Bruno Ernande

Bruno Ernande
Institut Français de Recherche pour l'Exploitation de la Mer | Ifremer · UMR MARBEC (MARine Biodiversity, Exploitation and Conservation)

PhD

About

87
Publications
22,029
Reads
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4,804
Citations
Additional affiliations
September 2020 - May 2021
Institut Français de Recherche pour l'Exploitation de la Mer
Position
  • Senior Researcher
September 2016 - September 2020
Institut Français de Recherche pour l'Exploitation de la Mer
Position
  • Consultant
January 2016 - August 2020
Institut Français de Recherche pour l'Exploitation de la Mer
Position
  • Senior Researcher
Education
September 1997 - September 2001
La Rochelle Université
Field of study
  • Marine Evolutionary Ecology
September 1996 - September 1997
Sorbonne Université
Field of study
  • Evolutionary Ecology
September 1994 - September 1998
Ecole Normale Supérieure de Paris
Field of study
  • Biology-Biochemistry

Publications

Publications (87)
Article
Growth is a key component of population dynamics and, thus, fisheries management, yet drivers of its variations are often poorly understood. Using individual data collected over 80 years, we explored how environmental drivers affect growth in a major population of Atlantic herring (Clupea harengus). The results confirm that intrinsic factors (age a...
Article
Full-text available
This study addresses the temporal variability of couplings between pelagic and benthic habitats for fish assemblages at five periods in a shallow epicontinental sea, the Eastern English Channel (EEC). Organic matter fluxes fueling fish assemblages and the relative contribution of their different sources were assessed using stable isotope analysis a...
Article
Full-text available
The otolith, found in both inner ears of bony fish, has mainly been used to estimate fish age. Another application that has been developing significantly in recent years, however, is the use of otolith shape as a tool for stock identification. Often, studies have directly used the shape asymmetry between the right and left otoliths. We tested the m...
Article
The extant coelacanth was discovered in 1938;¹ its biology and ecology remain poorly known due to the low number of specimens collected. Only two previous studies¹,² have attempted to determine its age and growth. They suggested a maximum lifespan of 20 years, placing the coelacanth among the fastest growing marine fish. These findings are at odds...
Article
Full-text available
Marine organisms show population structure at a relatively fine spatial scale, even in open habitats. The tools commonly used to assess subtle patterns of connectivity have diverse levels of resolution and can complement each other to inform on population structure. We assessed and compared the discriminatory power of genetic markers and otolith sh...
Article
As part of the energy transition, the French government is planning Offshore Wind Farm (OWF) constructions in the next decades. An integrated ecosystem approach of two future OWF sites of the Eastern English Channel (Courseulles-sur-mer and Dieppe-Le Tréport) was developed to model the marine ecosystems before the OWF implementation. Such ecosystem...
Article
Full-text available
Otolith shape analysis is an efficient fish stock identification tool. However, most applications used left and right otoliths or only one of them arbitrarily chosen without testing for biases resulting from potential directional bilateral asymmetry (DA) in otolith shape, i.e., a unimodal population-level deviation form bilateral symmetry between r...
Article
A combination of modelling tools was applied to simulate the impacts of the future Courseulles-sur-mer offshore wind farm (OWF) construction (Bay of Seine, English Channel) on the ecosystem structure and functioning. To do so, food-web models of the ecosystem under three scenarios were constructed to investigate the effect caused by the OWF of adde...
Poster
Full-text available
European anchovy, Engraulis encrasicolus, is a small pelagic coastal marine fish largely spread from the North Sea to central Africa, including the entire Mediterranean and the Black and Azov Seas. The aim of this study is to identify the potential different populations of European anchovies and their relationship between the Northeast Atlantic, th...
Article
Environmental conditions, to which organisms are exposed during all their life, may cause possible adaptive responses with consequences in their subsequent life-history trajectory. The objective of this study was to investigate whether ecologically relevant combinations of hypoxia (40% and 100% air saturation) and temperature (15° and 20 °C), occur...
Article
Full-text available
There is a growing need to easily describe and synthesize the dynamics of ecosystems’ components in space and time. Most multivariate analyses provide ordination diagrams or biplots that are too cluttered to allow simple reading and are unfamiliar to most users. To overcome such difficulties, a novel application of principal response curves (PRCs)...
Article
Whether considered as a risk for human health or as ecological tracers, contaminants' concentrations measured in fish muscles are commonly expressed relative to wet or dry mass. Comparison of results required conversion factors (CF) but accurate values are scarce and case-specific. The present paper is aimed at investigating errors linked with the us...
Article
Polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are persistent organic pollutants that have been shown to affect fish life-history traits such as reproductive success, growth and survival. At the individual level, their toxicity and underlying mechanisms of action have been studied through experimental exposure. However,...
Article
Stock structure of whiting (Merlangius merlangus) in the North East Atlantic is unclear. This study uses mixed effects models to analyse growth variability as a way to investigate stock identification. Growth trajectories for 634 individuals and length-at-age data for 78,686 individuals were analysed for spatial coherence and temporal synchrony in...
Article
Depth is one of the environmental variables influencing the structure of marine food webs by directly or indirectly influencing benthic-pelagic coupling and predator-prey relationships. In shallow waters, the high degree of connectivity between pelagic and benthic networks results in complex systems with multiple interactions. Digestive tract (DT)...
Article
Full-text available
Spatial and temporal variations in gill and palp size were studied during 1 year in naturally-settled populations of the Pacific oyster Crassostrea gigas, reciprocally transplanted between two contrasting sites located along a marked gradient of turbidity conditions. The variability of suspended particulate matter (SPM) and food particles, estimate...
Article
Full-text available
The European eel (Anguilla anguilla), and generally, temperate eels, are relevant species for studying adaptive mechanisms to environmental variability because of their large distribution areas and their limited capacity of local adaptation. In this context, GenEveel, an individual-based optimization model, was developed to explore the role of adap...
Article
Full-text available
Individual diet variation (i.e. diet variation among individuals) impacts intra-and inter-specific interactions. Investigating its sources and relationship with species trophic niche organization is important for understanding community structure and dynamics. Individual diet variation may increase with intra-specific phenotypic (or " individual st...
Presentation
Full-text available
Few studies have documented large-scale variations of trophic relationships along environmental gradients, especially in marine ecosystems, despite this topic being recognized as critical for food-web functioning understanding. Recent theoretical work demonstrated the importance of bentho-pelagic coupling in shaping the structure and functioning of...
Article
Full-text available
Previous studies have shown that the amount of food influences fish otolith structure, opacity and shape and that diet composition has an effect on otolith chemical composition. This study investigated the potential correlation between diet and otolith shape in 5 wild marine fish species by addressing 4 complementary questions. First, is there a gl...
Article
As part of the energy transition, the French government is planning the construction of three offshore wind farms in Normandy (Bay of Seine and eastern part of the English Channel, north-western France) in the next years. These offshore wind farms will be integrated into an ecosystem already facing multiple anthropogenic disturbances such as mariti...
Presentation
Full-text available
Trophic networks are complex systems, with interactions at different levels that controls ecosystem functioning. They are also under the control of abiotic parameters, such as depth, that drive organic matter fluxes. Thus, it can be useful to combine contaminants with classic trophic markers (such as C and N stable isotopes) to track organic matter...
Technical Report
Full-text available
Saithe (Pollachius virens), the most landed demersal species in the North Sea, has seen its Spawning Stock Biomass decrease in the most recent years notwithstanding an exploitation at sustainable level (ICES, 2014). This recent decline follows a decrease of North Sea saithe mean weight-at-age (particularly for older ages) and might result, at least...
Article
Full-text available
This study investigated and compared asymmetry in sagittal otolith shape and length between left and right inner ears in four roundfish and four flatfish species of commercial interest. For each species, the effects of ontogenetic changes (individual age and total body length), sexual dimorphism (individual sex) and the otolith's location on the ri...
Article
Full-text available
Identifying the various drivers of marine ecosystem regime shifts and disentangling their respective influence are critical tasks for understanding biodiversity dynamics and properly managing exploited living resources such as marine fish communities. Unfortunately, the mechanisms and forcing factors underlying regime shifts in marine fish communit...
Article
Full-text available
North Sea saithe Pollachius virens, a major top predator in the area, supports the fishery economy of several European countries. However, recent stock assessments suggested a decrease in spawning stock biomass along with a decline in saithe mean weight-at-ages. In this context, we investigated North Sea saithe growth characteristics at the populat...
Article
Full-text available
Fishing may induce neutral and adaptive evolution affecting life-history traits, and molecular evidence has shown that neutral genetic diversity has declined in some exploited populations. Here we theoretically study the interplay between neutral and adaptive evolution caused by fishing. An individual-based eco-genetic model is devised that include...
Article
Full-text available
Younger ages and smaller sizes at maturation have been observed in commercial fish stocks over the last century. We establish that age and length at 50% proportion mature (i.e. the proportion of mature individuals in a population or the probability that an individual is mature) decreased from the 1970s to the 2000s in North Sea cod Gadus morhua, ha...
Book
Full-text available
This document is a comprehensive survey of the scientific knowledge acquired in late 2012 on the environmental impacts of marine aggregate extraction. The synthesis completes international knowledge (ICES WGEXT, COST Action 638 "MAGGNET") with local investigation in Normandy on two sites of the eastern English Channel in the framework of the 2003-2...
Article
Full-text available
Managing fisheries resources to maintain healthy ecosystems is one of the main goals of the ecosystem approach to fisheries (EAF). While a number of international treaties call for the implementation of EAF, there are still gaps in the underlying methodology. One aspect that has received substantial scientific attention recently is fisheries-induce...
Article
Latitudinal variation in life-history traits is often explained by phenotypically plastic responses or local adap-tations to different thermal regimes. We compared growth, maturation schedules and reproductive invest-ment of female sole Solea solea between 8 populations, covering much of the species' distribution in northern Europe, with respect to...
Article
Full-text available
Human societies, and their well-being, depend to a significant extent on the state of the ecosystems that surround them. These ecosystems are changing rapidly usually in response to anthropogenic changes in the environment. To determine the likely impact of environmental change on ecosystems and the best ways to manage them, it would be desirable t...
Article
Biological reference points are important tools for fisheries management. Reference points are not static, butmay change when a population’s environment or the population itself changes. Fisheries-induced evolution is one mechanism that can alter population characteristics, leading to “shifting” reference points by modifying the underlying biologic...
Article
Full-text available
An individual's environmental history may have delayed effects on its physiology and life history at later stages in life because of irreversible plastic responses of early ontogenesis to environmental conditions. We chose a marine fish, the common sole, as a model species to study these effects, because it inhabits shallow marine areas highly expo...
Article
Full-text available
Managing fisheries resources to maintain healthy ecosystems is one of the main goals of the ecosystem approach to fisheries (EAF). While a number of international treaties call for the implementation of EAF, there are still gaps in the underlying methodology. One aspect that has received substantial scientific attention recently is fisheries-induce...
Article
Full-text available
A new method is presented to estimate individuals' (1) age at maturation, (2) energy acquisition rate, (3) energy expenditure for body maintenance, and (4) reproductive investment, and the multivariate distribution of these traits in a population. The method relies on adjusting a conceptual energy allocation model to individual growth curves using...
Conference Paper
Full-text available
The structure, dynamics and productivity of marine ecosystems depend mainly on their underlying food webs. Marine food web structure can be partly characterized by fish species' trophic level. Trophodynamics studies often highlight size-related ontogenetic shifts in the diet of marine fishes, implying an increase of the trophic level according to f...
Article
Full-text available
The Channel Habitat Atlas for Marine Resource Management (CHARM) is a trans-border collaboration project between France and United Kingdom. It has become, since 2003, a growing network of scientists geared on investing in science through joint collaboration, communication and knowledge management. The initial objective of the project is to provide...
Article
Full-text available
Maturation age and size have important fitness consequences through their effects on survival probabilities and body sizes. The evolution of maturation reaction norms in response to environmental covariation in growth and mortality is therefore a key subject of life-history theory. The eco-evolutionary model we present and analyze here incorporates...
Article
Full-text available
The eastern English Channel, which connects the Atlantic Ocean to the North Sea through the Dover Strait, is an area where numerous and often conflicting human activities take place. A cross-border multidisciplinary project called CHARM was initiated to provide knowledge and tools for planners and decision-makers to durably manage the shared marine...
Article
the eastern english Channel, which connects the atlantic ocean to the north Sea through the dover Strait, is an area where numerous and often conflicting human activities take place. A cross-border multidisciplinary project called CHARM was initiated to provide knowledge and tools for planners and decision-makers to durably manage the shared marine...
Article
We present a new methodology to estimate rates of energy acquisition, maintenance, reproductive investment and the onset of maturation (four-trait estimation) by fitting an energy allocation model to individual growth trajectories. The accuracy and precision of the method is evaluated on simulated growth trajectories. In the deterministic case, all...
Article
Full-text available
Early reproductive effort and growth were measured in 3 groups of the Pacific oyster Crassostrea gigas: 1 diploid group and 2 triploid groups resulting from either chemical induction (3nCB) or crosses between tetraploid and diploid parents (3nDT). Oysters were reared under intensive nursery conditions and sampled when 5 mo old. Reproductive effort...
Article
Full-text available
The eastern English Channel, the narrow channel of water separating northern France and southeast England is an area of intense human use of the array of resources concentrated into its relative small area. The vulnerability of living resources and their habitats brought together French and British maritime experts within a common project (called C...
Article
Full-text available
The use of genetic, biochemical and electronic markers in population biology and ecology has been growing tremendously during the last two decades. The first part of this paper aims at reviewing the main principles and advances of these individual markers through a few key applications on exploited marine fish populations. The second part is more p...
Article
Full-text available
Industrial fishing has been identified as a cause for life history changes in many harvested stocks, mainly because of the intense fishing mortality and its size-selectivity. Because these changes are potentially evolutionary, we investigate evolutionarily stable life-histories and yield in an energy-allocation state-dependent model for Northeast A...
Article
Full-text available
The use of genetic, biochemical and electronic markers in population biology and ecology has been growing tremendously during the last two decades. The first part of this paper aims at reviewing the main principles and advances of these individual markers through a few key applications on exploited marine fish populations. The second part is more p...
Article
Full-text available
In their Policy Forum (“Managing evolving fish stocks,” 23 November 2007, p. [1247][1]), C. Jorgensen et al. propose evolutionary impact assessments (EvoIAs) as a general tool for managing evolving resources. The basis for their proposal is that fisheries-induced evolution (FIE) is the most