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One of the main challenges for spiny lobster aquaculture is the successful development of formulated feeds that are attractive, readily consumed by lobsters and promote optimal growth and survival. In a 54-day growth trial, we investigated the performance of four moist formulated feeds containing A) non-homogenised flesh ingredients; B) fish meal only; C) 10% krill meal; or D) homogenised flesh ingredients; and a reference diet of shucked blue mussel (Mytilus galloprovincialis) flesh, on growth, nutritional condition and feeding behaviour of juvenile tropical spiny lobster (Panulirus ornatus) reared either communally or individually. Growth and survival achieved by lobsters fed mussel were significantly higher than all other treatments. However, lobsters fed the formulated feed containing 10% krill meal (treatment C) and reared communally had a significantly higher growth, survival and feeding performance when compared to the formulated feeds with inclusion of non-homogenised and homogenised flesh ingredients (treatments A and D). The highest levels of feed interaction and pellet consumption among the formulated feeds were also recorded for treatment C. We demonstrated that the inclusion of krill meal in formulated feeds provides a benefit when compared to the inclusion of the flesh ingredients. Flesh ingredient format (homogenised or non-homogenised) had no effect on growth performance of lobsters, suggesting that the process of homogenisation of flesh ingredients does not provide any benefit in promoting feed consumption. Furthermore, time-series photography analysis trials showed that all the formulated feeds only promoted a feeding response within the first 2–3 h post-feeding, whereas mussel retained its attractiveness throughout the feeding period. These results suggest that the prolonged attractiveness remains an impediment for formulated feed performance in lobster culture. The present study also showed that growth performance and feeding response were higher in lobsters reared communally than individually. As observed in other spiny lobster species, it is likely that social interactions in communal housing may have provided cues that stimulated feeding responses and promoted higher growth rates.

The literature on late-stage larval and puerulus settlement of tropical spiny lobsters suggests that a broad range of visually-assessed variables may play a role in the selection of settlement substrates. These variables include light level, luminosity, degree of exposure, and the availability of edges, crevices and clefts. A fishery has developed in Indonesia, that captures pueruli for grow-out purposes, along the entire southern coastline from Java to Sumbawa. The present study builds on knowledge gained on the behaviour and substrate preferences of settling pueruli by examining aspects of collector design and substrate surface characteristics in regard to catch rates. A series of tank-based experiments were used to examine preferences for various attributes of collector materials, and preferred material characteristics were then tested in a field experiment to verify the laboratory results. In the tank experiment the most preferred substrate was cement bag paper, followed by insect mesh, weed netting, PVC rubber and cement bag plastic. Crevice angles of 10° and 20° were significantly preferred over 30°. The substrate level and other substrates had less influence on settlement. However, both the lunar phase and type of materials tested in the field had a significant effect on settlement. Significantly greater numbers of pueruli were caught at the time of the new moon than at other moon phases. Cement bag paper was the most preferred material in the field, followed by cement bag plastic, insect mesh, weed fabric, and PVC rubber.

Indonesia has a unique opportunity to establish the world's largest lobster aquaculture industry, based on a significant natural resource of settling puerulus. These seed lobsters can be captured and on-grown to generate high value, consumption size lobsters. However, existing fisheries regulation prohibits fishing of these seed lobsters in Indonesia. Nevertheless, seed fishing occurs widely, and the seed are smuggled into Vietnam, where the Vietnamese gain most of the commercial benefit. By removing access to pueruli and grow-out opportunities, these regulations have diminished the capacity of Indonesian lobster farmers to develop a sustainable grow-out industry. Although the new policies were introduced as a management intervention to protect adult lobster stocks, they have had the unintended consequence of preventing development of lobster aquaculture while having no known benefit on abundance of adult lobsters. This study collected data on the puerulus available in Indonesia, species composition, seasonality, and capture methods. A census of seed capture determined that 5,243,887 pueruli were fished from two bays in the southeast of Lombok in 2014, representing 64,787 pueruli per km2. Surveys beyond Lombok determined there was high abundance of seed in areas with similar environmental characteristics, where local communities had also engaged in seed fishing. The locations identified as having substantial puerulus abundance comprised the southern coast of Java, Bali, Lombok and Sumbawa covering a distance of 1500 km. Puerulus abundance is highest in enclosed bays with distinct currents, relatively high turbidity attributable to terrestrial inflows, and muddy/sandy substrates. Satellite imaging identified all such suitable locations for puerulus settlement, enabling an estimate of total puerulus catch of 103,480,283 per year. The composition of puerulus fished consisted of two species, Panulirus homarus and P. ornatus. P. homarus was most abundant representing between 63 and 87%, while P. ornatus represented 37 to 13%. Seasonality of catch was unclear, with low catch between December and March and higher catches from April to November. The magnitude of the estimated puerulus resource of Indonesia is >20 times greater than that of Vietnam. If used for aquaculture, the seed available can support an industry generating >12,500 t of market size lobster, and provide social and economic benefit to many thousands of households. To achieve this, fisheries policies could be revised and a regulatory framework established to manage the puerulus fishery and support lobster farming. Tropical marine rock lobster aquaculture is a major opportunity for high-value aquaculture production for the Indonesian economy.

Spiny lobster farming is a feasible strategy to address increasing export demand currently not met by the capture fishery. However, farming currently relies on natural lobster seed availability, which in turn is limited by the fishers' lack of skill in catching and handling pueruli as well as applying suitable grow-out practises. In Indonesia, particularly on Lombok, a viable puerulus fishery has been established supporting a local grow-out industry. Anecdotal evidence suggests water depth may be an important factor for the effectiveness of collecting equipment. This paper reports on an experiment that examined the effect of depth and trap type on the effectiveness of puerulus collectors at the end of the wet season, when pueruli abundance is greatest. Four trap types were deployed at 5 depths: i) 1 m below surface; ii) 2 m below surface; iii) middle of the water column; iv) 1 m above the sea floor; and v) touching the sea floor, with 6 replicates of each. The data were analysed to identify the effect of depth and trap type using a two-way ANOVA. Significant differences for depth and trap type were found for the primary species caught, Panulirus homarus and Panulirus ornatus . The greatest catch of P. homarus was on the sea floor using a cement paper trap. For P. ornatus catch rate was less strongly correlated with a specific depth or trap type, although catch was highest at or near the sea floor in cement paper traps.

Dietary supplementation with mannan oligosaccharide (MOS) has been demonstrated to provide significant benefits to growth and health of many species of fish and crustaceans. An investigation was made to assess the effect of MOS supplementation on the diet of the tropical lobster Panulirus homarus. The aim of the study was to test the effect of various dietary inclusion levels of MOS on growth, survival rate, intestinal morphology and bacterial abundance, haemocyte make-up, and tissue composition of P. homarus lobsters. A manufactured, semi-moist diet was used as a basal diet and supplemented with 0.2%, 0.4%, 0.6% and 0.8% MOS inclusion, and fed to lobsters with an initial mean weight of 0.16 g for 56 days. A typical fishery bycatch mixture was used as a reference control diet. Growth rate of lobsters was significantly higher for those fed diets supplemented with 0.4 and 0.6% MOS than those fed an un-supplemented diet or bycatch. Survival rates of lobsters ranged from 68 to 78%. The survival rate was significantly higher in lobsters fed diets with 0.2% and 0.4% MOS supplementation and bycatch, compared with those fed the basal or 0.6% MOS diet. There was no significant difference in differential haemocyte count of lobsters fed with various MOS levels or bycatch. The mid-gut surface area of lobsters fed diets supplemented with 0.2%, 0.4% and 0.6% MOS was significantly higher than that of lobsters fed on control, 0.8% MOS or bycatch. The total Vibrio count in the mid-gut of lobsters fed any MOS diet was significantly lower than that of lobsters fed either the control or the bycatch diet. There was no significant difference in protein, lipid or ash content in lobsters fed the different diets. There were significant correlations between concentrations of MOS in diets and lobster growth rates. Optimal MOS concentration was estimated to be 0.69% at day 14 (R2 = 76.79%), 0.55% at day 28 (R2 = 88.18%), 0.48% at day 42 (R2 = 97.72%) and 0.47% at day 56 (R2 = 94.42%), demonstrating a decreasing requirement for MOS with increasing lobster size. In conclusion, mannan oligosaccharide supplementation appears to be effective for improving growth, survival and gastro-intestinal health of the lobster, P. homarus.

The period over which spiny lobster eggs develop varies widely and is related to incubation temperature. For the tropical rock lobster (Panulirus ornatus), this relationship is found to be: Incubation period (days)=95.444–2.482×Temperature (°C) for incubation temperatures between 24 and 30 °C. Incubation temperatures ≥32 °C are unsuitable for this species and result in the termination of egg clutches. Additionally, egg clutches incubated at lower temperatures hatched over more nights than those at higher temperatures. These findings mean that lead times to larval hatch can now be predicted for this species, allowing for preparation time prior to larval culture.

Interest in the development of aquaculture of the tropical spiny lobster, Panulirus ornatus, has increased markedly over the past 10 yr because of strong market demand and high prices. In Australia, economic conditions will necessitate that a semi-intensive approach be taken, possibly involving managed environmental conditions. Identification of optimal temperature and salinity levels will be necessary, and therefore two experiments were performed to examine these two parameters. Juvenile lobsters were grown in tanks at five temperatures (19, 22, 25, 28 and 31 C). Growth was significantly affected by temperature (P < 0.01), and maximal growth occurred at 25-31 C. Examination of the temperature effect on molt increment and intermolt period indicated that 27 C was the optimal temperature, at which molt increment was greatest and intermolt period the least. Temperature also had a significant (P < 0.01) positive effect on apparent feed intake (AFI). Juvenile lobsters were also exposed to four different salinities (20, 25, 30 and 35 ppt) over a period of 91 d. Significant differences (P < 0.01) were apparent for both survival and growth. Lowest survival occurred at 35 ppt which may be attributable to higher cannibalism at that salinity. Growth was highest at 35 ppt and progressively less at lower salinities. Although full marine salinity (35 ppt) will generate best performance of P. ornatus, its capacity to tolerate reduced salinity will provide greater opportunity to develop commercial aquaculture.

It is proposed that an athlete's overtrained state is more perceptible in its etiology, diagnosis, treatment and prevention if considered from the context of a biopsychosocial disorder of adjustment. By shifting focus from a limited notion of excessive training loads and inadequate recovery schedules onto a comprehensive model of maladjustment, the full scope of the phenomenon becomes clearer. Specifically, the overtrained state is reconceptualized as an Adjustment Disorder and thus should be treated from the perspective of this diagnosis. Adjustment Disorder is viewed as a response to an identifiable stressor or stressors that results in clinically significant symptoms, and ‘can be triggered by a stressor of any severity and may involve a wide range of possible symptoms’ (DSM-IV-TR, 2000, p. 682). A rationale for the adoption of this definition is proposed. Included in this rationale is a comprehensive model of maladjustment with an overview of relevant subtypes to clarify the complex interaction of vari...

This article raises a specific concern that is highlighted by the recent decision to raise the minimum standard for registration as a psychologist in Australia to postgraduate masters degree level. It is suggested that such an objective is limited because it does not address other, more important variables required to ensure that minimum standards for registration as a psychologist are achieved. Specifically, it is proposed that unless the existing methodology and content of both undergraduate and fourth year graduate university training for psychologists is improved to incorporate vital areas of practice, standards will continue to remain low regardless of the introduction of compulsory fifth and sixth years of postgraduate education. This article provides an overview of the issue while suggesting an alternative approach for developing professional expertise in those wishing to embark on a career in psychology.

Two experiments were conducted to assess the water stability of a practical research diet manufactured with various binders and differing levels of moisture. In the first experiment the binders – agar, gelatine, carrageenan, and carboxymethylcellulose (CMC) were included at both 3 and 5% of total ingredient weight. All binders were tested with equal ingredient weight to water volume, and additionally carrageenan was tested in a diet with double the water volume. The dry matter remaining following immersion for up to 180 min was calculated and the rate of pellet decay was modelled using the Weibull distribution. The analysis revealed that the rate of dry matter loss decreased with time, and that carrageenan and CMC binders were significantly better (P

Two lines of redclaw crayfish (Cherax quadricarinatus) were maintained for four generations. One line was selected for increased harvest weight at 9 months, and the other maintained as an unselected control. To increase the heritability and limit inbreeding, lines were subdivided into cohorts with selection based on weight differences from cohort means. Selection increased harvest weight. In generation 4, weights averaged 61.6 g for the selected line and 49.3 g for the control line (s.e. diff. 2.3). The percentage of females carrying eggs at harvest was 9.8 in the selected line and 18.1 in the control line (s.e. diff. 4.0) suggesting that selection may have diverted energy from breeding activity to growth by delaying sexual maturity. Selection increased the carapace and tail length of females relative to their body weight. Estimates of realised heritabilities for harvest weight varied from 0.38±0.06 in year 1 to 0.13±0.02 in year 4. A practical selection program for redclaw could include periods of closed line selection alternating with test crossing with outside stocks to replenish genetic variation.

An experiment was designed to assess the relative performance of several shelter types on the production of redclaw crayfish Cherar quadricarinatus under earthen pond conditions. Juvenile crayfish with a mean stocking weight of 12.76 g were cultured in 24 net pens at 12.5 m2 within a 0.2 ha earthen pond, and were provided with one of five shelter types or no shelter over 162 d. The various shelter types assessed were: mesh bundles, pipe stacks, car tires, elevated cement/fiber-board sheets, and cement/fiber-board sheets laid flat on the substrate. Crayfish in each pen were fed a formulated pellet diet three times each week. Treatments were assessed on the basis of crayfish growth, survival, harvest biomass and berry rate among females at harvest. There was no significant effect (P > 0.05) of shelter type on growth; however, there was a highly significant effect (P < 0.001) on survival with mesh bundles (75.1%), tires (51.4%), and pipe stacks (43.25%) performing significantly better than the no shelter control (15%). The consequence of equal growth and differing survival among treatments produced significant differences in harvest biomass (P < 0.01). There were also significant differences in berry rate for the different treatments (P= 0.002), and a significant negative correlation of berry rate on survival for those treatments where shelter was provided. This experiment showed that the shelter types provided during pond culture had a significant effect on harvested biomass, primarily through its effect on survival. The efficacy of the mesh bundle shelters may be attributable to the variability in the size of the spaces provided, and the ability of the mesh to separate many individuals relative to the overall volume of the shelter.

This paper provides a review and summary of strain comparison and selective breeding work carried out on redclaw crayfish Cherax quadricarinatus (von Martens) at the Queensland Department of Primary Industries, Freshwater Fisheries and Aquaculture Centre, Walkamin. Redclaw crayfish are a highly marketable, environmentally tolerant, freshwater crayfish with a moderately fast, but variable, growth rate. Five strains of the species were assessed morphologically and in terms of age at maturity. A non-replicated production trial was also carried out before two strains, from the Gilbert and Flinders rivers in North Queensland, were chosen to be part of an experimental selective breeding programme for improved growth. Initially, 14 families of each strain were randomly mated and grown out. At this point, a size-related selection took place, with the largest animals from each family forming a selected line, and individuals from around the mean forming a control line. Within-family selection and reciprocal mating between families was performed. Data were collected after each of two generations of growout and analysed by analysis of variance. Significant differences (P< 0.05) were measured between strains, sexes and between selected and control lines. Selected individuals grew 9.5% faster than the controls. Recommendations for selective breeding research involving freshwater crayfish are presented.

Manual sexing of redclaw crayfish Cherar quadricurinatus was undertaken to evaluate the feasibility of monosex culture and to establish growth and yield characteristics of single sex populations. Although the all-male population exhibited greater mean weight after 10 mo of growout, all-female and mixed sex populations achieved greater total yields due to significant juvenile recruitment. Commercial cultivation of all-male populations would be advantageous as in-pond reproduction is greatly abated, growth is superior and marketable yield is higher. Apparent sexual lability of juveniles combined with the laborious nature of manual sexing may render manual sexing unsuitable for commercial applications.