Performance evaluation of harvest control rules for Pacific herring management in British Columbia, Canada

Abstract Cleary, J. S., Cox, S. P., and Schweigert, J. F. 2010. Performance evaluation of harvest control rules for Pacific herring management in British Columbia, Canada. – ICES Journal of Marine Science, 67: 2005–2011. Despite application of a harvest control rule (HCR) since 1986, abundance of several Pacific herring (Clupea pallasi) stocks in British Columbia, Canada, are currently below levels considered adequate for exploitation. An alternative HCR, based on default limit and upper stock reference (USR) points at 0.4 BMSY and 0.8 BMSY, was recently developed under Canada's precautionary fisheries management policy. We simulated the Pacific herring fishery management system to examine whether (i) realized fishery performance over the past 10 years is an expected consequence of applying the existing herring HCR (with a single lower reference point) and (ii) performance could be improved by adopting the Department of Fisheries and Oceans new HCR with limit and USR points. Both HCRs successfully rebuilt stocks to sustainable levels under a high-productivity scenario, but performed poorly when stock productivity was low. The two HCRs were sensitive to stock productivity, because the effect of a target harvest rate (20%) that is independent of productivity was much larger than the effects of biomass reference-point choices. We therefore recommend further research on estimating reference points and sustainable harvest rates for Pacific herring, so that HCRs may be made more responsive to changes in productivity.

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Can we fish on stocks that need rebuilding? Illustrating the trade-offs between stock conservation and fisheries considerations

10.1101/2021.02.25.432880 ◽

2021 ◽

Author(s):

Vanessa Trijoulet ◽

Casper W Berg ◽

Claus R Sparrevohn ◽

Anders Nielsen ◽

Martin A Pastoors ◽

...

Keyword(s):

North Sea ◽

Reference Point ◽

Reference Points ◽

Lower Probability ◽

Medium Term ◽

Short Term ◽

Fish Stocks ◽

Control Rules ◽

Trade Offs ◽

Harvest Control Rules

In the Northeast Atlantic, advice for many fish stocks follows the ICES MSY approach, where a zero catch will be recommended if the stock is below its limit reference point, Blim, and cannot rebuild in the short-term. However, zero catch advice are rarely implemented by managers. This study used medium-term stochastic forecasts with harvest control rules (HCRs) to investigate the consequences of allowing reduced fishing below Blim. We applied the method to western Baltic herring and North Sea cod, two contrasting species currently estimated below Blim. We show that the minimum rebuilding probability of 95% required by the MSY approach could be impossible to reach in the short-to medium-term. When this is the case, a lower probability may need to be considered instead in the short-term. Recruitment is the largest source of uncertainty in stock response to management, and can exceed differences between HCRs. Reference points should be estimated in accordance with current recruitment levels if they are to be used for short-term advice or as realistic rebuilding targets. For both stocks, it is possible to keep fishing at reduced levels for similar cumulative catch, SSB and risk on the stock in the medium-term compared to no catch below Blim. Medium-term trade-offs between stock conservation and fisheries considerations may be needed when fishery closure cannot be implemented in practice.

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The roles of biological reference points and operational control points in management procedures for the sablefish (Anoplopoma fimbria) fishery in British Columbia, Canada

Environmental Conservation ◽

10.1017/s0376892913000271 ◽

2013 ◽

Vol 40 (4) ◽

pp. 318-328 ◽

Cited By ~ 5

Author(s):

SEAN P. COX ◽

ALLEN R. KRONLUND ◽

ASHLEEN J. BENSON

Keyword(s):

British Columbia ◽

Stock Assessment ◽

Reference Points ◽

Control Points ◽

Operational Control ◽

Short Term ◽

Anoplopoma Fimbria ◽

Control Rules ◽

Management Procedures ◽

Harvest Control Rules

SUMMARYBiological reference points (BRPs) in fisheries policy are typically sensitive to stock assessment model assumptions, thus increasing uncertainty in harvest decision-making and potentially blocking adoption of precautionary harvest policies. A collaborative management strategy evaluation approach and closed-loop simulation modelling was used to evaluate expected fishery economic and conservation performance of the sablefish (Anoplopoma fimbria) fishery in British Columbia (Canada), in the presence of uncertainty about BRPs. Comparison of models derived using two precautionary harvest control rules, which each complied with biological conservation objectives and short-term economic objectives given by industry, suggested that both rules were likely to avert biomass decline below limit BRPs, even when stock biomass and production were persistently overestimated by stock assessment models. The slightly less conservative, industry-preferred harvest control rule also avoided short-term economic losses of c. CAN$ 2.7–10 million annually, or 10–50% of current landed value. Distinguishing between the role of BRPs in setting fishery conservation objectives and operational control points that define harvest control rules improved the flexibility of the sablefish management system, and has led to adoption of precautionary management procedures.

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Developing and evaluating harvest control rules with different biological reference points for the American lobster (Homarus americanus) fishery in the Gulf of Maine

ICES Journal of Marine Science ◽

10.1093/icesjms/fsr071 ◽

2011 ◽

Vol 68 (7) ◽

pp. 1511-1524 ◽

Cited By ~ 8

Author(s):

Yuying Zhang ◽

Yong Chen ◽

Carl Wilson

Keyword(s):

Gulf Of Maine ◽

Homarus Americanus ◽

The United States ◽

Reference Points ◽

Systematic Evaluation ◽

American Lobster ◽

Natural Mortality ◽

Control Rules ◽

The Status ◽

Harvest Control Rules

Abstract Zhang, Y., Chen, Y., and Wilson, C. 2011. Developing and evaluating harvest control rules with different biological reference points for the American lobster (Homarus americanus) fishery in the Gulf of Maine. – ICES Journal of Marine Science, 68: 1511–1524. The American lobster (Homarus americanus) supports one of the most valuable commercial fisheries in the United States. Controversy exists, however, in terms of the biological reference point (BRP) used in assessing lobster stock status, and there is no fully established or evaluated harvest control rule (HCR). A sex-specific, size-dependent operating model is developed to evaluate the performance of two HCRs, discrete and continuous, which adjust annual fishing mortality discretely and linearly, respectively, based on the status of the fishery. For each HCR, different BRPs are considered along with management duration, recruitment dynamics, and natural mortality. HCRs with a suitable set of BRPs can drive the fishery from an undesirable status to an optimal status. The continuous HCR tends to perform better than the discrete one. The Ftarget of 0.31 year−1 showed the best performance in the long term by balancing the needs of the fishing industry and conservation bodies. However, this was not the case in the short term. An Ntarget of 49.6 million would allow the American lobster to be maintained at its current stock level, with high recruitment and stable natural mortality. The study provides a framework for a systematic evaluation of management regulations for the American lobster.

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Linking spatial stock dynamics and economics: evaluation of indicators and fishery management for the travelling eastern king prawn (Melicertus plebejus)

ICES Journal of Marine Science ◽

10.1093/icesjms/fst218 ◽

2014 ◽

Vol 71 (7) ◽

pp. 1818-1834 ◽

Cited By ~ 9

Author(s):

Michael F. O'Neill ◽

George M. Leigh ◽

You-Gan Wang ◽

J. Matías Braccini ◽

Matthew C. Ives

Keyword(s):

Fishery Management ◽

New South ◽

Fishing Effort ◽

Reference Points ◽

Catch Rate ◽

Decision Makers ◽

Control Rules ◽

South Wales ◽

Strategy Evaluation ◽

Dynamics Calculation

Abstract Reduced economic circumstances have moved management goals towards higher profit, rather than maximum sustainable yields in several Australian fisheries. The eastern king prawn is one such fishery, for which we have developed new methodology for stock dynamics, calculation of model-based and data-based reference points and management strategy evaluation. The fishery is notable for the northward movement of prawns in eastern Australian waters, from the State jurisdiction of New South Wales to that of Queensland, as they grow to spawning size, so that vessels fishing in the northern deeper waters harvest more large prawns. Bioeconomic fishing data were standardized for calibrating a length-structured spatial operating model. Model simulations identified that reduced boat numbers and fishing effort could improve profitability while retaining viable fishing in each jurisdiction. Simulations also identified catch rate levels that were effective for monitoring in simple within-year effort-control rules. However, favourable performance of catch rate indicators was achieved only when a meaningful upper limit was placed on total allowed fishing effort. The methods and findings will allow improved measures for monitoring fisheries and inform decision makers on the uncertainty and assumptions affecting economic indicators.

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An evaluation of acceptable biological catch (ABC) harvest control rules designed to limit overfishing

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2016-0381 ◽

2017 ◽

Vol 74 (7) ◽

pp. 1028-1040 ◽

Cited By ~ 11

Author(s):

John Wiedenmann ◽

Michael Wilberg ◽

Andrea Sylvia ◽

Thomas Miller

Keyword(s):

Fishery Management ◽

Short Interval ◽

Assessment Model ◽

Scientific Uncertainty ◽

High Yield ◽

Management Objectives ◽

Control Rules ◽

Average Biomass ◽

Harvest Control Rules

In this paper we developed a simulation model to evaluate a range of acceptable biological catch (ABC) control rules to determine their relative performance at achieving common fishery management objectives. We explored a range of scenarios to determine robustness of a control rule to different situations and found that across scenarios the control rules that used a buffer to account for scientific uncertainty when setting the ABC were able to limit the frequency of overfishing. Modest buffers when setting the ABC were generally effective at limiting overfishing, but larger buffers resulted in higher average biomass, similar long-term benefits to the fishery (high yield, low variability in yield), more rapid recovery of depleted populations, and a lower risk of the population being overfished, and these results were robust to the level of uncertainty in the assessment model estimates. In addition, fixing the ABC over the interval between assessments and having a short interval between assessments was generally more effective at meeting management objectives than using projections and having a long assessment interval.

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Harvest control rules for data limited stocks using length-based reference points and survey biomass indices

Fisheries Research ◽

10.1016/j.fishres.2014.11.013 ◽

2015 ◽

Vol 171 ◽

pp. 12-19 ◽

Cited By ~ 15

Author(s):

Ernesto Jardim ◽

Manuela Azevedo ◽

Nuno M. Brites

Keyword(s):

Reference Points ◽

Control Rules ◽

Harvest Control Rules

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Implementing the precautionary approach into fisheries management: Making the case for probability-based harvest control rules

10.1101/2020.11.06.369785 ◽

2020 ◽

Author(s):

Tobias K. Mildenberger ◽

Casper W. Berg ◽

Alexandros Kokkalis ◽

Adrian R. Hordyk ◽

Chantel Wetzel ◽

...

Keyword(s):

Fisheries Management ◽

Management Strategies ◽

Reference Points ◽

Production Model ◽

Scientific Uncertainty ◽

Precautionary Approach ◽

Control Rules ◽

Stock Biomass ◽

Harvest Control Rules

AbstractThe precautionary approach to fisheries management advocates for risk-averse management strategies that include biological reference points as well as decision rules and account for scientific uncertainty. In this regard, two approaches have been recommended: (i) harvest control rules (HCRs) with threshold reference points to safeguard against low stock biomass, and (ii) the P* method, a ‘probability-based HCR’ that reduces the catch limit as a function of scientific uncertainty (i.e. process, model, and observation uncertainty). This study compares the effectiveness of these precautionary approaches in recovering over-exploited fish stocks with various life-history traits and under a wide range of levels of scientific uncertainty. We use management strategy evaluation based on a stochastic, age-based operating model with quarterly time steps and a stochastic surplus production model. The results show that the most effective HCR includes both a biomass threshold as well as the P* method, and leads to high and stable long-term yield with a decreased risk of low stock biomass. For highly dynamics stocks, management strategies that aim for higher biomass targets than the traditionally used BMSY result in higher long-term yield. This study makes the case for probability-based HCRs by demonstrating their benefit over deterministic HCRs and provides a list of recommendations regarding their definition and implementation.

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Cognitive Reflection Effects on Time Discounting

Journal of Individual Differences ◽

10.1027/1614-0001/a000254 ◽

2018 ◽

Vol 39 (2) ◽

pp. 99-106 ◽

Cited By ~ 4

Author(s):

Michał Białek ◽

Przemysław Sawicki

Keyword(s):

Individual Differences ◽

Individual Difference ◽

Delay Discounting ◽

Reference Point ◽

Reference Points ◽

Cognitive Reflection Test ◽

Process Information ◽

Time Discounting ◽

Cognitive Reflection ◽

The Way

Abstract. In this work, we investigated individual differences in cognitive reflection effects on delay discounting – a preference for smaller sooner over larger later payoff. People are claimed to prefer more these alternatives they considered first – so-called reference point – over the alternatives they considered later. Cognitive reflection affects the way individuals process information, with less reflective individuals relying predominantly on the first information they consider, thus, being more susceptible to reference points as compared to more reflective individuals. In Experiment 1, we confirmed that individuals who scored high on the Cognitive Reflection Test discount less strongly than less reflective individuals, but we also show that such individuals are less susceptible to imposed reference points. Experiment 2 replicated these findings additionally providing evidence that cognitive reflection predicts discounting strength and (in)dependency to reference points over and above individual difference in numeracy.

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Fishing catch shares in the face of global change: a framework for integrating cumulative impacts and single species management

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f10-118 ◽

2010 ◽

Vol 67 (12) ◽

pp. 1968-1982 ◽

Cited By ~ 57

Author(s):

Isaac C. Kaplan ◽

Phillip S. Levin ◽

Merrick Burden ◽

Elizabeth A. Fulton

Keyword(s):

Global Change ◽

Ocean Acidification ◽

Fishery Management ◽

Single Species ◽

Ecosystem Model ◽

Careful Consideration ◽

Reference Points ◽

Cumulative Impacts ◽

English Sole ◽

Modeling Tools

Any fishery management scheme, such as individual fishing quotas (IFQs) or marine protected areas, should be designed to be robust to potential shifts in the biophysical system. Here we couple possible catch scenarios under an IFQ scheme with ocean acidification impacts on shelled benthos and plankton, using an Atlantis ecosystem model for the US West Coast. IFQ harvest scenarios alone, in most cases, did not have strong impacts on the food web, beyond the direct effects on harvested species. However, when we added the impacts of ocean acidification, the abundance of commercially important groundfish such as English sole ( Pleuronectes vetulus ), arrowtooth flounder ( Atheresthes stomias ), and yellowtail rockfish ( Sebastes flavidus ) declined up to 20%–80%, owing to the loss of shelled prey items from their diet. English sole exhibited a 10-fold decline in potential catch and economic yield when confronted with strong acidification impacts on shelled benthos. Therefore, it seems prudent to complement IFQs with careful consideration of potential global change effects such as acidification. Our analysis provides an example of how new ecosystem modeling tools that evaluate cumulative impacts can be integrated with established management reference points and decision mechanisms.

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