Géraldine Lassalle

French National Institute for Agriculture, Food, and Environment (INRAE) | INRAE · Aqua Department

Introduction Many diadromous fish species are currently facing the threat of generalized population extirpations across their range, and conservation efforts implemented primarily within the continental domain may not be sufficient to ensure their viability. In consequence, better understanding the use of the marine environment by these species tur...

Marine-estuarine opportunist (MEO) species are fish that occur in the continental shelf and use estuaries and/or shallow coastal areas as nurseries. These commercially important resources are facing significant environmental modifications caused by direct and/or indirect anthropogenic climate change effects. In this study, we investigated the direc...

Increasing knowledge on distribution and habitat selection of coastal fish species is essential for the management of marine environments, and can be provided through the use of Species Distribution Models (SDM). Opportunistic and participatory data such as recreational or commercial bycatch data can provide precious information at large scale and...

Marine-estuarine opportunist (MEO) species are fish that occur in the continental shelf and use estuaries and/or shallow coastal areas as nurseries. These commercially important resources are facing significant environmental modifications caused by direct and/or indirect anthropogenic climate change effects. In this study, we investigated the direc...

Diadromous species are particularly vulnerable to climate change because they utilize both marine and freshwater habitat to complete their life cycles. Dispersal plays an important role in restraining the distribution of plant and animal species, and is a key mechanism to allow diadromous species to adapt to changes in habitat suitability, but it i...

The consequences of climate change for marine organisms are now well-known, and include metabolism and behavior modification, distribution area shifts and changes in the community. In the Bay of Biscay, the potential environmental niches of subtropical non-indigenous species (NIS) are projected to expand as a response to sea temperature rise by the...

EuroDiad version 4.0 is a set of data tables that store information about the presences/absences and population functionality of diadromous species (lampreys and fish) populations in selected catchments in Europe, the Middle East, and North Africa from 1750 to present time. This database contains distribution and life-history trait information for...

We developed the HoOS simulator (Hasty or Omniscient Shads) to assess how upstream migration and reproductive timings influence allis shad Alosa alosa (Linnaeus, 1758) temperature-dependent survival of early-life stages. We tested the influence of two reproductive timings depending on whether spawners can synchronize their spawning activity (i.e.,...

Lampreys are jawless fishes that evolved hundreds of millions of years ago and exhibit multiple and varied life history strategies. Rapid changes in the current climate are clear, and warming temperatures and changes in precipitation patterns over the past several decades are projected to continue into the foreseeable future. The effects of our cha...

chocR is a package for the R software to perform choc analyses. Choc analysis aims at detecting variations of occurrences (increase or decrease) of events in multivariate time series. In other words, here is a method to examine joint monotonic trends in multivariate time series. By taking into account the occurrence of a key event in the life cycle...

Diadromous species act as nutrient vectors between their marine and freshwater habitats. Few valuations of this regulating service exist and none at the scale of species distribution ranges. This large-scale approach seems particularly relevant for species moving and exchanging individuals across borders and territories as these populations may str...

Most key life-events of organisms are synchronized by complex interactions of several environmental cues to ensure optimal survival and growth of individuals and their offspring. However, global change is known to affect multiple components of ecosystems and cues at the same time. Therefore, detecting joint trends in covariate time series is a cruc...

Diadromous (land-sea migrating) species are declining due to the cumulative effect of local anthropogenic pressures and climate change, threatening the ecosystem services provided to local human communities (Limburg and Waldman, 2009). In particular, these species transport nutrients and carbon subsidies through their migrations between marine and...

During the last decades, the highly-anthropized Seine estuary has been impacted by modification of its habitats (building of a major extension of Le Havre harbour, i.e. Port2000) and a significant natural decrease in freshwater discharge. A Before/After analysis, using a toolbox of indicators, was applied to characterize the effects of both events...

At the interface between terrestrial and marine biomes, estuaries display high ecological productivity and provide goods and services to humans. Associated with many ecological functions, they are nursery, refuge, and growing areas for many species fish. These ecological functions and services depend on both their ecological production and trophic...

Climate, by altering the spatio-temporal distributions of suitable habitats, leads to modifications in a multitude of species ranges. In recent years, the ability of species to adjust to changing climatic conditions is of growing concern. In the present study, a generic trait-based method to assess species exploratory potential under climate change...

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...

As species biology and ecology is profoundly influenced by climate, any climatic alteration may have severe consequences on marine pelagic ecosystems and their food webs. It remains challenging to estimate the influence of climate on both structural and functional properties of food webs. In this study, we proposed an innovative approach to assess...

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...

Ecological network analysis (ENA) provides numerous ecosystem level indices offering a valuable approach to compare and categorize the ecological structure and function of ecosystems. The inclusion of ENA methods in Ecopath with Ecosim (EwE) has insured their continued contribution to ecosystem-based management. In EwE, ENA-derived ecological concl...

Species can respond to climate change by tracking appropriate environmental conditions in space, resulting in a range shift. Species Distribution Models (SDMs) can help forecast such range shift responses. For few species, both correlative and mechanistic SDMs were built, but allis shad (Alosa alosa), an endangered anadromous fish species, is one o...

The European Union's Marine Strategy Framework Directive (MSFD) seeks to achieve, for all European seas, " Good Environmental Status " (GEnS), by 2020. Ecological models are currently one of the strongest approaches used to predicting and understanding the consequences of anthropogenic and climate-driven changes in the natural environment. We asses...

Ecosystem models are currently one of the most powerful approaches used to project and analyse the consequences of anthropogenic and climate-driven changes in food web structure and function. The modeling community is however still finding the effective representation of microbial processes as challenging and lacks of techniques for assessing flow...

Around 2000, the anadromous allis shad population in the Garonne basin (southwest France) was the largest in Europe. During the first decade of the 21st century, catches dramatically declined and led to a fishery moratorium in 2008. In a first modelling study, the high estuarine mortalities combined with a demographic Allee effect in the reproducti...

Lassalle, G., Nelva Pasqual, J-S., Boët, P., Rochet, M-J., Trenkel, V. M., and Niquil, N. Combining quantitative and qualitative models to identify functional groups for monitoring changes in the Bay of Biscay continental shelf exploited foodweb. – ICES Journal of Marine Science, 71: . To develop and implement ecosystem-based management, it is crit...

The purpose of this report is to review the current capabilities of the modelling community to inform on indicators outlined in the Marine Strategy Framework Directive (MSFD), for biodiversity (D1), and food webs (D4) and, where possible, also non-indigenous species (D2) and seafloor integrity (D6). Where models are available to the DEVOTES projec...

Lassalle, G., Lobry, J., Le Loc'h, F., Mackinson, S., Sanchez, F., Tomczak, M. T., and Niquil, N. 2013. Ecosystem status and functioning: searching for rules of thumb using an intersite comparison of food-web models of Northeast Atlantic continental shelves. – ICES Journal of Marine Science, 70:135–149. This work aimed to provide a better understan...

Cockles (Cerastoderma edule) are among the most exploited bivalves in Europe. They live in lagoons and estuaries where they undergo many stressors including parasites. Trematodes are the most prevalent macroparasites of cockles and can exert a significant impact on their host populations depending on parasite species and infection intensity. Monito...

Lassalle, G., Gascuel, D., Le Loc'h, F., Lobry, J., Pierce, G. J., Ridoux, V., Santos, M. B., Spitz, J., and Niquil, N. 2012. An ecosystem approach for the assessment of fisheries impacts on marine top predators: the Bay of Biscay case study. – ICES Journal of Marine Science, 69: 925–938. A number of marine mammal populations is currently threatene...

In the mid-nineteenth century, the European sturgeon (Acipenser sturio L, 1758) was proved to have been present in a significant proportion of the Western Palearctic region, i.e., Europe and North Africa. Of the 196 basin units investigated, 24 were selected for spawning by sexually mature individuals, and 44 were frequented by occasional vagrants....

The restoration of threatened species is taking place in a changing global environment, creating additional problems for stakeholders and decision-makers to face. Here, the potential influences on the restoration measures developed for the European sturgeon (Acipenser sturio L., 1758) of both climate change and, to a lesser extent, biological intro...

Due to anthropogenic actions, species have become endangered or have been driven to the verge of extinction, requiring conservation plans to be developed and implemented. These plans include measures to protect and enhance remaining populations and to reintroduce populations within the native ranges. However, future habitat suitability in the face...

La conservation de la biodiversité est un concept récent qui s'appuie pourtant pour l'essentiel sur des directives européennes ou des conventions internationales qui ne considèrent pas la dynamique des systèmes écologiques. Jusqu'à lors, il s'agissait donc de retrouver une situation antérieure jugée plus satisfaisante pour une espèce, un habitat ou...

Climate change can have an effect on species distributions. The 1900 distribu-tion and potential future distribution of diadromous fish in Europe, North Africa, and the Middle East were explored using generalized additive models (GAMs) and selected habitat characteristics of 196 basins. Robust presence–absence models were built for 20 of the 28 dia...

1. Twenty‐eight diadromous fish species occurred in Europe, North Africa and the Middle East in historical times. Their current distributions were assessed in terms of abundance classes (missing, rare, common and abundant) in 196 basins ranging from Morocco to northern Norway and from Greenland to Iran. 2. Their current distributions were modelled...

Age and total length (LT) at maturity of allis shad Alosa alosa exhibited a significant negative latitudinal gradient over the species’ distribution range. Particular thermal conditions experienced over the distribution area could be the key factor involved to explain this negative trend.

Climate change is expected to drive species ranges towards the poles and to have a strong influence on species distributions. In this study, we focused on diadromous species that are of economical and ecological importance in the whole of Europe. We investigated the potential distribution of all diadromous fish regularly encountered in Europe, Nort...

Most of the European diadromous fish species are endangered and listed in the habitats fauna and flora directive, the bern convention and the IUCN Red List. Current conservation plans do not address global warming issues and consider the 1900 distribution range as the reference without taking into account the potential re-distribution of these spec...

Among the potential biotic factors affecting population dynamics, parasitism has received relatively little attention. The purpose of this study was to inventory marine bivalve parasites and to investigate relations between different parasite communities. Five intertidal stations along the French Atlantic shore were studied between Brittany and Arc...