Margaux Mathieu-Resuge

Institut Français de Recherche pour l'Exploitation de la Mer | Ifremer · Department of Deep-Sea Ecosystems

Human land-use intensification threatens arthropod (for example, insect and spider) biodiversity across aquatic and terrestrial ecosystems. Insects and spiders play critical roles in ecosystems by accumulating and synthesizing organic nutrients such as polyunsaturated fatty acids (PUFAs). However, links between biodiversity and nutrient content of...

Juveniles of large hammerhead shark species occupy coastal nurseries before migrating offshore to reproduce. In the central Gulf of California, artisanal elasmobranch fisheries have reported catches of juvenile scalloped Sphyrna lewini and smooth S. zygaena hammerhead sharks, but their local foraging habits are yet to be fully understood. In this s...

Morphometric indices of body condition are assumed to reflect an animal’s health and ultimately its fitness, but their physiological significance remains a matter of debate. These indices are indeed usually considered as proxies of energy reserves, ignoring other physiological processes involved in animal health such as nutritional, immune and horm...

High temperature increases energy demand in ectotherms, limiting their physiological capability to cope with hypoxic events. The present study aimed to assess the metabolic tolerance of juvenile Nodipecten subnodosus scallops to acute hyperthermia combined with moderate hypoxia. A previous study showed that juveniles exhibited a high upper temperat...

The use of microalgae as a sustainable source of n-3 long-chain polyunsaturated fatty acids (LC-PUFA) as an alternative to fish oils from small pelagic fish (e.g., anchovy, sardine) has received growing interest in the past few years. The present study aimed to: (i) produce Aurantiochytrium mangrovei biomass by heterotrophic fermentation using a me...

Unlabelled: Fishponds, despite being globally abundant, have mainly been considered as food production sites and have received little scientific attention in terms of their ecological contributions to the surrounding terrestrial environment. Emergent insects from fishponds may be important contributors of lipids and essential fatty acids to terres...

The physiological dependence of animals on dietary intake of vitamins, amino acids, and fatty acids is ubiquitous. Sharp differences in the availability of these vital dietary biomolecules among different resources mean that consumers must adopt a range of strategies to meet their physiological needs.We review the emerging work on omega-3 long-chai...

Permanent ponds are valuable freshwater systems and biodiversity hotspots. They provide diverse ecosystem services (ES), including water quality improvement and supply, food provisioning and biodiversity support. This is despite being under significant pressure from multiple anthropogenic stressors and the impacts of ongoing global change. However,...

Emergent insects represent a key vector through which aquatic nutrients are transferred to adjacent terrestrial food webs. Aquatic fluxes of polyunsaturated fatty acids (PUFA) from emergent insects are particularly important subsidies for terrestrial ecosystems due to high PUFA contents in several aquatic insect taxa and their physiological importa...

Omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) are essential micronutrients for aquatic consumers. Synthesized by aquatic primary producers, n-3 LC-PUFA are transferred across trophic levels and may eventually end up accumulating in fish. However, if short in dietary supply, fish may also biosynthesize n-3 LC-PUFA from dietary precurs...

Climate change can decouple resource supply from consumer demand, with the potential to create phenological mismatches driving negative consequences on fitness. However, the underlying ecological mechanisms of phenological mismatches between consumers and their resources have not been fully explored. Here, we use long-term records of aquatic and te...

Organisms at the base of aquatic food webs synthesize essential nutrients, such as omega‐3 polyunsaturated fatty acids (n‐3 PUFA), which are transferred to consumers at higher trophic levels. Many consumers, requiring n‐3 long‐chain (LC) PUFA, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have limited ability to biosynthesize...

Consumers feeding at the aquatic–terrestrial ecosystem interface may obtain a mixture of aquatic and terrestrial diet resources that vary in nutritional composition. However, in lake riparian spiders, the relative significance of aquatic versus terrestrial diet sources remains to be explored. We investigated the trophic transfer of lipids and polyu...

• The ecological role of emergent aquatic insects from lakes in exporting dietary polyunsaturated fatty acids (PUFA) across the freshwater-land interface is still poorly understood. • In this field study, we explored the seasonal biomass export of emergent insects from three subalpine lakes and investigated how lipids of emergent insects were relat...

Across ecosystems, resources vary in their nutritional composition and thus their dietary value to consumers. Animals can either access organic compounds, such as fatty acids, directly from diet or through internal biosynthesis, and the extent to which they use these two alternatives likely varies based on the availability of such compounds across...

Carbon isotopic fractionation was studied during the development of the diatom Chaetoceros muelleri grown in batch culture with ¹³C-depleted CO2 addition. Cellular and growth parameters and isotopic composition of dissolved inorganic carbon and particulate organic carbon were monitored every two days, while the content and isotopic composition of i...

An important, but underappreciated, consequence of climate change is the reduction in crucial nutrient production at the base of the marine food chain: the long-chain omega-3 highly unsaturated fatty acids (n-3 HUFA). This can have dramatic consequences on consumers, such as fish as they have limited capacity to synthesise n-3 HUFA de novo. The n-3...

Bivalves' physiological functions (i.e. growth, reproduction) are influenced by environmental variability that can be concomi-tant with trophic resource variations in terms of quality and quantity. Among the essential molecules that bivalves need to acquire from their diet to maintain physiological functions, fatty acids (FAs) such as polyunsaturat...

Determining the lipid content and fatty acid (FA) composition of aquatic organisms has been of major interest in trophic ecology, aquaculture, and nutrition for over half a century. Although protocols for lipid analysis are well-described, their application to aquatic sciences often requires modifications to adapt to field conditions and to sample...

Deposit-feeding sea cucumbers are efficient nutrient recyclers and have the potential to contribute to the limitation of organic matter load in polyculture or integrated aquaculture systems. Assessing how they assimilate organic matter originating from other farmed species is therefore important for the development of such multi-species farming sys...

Emerging aquatic insects (EAI) are important vectors through which freshwater-derived organic matter can enter terrestrial food webs. Aquatic-derived dietary energy can support terrestrial consumer fitness, especially via its polyunsaturated fatty acids (PUFA) that are otherwise short in supply from terrestrial diet. Considering qualitative aspects...

The trophic fate of various food sources is of central interest for ecologists, yet not well understood in coastal lagoon food webs. In this field study, fatty acids (FA), stable isotopes (SI), and compound-specific isotopic analysis (CSIA) on FA were used to investigate how diets from oceanic and local sources are retained in a bivalve species (Sp...

Poster highlighting my PhD objective and first results. Presented in 2019 at the University of North Carolina Wilmington (UNCW) in the Center for Marine Sciences (CMS) for the Graduate Student Day. Final results for the C. neogracile and A. minutum experiments have been published in Biomolecules in 2020.

Understanding the nature and origins of food sources supporting coastal lagoon-inhabiting organisms is necessary to evaluate the ecological status of such ecosystems. The trophic ecology of a bivalve species Spondylus crassisquama was studied in the Ojo de Liebre lagoon (Baja California, Mexico), combining stable isotope (SI), fatty acid (FA) and s...

Les lagunes côtières sont des écosystèmes semi-fermés à l'interface de la terre et des océans et sous l'influence de ces deux compartiments. De par ces caractéristiques, elles sont soumises à de fortes variations spatiales et saisonnières de leurs ressources trophiques. De par leur nature fermée et peu profonde, elles vont amplifier la force des pr...

Notre étude a permis d’établir un modèle conceptuel des principaux paramètres régissant l’aquaculture d’holothuries en bassin et en milieu côtier. Ce modèle doit maintenant être testé et validé grâce à de nouvelles expérimentations afin de mettre en place des protocoles d’élevages performants qui sont nécessaires pour mener cette filière naissante...