Total Allowable Commercial Catch Research Articles

Adapting to climate change in a spiny lobster (Jasus edwardsii) fishery: A harvest strategy response

The complex lifecycle of spiny lobsters makes the species particularly vulnerable to the impacts of climate change. In south-eastern Australia, a regime shift in productivity was experienced during the late 1990s with evidence indicating that increased water temperatures had impacted on female size-of-maturity. Within the Southern Zone fishery of South Australia, this translated into low levels of egg production and sub-optimal fishery performance. In 2018, the harvest strategy for the fishery was reviewed with the primary focus of achieving a target percentage of unexploited egg production (%UEP) within an agreed timeframe. The proposed harvest strategy was based on a tabular harvest control rule, where catch per unit effort (CPUE) from the preceding season, as an indicator of lobster abundance, specified the following year’s total allowable commercial catch (TACC). To account for climate change impacts, the harvest strategy was assessed using a projection model where recruitment was sampled from post-regime shift years, thereby adopting a conservative approach to stock rebuilding. Results were assessed against projected trends in catch, CPUE and %UEP. In 2020, this harvest control rule was formally adopted and is now used in annual TACC setting. Observed values for key indicators have been closely aligned with projected estimates, with %UEP estimates approaching the target reference point. Specifically, %UEP has improved from 10% to 15% with the target projected to be achieved by the late 2020 s. Projections are sensitive to recruitment however, with a 21% lower recruitment scenario failing to reach target levels, thereby reinforcing the need to account for climate change impacts in harvest strategy testing.

“Fishing Smart”: Bioeconomic Optimization of Fishing Strategies in an Australian Mollusk Fishery

AbstractRecent declines in the biomass of wild abalone populations around Australia are leaving fisheries with low catches, declining profitability, and an uncertain future. Using the abalone fisheries in the western zone of South Australia, we investigate ways to help mitigate these changes by “fishing smart.” We use a two‐pronged approach to demonstrate (1) considerable benefits to fishing abalone during specific months of the year and (2) that fishing profitability can benefit considerably from fleet rationalization. This was achieved by (1) using the seasonally variable biology of abalone to increase fishing efficiency and (2) analyzing the economic benefit of reducing fleet size and fishing season. We demonstrate that profitability can be improved by changing the timing of fishing and amending fleet size as the total allowable commercial catch changes. We show that information on the seasonally variable biology of greenlip abalone Haliotis laevigata and blacklip abalone H. rubra can be used to increase net economic return, reduce exploitation rates, or achieve a combination of these two management objectives. The outputs identify clear economic and biological benefits to altering monthly fishing effort for both species. A cost–benefit analysis contrasted restructure scenarios that involved combinations of changes in fishing season and fleet size with a status quo baseline.

Introduction of spatial management in a temperate abalone (genus Haliotis) fishery: What can be learned from spatial variability in catches?

AbstractExploited abalone (genus Haliotis) populations are prone to serial depletion and stock collapse. Spatial management units (MUs) aim to separate monitoring and management of meta‐populations with varying productivity. In the South Australian Southern Zone blacklip abalone (Haliotis rubra rubra, Leach) fishery, spatial terms at scales of kilometres (reporting areas, RAs) and tens of kilometres (MUs) explained a greater proportion of variability in daily catches than effort in linear mixed models. Temporal patterns in spatial structures of catches among RAs were consistent with those among MUs based on similar productivity. Results of this study support the hypothesis that changes in the spatial distribution of catches differs among management regimes based on minimum legal lengths (MLLs) and annual total allowable commercial catches (TACCs). Stable distribution of catches during 1992–2012 occurred contemporaneously with zonal TACCs combined with catch caps (sub‐TACCs) and MLLs applied to areas of low productivity providing a reference for future management. The number of MUs fished annually by each licence increased during this period. Results of this study suggest that successful spatial management of abalone fisheries requires MUs at scales based on biological productivity combined with MLLs and mandatory, conservative catch caps applied to each MU.

Diving into fisher experience: Do new entrants and fleet turnover depress catch rates in abalone (Haliotis laevigata and H. rubra) fisheries

A fisher’s experience may provide greater efficiency and enhanced catches through time. Compared to new entrants to the fishery, experienced fishers often have developed tactics: the advantage of knowing ‘the best’ fishing grounds, having established efficient fishing practices, and developing relationships and trust within their fishing community. The influence of experience on catch rates, a key indicator of abundance, may be particularly strong in fisheries such as abalone, which rely on hand-collection and local knowledge for catches. We investigated diver records for greenlip (Haliotis laevigata) and blacklip (Haliotis rubra) abalone fisheries in South Australia to 1) examine annual catch rates (CPUE) and the number of diver entrants among licenses, 2) determine if CPUE of new diver entrants is lower than average fleet CPUE, and 3) establish relationships between CPUE and experience. We additionally simulated fleet turnover in the South Australian Western Zone Abalone Fishery by randomly replacing 25 %, 50 %, and 75 % of daily CPUE records with new diver catch rates and applied decision rules in the proposed abalone harvest strategy that allow for, and if needed account for, the impacts of new divers on catch rates. Catch rates varied among licenses and, on average, each license had less than one diver entrant per year (i.e., on average 5–20 % fleet turnover). During the first three years post-entry, annual license catch rates were generally 3–10 % lower than fleet catch rates, and license CPUE was positively correlated to experience in both greenlip and blacklip fisheries. However, depressed catch rates of entrants were unlikely to impact fleet trends given the small proportion of new entrants annually, and in cases where new divers impact CPUE, the proposed harvest strategy enables adjustment of recommended catches at a fine spatial scale prior to calculating the total allowable commercial catch. Of greater concern is ≥ 50 % fleet turnover, which, during simulations of the Western Zone Fishery, depressed fleet CPUE by ∼1 kg/hr or more; a reduction that is sufficient to result in lower recommended catches and, if such exceptional circumstances were to occur, may require modification of harvest strategy application. Assessing fisher experience as a driver of catch rate, builds a greater understanding of primary indicators for stock assessment and, together with appropriate decision-making tools, provides a more reliable management outcome.

Comparison of financial performance of Japanese and Australian small scale tuna longline fisheries

Two small scale tuna longline fisheries, the Japanese Small Offshore Tuna Longline fishery (SOTL) and the Australian Eastern Tuna and Billfish Fishery (ETBF) have much in common, including: gear, target species and the relatively small scale entities, whereas they have large differences in their respective management strategies (the ETBF is output controlled whereas the SOTL is input controlled) and the distance between the point of catch and the point of landing (SOTL fishes far beyond Japan's EEZ, ETBF concentrates within Australia's EEZ). This study focuses on the financial performance of the SOTL and the ETBF between 2011 and 14. The ETBF performs better on financial performance compared to the SOTL but has a higher “per hook fishing cost” due mainly to lower fishing effort (i.e. number of hooks) deployed. This contrasts with the situation pertaining in a previous bio-economic model study of longline tuna fisheries in the WCPO. Periodic updates of the “per hook fishing cost” will enable improvements of accuracy of the bio-economic modelling. We conclude that better catch rate and less fuel consumption compared to the SOTL is the primary reason that the ETBF performs better profitability. We assumed that the rights-based controls including Individual Transferable Quotas (ITQs) under the Total Allowable Commercial Catch (TACC) of the ETBF supports to maintain a higher catch rate and lower fuel consumption compared with the SOTL where resource rights are not allocated to vessels. This analysis lends weight to suggestions that an appropriate rights-based allocation system will improve profitability of tuna longline fisheries.

High levels of site fidelity in movement patterns of Southern Rock Lobster (Jasus edwardsii) in Victoria, Australia

ABSTRACT Movement patterns of the Southern Rock Lobster Jasus edwardsii in Victoria, Australia were investigated from 8,533 tag-recapture events across a 20-year period (1992–2012). In total, 83% of lobsters were recaptured within 1 km of their tagging site and 93% within 5 km. While largely resident, elevated movements were observed within specific regions, with the overall direction of movement being from inshore to offshore areas. Movement was not impacted by lobster sex, size, or reproductive stage. The fishery for Southern Rock Lobster within Victoria is currently managed into two zones with separate total allowable commercial catches in each area. Given the high levels of site fidelity, our findings suggest that management of the resource at this spatial scale is appropriate and that consideration of significant movement between zones is not warranted in fishery stock assessment models.

Modelling trends including effects of natural disturbance in an abalone dive fishery in Australia

AbstractFisheries management strategies usually do not consider secondary consequences of environmental shocks. A recent viral disease outbreak that decimated blacklip abalone populations in southern Australia had a much smaller impact on the region's less‐abundant greenlip abalone populations. Decreases in total allowable commercial catch (TACC) for blacklip abalone were partially offset by a transient increase in greenlip abalone TACC that peaked in 2010 and reduced to zero in 2013. A hypothesis that the greenlip abalone stock had declined was supported by a Bayesian analysis of catch rates (catch per unit effort, CPUE, as a proxy for biomass). The estimated decline is consistent with depletion of the relatively small and fragmented greenlip stock as an indirect consequence of the disease impact. Our analysis demonstrates a need to jointly monitor and manage substitute fisheries when one of the fisheries experiences depletion as a result of a natural disturbance event.Considerations for Management Hierarchical Bayesian models can determine whether a shock to a natural resource indirectly affects related resources via a transfer of exploitation effort; Greenlip abalone stocks in western Victoria were generally poor in quality and infrequently exploited prior to the disease outbreak. Their low productivity rendered them vulnerable to the sudden increase in exploitation pressure, which could not be sustained once CPUE declined to 40–50 kg h−1, after which fishing activity ceased; A CPUE of 40 kg h−1 could be a precautionary limit reference point for triggering future greenlip abalone fishery closures; An increase in greenlip abalone legal minimum length (LML) to at least 140 mm would improve quality and profit; It is important to protect substitute resources from secondary exploitation when imposing restrictions on exploitation of resources that are adversely impacted by natural disturbance events.

Ecosystem-based fisheries management (or ‘triple bottom line’) assessments of the western rock lobster resource: Is there an optimal target for fishing?

Ecosystem-based fisheries management (EBFM) is often termed triple bottom line because it takes into account ecological, economic and social criteria. Effective implementation of EBFM requires development of appropriate governance structures for decision-making processes and management, so governance effectiveness and efficiency can be regarded as the fourth element in a ‘quadruple bottom line.’ Few fisheries have explicitly considered all four criteria within their resource assessments and harvest strategies. Furthermore, as some of these objectives may be in competition (e.g. employment levels, profit), a simultaneous evaluation of these criteria is required to identify the optimal level of fishing to deliver the best overall community outcome.The western rock lobster, Panulirus cygnus, resource in Western Australia is used as an EBFM case study by evaluating: sustainability of target species and effects on ecosystem and protected species; economics of the fishery; effect on employment, coastal communities and quality of recreational fishing; and governance effectiveness including explicit sectoral catch allocations, and the efficiency of monitoring and compliance systems.In 2010 the fishery moved from effort-controlled maximum sustainable yield (MSY) to a quota-controlled, maximum economic yield (MEY) system. This study explicitly examined how different levels of harvesting across the MSY to MEY range affected each of ten EBFM criteria. We confirmed that these individual objectives were maximised at different total allowable commercial catches. However an example is provided for weighting of objectives from a possible management perspective that identified the upper end of the MEY range as likely to generate the optimum outcome for this fishery.

Fishing without quota: The ACE fisher in New Zealand's inshore fishery

The annual catch entitlement (ACE) scheme was added to New Zealand's quota management system for fisheries in 2001. The scheme allocates quota owners an annual share of the total allowable commercial catch (TACC) in proportion to their quota holding of a particular fishstock. With ACE being transferable, the change made it simpler for fishers (permit holders) who did not own quota to purchase ACE to match catch for specific fishstocks. But to be viable, non-quota-owning (ACE reliant) fishers need access to a reliable, long-term supply of ACE. This study examines the relationships between ACE reliant purchasers and their suppliers of ACE in New Zealand's Fishing Management Area Three during the 2014-15 fishing year. The study found that most buyers and sellers of ACE form enduring relationships to their mutual benefit. This symbiotic relationship bodes well for the survival of small fishers with the expertise to land fish in an efficient manner.

Decision rules for quota setting to support spatial management in a lobster (Jasus edwardsii) fishery

The Northern Zone rock lobster fishery in South Australia is extensive, covering ca. 207 000 km2. Managed under transferable quotas, the majority of the annual total allowable commercial catch (TACC) is taken on eastern inshore grounds, targeting the smaller redder lobsters favoured by Chinese buyers. The confined nature of fishing under the TACC system has led to concerns of localized spatial depletion and suggested a need for spatial management. A regional partition of the TACC was proposed. Formal prescriptive decision-rule tables for setting regional TACCs annually were constructed based on target exploitation rates. A target exploitation rate of 20% historically produced zero average yearly change in biomass and, in previous bioeconomic projection modelling, achieved near-optimal net economic return. Using an age-based fishery assessment model that fits to catch totals by both weight and number landed, conditioning on fishing effort and mean weights-at-age, we estimated harvestable biomass for three regions. The management response was to establish inner and outer subzones where separate TACC decision rules are now adopted. Basing the harvest strategy on a target exploitation rate underlies a simple direct method for constructing decision-rule tables for setting TACC using the indicator of previous year’s catch per unit effort (cpue). In the normal cpue range, a constant target exploitation rate is applied. At lower levels of stock abundance, below a designated upper limit reference point of cpue, the exploitation rates used to assign TACCs are set to decline linearly from the normal target level, reaching zero at a designated lower-limit reference cpue point below which the fishery is closed. At higher levels of cpue, stakeholders agreed to a TACC cap, under which exploitation rate decreases if biomass rises. This case study applies where formal harvest strategy decision rules for quota-based lobster fisheries are considered at finer spatial scales.

Using bioeconomic modeling to improve a harvest strategy for a quota-based lobster fishery

In Australian fisheries, explicit harvest control rules are increasingly applied to achieve bioeconomic objectives. Enhancing economic return, an objective valued by both regional communities and the fishing industry, can often be achieved by increasing stock abundance, consequently supporting the second principal management objective of sustainability. A harvest strategy proposed by the fishing industry for the Southern Zone rock lobster fishery in South Australia implemented in 2011 was based on a table that, given CPUE from the preceding season, specified the following year’s catch quota (total allowable commercial catch, TACC). A guiding principle in constructing the 2011 harvest control rule was to target a constant exploitation rate. Here we report on bioeconomic modeling undertaken to evaluate and improve this harvest strategy. A length-based stock assessment model was extended to forward project biological and economic time series to evaluate candidate harvest strategies. Key performance indicators were the 10-year projected discounted profit, biomass, egg production and catch stability. These simulations imply that the 2011 harvest strategy required only moderate change: (1) current or moderately lower levels of exploitation are economically optimal; (2) narrower CPUE band widths for the TACC-vs-CPUE decision rule table enhance yearly catch stability; and (3) for depressed levels of stock abundance, exploitation rates were set to decrease linearly down to a lower limit reference point of CPUE below which the fishery is closed. A final harvest strategy incorporating these features was adopted in 2014 for yearly quota setting.

New Zealand's ecosystem approach to fisheries management

AbstractIn 1986, New Zealand introduced a radical new quota management system (QMS) based on individual transferable quotas (ITQ) for most of its key fisheries. New Zealand's QMS focuses primarily on the management of individual fish stocks through the setting of total allowable catches (TAC) and total allowable commercial catches (TACC, allocated as ITQ) and is therefore essentially a single species‐focussed system. However, New Zealand's Fisheries Act 1996 is designed to ‘provide for utilisation while ensuring sustainability’ and the obligation to ensure sustainability has led to the introduction of many measures to deal with: incidental captures of protected species (primarily marine mammals and seabirds); benthic effects caused by bottom trawl and dredge gear; changes to marine biodiversity; and the protection of habitats of particular significance for fisheries management. Together with directed fish stock management, these measures could be considered to constitute a first‐level ecosystem approach to fisheries management. Many authors have advocated incremental or evolutionary approaches to the implementation of ecosystem approaches, and this paper summarizes developments in New Zealand since 1986 that build on the success of the QMS in this way.

Deemed value arbitrage in the New Zealand annual catch entitlement market

New Zealand's Quota Management System (QMS) consists of a two tier operational structure: Quota shares in a fishstock provide an Annual Catch Entitlement (ACE) of the total allowable commercial catch (TACC) of the specific fishstock. Fishers operating in a multispecies fishery need a portfolio of ACE that matches the mix of their annual catch. Fishers may own quota shares, and thereby receive the needed ACE allocations or they may operate without quota shares and rely on acquiring ACE in the ACE market. Whatever the fisher's situation, it is common for fishers to both buy and sell ACE during a fishing year as they seek to balance their actual catch against ACE. The incentive to achieve a balance is strong because at year-end fishers whose catch exceeds ACE are required to pay a fee called ‘deemed value’. For many fishstocks the deemed value fee increases sharply as the percentage by which a fisher's catch exceeds their ACE increases. When no ‘unbalanced’ ACE is available for purchase, an overfished fisher may attempt to mitigate their deemed value liability by engaging in arbitrage trading in ACE whereby they buy ACE from other overfished fishers. This study examines the nature and extent of ACE arbitrage behaviour in the New Zealand quota managed fishery. The study finds that the number of fishstocks where arbitrage trading occurs is relatively small and is declining. However, sizeable deemed value mitigation transactions are still evident.

Recovery of a Surf Clam Donax deltoides Population in Southern Australia: Successful Outcomes of Fishery‐Independent Surveys

AbstractEstimates of biomass or relative biomass are required for monitoring the recovery of depleted bivalve resources and for the management of newly exploited resources. Uncertainty around fishery catch per unit effort (CPUE) as a proxy for biomass highlights the need for fishery‐independent assessments. Following a prolonged period of decline in Australia's largest fishery for surf clam Donax deltoides, robust estimates of biomass were required to monitor recovery and to set appropriate total allowable commercial catches. Estimates of relative biomass were derived from fishery‐independent surveys (FIS) conducted cooperatively by researchers and fishers. The FIS assessed both the spatial (m to km) and temporal (months to years) dynamics of the fishery and enabled comparisons with CPUE. Concurrent size‐frequency distributions provided information on the mechanisms underlying variability in resource status across the fishery. Increasing relative biomass and complexity of size structures indicated recovery of the resource from 2009, although spatial contraction of the resource also occurred. Relative biomass from FIS provides a robust fishery performance indicator that is appropriate to the scale of the fishery and has advantages over fishery‐dependent CPUE of finer temporal and spatial resolution and consistent sampling efficiency. Performance indicators based on FIS provide improved understanding of the changes in resource status. Active engagement of fishers contributes to enhanced economic and environmental outcomes.Received December 9, 2014; accepted September 3, 2015

Pilot California Spiny Lobster Postlarvae Sampling Program: Collector Selection

Lobster (infraorder Astacidea) is perhaps the most intensively studied shellfish around the world due to its economic importance (Phillips 2006). Fishery management tools almost universally include catch reporting, but fishery-dependent data such as this often fails to adequately inform managers about the true state of the population (Erisman et al. 2011). Increasingly, fishery-independent surveys are being relied upon to provide the robust information fishery managers require, such as the California Cooperative Oceanic Fisheries Investigation (CalCOFI). The CalCOFI program attempts to understand and predict variations in the Pacific Sardine (Sardinops sagax) fishery, among others, in California through quarterly sampling of fish larvae and other biological and hydrographic data. This focus on larval stages stems from Hjort’s seminal work in 1914, which hypothesized the recruitment and transition of larval forms into postlarval and juvenile life stages is a critical period in population dynamics (Houde 2008). In modern times, fishery management agencies expend significant effort towards cataloging and understanding recruitment levels and patterns which provide the foundation for most fishery management tools (e.g. stock assessments). Recruitment monitoring is at the core of many of global lobster fishery management programs (Cruz et al. 1995; Acosta et al. 1997; Cruz and Adriano 2001; Phillips et al. 2005; Phillips and Melville-Smith 2005; Phillips et al. 2006; Arteaga-Rios et al. 2007; Phillips et al. 2010). Recruitment monitoring of numerous lobster taxa globally have been well correlated with future catch-rate predictions, typically with a 4 to 5 year time lag (e.g. Gardner et al. 2002; Caputi and Brown 2011; Linnane et al. 2014). Long-term recruitment monitoring programs, such as that in Australia (Linnane et al. 2010), are vital in assessing future stock levels and setting the total allowable commercial catches. Like many lobster species, the California Spiny Lobster (Panulirus interruptus) is an economically important fishery species, supporting one of California’s most valuable fisheries with annual ex-vessel values exceeding $9 million (Porzio et al. 2012). However, unlike many of the world’s lobster fisheries, no California Spiny Lobster recruitment monitoring program exists. Recent attempts to address this data gap have been made using plankton collection (Koslow et al. 2012) and power plant entrapment records (Miller 2014). Plankton collections were unable to reliably predict recent landings while entrapment records were more successful, but both articles noted the likely effect of unknown recreational harvest levels impacting the analyses and final conclusions. While informative, neither existing program fulfills the need for targeted information on California Spiny Lobster recruitment in southern California. Furthermore, as southern California power plants shift away from once-throughcooling, lobster entrapment data may soon be unavailable, in which case no regular abundance estimates of California Spiny Lobster postlarvae will be available. Noting the clear need for lobster recruitment monitoring in California, a pilot program was initiated in Orange County, California with the hopes of establishing a model that Bull. Southern California Acad. Sci. 113(3), 2014, pp. 180–186 E Southern California Academy of Sciences, 2014

In pursuit of maximum economic yield in an ITQ managed lobster fishery

A bioeconomic analysis of the Tasmanian rock lobster Jasus edwardsii fishery was conducted using a length- and sex-structured population dynamics model. This model was also spatially- and temporally-structured to account for differences in costs of fishing and prices as well as differences in abundance and productivity among regions within the fishery. The current total allowable commercial catch (TACC) was found to be higher than the level that would maximise economic yield, and this left the industry vulnerable to temporal changes in productivity. Alternative pathways to lower TACCs were explored, but these had less effect on economic yield than the final TACC. The TACC did not move towards MEY through normal decision-making based on biological stock assessments despite the fishery operating under individual transferable quota (ITQ) management for over a decade. This is because industry and government have struggled to accept that economic yield and asset values could increase with lower catches. Bioeconomic analysis assisted in debate on decreasing the TACC, suggesting formal economic analysis is required for effective ITQ management.

The importance of conserving recruitment pulses in rock lobster (Jasus edwardsii) fisheries where puerulus settlement is low or highly sporadic

The commercial fishery for southern rock lobster (Jasus edwardsii) is South Australia's most valuable fishery resource worth in excess of AUS$100 million annually. Over the past decade, recruitment to the fishable biomass has decreased, which has translated to declines in commercial catch rates. In the Northern Zone fishery, catch per unit effort (CPUE) declined from 1.42 kg/potlift in 1999 to 0.67 kg/potlift in 2008, a decrease of 52%. Puerulus monitoring has been undertaken since 1996, with the period from settlement to recruitment estimated at ~4 years. In 2002, 2005 and 2006, spikes in settlement were recorded, which were predicted to enter the fishery as recruitment pulses in 2006, 2009 and 2010, respectively. Management decisions failed to conserve the 2006 recruitment pulse by setting total allowable commercial catches (TACCs) above actual catch estimates. However, in 2008, a conservative management approach was adopted with the TACC reduced from 470 to 310 t despite 403 t being landed in the 2008 season. In 2009, CPUE increased by 31% to 0.88 kg/potlift while fishing effort decreased by 42%. In 2010, CPUE increased further to 1.07 kg/potlift, the highest since 2000. The study highlights the importance of management decisions that conserve recruitment pulses in order to sustain lobster resources on which fisheries depend.

Recovery of the eastern rock lobster Sagmariasus verreauxi off New South Wales, Australia

Catch per unit effort in the fishery for eastern rock lobsters peaked in 1971–72 and then declined until 1992–93. In response to this pattern, a management package consisting of individual catch quotas, restricted entry and a legal maximum length was imposed upon the fishery. The effectiveness of these management measures to rebuild the eastern rock lobster population has been monitored annually through data collected from surveys of puerulus larvae abundance, fishery independent surveys, a compulsory logbook, observer surveys and biological studies. The total allowable commercial catch (TACC) is set annually by the TAC Committee after considering submissions from the public and industry and an annual report for the lobster fishery. The annual report prepared by government consists of an appraisal of the performance of the fishery against the objectives of the share management plan and goals of the fishery management strategy for the rock lobster fishery and includes a formal stock assessment. The trigger points behind the objectives and goals relating to the status of the stock have not been activated in the 2010–11 year. Total biomass and exploitable biomass have increased, spawner biomass has increased to now be above 25% of the pre-exploited biomass and the relative abundance of recruits (puerulus larvae) to the population is increasing. The stock is considered to be rebuilding and the resource now supports a viable fishery with an increasing share price.

Fifty Years of Sustained Production from the Australian Abalone Fisheries

The sustained production of abalone from the five state-managed (Tasmania, Victoria, South Australia, New South Wales, and Western Australia) Australian abalone fisheries has contrasted with many of those elsewhere that exhibited rapid and sustained declines in production. Australian abalone fisheries are significant at local, regional, state, national, and international scales. Key attributes are (1) harvesting, processing, and reinvestment of profits occur away from major metropolitan centers; (2) they are among the most valuable wild-catch species in all states; (3) the combined Australian abalone harvest in 2011 (>4,500 t) had a landed value of ∼AU$200M and represented 15% of the Australian total wild-catch production; and (4) this level of production made these fisheries the dominant contributor (60%) to global wild-catch abalone production. Unlike many other abalone fisheries, total catches were controlled by limited entry, quotas, size limits, and geographic boundaries, overseen by stringent compliance regimes, early in their history. Subsequently, state-based research programs, explicitly tasked with providing scientific advice to support management decisions, undertook assessments to match harvests with stock productivity. This information upon which to base management decisions contributed to long-term (>20 years) stable harvests and enabled relationships among stakeholders to develop around consideration of the information and advice for management. In general, rights-holders developed stewardship for the resource, and this has led to numerous important outcomes, including evolving resource co-management and a nationally representative industry entity, the Abalone Council of Australia. The Abalone Council of Australia, state-based industry entities, and ongoing relationships among rights-holders, fishery managers, and researchers play vital roles in addressing and overcoming current and impending challenges for these fisheries. These difficulties include (1) urban encroachment into coastal regions (the so-called “sea change” phenomenon); (2) a growing interest in access to the abalone resource, reflecting the increasing, culturally diverse Australian population; (3) the ever-present threat of illegal fishing; (4) recent total allowable commercial catch reductions, particularly in Victoria and New South Wales, to facilitate stock rebuilding; (5) changing market conditions; (6) declining profitability from increasing operational costs and appreciation of the Australian dollar; and (7) environmental changes, such as prolonged drought and warmer seas associated with shifts in climate. Overall, this review demonstrates that abalone can be harvested sustainably over extended periods, despite aspects of their demography that suggest higher vulnerability to overexploitation, providing the management systems that control harvesting activities and external impacts that encompass several key underpinning elements. This review also identifies likely challenges to sustained production and shows that the future of these stocks and fisheries will require proactive strategies to mitigate current threats to sustainability and to maintain economically viable productivity.

Evaluating empirical decision rules for southern rock lobster fisheries: A South Australian example

The fishery for rock lobsters in South Australia's southern zone has been in decline for several years. Previous harvest strategies included limit reference points, but did not specify explicit total allowable commercial catches (TACCs) when these reference points were breached. Two alternative catch-rate-based decision rules for setting TACCs for this fishery were proposed by stakeholder groups, including government scientists and the fishing industry. The two decision rules (“discrete” and “linear”) set TACCs based on changes in catch-rates, with the general aim of achieving a constant exploitation rate. The two rules differed in terms of how TACCs are changed given changes in catch-rate. Management strategy evaluation is used to evaluate these decision rules. The “discrete” rule leads to greater variation in catches, but to somewhat lower risks. However, unlike the linear rule, the discrete rule cannot reduce [or increase] catches markedly. Based on the trade-offs between risk and catch, as well as the need for buy-in of impacted stakeholders, the discrete rule was selected as the basis for setting TACCs for the southern rock lobster fishery for the next 3–5 years.