Australian Lobster Research Articles

Techno-economic feasibility analysis of microwave-assisted biorefinery of multiple products from Australian lobster shells

Commercially valuable proteins, chitin, and minerals of Australian lobster shells were successfully produced with high yields and good quality at laboratory scale using a newly developed microwave-intensified biorefinery process. This study analyses the technical and economic feasibility of upscaling the process to industrial production using a process simulation software, SuperPro Designer. Upscaling is not only technically feasible but also financially profitable regardless of producing multiple products or a single product. At a processing scale of 222.5 tons lobster shells per year (150 kg/batch), total capital investment (TCI) required for the integrated biorefinery process is US$28.3 million compared with US$7.8–12.7 million of the single product production processes. The net present value (NPV) of the integrated biorefinery process reaches US$50.7 million while those NPVs of producing protein, minerals or chitin only are US$30.9 million, US$27.7 million, and US$26.4 million respectively, with all under 2.6 years for the payback time. Sensitivity analysis of the integrated process demonstrated that raw material cost and product price have significant impacts on profitability. The production process is still profitable at the cost of lobster shells up to US$10 per kg and the product selling price down to 25% of the proposed market prices.

Impacts on CPUE from vessel fleet composition changes in an Australian lobster (Jasus edwardsii) fishery

ABSTRACTThe Australian Victorian Western Zone rock lobster fishery is assessed using standardised catch-per-unit-effort (CPUE). Nominal CPUE declined over 1978–2009, but this underrepresents the estimated decline in abundance, and since 2009 standardised CPUE rose notably less than nominal CPUE. This study identified vessel as a key factor that explains the discrepancy between nominal and standardised CPUE. The composition of the fleet changed since 2009, under the pressure of constraining total allowable catch quotas, with vessels exiting the fishery having substantially lower estimated catchability, which increased the average catchability of the remaining fleet. New diagnostic indices were constructed to quantify discrepancies between trends in nominal and standardised CPUE that assisted in identifying periods during which both catchability and fleet composition changed.

Overview, opportunities and outlook for Australian spiny lobster fisheries

Australia’s lobster fisheries are relatively small in volume (9500t) compared with global production (289,000t), but are the country’s most valuable in terms of both overall production and value of export (2014 Gross Value of Production of $610 million AUD). Further, they support commercial, recreational and indigenous fishers along most of the continent’s coastline. Here we review similarities and key differences between these lobster fisheries, based on biological characteristics, fishery data collection, assessment and management methods, and supply chain considerations. A diverse range of palinurid lobsters occur in Australia, but only three genera, distributed across eight different management jurisdictions, support significant fisheries. Catches of western rock lobster Panulirus cygnus dominate landings (61%), followed by southern rock lobster Jasus edwardsii, tropical lobster Panulirus ornatus and the eastern rock lobster Sagmariasus verreauxi. Large-scale environmental influences such as climate change are impacting on these fisheries in similar or different ways forcing new management and raising the need for greater resilience in current supply chains. Although these are separate fisheries, the integrated nature of the dominant Chinese export markets suggests potentially important economic and market-related interactions. Our overview highlights the critical role of continued monitoring of recruitment pulses, in combination with robust harvest strategies, to ensure that harvests respond adequately and fisheries achieve biological and economic sustainability. Approaches that also include socio-cultural considerations (triple bottom line) are important given many fisheries include indigenous Australians. Our integrated analysis of Australian lobster fisheries highlights differences and similarities with spiny lobster fisheries worldwide and lessons from opportunities, including adapting to new free trade agreements, enhancing the reputation of wild lobsters as a whole, sharing expertise, and better alignment of supply and demand.

Price integration in the Australian rock lobster industry: implications for management and climate change adaptation

Rock lobster fisheries are Australia's most valuable wild fisheries in terms of both value of production and value of exports. Different states harvest and export different lobster species, with most of the landings being sent to the Hong Kong market. A perception in the Australian lobster industry is that the different species are independent on the export market, such that a change in landings of one species has no impact on the price of the others. This study investigates the market integration of Australian exports to Hong Kong for the four species and different exporting states. Our results indicate all four species and producers/export states are perceived to be substitutes for one another, so that, in the long run, prices paid to operators in the industry will move together. The integrated nature of the Hong Kong export market for Australian lobster suggests that the potential impacts of alternative fisheries management and development strategies at state and species levels cannot be considered in isolation, at least from an economic perspective. In addition, impacts of external shocks affecting production in one state (e.g. climate change) can be expected to affect all Australian lobster fisheries.

Integrating recapture-conditioned movement estimation into spatial stock assessment: A South Australian lobster fishery application

The practical aim of this study was to estimate biomass in two subregions, inshore (<60 m depth) and offshore (>60 m), for application to rock lobster management. To account for lobster movement between these subregions, movement estimation was integrated into the length-structured stock assessment model. Tagged lobsters were released inshore and offshore in the mid-1990s. For fitting to these conventional single tag-recoveries, a recapture-conditioned movement rate estimation method was adapted and integrated into the assessment model. The individually-tailored probabilities of survival during time-at-large and of subsequent capture in each subregion needed to estimate movement rates are provided by the over-arching stock assessment estimator. Calculating a probability specific for each lobster recapture permits the estimator to account for naturally varying times and locations of tag release and recapture. Seasonality of tagged lobster movements indicated that inshore-to-offshore migration occurred predominantly in winter. Yearly movement rates of lobsters were relatively low. Biomass was approximately 3–4 times higher inshore than offshore. Testing using simulated data confirmed the accuracy of model-integrated recapture-conditioned movement estimates. Using these same simulated data, conventional movement rate estimates, calculated as raw proportions of recaptured lobsters that moved, were positively biased. Incorporating survival and recovery rates in movement estimation can thus substantially improve the accuracy of movement, and thus biomass, estimates in spatially-resolved stock assessments.

The South Australian lobster fishery management model

Modelling the rock lobster ( Jasus edwardsii) fishery in South Australia was the focus of a three-year data gathering program. In collaboration with fishers, a tool for assisting in the sustainable management of the resource was developed. The goal was to test management policies to allow increases in reproductive output while enhancing economic yield. The model's user interface was developed to an ease of use comparable to commercial software for use by fishers in comanagement of the resource. This paper describes the modelling framework, user interface, and results for management strategies under consideration. The framework is comprised of five principle submodels: catch, effort, growth, economics, and population reproduction, with the lobster population divided into 8 mm length classes by sex and spatial cell. The mortality of lobsters occurs by commercial harvest, natural mortality, incidental release mortality, predation inside pots before retrieval, illegal harvesting, and recreational catch. Five categories of management control scenario were simulated: catch quota, effort regulation (as total pot retrievals), size regulations (allowing minimum, maximum, and mid-range slice length protection), and seasonal and area closures. Model outputs imply that size strategies have limited potential compared with effort limitations and quota.

Fishery-independent surveys and stock assessment of Panulirus ornatus in Torres Strait

The Torres Strait lobster fishery differs culturally and ecologically from other Australian lobster fisheries. Ornate rock lobsters (Panulirus ornatus) have been fished by the inhabitants of Torres Strait for centuries, and commercial fishing began in the late 1960s. The fishery is a major source of income for Torres Strait Islanders, and the aim of management is to balance the needs of traditional and commercial users under a treaty between Australia and Papua New Guinea. In 1989, the absolute abundance of lobsters in the main fishing grounds was estimated by a visual census and a simple assessment was made. Since then, annual fishery-independent surveys of the relative stock abundance, and catch sampling, have contributed to the development of a simple cohort dynamics model of the fishery; for a range of fishing mortalities, it estimates the potential yield and percentage escapement and has provided annual assessments of the status of the stock and potential yield one year in advance— information valuable for managers considering development options and negotiating catch-sharing agreements and access rights. Future research will develop the model by incorporating information from ongoing surveys, catch recording, and logbook data from the Australian and Papua New Guinean fisheries.

Comparison of Phenoloxidase Activity from Florida Spiny Lobster and Western Australian Lobster

ABSTRACTPolyphenoloxidase (PPO) isolated from cuticle of Western Australian lobster (Panulirus cygnus) and Florida spiny lobster (Panulirus argus) catalyzed oxidation of catechol and DL‐β‐3,4‐dihydroxyphenyla!anine (DL‐DOPA). The PPO from Florida lobster showed a higher substrate affinity than that from Australian lobster. They both showed higher affinity for catechol than for DL‐DOPA, and optimal pH stability at 7.0. The enzymes differed with respect to activation energy and thermal stability. Electrophoretic patterns using SDS‐PAGE indicated PPO from Western Australian lobster had two isoforms while Florida spiny PPO had three isoforms. These results suggest variations in enzyme activity may contribute to differences in susceptibility to melanosis between the two species.

On "Capital-Stuffing" in Regulated Fisheries

An almost uniform experience in fisheries managed by limited-entry has been the increased use of capital by each firm. This is widely regarded as an undesirable loophole in programs to limit fishing effort. Closer examination indicates that the increased use of capital by firms is produced by at least six different incentives. Moreover, not all of these incentives are economically undesirable. The net effect of capital-stuffing is ambiguous and can only be evaluated empirically. Literature demonstrating the increased accumulation of capital by limited-entry license holders is plentiful. Examples of such fisheries include the Pacific salmon fisheries (Pearse and Wilen 1979; Fraser 1979), the Japanese tuna fishery (Keen 1973), and the Australian lobster fisheries (Meany 1978). Economists have almost universally bemoaned the capital-stuffing. Capital-stuffing, they argue, occurs only because the property rights to the limited-entry license are poorly designed. The destructive forces of open access have been transformed from attracting too many firms to attracting too much capital per firm. Perhaps because economists find the microeconomic foundations of the argument so obvious, they have produced only one careful analysis of the causes of capital-stuffing. Anderson (1976), applying the classical Ushaped long-run average cost curve, argued that limited entry will increase marginal revenue per unit of effort, and hence, encourage the firm to expand its size. Anderson assumed effort to be an intermediate good that is pro-