Estimating steepness of the stock-recruitment relationship in Chilean fish stocks using meta-analysis

Abstract The accessibility of databases of global or regional stock assessment outputs is leading to an increase in meta-analysis of the dynamics of fish stocks. In most of these analyses, each of the time-series is generally assumed to be directly comparable. However, the approach to stock assessment employed, and the associated modelling assumptions, can have an important influence on the characteristics of each time-series. We explore this idea by investigating recruitment time-series with three different recruitment parameterizations: a stock–recruitment model, a random-walk time-series model, and non-parametric “free” estimation of recruitment. We show that the recruitment time-series is sensitive to model assumptions and this can impact reference points in management, the perception of variability in recruitment and thus undermine meta-analyses. The assumption of the direct comparability of recruitment time-series in databases is therefore not consistent across or within species and stocks. Caution is therefore required as perhaps the characteristics of the time-series of stock dynamics may be determined by the model used to generate them, rather than underlying ecological phenomena. This is especially true when information about cohort abundance is noisy or lacking.

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Towards a new recruitment paradigm for fish stocks

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f96-272 ◽

1997 ◽

Vol 54 (4) ◽

pp. 969-977 ◽

Cited By ~ 61

Author(s):

D J Gilbert

Keyword(s):

Time Series ◽

Null Hypothesis ◽

Meta Analysis ◽

Fish Stock ◽

Test Statistic ◽

Mean Values ◽

Fish Stocks ◽

Independent Events ◽

Alternative Hypotheses ◽

Stock Recruitment

The stock recruitment paradigm involves the hypothesis that recruitment (R) to a fish stock is positively related to the spawning stock biomass (SSB) of the stock, at low SSB. I propose a ``recruitment states'' hypothesis wherein R is independent of SSB but has different mean values during successive periods. Meta-analysis was used to test the null hypothesis that recruitment is a series of random, independent events, against these two alternative hypotheses, for 153 marine spawning bony fish stocks and 31 salmonid stocks. A test statistic for the stock recruitment paradigm, based on estimating derivatives from the first differences of the time series, was not significant for the marine stocks. The null hypothesis was rejected for the salmonid stocks. Recruitment states models significantly fitted time series for the marine stocks. Ricker models also significantly fitted these data, conflicting with the derivatives test result. However, because SSB is dependent on R, lagged by the age at maturity, a period in a low recruitment state would tend to lead to a period of low SSB. Therefore, the significance of the fit to the Ricker model may have been spurious. The recruitment states model best explained the meta-dataset for the marine stocks.

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Depensation in fish stocks: a hierarchic Bayesian meta-analysis

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f97-105 ◽

1997 ◽

Vol 54 (9) ◽

pp. 1976-1984 ◽

Cited By ~ 119

Author(s):

M Liermann ◽

R Hilborn

Keyword(s):

Probability Distribution ◽

Hierarchical Modeling ◽

Meta Analysis ◽

Data Set ◽

Fish Stocks ◽

Stock Recruitment ◽

Taxonomic Groups ◽

Bayesian Prior ◽

Different Levels

The probability of different levels of depensation within four taxonomic groups was calculated using a Bayesian technique called hierarchical modeling. With this method we combined spawner-recruit data from many stocks within a taxon to estimate the distribution describing the variability of depensation within that taxon. The spawner-recruit model we use allows for both depensation (lower than expected recruits at low population levels) and hypercompensation (where recruits are higher than expected at low population levels). The end product of our analysis is a probability distribution that can be used as a Bayesian prior when analyzing a new data set. We examined four taxonomic groups (the salmonids, gadiforms, clupeiforms and pleuronectiforms) and found that, for all of the taxa, the most likely values fell close to or within the range of no depensation. However, because the distributions were very broad we suggest that analysis of stock recruitment data should incorporate spawner-recruit curves that include the possibility of depensation and hypercompensation.

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Indicators of AEI Applied to the Delaware Estuary

The Scientific World JOURNAL ◽

10.1100/tsw.2002.346 ◽

2002 ◽

Vol 2 ◽

pp. 169-189 ◽

Cited By ~ 3

Author(s):

Lawrence W. Barnthouse ◽

Douglas G. Heimbuch ◽

Vaughn C. Anthony ◽

Ray W. Hilborn ◽

Ransom A. Myers

Keyword(s):

Meta Analysis ◽

Juvenile Fish ◽

Fish Populations ◽

Weight Of Evidence ◽

Data Sets ◽

Delaware Estuary ◽

Fish Stocks ◽

Trends Analysis ◽

Definition Of

We evaluated the impacts of entrainment and impingement at the Salem Generating Station on fish populations and communities in the Delaware Estuary. In the absence of an agreed-upon regulatory definition of “adverse environmental impact” (AEI), we developed three independent benchmarks of AEI based on observed or predicted changes that could threaten the sustainability of a population or the integrity of a community.Our benchmarks of AEI included: (1) disruption of the balanced indigenous community of fish in the vicinity of Salem (the “BIC” analysis); (2) a continued downward trend in the abundance of one or more susceptible fish species (the “Trends” analysis); and (3) occurrence of entrainment/impingement mortality sufficient, in combination with fishing mortality, to jeopardize the future sustainability of one or more populations (the “Stock Jeopardy” analysis).The BIC analysis utilized nearly 30 years of species presence/absence data collected in the immediate vicinity of Salem. The Trends analysis examined three independent data sets that document trends in the abundance of juvenile fish throughout the estuary over the past 20 years. The Stock Jeopardy analysis used two different assessment models to quantify potential long-term impacts of entrainment and impingement on susceptible fish populations. For one of these models, the compensatory capacities of the modeled species were quantified through meta-analysis of spawner-recruit data available for several hundred fish stocks.All three analyses indicated that the fish populations and communities of the Delaware Estuary are healthy and show no evidence of an adverse impact due to Salem. Although the specific models and analyses used at Salem are not applicable to every facility, we believe that a weight of evidence approach that evaluates multiple benchmarks of AEI using both retrospective and predictive methods is the best approach for assessing entrainment and impingement impacts at existing facilities.

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Population variability under stressors is dependent on body mass growth and asymptotic body size

Royal Society Open Science ◽

10.1098/rsos.192011 ◽

2020 ◽

Vol 7 (2) ◽

pp. 192011

Author(s):

Leonie Färber ◽

Rob van Gemert ◽

Øystein Langangen ◽

Joël M. Durant ◽

Ken H. Andersen

Keyword(s):

Body Mass ◽

Life Histories ◽

Random Noise ◽

Fish Stock ◽

Vital Rates ◽

Anthropogenic Pressures ◽

Fish Stocks ◽

Asymptotic Size ◽

Wide Range ◽

Stock Recruitment

The recruitment and biomass of a fish stock are influenced by their environmental conditions and anthropogenic pressures such as fishing. The variability in the environment often translates into fluctuations in recruitment, which then propagate throughout the stock biomass. In order to manage fish stocks sustainably, it is necessary to understand their dynamics. Here, we systematically explore the dynamics and sensitivity of fish stock recruitment and biomass to environmental noise. Using an age-structured and trait-based model, we explore random noise (white noise) and autocorrelated noise (red noise) in combination with low to high levels of harvesting. We determine the vital rates of stocks covering a wide range of possible body mass (size) growth rates and asymptotic size parameter combinations. Our study indicates that the variability of stock recruitment and biomass are probably correlated with the stock's asymptotic size and growth rate. We find that fast-growing and large-sized fish stocks are likely to be less vulnerable to disturbances than slow-growing and small-sized fish stocks. We show how the natural variability in fish stocks is amplified by fishing, not just for one stock but for a broad range of fish life histories.

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Age-structure-dependent recruitment: a meta-analysis applied to Northeast Atlantic fish stocks

ICES Journal of Marine Science ◽

10.1093/icesjms/fsq032 ◽

2010 ◽

Vol 67 (9) ◽

pp. 1921-1930 ◽

Cited By ~ 46

Author(s):

Thomas Brunel

Keyword(s):

Opposite Direction ◽

Age Structure ◽

Environmental Variability ◽

Meta Analysis ◽

Stock Level ◽

Fish Stocks ◽

Biological Basis ◽

Northeast Atlantic ◽

Age Diversity ◽

Meta Analyses

Abstract Brunel, T. 2010. Age-structure-dependent recruitment: a meta-analysis applied to Northeast Atlantic fish stocks. – ICES Journal of Marine Science, 67: 1921–1930. Exploitation alters the age structure of fish stocks. Several stock-specific studies have suggested that changes in the age structure might have consequences for subsequent recruitment, but the evidence is not universal. To investigate how common such effects are among 39 Northeast Atlantic fish stocks, relationships were tested between age structure (spawner mean age, age diversity, and proportion of recruit spawners) and recruitment (number of recruits, sensitivity to environment, and recruitment variability). Significant correlations in the expected direction were observed for a few stocks, but not for the majority; significant correlations in the opposite direction were also found. Meta-analyses combining the stock-level tests revealed that none of the effects were significant overall. However, effects were significant for some species (cod, haddock, and plaice) and indices. The low variability in the age structure might explain the absence of significant effects for individual stocks. Other reasons could be the absence of a biological basis (reproductive characteristics not dependent on age) or the stronger influence of environmental variability than of age structure on recruitment.

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Optimal F0.1 Criteria and Their Relationship to Maximum Sustainable Yield

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f87-335 ◽

1987 ◽

Vol 44 (S2) ◽

pp. s339-s348 ◽

Cited By ~ 56

Author(s):

R. B. Deriso

Keyword(s):

Quantitative Relationship ◽

Maximum Sustainable Yield ◽

Sustainable Yield ◽

Fish Stocks ◽

Pacific Halibut ◽

Western Lake ◽

Gadus Macrocephalus ◽

Hippoglossus Stenolepis ◽

Stock Recruitment ◽

Yield Per Recruit

There is a unique size of entry into the fishable population that maximizes yield per recruit when an F0.1 fishing criterion is applied to the simple theory of fishing developed by Beverton and Holt in 1957. I define such a pair of parameters (size of entry, F0.1 value) to be the optimal F0.1 criteria and show that they are characterized by the single quantity M/K. A quantitative relationship is established between maximum sustainable yield and the optimal F0.1 criteria for a model population where recruitment is governed by a Ricker stock–recruitment function. This new theory is applied to three fish stocks: Pacific halibut (Hippoglossus stenolepis), western Lake Erie walleye (Stizostedion vitreum vitreum), and Bering Sea Pacific cod (Gadus macrocephalus).

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Estimating cross-population variation in juvenile compensation in survival for bull trout (Salvelinus confluentus): a Bayesian hierarchical approach

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2017-0555 ◽

2019 ◽

Vol 76 (9) ◽

pp. 1571-1580 ◽

Cited By ~ 1

Author(s):

Rachel Chudnow ◽

Brett van Poorten ◽

Murdoch McAllister

Keyword(s):

Meta Analysis ◽

Fish Population ◽

Population Variation ◽

Bull Trout ◽

Salvelinus Confluentus ◽

Bayesian Hierarchical ◽

Compensation Ratio ◽

Recreational Angling ◽

Stock Recruitment ◽

High Uncertainty

Juvenile compensation in survival, quantified as compensation ratio (CR), is critical for fish population persistence. At present, no estimate of this key parameter exists for bull trout (Salvelinus confluentus). This species has a conservation listing and is targeted by recreational angling in portions of its range. Obtaining accurate estimates of CR is crucial to aid recovery efforts and develop sustainable fisheries policies. This investigation develops a hierarchical Bayesian meta-analysis to estimate CR and explore the functional form of stock–recruitment for bull trout. Results show bull trout have high scope for density-dependent compensation evidenced by CR estimates generated herein and by previous research. This demonstrates changes in habitat quality and quantity are likely limiting recovery of many populations. However, owing to lack of data, variance is high. Limitations in available data for this analysis are due to the high cost and operational difficulty of sampling, and high uncertainty in CR estimates. This study highlights the importance of collecting additional paired stock–recruitment data to facilitate future investigations and reduce variance in CR estimates for bull trout.

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Parasites as biological tags of fish stocks: a meta-analysis of their discriminatory power

Parasitology ◽

10.1017/s0031182013001534 ◽

2013 ◽

Vol 142 (1) ◽

pp. 145-155 ◽

Cited By ~ 21

Author(s):

ROBERT POULIN ◽

TSUKUSHI KAMIYA

Keyword(s):

Marine Fish ◽

Meta Analysis ◽

Discriminatory Power ◽

Correct Classification ◽

Fish Stocks ◽

Clear Cut ◽

Stock Discrimination ◽

High Discriminatory Power ◽

Discriminant Analyses ◽

Biological Tags

SUMMARYThe use of parasites as biological tags to discriminate among marine fish stocks has become a widely accepted method in fisheries management. Here, we first link this approach to its unstated ecological foundation, the decay in the similarity of the species composition of assemblages as a function of increasing distance between them, a phenomenon almost universal in nature. We explain how distance decay of similarity can influence the use of parasites as biological tags. Then, we perform a meta-analysis of 61 uses of parasites as tags of marine fish populations in multivariate discriminant analyses, obtained from 29 articles. Our main finding is that across all studies, the observed overall probability of correct classification of fish based on parasite data was about 71%. This corresponds to a two-fold improvement over the rate of correct classification expected by chance alone, and the average effect size (Zr = 0·463) computed from the original values was also indicative of a medium-to-large effect. However, none of the moderator variables included in the meta-analysis had a significant effect on the proportion of correct classification; these moderators included the total number of fish sampled, the number of parasite species used in the discriminant analysis, the number of localities from which fish were sampled, the minimum and maximum distance between any pair of sampling localities, etc. Therefore, there are no clear-cut situations in which the use of parasites as tags is more useful than others. Finally, we provide recommendations for the future usage of parasites as tags for stock discrimination, to ensure that future applications of the method achieve statistical rigour and a high discriminatory power.

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Changing recruitment capacity in global fish stocks

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1504709112 ◽

2015 ◽

Vol 113 (1) ◽

pp. 134-139 ◽

Cited By ~ 71

Author(s):

Gregory L. Britten ◽

Michael Dowd ◽

Boris Worm

Keyword(s):

Environmental Changes ◽

Meta Analysis ◽

Chlorophyll Concentration ◽

Fish Stock ◽

Productive Capacity ◽

Large Variability ◽

Fish Stocks ◽

Large Marine Ecosystems ◽

The North ◽

Spawning Stock

Marine fish and invertebrates are shifting their regional and global distributions in response to climate change, but it is unclear whether their productivity is being affected as well. Here we tested for time-varying trends in biological productivity parameters across 262 fish stocks of 127 species in 39 large marine ecosystems and high-seas areas (hereafter LMEs). This global meta-analysis revealed widespread changes in the relationship between spawning stock size and the production of juvenile offspring (recruitment), suggesting fundamental biological change in fish stock productivity at early life stages. Across regions, we estimate that average recruitment capacity has declined at a rate approximately equal to 3% of the historical maximum per decade. However, we observed large variability among stocks and regions; for example, highly negative trends in the North Atlantic contrast with more neutral patterns in the North Pacific. The extent of biological change in each LME was significantly related to observed changes in phytoplankton chlorophyll concentration and the intensity of historical overfishing in that ecosystem. We conclude that both environmental changes and chronic overfishing have already affected the productive capacity of many stocks at the recruitment stage of the life cycle. These results provide a baseline for ecosystem-based fisheries management and may help adjust expectations for future food production from the oceans.

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