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Jeanjean M, Goix S, Dron J, Periot M, Austruy A, Douib K, Persoons R, Etienne MP, Revenko G, Chamaret P. Influence of environmental and dietary exposures on metals accumulation among the residents of a major industrial harbour (Fos-sur-Mer, France). J Trace Elem Med Biol 2022; 73:127021. [PMID: 35753173 DOI: 10.1016/j.jtemb.2022.127021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 06/10/2022] [Accepted: 06/16/2022] [Indexed: 10/18/2022]
Abstract
OBJECTIVES We sought to determine whether the residents living closer to the core industrial zone (Fos-sur-Mer) had higher trace metals blood and urinary levels than residents who lived further away (Saint-Martin-de-Crau). MATERIALS AND METHODS As part of The INDEX study, we measured the following trace metals into blood and urine samples of 138 participants (80 in the core industrial zone and 58 in the reference area): Antimony, Arsenic, Cadmium, Chromium, Cobalt, Mercury, Nickel, Lead and Vanadium. Participants were recruited using a stratified random sampling method and had to meet the following inclusion criteria: 30-65 years old, living in the area since at least 3 years, not working in the industrial sector, non-smoker. We used single-pollutant multivariate linear regression models, using substitution when censored data were under 15 % and Tobit models alternatively, adjusting for personal physiological, social, dietary, housing characteristics and leisure activities. We also measured these trace metals in samples of lichens (Xanthoria parietina) and atmospheric particles (PM2.5). RESULTS We showed higher lichen and air levels of several metals (Cd, Cr, Co, Ni and Pb) in the exposed area. Living close to the core industrial zone was significantly associated with an increase in blood levels of lead (adjusted geometric mean = 17.2 [15.8-18.7] vs 15.1 [13.7-16.7] µg.L-1, p < 0.05). We report significant increase of some metals urinary levels among residents of the industrial port zone, as the result of the use of the environment, itself contaminated by industrial activities: dietary history of self-consumption of vegetables (Cadmium), eggs and poultries (Vanadium). However, Vanadium levels were greater among self-consumers of poultry in the reference area and gardeners had circulatory levels of Lead greater than non-gardeners only in the reference area. Consumption of non-local sea-products increased the level of Cadmium. CONCLUSIONS These results brought interesting clues, in complement to national programs, regarding the exposure to trace metals of residents living in a major industrial harbor.
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Affiliation(s)
- Maxime Jeanjean
- Institut Ecocitoyen pour la Connaissance des Pollutions - Centre de Vie La Fossette, RD 268, 13270 Fos-sur-Mer, France.
| | - Sylvaine Goix
- Institut Ecocitoyen pour la Connaissance des Pollutions - Centre de Vie La Fossette, RD 268, 13270 Fos-sur-Mer, France
| | - Julien Dron
- Institut Ecocitoyen pour la Connaissance des Pollutions - Centre de Vie La Fossette, RD 268, 13270 Fos-sur-Mer, France
| | - Marine Periot
- Institut Ecocitoyen pour la Connaissance des Pollutions - Centre de Vie La Fossette, RD 268, 13270 Fos-sur-Mer, France
| | - Annabelle Austruy
- Institut Ecocitoyen pour la Connaissance des Pollutions - Centre de Vie La Fossette, RD 268, 13270 Fos-sur-Mer, France
| | - Khaled Douib
- Institut Ecocitoyen pour la Connaissance des Pollutions - Centre de Vie La Fossette, RD 268, 13270 Fos-sur-Mer, France
| | - Renaud Persoons
- University of Grenoble Alpes, CNRS, Grenoble INP, CHU Grenoble Alpes, TIMC, 38000 Grenoble, France
| | - Marie-Pierre Etienne
- University of Rennes, Agrocampus Ouest, CNRS, UMR 6625 IRMAR, F-35000 Rennes, France
| | - Gautier Revenko
- Institut Ecocitoyen pour la Connaissance des Pollutions - Centre de Vie La Fossette, RD 268, 13270 Fos-sur-Mer, France
| | - Philippe Chamaret
- Institut Ecocitoyen pour la Connaissance des Pollutions - Centre de Vie La Fossette, RD 268, 13270 Fos-sur-Mer, France
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Genitoni J, Vassaux D, Delaunay A, Citerne S, Portillo Lemus L, Etienne MP, Renault D, Stoeckel S, Barloy D, Maury S. Hypomethylation of the aquatic invasive plant, Ludwigia grandiflora subsp. hexapetala mimics the adaptive transition into the terrestrial morphotype. Physiol Plant 2020; 170:280-298. [PMID: 32623739 DOI: 10.1111/ppl.13162] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 06/17/2020] [Accepted: 06/29/2020] [Indexed: 06/11/2023]
Abstract
Ongoing global changes affect ecosystems and open up new opportunities for biological invasion. The ability of invasive species to rapidly adapt to new environments represents a relevant model for studying short-term adaptation mechanisms. The aquatic invasive plant, Ludwigia grandiflora subsp. hexapetala, is classified as harmful in European rivers. In French wet meadows, this species has shown a rapid transition from aquatic to terrestrial environments with emergence of two distinct morphotypes in 5 years. To understand the heritable mechanisms involved in adjustment to such a new environment, we investigate both genetic and epigenetic as possible sources of flexibility involved in this fast terrestrial transition. We found a low overall genetic differentiation between the two morphotypes arguing against the possibility that terrestrial morphotype emerged from a new adaptive genetic capacity. Artificial hypomethylation was induced on both morphotypes to assess the epigenetic hypothesis. We analyzed global DNA methylation, morphological changes, phytohormones and metabolite profiles of both morphotype responses in both aquatic and terrestrial conditions in shoot and root tissues. Hypomethylation significantly affected morphological variables, phytohormone levels and the amount of some metabolites. The effects of hypomethylation depended on morphotypes, conditions and plant tissues, which highlighted differences among the morphotypes and their plasticity. Using a correlative integrative approach, we showed that hypomethylation of the aquatic morphotype mimicked the characteristics of the terrestrial morphotype. Our data suggest that DNA methylation rather than a new adaptive genetic capacity is playing a key role in L. grandiflora subsp. hexapetala plasticity during its rapid aquatic to terrestrial transition.
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Affiliation(s)
- Julien Genitoni
- ESE, Ecology and Ecosystem Health, Institut Agro, INRAE, Rennes, 35042, France
- Laboratoire de Biologie des Ligneux et des Grandes Cultures (LBLGC), EA1207 USC1328 INRA, Université d'Orléans, Orléans, 45067, France
| | - Danièle Vassaux
- ESE, Ecology and Ecosystem Health, Institut Agro, INRAE, Rennes, 35042, France
| | - Alain Delaunay
- Laboratoire de Biologie des Ligneux et des Grandes Cultures (LBLGC), EA1207 USC1328 INRA, Université d'Orléans, Orléans, 45067, France
| | - Sylvie Citerne
- Institut Jean-Pierre Bourgin, INRAE, AgroParisTech, Université Paris-Saclay, Versailles, 78000, France
| | - Luis Portillo Lemus
- ESE, Ecology and Ecosystem Health, Institut Agro, INRAE, Rennes, 35042, France
| | - Marie-Pierre Etienne
- Institut Agro, CNRS, Université Rennes, IRMAR (Institut de Recherche Mathématique de Rennes) - UMR 6625, Rennes, F-35000, France
| | - David Renault
- UMR CNRS 6553 EcoBio, University of Rennes 1, Rennes, France
- Institut Universitaire de France, 1 rue Descartes, Paris, France
| | - Solenn Stoeckel
- IGEPP, INRAE, Institut Agro, Université Rennes, Le Rheu, 35653, France
| | - Dominique Barloy
- ESE, Ecology and Ecosystem Health, Institut Agro, INRAE, Rennes, 35042, France
| | - Stéphane Maury
- Laboratoire de Biologie des Ligneux et des Grandes Cultures (LBLGC), EA1207 USC1328 INRA, Université d'Orléans, Orléans, 45067, France
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Tysklind N, Etienne MP, Scotti-Saintagne C, Tinaut A, Casalis M, Troispoux V, Cazal SO, Brousseau L, Ferry B, Scotti I. Microgeographic local adaptation and ecotype distributions: The role of selective processes on early life-history traits in sympatric, ecologically divergent Symphonia populations. Ecol Evol 2020; 10:10735-10753. [PMID: 33072293 PMCID: PMC7548183 DOI: 10.1002/ece3.6731] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 07/29/2020] [Accepted: 08/01/2020] [Indexed: 11/11/2022] Open
Abstract
Trees are characterized by the large number of seeds they produce. Although most of those seeds will never germinate, plenty will. Of those which germinate, many die young, and eventually, only a minute fraction will grow to adult stage and reproduce. Is this just a random process? Do variations in germination and survival at very young stages rely on variations in adaptations to microgeographic heterogeneity? and do these processes matter at all in determining tree species distribution and abundance? We have studied these questions with the Neotropical Symphonia tree species. In the Guiana shield, Symphonia are represented by at least two sympatric taxa or ecotypes, Symphonia globulifera found almost exclusively in bottomlands, and a yet undescribed more generalist taxon/ecotype, Symphonia sp1. A reciprocal transplantation experiment (510 seeds, 16 conditions) was set up and followed over the course of 6 years to evaluate the survival and performance of individuals from different ecotypes and provenances. Germination, survival, growth, and herbivory showed signs of local adaptation, with some combinations of ecotypes and provenances growing faster and surviving better in their own habitat or provenance region. S. globulifera was strongly penalized when planted outside its home habitat but showed the fastest growth rates when planted in its home habitat, suggesting it is a specialist of a high‐risk high‐gain strategy. Conversely, S. sp1 behaved as a generalist, performing well in a variety of environments. The differential performance of seeds and seedlings in the different habitats matches the known distribution of both ecotypes, indicating that environmental filtering at the very early stages can be a key determinant of tree species distributions, even at the microgeographic level and among very closely related taxa. Furthermore, such differential performance also contributes to explain, in part, the maintenance of the different Symphonia ecotypes living in intimate sympatry despite occasional gene flow.
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Affiliation(s)
- Niklas Tysklind
- INRAE UMR0745 EcoFoG AgroParisTech Cirad CNRS Université des Antilles Université de Guyane Kourou Cedex France
| | | | | | - Alexandra Tinaut
- INRAE UMR0745 EcoFoG AgroParisTech Cirad CNRS Université des Antilles Université de Guyane Kourou Cedex France.,Université de Guyane UMR0745 EcoFoG INRAE AgroParisTech Cirad CNRS Université des Antilles Kourou Cedex France
| | - Maxime Casalis
- INRAE UMR0745 EcoFoG AgroParisTech Cirad CNRS Université des Antilles Université de Guyane Kourou Cedex France.,Université de Guyane UMR0745 EcoFoG INRAE AgroParisTech Cirad CNRS Université des Antilles Kourou Cedex France
| | - Valerie Troispoux
- INRAE UMR0745 EcoFoG AgroParisTech Cirad CNRS Université des Antilles Université de Guyane Kourou Cedex France
| | - Saint-Omer Cazal
- INRAE UMR0745 EcoFoG AgroParisTech Cirad CNRS Université des Antilles Université de Guyane Kourou Cedex France
| | - Louise Brousseau
- INRAE UMR0745 EcoFoG AgroParisTech Cirad CNRS Université des Antilles Université de Guyane Kourou Cedex France.,Present address: UMR AMAP IRD Cirad CNRS INRAE Université Montpellier Montpellier France
| | - Bruno Ferry
- AgroParisTech INRAE UMR SILVA Université de Lorraine Nancy France
| | - Ivan Scotti
- INRAE UR629 Ecologie des Forêts Méditerranéennes (URFM) Avignon France
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Abstract
In movement ecology, the few works that have taken collective behaviour into account are data-driven and rely on simplistic theoretical assumptions, relying in metrics that may or may not be measuring what is intended. In the present paper, we focus on pairwise joint-movement behaviour, where individuals move together during at least a segment of their path. We investigate the adequacy of twelve metrics introduced in previous works for assessing joint movement by analysing their theoretical properties and confronting them with contrasting case scenarios. Two criteria are taken into account for review of those metrics: 1) practical use, and 2) dependence on parameters and underlying assumptions. When analysing the similarities between the metrics as defined, we show how some of them can be expressed using general mathematical forms. In addition, we evaluate the ability of each metric to assess specific aspects of joint-movement behaviour: proximity (closeness in space-time) and coordination (synchrony) in direction and speed. We found that some metrics are better suited to assess proximity and others are more sensitive to coordination. To help readers choose metrics, we elaborate a graphical representation of the metrics in the coordination and proximity space based on our results, and give a few examples of proximity and coordination focus in different movement studies.
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Affiliation(s)
- Rocio Joo
- Department of Wildlife Ecology and Conservation, Fort Lauderdale Research and Education Center, University of Florida, 3205 College Avenue, Davie, Florida, 33314 USA
- IFREMER, Ecologie et Modèles pour l’Halieutique, BP 21105, Nantes Cedex 03, 44311 France
| | | | - Nicolas Bez
- MARBEC, IRD, Ifremer, CNRS, Univ Montpellier, Sète, France
| | - Stéphanie Mahévas
- IFREMER, Ecologie et Modèles pour l’Halieutique, BP 21105, Nantes Cedex 03, 44311 France
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Denis T, Richard-Hansen C, Brunaux O, Etienne MP, Guitet S, Hérault B. Biological traits, rather than environment, shape detection curves of large vertebrates in neotropical rainforests. Ecol Appl 2017; 27:1564-1577. [PMID: 28419598 DOI: 10.1002/eap.1549] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 01/10/2017] [Accepted: 02/17/2017] [Indexed: 06/07/2023]
Abstract
Line transect surveys are widely used in Neotropical rainforests to estimate the population abundance of medium- and large-sized vertebrates. The use of indices such as encounter rate has been criticized because the probability of animal detection may fluctuate due to the heterogeneity of environmental conditions among sites. In addition, the morphological and behavioral characteristics (biological traits) of species affect their detectability. In this study, we compared the extent to which environmental conditions and species' biological traits bias abundance estimates in terra firme rainforests in French Guiana. The selected environmental conditions included both physical conditions and forest structure covariates, while the selected biological traits included the morphological and behavioral characteristics of species. We used the distance sampling method to model the detection probability as an explicit function of environmental conditions and biological traits and implemented a model selection process to determine the relative importance of each group of covariates. Biological traits contributed to the variability of animal detectability more than environmental conditions, which had only a marginal effect. Detectability was best for large animals with uniform or disruptive markings that live in groups in the canopy top. Detectability was worst for small, solitary, terrestrial animals with mottled markings. In the terra firme rainforests that represent ~80% of the Amazonia and Guianas regions, our findings support the use of relative indices such as the encounter rate to compare population abundance between sites in species-specific studies. Even though terra firme rainforests may appear similar between regions of Amazonia and the Guianas, comparability must be ensured, especially in forests disturbed by human activity. The detection probability can be used as an indicator of species' vulnerability to hunting and, thus, to the risk of local extinction. Only a few biological trait covariates are required to correctly estimate the detectability of the majority of medium- and large-sized vertebrates. Thus, a biological trait model could be useful in predicting the detection probabilities of rare, uncommon, or localized species for which few data are available to fit the detection function.
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Affiliation(s)
- Thomas Denis
- ONCFS, UMR EcoFoG, AgroParisTech, Cirad, CNRS, INRA, Université des Antilles, Université de Guyane, 97310, Kourou, French Guiana, France
- Université de Guyane, UMR EcoFoG, AgroParisTech, Cirad, CNRS, INRA, Université des Antilles, 97310, Kourou, French Guiana, France
| | - Cécile Richard-Hansen
- ONCFS, UMR EcoFoG, AgroParisTech, Cirad, CNRS, INRA, Université des Antilles, Université de Guyane, 97310, Kourou, French Guiana, France
| | - Olivier Brunaux
- ONF, R&D, Réserve de Montabo, BP 7002, 97300, Cayenne, French Guiana, France
| | | | - Stéphane Guitet
- ONF, R&D, Réserve de Montabo, BP 7002, 97300, Cayenne, French Guiana, France
- INRA, UMR Amap, TA A51/PS2, 34000, Montpellier, France
| | - Bruno Hérault
- Université de Guyane, UMR EcoFoG, AgroParisTech, Cirad, CNRS, INRA, Université des Antilles, 97310, Kourou, French Guiana, France
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Gimenez O, Buckland ST, Morgan BJT, Bez N, Bertrand S, Choquet R, Dray S, Etienne MP, Fewster R, Gosselin F, Mérigot B, Monestiez P, Morales JM, Mortier F, Munoz F, Ovaskainen O, Pavoine S, Pradel R, Schurr FM, Thomas L, Thuiller W, Trenkel V, de Valpine P, Rexstad E. Statistical ecology comes of age. Biol Lett 2015; 10:20140698. [PMID: 25540151 PMCID: PMC4298184 DOI: 10.1098/rsbl.2014.0698] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The desire to predict the consequences of global environmental change has been the driver towards more realistic models embracing the variability and uncertainties inherent in ecology. Statistical ecology has gelled over the past decade as a discipline that moves away from describing patterns towards modelling the ecological processes that generate these patterns. Following the fourth International Statistical Ecology Conference (1–4 July 2014) in Montpellier, France, we analyse current trends in statistical ecology. Important advances in the analysis of individual movement, and in the modelling of population dynamics and species distributions, are made possible by the increasing use of hierarchical and hidden process models. Exciting research perspectives include the development of methods to interpret citizen science data and of efficient, flexible computational algorithms for model fitting. Statistical ecology has come of age: it now provides a general and mathematically rigorous framework linking ecological theory and empirical data.
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Affiliation(s)
- Olivier Gimenez
- CEFE UMR 5175, CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, 1919 Route de Mende, 34293 Montpellier Cedex 5, France
| | - Stephen T Buckland
- Centre for Research into Ecological and Environmental Modelling, University of St Andrews, St Andrews KY16 9LZ, UK
| | - Byron J T Morgan
- School of Mathematics, Statistics and Actuarial Science, University of Kent, Canterbury, Kent CT2 7NF, UK
| | | | | | - Rémi Choquet
- CEFE UMR 5175, CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, 1919 Route de Mende, 34293 Montpellier Cedex 5, France
| | - Stéphane Dray
- Université de Lyon, F-69000, Lyon; Université Lyon 1; CNRS, UMR5558, Laboratoire de 18 Biométrie et Biologie Evolutive, F-69622, Villeurbanne, France
| | | | - Rachel Fewster
- Department of Statistics, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Frédéric Gosselin
- Irstea, UR EFNO, Centre de Nogent-sur-Vernisson, 45290 Nogent-sur-Vernisson, France
| | | | | | - Juan M Morales
- Laboratorio Ecotono, CRUB, INIBIOMA-CONICET, Bariloche, Argentina
| | | | - François Munoz
- UM2, UMR AMAP, Bd de la Lironde, TA A-51/PS2, 34398 Montpellier Cedex 5, France
| | - Otso Ovaskainen
- Department of Biosciences, University of Helsinki, Helsinki, Finland
| | - Sandrine Pavoine
- UMR 7204 CNRS UPMC, Centre for Ecology and Conservation Sciences, Muséum National d'Histoire Naturelle, 55-61 rue Buffon, 75005 Paris, France Mathematical Ecology Research Group, Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
| | - Roger Pradel
- CEFE UMR 5175, CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, 1919 Route de Mende, 34293 Montpellier Cedex 5, France
| | - Frank M Schurr
- Institute of Landscape and Plant Ecology, University of Hohenheim, 70593 Stuttgart, Germany
| | - Len Thomas
- Centre for Research into Ecological and Environmental Modelling, University of St Andrews, St Andrews KY16 9LZ, UK
| | - Wilfried Thuiller
- Laboratoire d'Ecologie Alpine, UMR CNRS 5553, Université Joseph Fourier, Grenoble I, BP 53, 38041 Grenoble Cedex 9, France
| | - Verena Trenkel
- Ifremer, Rue de l'île d'Yeu, BP 21105, 44311 Nantes Cedex 3, France
| | - Perry de Valpine
- Environmental Science, Policy and Management, University of California, Berkeley, CA 94720, USA
| | - Eric Rexstad
- Centre for Research into Ecological and Environmental Modelling, University of St Andrews, St Andrews KY16 9LZ, UK
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Lecomte JB, Benoît HP, Ancelet S, Etienne MP, Bel L, Parent E. Compound Poisson-gamma vs. delta-gamma to handle zero-inflated continuous data under a variable sampling volume. Methods Ecol Evol 2013. [DOI: 10.1111/2041-210x.12122] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Jean-Baptiste Lecomte
- INRA; UMR 518 Math. Info. Appli.; Paris F-75005 France
- AgroParisTech; UMR 518 Math. Info. Appli.; Paris F-75005 France
| | - Hugues P. Benoît
- Gulf Fisheries Centre; Fisheries and Oceans Canada; Moncton NB E1C 9B6 Canada
| | - Sophie Ancelet
- Institut de Radioprotection et de Sûreté Nucléare; Laboratoire d'épidémiologie; Fontenay-aux-Roses France
| | - Marie-Pierre Etienne
- INRA; UMR 518 Math. Info. Appli.; Paris F-75005 France
- AgroParisTech; UMR 518 Math. Info. Appli.; Paris F-75005 France
| | - Liliane Bel
- INRA; UMR 518 Math. Info. Appli.; Paris F-75005 France
- AgroParisTech; UMR 518 Math. Info. Appli.; Paris F-75005 France
| | - Eric Parent
- INRA; UMR 518 Math. Info. Appli.; Paris F-75005 France
- AgroParisTech; UMR 518 Math. Info. Appli.; Paris F-75005 France
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Simon M, Fromentin JM, Bonhommeau S, Gaertner D, Brodziak J, Etienne MP. Effects of stochasticity in early life history on steepness and population growth rate estimates: an illustration on Atlantic bluefin tuna. PLoS One 2012; 7:e48583. [PMID: 23119063 PMCID: PMC3485314 DOI: 10.1371/journal.pone.0048583] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Accepted: 10/03/2012] [Indexed: 11/19/2022] Open
Abstract
The intrinsic population growth rate (r) of the surplus production function used in the biomass dynamic model and the steepness (h) of the stock-recruitment relationship used in age-structured population dynamics models are two key parameters in fish stock assessment. There is generally insufficient information in the data to estimate these parameters that thus have to be constrained. We developed methods to directly estimate the probability distributions of r and h for the Atlantic bluefin tuna (Thunnus thynnus, Scombridae), using all available biological and ecological information. We examined the existing literature to define appropriate probability distributions of key life history parameters associated with intrinsic growth rate and steepness, paying particular attention to the natural mortality for early life history stages. The estimated probability distribution of the population intrinsic growth rate was weakly informative, with an estimated mean r = 0.77 (±0.53) and an interquartile range of (0.34, 1.12). The estimated distribution of h was more informative, but also strongly asymmetric with an estimated mean h = 0.89 (±0.20) and a median of 0.99. We note that these two key demographic parameters strongly depend on the distribution of early life history mortality rate (M(0)), which is known to exhibit high year-to-year variations. This variability results in a widely spread distribution of M(0) that affects the distribution of the intrinsic population growth rate and further makes the spawning stock biomass an inadequate proxy to predict recruitment levels.
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Affiliation(s)
- Maximilien Simon
- AgroParistech-ENGREF (École Nationale du Génie Rural des Eaux et des Forêts), Paris, France.
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