217 results match your criteria: "UMR 7372-CNRS & Universite de la Rochelle[Affiliation]"

The relationship between the environment and marine animal small-scale behavior is not fully understood. This is largely due to the difficulty in obtaining environmental datasets with a high spatiotemporal precision. The problem is particularly pertinent in assessing the influence of environmental factors in rapid, high energy-consuming behavior such as seabird take-off.

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Keystone seabird may face thermoregulatory challenges in a warming Arctic.

Sci Rep

October 2023

Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 2 Rue Olympe de Gouges, 17000, La Rochelle, France.

Climate change affects the Arctic more than any other region, resulting in evolving weather, vanishing sea ice and altered biochemical cycling, which may increase biotic exposure to chemical pollution. We tested thermoregulatory impacts of these changes on the most abundant Arctic seabird, the little auk (Alle alle). This small diving species uses sea ice-habitats for foraging on zooplankton and resting.

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Seasonal variations of testis anatomy and of G-coupled oestrogen receptor 1 expression in Gerbillus gerbillus.

Anat Histol Embryol

November 2023

UMRS 449, Laboratory of General Biology, Catholic University of Lyon, Reproduction and Comparative Development/EPHE, University of Lyon, Lyon, France.

Article Synopsis
  • The study focuses on the seasonal reproductive changes in the gerbil (Gerbillus gerbillus), particularly in male anatomy and behavior during breeding and resting seasons.
  • During the breeding season, the testes are active with abundant sperm, and there is high expression of the G-protein-coupled oestrogen receptor 1 (GPER1) in several cell types, indicating intense spermatogenesis.
  • In contrast, the resting season sees a significant reduction in testicular weight, halting of sperm production, and a changed expression pattern of GPER1, suggesting its key role in regulating these seasonal reproductive cycles.
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Assessing the determinants of reproductive success is critical but often complicated because of complex interactions between parental traits and environmental conditions occurring during several stages of a reproductive event. Here, we used a simplified ecological situation-an amphibian species lacking post-oviposition parental care-and a laboratory approach to investigate the relationships between parental (both maternal and paternal) phenotypes (body size and condition) and reproductive success (fecundity, egg size, embryonic and larval duration, larval and metamorphic morphology). We found significant effects of maternal phenotype on fecundity, hatching success, and tadpole size, as well as on the duration of larval development.

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Mercury (Hg) pollution is a global problem affecting remote areas of the open ocean, but the bioaccumulation of this neurotoxic pollutant in tropical top predators remains poorly documented. The objective of this study was to determine Hg contamination of the seabird community nesting on Clipperton Island using blood and feathers to investigate short and longer-term contamination, respectively. We examined the significance of various factors (species, sex, feeding habitat [δC] and trophic position [δN]) on Hg concentrations in six seabird species.

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Amidst the current biodiversity crisis, the availability of genomic resources for declining species can provide important insights into the factors driving population decline. In the early 1990s, the black-legged kittiwake (Rissa tridactyla), a pelagic gull widely distributed across the arctic, subarctic, and temperate zones, suffered a steep population decline following an abrupt warming of sea surface temperature across its distribution range and is currently listed as Vulnerable by the International Union for the Conservation of Nature. Kittiwakes have long been the focus for field studies of physiology, ecology, and ecotoxicology and are primary indicators of fluctuating ecological conditions in arctic and subarctic marine ecosystems.

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Large-scale breeding failures, such as offspring die-offs, can disproportionately impact wildlife populations that are characterized by a few large colonies. However, breeding monitoring-and thus investigations of such die-offs-is especially challenging in species with long reproductive cycles. We investigate two unresolved dramatic breeding failures that occurred in consecutive years (2009 and 2010) in a large king penguin Aptenodytes patagonicus colony, a long-lived species with a breeding cycle lasting over a year.

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Variation of 210-polonium in the cephalopod community from the Bay of Biscay, North-East Atlantic.

J Environ Radioact

November 2023

Centro de Estudios Ambientales de Cienfuegos, AP5, Ciudad Nuclear, Cienfuegos, Cuba; International Atomic Energy Agency - Environment Laboratories (IAEA-EL), 4 Quai Antoine 1(er), MC-98000, Monaco.

Among natural radionuclides, Po is the major contributor to the radiation dose received by marine organisms. In cephalopods, Po is concentrated in the digestive gland, which contains over 90% of the whole-body burden of the nuclide. Although previous studies showed that Po was taken up independently of Pb, its parent nuclide, very little is known about the factors influencing its levels in cephalopods.

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There is growing evidence that poly and perfluoroalkyl substances (PFAS) exposure leads to the disruption of thyroid hormones including thyroxine (T4) and triiodothyronine (T3), and may affect telomeres, repetitive nucleotide sequences which protect chromosome ends. Many seabird species are long-lived top predators thus exhibit high contaminant levels, and PFAS-disrupting effects on their physiology have been documented especially in relation to the endocrine system in adults. On the contrary, studies on the developmental period (i.

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Diving behaviour of southern elephant seals: new models of behavioural and ecophysiological adjustments of oxygen store management.

J Exp Biol

July 2023

Centre d'Études Biologiques de Chizé-Centre National de la Recherche Scientifique (CEBC-CNRS), Equipe Prédateurs marins, UMR 7372 CNRS/Université de La Rochelle, 79360 Villiers-en-Bois, France.

Among pinnipeds, southern elephant seals (SESs, Mirounga leonina) are extreme divers that dive deeply and continuously along foraging trips to restore their body stores after fasting on land during breeding or moulting. Their replenishment of body stores influences their energy expenditure during dives and their oxygen (O2) reserves (via muscular mass), yet how they manage their O2 stores during their dives is not fully understood. In this study, 63 female SESs from Kerguelen Island were equipped with accelerometers and time-depth recorders to investigate changes in diving parameters through their foraging trips.

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Cetaceans are recognized as bioindicators of pollution in oceans. These marine mammals are final trophic chain consumers and easily accumulate pollutants. For example, metals are abundant in oceans and commonly found in the cetacean tissues.

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A keystone avian predator faces elevated energy expenditure in a warming Arctic.

Ecology

May 2023

Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 2 Rue Olympe de Gouges, FR-17000, La Rochelle, France.

Climate change is transforming bioenergetic landscapes, challenging behavioral and physiological coping mechanisms. A critical question involves whether animals can adjust behavioral patterns and energy expenditure to stabilize fitness given reconfiguration of resource bases, or whether limits to plasticity ultimately compromise energy balance. In the Arctic, rapidly warming temperatures are transforming food webs, making Arctic organisms strong models for understanding biological implications of climate change-related environmental variability.

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Climate change increases the frequency and intensity of extreme weather events that negatively impact wildlife, from individuals to whole ecosystems. In polar environments, such events include heat waves, anomalous sea ice concentrations and storms. Polar seabirds are adapted to withstand harsh conditions, and although extreme weather events affect their breeding success and other demographic rates, they are thought to affect only a part of the population.

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Global climate change is causing abiotic shifts such as higher air and ocean temperatures, and disappearing sea ice in Arctic ecosystems. These changes influence Arctic-breeding seabird foraging ecology by altering prey availability and selection, affecting individual body condition, reproductive success, and exposure to contaminants such as mercury (Hg). The cumulative effects of alterations to foraging ecology and Hg exposure may interactively alter the secretion of key reproductive hormones such as prolactin (PRL), important for parental attachment to eggs and offspring and overall reproductive success.

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Simple and rapid formic acid sample treatment for the isolation of HgSe nanoparticles from animal tissues.

Anal Chim Acta

April 2023

Departamento de Química Analítica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Madrid, 28040, Spain.

The present work explores for the first time the potential of formic acid on the extraction of tiemannite (HgSe) nanoparticles from seabird tissues, in particular giant petrels. Mercury (Hg) is considered one of the top ten chemicals of major public health concern. However, the fate and metabolic pathways of Hg in living organisms remain unknown.

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Learning is ubiquitous in animals: individuals can use their experience to fine-tune behaviour and thus to better adapt to the environment during their lifetime. Observations have accumulated that, at the collective level, groups can also use their experience to improve collective performance. Yet, despite apparent simplicity, the links between individual learning capacities and a collective's performance can be extremely complex.

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A century of mercury: Ecosystem-wide changes drive increasing contamination of a tropical seabird species in the South Atlantic Ocean.

Environ Pollut

April 2023

Littoral Environnement et Sociétés (LIENSs), UMR 7266 CNRS - La Rochelle Université, 2 Rue Olympe de Gouges, 17000, La Rochelle, France; Institut Universitaire de France (IUF), 1 Rue Descartes, 75005 Paris, France.

Mercury (Hg) is a highly toxic metal that adversely impacts human and wildlife health. The amount of Hg released globally in the environment has increased steadily since the Industrial Revolution, resulting in growing contamination in biota. Seabirds have been extensively studied to monitor Hg contamination in the world's oceans.

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Recently, has been described as a novel pathogen potentially contributing to decreased pup production in Australian fur seals (AusFS, ). Pacific gulls (PGs, ) are known to scavenge AusFS placental material during the fur seal breeding season. It is hypothesized that PGs may act as vectors for this pathogen.

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Mercury Contamination Challenges the Behavioral Response of a Keystone Species to Arctic Climate Change.

Environ Sci Technol

February 2023

Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 2 Rue Olympe de Gouges, La Rochelle FR-17000, France.

Combined effects of multiple, climate change-associated stressors are of mounting concern, especially in Arctic ecosystems. Elevated mercury (Hg) exposure in Arctic animals could affect behavioral responses to changes in foraging landscapes caused by climate change, generating interactive effects on behavior and population resilience. We investigated this hypothesis in little auks (), a keystone Arctic seabird.

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Maternal effects are thought to be essential tools for females to modulate offspring development. The selective deposition of avian maternal hormones could therefore allow females to strategically adjust the phenotype of their offspring to the environmental situation encountered. However, at the time of egg formation, several contaminants are also transferred to the egg, including per- and polyfluoroalkyl substances (PFAS) which are ubiquitous organic contaminants with endocrine disrupting properties.

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Animals have to develop novel behaviours to adapt to anthropogenic activities or environmental changes. Fishing vessels constitute a recent feature that attracts albatrosses in large numbers. While they provide a valuable food source through offal and bait, they cause mortalities through bycatch, such that selection on vessel attraction will depend on the cost-benefit balance.

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During extreme climate events, behavioural thermoregulation may buffer ectotherms from thermal stress and overheating. However, heatwaves are also combined with dry spells and limited water availability, and how much individuals can behaviourally mitigate dehydration risks through microclimate selection remains largely unknown. Herein, we investigated the behavioural and physiological responses to changes in air and microhabitat humidity in a terrestrial ectotherm, the asp viper (Vipera aspis).

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Many animals migrate after reproduction to respond to seasonal environmental changes. Environmental conditions experienced on non-breeding sites can have carryover effects on fitness. Exposure to harmful chemicals can vary widely between breeding and non-breeding grounds, but its carryover effects are poorly studied.

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