary where they remained for their second year of life. In contrast to Australian Penaeus species, M. dalli mates during the intermoult period when the shell is hard rather than immediately after moulting.

scholarly journals Spatial and temporal distribution of fishing resources exploited by the Manaus fishing fleet, Amazonas, Brazil

2007 ◽  
Vol 67 (4) ◽  
pp. 651-656 ◽  
Author(s):  
VS. Batista ◽  
M. Petrere Jr
Keyword(s):  
Amazon Basin ◽  
Temporal Distribution ◽  
Fishing Effort ◽  
Fishing Ground ◽  
Rural And Urban ◽  
Environmental Variations ◽  
Fishing Resources ◽  
The Right ◽  
Urban People ◽  
Operational Aspects

Fishing resources are important generators of income and food for the rural and urban people in the Amazon. The present paper investigates fishing and environmental variables determining fishing production landed in Manaus and evaluates the relative abundance of commercial fishes in the different sub-systems of the Central Amazon basin. Information collected was used to test the new catch index derived from multiple regressions with the following significant variables: number of fisherman days fishing; distance of the fishing ground from Manaus; amount of ice carried during the trip; and river level. There were no significant differences between mean catch values of the Purus, Madeira and Juruá sub-systems. These results suggest that the tributaries of the right margin were very similar and were the most productive in commercial terms. The actual production varies according to the recent magnitude of fishing effort, environmental variations and operational aspects of fishing, particularly ice consumption.

Aspects of reproduction, and morphology of the penis, of Pseudantechinus woolleyae (Marsupialia : Dasyuridae)

2017 ◽  
Vol 65 (6) ◽  
pp. 357 ◽  
Author(s):  
P. A. Woolley
Keyword(s):  
Western Australia ◽  
Arid Regions ◽  
Wide Distribution ◽  
Erectile Tissue ◽  
Australian Museum ◽  
Seasonal Breeder ◽  
Males And Females ◽  
One Year ◽  
Western Australian

Woolley’s Pseudantechinus, P. woolleyae, has remained virtually unstudied in the 30 years since its recognition in 1988 as a species distinct from P. macdonnellensis. It has a wide distribution in arid regions of Western Australia. What little is known of its biology comes largely from studies carried out over the years 1988–91 on one wild-caught female and her offspring, and a few specimens held in the collection of the Western Australian Museum. P. woolleyae is a seasonal breeder and young are born from late July to early October. They mature when ~7 months old. Both males and females are potentially capable of breeding in more than one year. Males have accessory erectile tissue that does not form an appendage on the penis.

The Distribution of Phytophthora cinnamomi Rands at Two Sites in Southern Western Australia and at Durras in South-Eastern New South Wales.

1982 ◽  
Vol 30 (2) ◽  
pp. 139 ◽  
Author(s):  
WM Blowes ◽  
WA Heather ◽  
N Malajczuk ◽  
SR Shea
Keyword(s):  
Western Australia ◽  
Phytophthora Cinnamomi ◽  
New South ◽  
New South Wales ◽  
Native Forest ◽  
Prevention Strategies ◽  
South Eastern ◽  
Isolation Techniques ◽  
South Wales ◽  
Western Australian

Native forest at Durras in south-eastern New South Wales and Jarrahdale in south-western Western Australia was examined for the presence of Phytophthora cinnamomi by two sampling and isolation techniques. With the lupin seeding baiting technique, randomly selected samples of soil and fine roots collected from the New South Wales site yielded P. cinnamomi when baited, while similar baiting of comparable samples from Western Australia failed. Direct plating of samples of upper roots and root collars of recently dead Banksia grandis from Western Australian sites yielded P. cinnamomi, while this organism was not isolated from comparable samples of chlorotic Macrozamia communis collected at the New South Wales site. The results suggest that the form of occurrence of P. cinnamomi and its association with disease in Australia vary in different situations. Viewing each situation independently might ensure the adoption of control/prevention strategies appropriate to all.

scholarly journals Attributes for effective nurse management within the health services of Western Australia, Singapore and Tanzania

2013 ◽  
Vol 37 (2) ◽  
pp. 268 ◽  
Author(s):  
Duncan Boldy ◽  
Phillip Della ◽  
Rene Michael ◽  
Mark Jones ◽  
Shelley Gower
Keyword(s):  
Health Services ◽  
Transactional Leadership ◽  
Western Australia ◽  
Nurse Managers ◽  
Healthcare Management ◽  
Personality Characteristics ◽  
Management Effectiveness ◽  
Cultural Backgrounds ◽  
Beliefs And Values ◽  
Western Australian

Objective. To identify the perceptions of nurse managers in Western Australia, Singapore and Tanzania regarding desirable attributes for effective management of their health services, and to identify and discuss the implications for health-management education provided by Australian universities. Methods. Nurse managers completed a questionnaire covering four key dimensions: personality characteristics, knowledge and learning, skills, and beliefs and values. Each of 75 items were rated as to their effect on management effectiveness, according to a 5-point Likert scale. Results. Skills were considered the most important for management effectiveness by each group. Tanzanian respondents rated knowledge and learning almost as highly, and significantly higher than Western Australian respondents. They also rated personality characteristics and beliefs and values significantly higher than Western Australian respondents. No significant differences were found between Singapore and Western Australia. Conclusions. Participants desired a different relative mix of attributes in their nurse managers, with Western Australian respondents most likely to indicate that transformational leadership contributed most to managerial effectiveness. Tanzanian nurse managers were most likely to advocate transactional leadership, whereas Singaporean nurse managers’ views were located somewhere between. Given that these perceptions are valid, the content and curricula of management-development courses need to be cognisant of the cultural backgrounds of participants. What is known about the topic? Views differ as to the extent to which the criteria for management effectiveness are broadly universal or contingent on culture. This applies to the area of nurse management as it does to healthcare management in general. What does this paper add? It is demonstrated that each of the three quite different countries or states considered identified a distinctive combination of attributes as desirable, with the nurse managers of Western Australia most likely to favour a transformational style of leadership, those from Tanzania a transactional leadership style and those from Singapore somewhere in between. What are the implications for practitioners? Given the country- or state-specific desire for a different relative mix of attributes in their nurse managers, management educators in Australia need to ensure that the content and curricula of their courses are cognisant of the cultural backgrounds of their students. There are also important lessons to be taken on board regarding recruitment of nurses into management positions in terms of each of the four dimensions considered, particularly in terms of desirable personality characteristics and beliefs and values.

scholarly journals The risk to fishery performance associated with spatially resolved management of Antarctic krill (Euphausia superba) harvesting

2009 ◽  
Vol 66 (10) ◽  
pp. 2148-2154 ◽  
Author(s):  
Simeon L. Hill ◽  
Philip N. Trathan ◽  
David J. Agnew
Keyword(s):  
Antarctic Krill ◽  
Euphausia Superba ◽  
Ecosystem Approach ◽  
Fishing Effort ◽  
Target Species ◽  
Ecosystem Models ◽  
Spatially Resolved ◽  
Management Actions ◽  
Antarctic Krill Euphausia Superba

Abstract Hill, S. L., Trathan, P. N., and Agnew, D. J. 2009. The risk to fishery performance associated with spatially resolved management of Antarctic krill (Euphausia superba) harvesting. – ICES Journal of Marine Science, 66: 2148–2154. The ecosystem approach to fisheries attempts to define objectives for target species, the wider ecosystem, and critically, the fishery itself. Proposals for implementing the approach often include spatial restrictions on harvesting, so it is important to understand how these will affect fishery performance. One metric of potential performance is the probability of encountering exploitable densities of a target species at the scale of fishing operations. The probability of encountering exploitable densities of Antarctic krill, Euphausia superba, at the scale of 1 nautical mile during an acoustic survey was predicted by bathymetry and the mean krill density at the larger scale at which the fishery is managed. This suggests that the risk to fishery performance will increase if management actions relocate the fishery into deeper water. The results also suggest that ecosystem models resolved to the spatial scale of management units could usefully predict effects at the scale of fishing operations. However, correct parameterization of these models will require better characterization of threshold densities for efficient exploitation. Finally, the distribution of catch and fishing effort over an entire fishing season reflected the distribution of krill density observed during the survey.

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