Translating ecosystem indicators into decision criteria

Abstract Defining and attaining suitable management goals probably represent the most difficult part of ecosystem-based fisheries management. To achieve those goals we ultimately need to define ecosystem overfishing in a way that is analogous to the concept used in single-species management. Ecosystem-based control rules can then be formulated when various ecosystem indicators are evaluated with respect to fishing-induced changes. However, these multi-attribute control rules will be less straightforward than those applied typically in single-species management, and may represent a gradient rather than binary decision criteria. Some ecosystem-based decision criteria are suggested, based on indicators empirically derived from the Georges Bank, Gulf of Maine ecosystem. Further development in the translation of ecosystem indicators into decision criteria is one of the major areas for progress in fisheries science and management.

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Size matters: How single-species management can contribute to ecosystem-based fisheries management

Fisheries Research ◽

10.1016/j.fishres.2008.01.005 ◽

2008 ◽

Vol 92 (2-3) ◽

pp. 231-241 ◽

Cited By ~ 105

Author(s):

Rainer Froese ◽

Amanda Stern-Pirlot ◽

Henning Winker ◽

Didier Gascuel

Keyword(s):

Fisheries Management ◽

Single Species ◽

Species Management ◽

Ecosystem Based Fisheries Management

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Atlantic puffin diet reflects haddock and redfish abundance in the Gulf of Maine

Marine Ecology Progress Series ◽

10.3354/meps13537 ◽

2020 ◽

Vol 656 ◽

pp. 75-87

Author(s):

KM Depot ◽

LC Scopel ◽

SW Kress ◽

P Shannon ◽

AW Diamond ◽

...

Keyword(s):

Fisheries Management ◽

Large Scale ◽

Gulf Of Maine ◽

Strong Predictor ◽

Principal Component ◽

Melanogrammus Aeglefinus ◽

Generalist Predator ◽

Successful Implementation ◽

Ecosystem Based Fisheries Management ◽

Atlantic Puffin

Ecosystem-based fisheries management, which considers the interactions between fisheries, target species, and the physical and biological components of ecosystems, is necessary to ensure that directed fisheries avoid adverse impacts to ecosystems over the long term. The successful implementation of ecosystem-based fisheries management requires an understanding of predator-prey relationships and ways to operationalize such relationships to inform fisheries management. Here, we investigated if the diet of a generalist predator, Atlantic puffin Fratercula arctica, can be used as an indicator of the abundance of 2 commercially exploited prey species (haddock Melanogrammus aeglefinus and Acadian redfish Sebastes fasciatus) in the Gulf of Maine. Because haddock and redfish eaten by puffins are juveniles (age 0), there is potential to use their proportions and lengths in puffin diet to better understand the processes influencing haddock and redfish recruitment. By using principal component analysis to develop measures of diet across multiple puffin colonies, we show both spatial variation and large-scale patterns in the proportions and lengths of haddock and redfish in puffin diet. Spawning stock biomass was a strong predictor of haddock proportion in puffin diet and a moderate predictor of redfish proportion; however, proportions in puffin diet did not predict age-1 recruitment, suggesting that variation in recruitment is caused by processes that occur after the puffin breeding season and which affect the survival of older juveniles. Haddock length on one colony was a moderate predictor of age-1 recruitment. We conclude that puffin diet can be used as an indicator of haddock and redfish abundance.

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Marine ecosystem assessment in a fisheries management context

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f02-115 ◽

2002 ◽

Vol 59 (9) ◽

pp. 1429-1440 ◽

Cited By ~ 145

Author(s):

Jason S Link ◽

Jon K.T Brodziak ◽

Steve F Edwards ◽

William J Overholtz ◽

David Mountain ◽

...

Keyword(s):

Fisheries Management ◽

Marine Ecosystem ◽

Single Species ◽

Reference Points ◽

System Level ◽

Multivariate Statistical Methods ◽

Multivariate Statistical ◽

Management Context ◽

Ecosystem Level ◽

Ecosystem Based Fisheries Management

We examined a suite of abiotic, biotic, and human metrics for the northeast U.S. continental shelf ecosystem at the aggregate, community, and system level (>30 different metrics) over three decades. Our primary goals were to describe ecosystem status, to improve understanding of the relationships between key ecosystem processes, and to evaluate potential reference points for ecosystem-based fisheries management (EBFM). To this end, empirical indicators of ecosystem status were examined and standard multivariate statistical methods were applied to describe changes in the system. We found that (i) a suite of metrics is required to accurately characterize ecosystem status and, conversely, that focusing on a few metrics may be misleading; (ii) assessment of ecosystem status is feasible for marine ecosystems; (iii) multivariate points of reference can be determined for EBFM; and (iv) the concept of reference directions could provide an ecosystem level analog to single-species reference points.

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Time-series metabarcoding analysis of zooplankton diversity of the NW Atlantic continental shelf

ICES Journal of Marine Science ◽

10.1093/icesjms/fsz021 ◽

2019 ◽

Vol 76 (4) ◽

pp. 1162-1176 ◽

Cited By ~ 7

Author(s):

Ann Bucklin ◽

Heidi D Yeh ◽

Jennifer M Questel ◽

David E Richardson ◽

Bo Reese ◽

...

Keyword(s):

Time Series ◽

Gulf Of Maine ◽

Diversity Index ◽

Hypervariable Region ◽

Detailed Examination ◽

Science Center ◽

Ecosystem Monitoring ◽

Fisheries Science ◽

Ocean Ecosystem ◽

Taxonomic Groups

Abstract Biodiversity of zooplankton is central to the functioning of ocean ecosystems, yet morphological taxonomic analysis requires teams of experts and detailed examination of many samples. Metabarcoding (DNA sequencing of short amplified regions of one or a few genes from environmental samples) is a powerful tool for analysis of the composition and diversity of natural communities. The 18S rRNA V9 hypervariable region was sequenced for 26 zooplankton samples collected from the Gulf of Maine, Georges Bank, and Mid-Atlantic Bight during ecosystem monitoring surveys by the U.S. Northeast Fisheries Science Center during 2002–2012. A total of 7 648 033 sequences and 22 072 operational taxonomic units (OTUs) were identified and classified into 28 taxonomic groups of plankton. Comparative analysis of molecular (V9 sequence numbers) and morphological (abundance counts) focused on seven taxonomic groups and revealed similar patterns of variation among years and regions. Sequence numbers and abundance counts showed positive correlation for all groups, with significant correlations (p < 0.05) for Calanoida, Gastropoda, and Chaetognatha. Shannon diversity index values calculated using sequence numbers and abundance counts showed highly significant correlation (r = 0.625; p < 0.001) across all regions during 2002–2012. This study demonstrates the potential of metabarcoding for time-series analysis of zooplankton biodiversity, ocean ecosystem assessment, and fisheries management.

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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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The effect of sea surface temperature on the structure and connectivity of species landings interaction networks in a multispecies recreational fishery.

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2021-0085 ◽

2022 ◽

Author(s):

Kayla Mackenzie Blincow ◽

Brice X Semmens

Keyword(s):

Time Series ◽

Dynamic Modelling ◽

Single Species ◽

Unintended Consequences ◽

Interaction Networks ◽

Multispecies Fisheries ◽

Recreational Fishery ◽

Species Management ◽

Management Approaches ◽

Modelling Methods

Multispecies fisheries, particularly those that routinely adapt the timing, location, and methods of fishing to prioritize fishery targets, present a challenge to traditional single-species management approaches. Efforts to develop robust management for multispecies fisheries require an understanding of how priorities drive the network of interactions between catch of different species, especially given the added challenges presented by climate change. Using 35 years of landings data from a southern California recreational fishery, we leveraged empirical dynamic modelling methods to construct causal interaction networks among the main species targeted by the fishery. We found strong evidence for dependencies among species landings time series driven by apparent hierarchical catch preference within the fishery. In addition, by parsing the landings time series into anomalously cool, normal, and anomalously warm regimes (the last reflecting ocean temperatures anticipated by 2040), we found that network complexity was highest during warm periods. Our findings suggest that as ocean temperatures continue to rise, so too will the risk of unintended consequences from single species management in this multispecies fishery.

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Seabird diets as bioindicators of Atlantic herring recruitment and stock size: a new tool for ecosystem-based fisheries management

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2017-0140 ◽

2018 ◽

Vol 75 (8) ◽

pp. 1215-1229 ◽

Cited By ~ 3

Author(s):

Lauren C. Scopel ◽

Antony W. Diamond ◽

Stephen W. Kress ◽

Adrian R. Hards ◽

Paula Shannon

Keyword(s):

Fishery Management ◽

Gulf Of Maine ◽

Clupea Harengus ◽

Data Series ◽

Atlantic Herring ◽

Stock Biomass ◽

Stock Assessments ◽

Spawning Stock ◽

Fishery Data ◽

Ecosystem Based Fisheries Management

Ecosystem-based fishery management requires understanding of relationships between exploited fish and their predators, such as seabirds. We used exploratory regression analyses to model relationships between Atlantic herring (Clupea harengus) in the diet of seabird chicks at nine nesting colonies in the Gulf of Maine and four types of fishery- and survey-derived herring data. We found several strong relationships, which suggests spatial structuring in herring stocks and likely patterns of herring movements before they recruit into the fishery. Some types of herring data seldom used in stock assessments — notably acoustic surveys, fixed-gear landings, and mass-at-age (i.e., weight-at-age) — correlated as strongly with seabird data as more commonly used series, such as mobile-gear landings and modeled spawning stock biomass. Seabird chick diets collected at specific locations thus offer a promising means to assess the size, distribution, and abundance of juvenile herring across a broad area prior to recruitment, which is a major source of uncertainty in fisheries. Common terns (Sterna hirundo) showed the most potential as a bioindicator, correlating well and showing consistent spatial patterns with 11 of 13 fishery data series.

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A length-based multispecies model for evaluating community responses to fishing

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f06-039 ◽

2006 ◽

Vol 63 (6) ◽

pp. 1344-1359 ◽

Cited By ~ 100

Author(s):

Stephen J Hall ◽

Jeremy S Collie ◽

Daniel E Duplisea ◽

Simon Jennings ◽

Mark Bravington ◽

...

Keyword(s):

Fish Species ◽

Single Species ◽

Community Level ◽

Fishing Mortality ◽

Stock Biomass ◽

Spawning Stock ◽

Multispecies Model ◽

Species Declines ◽

Ecosystem Based Fisheries Management ◽

Biomass Spectra

Quantitative ecosystem indicators are needed to fulfill the mandate for ecosystem-based fisheries management. A variety of community metrics could potentially be used, but before reference levels for such indices can be established the sensitivity of candidate indices to fishing and other disturbances must be determined. One approach for obtaining such information is to test candidate indicators with models that mimic real ecosystems and can be manipulated experimentally. Here we construct a size-based multispecies model of a community of fish species that interact by predation. The model was parameterized for 21 fish species to obtain a predation-regulated community. Following an analysis of the sensitivity of the model to parameter uncertainty, we tested the sensitivity of community-level indicators to increasing levels of fishing mortality (F). Abundance and biomass spectra were sensitive to fishing mortality, with the slope decreasing with increasing F. Species diversity size spectra were also very sensitive to F, with diversity in the largest size classes declining rapidly. In contrast, k-dominance curves were less sensitive to fishing pressure. Importantly, however, although most community-level metrics showed clear trends in response to fishing, single-species declines in spawning stock biomass were the most sensitive indicators of fishing effects.

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