Browsing by Autor "Marc Pouilly"

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Changes of taxonomic and trophic structure of fish assemblages along an environmental gradient in the Upper Beni watershed (Bolivia)
(Wiley, 2006) Marc Pouilly; Silvia Eugenia Barrera Berdugo; Claudio Rosales
The distribution and the diet of 28 fish species were evaluated, during the dry season, in 12 streams of the Upper Beni watershed (Amazon basin, Bolivia). The 12 streams were of similar size (stream width and water depth) but situated on a gradient of altitude in the Andean and sub‐Andean areas. The environmental conditions in the stream changed in relation to the altitude. As altitude decreased, slope and water velocity also decreased, while temperature, conductivity, pH and the proportion of pools increased. Although the diets of the species were mainly based on two aquatic autochthonous food resources, invertebrates and sediment, species were classified into five trophic guilds: detritivores, algivores, piscivores, invertivores‐omnivores and aquatic specialist invertivores. In all streams invertivores dominated or co‐dominated with detritivores. The trophic structure of the assemblages, however, changed in relation to the environmental gradient. The fish species richness increased and the trophic composition became more diverse at lower altitudes, when slope decreased and temperature increased. At the same time, the relative number of invertivore species decreased, whereas the relative number of detritivore, algivore and piscivore species increased. Decreasing altitude appeared to play a role similar to increasing stream size along the longitudinal gradient. This could be explained by geomorphological and temperature variations that may generate environmental conditions favourable to an increase of productivity.
Commercial traceability of Arapaima spp. fisheries in the AmazonBasin: can biogeochemical tags be useful?
(2018) Luciana Alves Pereira; Roberto Ventura Santos; Marília Hauser; Fabrice Duponchelle; Fernando Carvajal; Christophe Pécheyran; Sylvain Bérail; Marc Pouilly
Abstract. The development of analytical tools to determine the origin of fish is useful to better understand patterns of habitat use and to monitor, manage and control fisheries, including certification of food origin. The application of isotopic procedures to study fish calcified structures (scales, vertebrae, and otoliths) may provide robust information about the fish geographic origin and environmental living conditions. In this study, we used Sr and C isotopic markers recorded in otoliths of wild and farmed commercialized pirarucu (Arapaima spp.) to evaluate their prediction potential to trace the fish origin. Wild and farm fish specimens, as well as food used for feeding pirarucu in captivity, were collected from different sites. Isotope analyses of otoliths performed by IRMS (δ13C) and LAfs-MC-ICPMS (87Sr/86Sr) were compared to the isotopic composition of water and of the food given to the fish in the farms. Wild fish specimens that lived in environments with the largest fluctuation of river water Sr isotope ratios over time presented the largest Sr isotope variations in otoliths. A quadratic discriminant analysis on otolith isotopic composition provided 58 % of correct classification for fish production (wild and farmed) and 76 % of correct classification for the fish region. Classification accuracy for region varied between 100 % and 29 % for the Madeira and the lower Amazon fishes, respectively. Overall, this preliminary trial is not yet fully satisfying to be applied as a commercial traceability tool. However, given the importance of Arapaima spp. for food security and the generation of economic resources for millions of people in the Amazon basin, further analyses are needed to increase the discrimination performance of these biogeographical tags.
Commercial traceability of Arapaima spp. fisheries in the Amazon basin: can biogeochemical tags be useful?
(Copernicus Publications, 2019) Luciana Alves Pereira; Roberto Ventura Santos; Marília Hauser; Fabrice Duponchelle; Fernando Carvajal-Ramírez; Christophe Pécheyran; Sylvain Bérail; Marc Pouilly
Abstract. The development of analytical tools to determine the origin of fishes is useful to better understand patterns of habitat use and to monitor, manage, and control fisheries, including certification of food origin. The application of isotopic analyses to study calcified structures of fishes (scales, vertebrae, and otoliths) may provide robust information about the fish geographic origin and environmental living conditions. In this study, we used Sr and C isotopic markers recorded in otoliths of wild and farmed commercialized pirarucu (Arapaima spp.) to evaluate their prediction potential to trace the fishes origin. Wild and farmed fish specimens, as well as food used for feeding pirarucu in captivity, were collected from different sites. Isotope composition of otoliths performed by isotope-ratio mass spectrometry (IRMS; δ13C) and femtosecond laser ablation multi-collector inductively coupled plasma mass spectrometry (LAfs-MC-ICPMS; 87Sr∕86Sr) were compared to the isotopic composition of water and of the food given to the fishes in the farms. Wild fish specimens that lived in environments with the largest fluctuation of river water Sr isotope ratios over time presented the largest Sr isotope variations in otoliths. A quadratic discriminant analysis on otolith isotopic composition provided 58 % of correct classification for fish production (wild and farmed) and 76 % of correct classification for the fish region. Classification accuracy for region varied between 100 % and 29 % for the Madeira and the Lower Amazon fishes, respectively. Overall, this preliminary trial is not yet fully developed to be applied as a commercial traceability tool. However, given the importance of Arapaima spp. for food security and the generation of economic resources for millions of people in the Amazon basin, further analyses are needed to increase the discrimination performance of these biogeographical tags.
Delimiting species by reproductive isolation: the genetic structure of epigean and hypogean Trichomycterus spp. (Teleostei, Siluriformes) in the restricted area of Torotoro (Upper Amazon, Bolivia)
(Springer Science+Business Media, 2007) Jean‐François Renno; Claude Gazel; Guido Miranda; Marc Pouilly; Patrick Berrebi
Dietary patterns and sympatry in Lake Titicaca (Bolivia): the role of seasonality in niche overlap between native Andean killifish
(Springer Science+Business Media, 2025) Erick Loayza; Arturo Muñoz‐Saravia; Julio Pinto; Carla Ibañez; Marc Pouilly; Geert Janssens
Dietary–morphological relationships in a fish assemblage of the Bolivian Amazonian floodplain
(Wiley, 2003) Marc Pouilly; Faviany Lino; J.‐G. Bretenoux; Claudio Rosales
Morphological correlates of diet were examined in 48 species of freshwater fishes from floodplain lakes in the central part of the Mamoré River (Bolivian Amazon). The species were classified, according to the percentage occurrence of seven food items, into eight broad trophic categories: mud feeders, algivores, herbivores, terrestrial invertivores and omnivores, carnivores, zooplanktivores, aquatic invertivores and piscivores. There were significant relationships between the diet and morphology of the fishes even when the effect of taxonomical relatedness between species was eliminated. Relative gut length was the main morphological variable used to order species on a carnivore to mud feeder gradient. Standard length and head and mouth size were the morphological variables most closely associated with prey size. Mud feeder, algivore and piscivore species appeared as the most dietary and morphologically specialized. These results support both the hypotheses that species morphology influences the diet and that morphological similarity is conserved even in comparison with taxonomically unrelated species.
Dietary-morphological relationships in fish assemblages of small forested streams in the Bolivian Amazon
(EDP Sciences, 2007) Carla Ibañez; Pablo A. Tedesco; Rémy Bigorne; Bernard Hugueny; Marc Pouilly; Claudia Zepita; José Zubieta; Thierry Oberdorff
We explored the relationships between diet and morphology in 30 fish species from forested tropical streams of the Bolivian Amazon. These species were first assigned to eight broad trophic guilds based on stomach contents analysis. The relationships between diet and morphology were then examined using Redundancy Analysis, after having checked for potential phylogenetical effects. Results show that, independently of any phylogenetic constraints, some of the trophic guilds could be grossly predicted from few relevant morphological attributes (i.e. relative intestinal length, standard length and mouth orientation) and thus suggest a significant link between diet and morphology. In other words, species having similar diet tend to converge to some extent on some morphological attributes. This link was nevertheless rather weak, suggesting that even if morphology may set limits to patterns of resource use, these limits are broad enough to allow fishes changing their choice of prey resources to respond to local biotic and/or abiotic conditions.
Effect of water quality on growth of four fish species in the Iténez basin (Upper Madera, Amazon)
(Springer Science+Business Media, 2012) Esther López Siangas; Marc Pouilly; Adamit Vallejos; Tamara Pérez; Danny Rejas
Fish habitat preferences in large streams of southern France
(Wiley, 1999) Nicolas Lamouroux; Hervé Capra; Marc Pouilly; Yves Souchon
1. Relationships between fish and their habitat over whole geographic regions, which are evident from studies of many streams and species, can improve understanding of lotic communities and provide reliable management tools. Nevertheless, most habitat preference studies have been based on single sites, and confined to small streams and to game species. 2. Regional habitat preference models, based on local velocity, depth and roughness, were developed for twenty‐four species and their size classes commonly found in large European streams. Fish surveys were conducted in six large streams in southern France over an 8‐year period. To limit the influences of habitat variables other than those studied, we estimated fish preferences within each survey and averaged this information across surveys. Preferences were fitted with confidence intervals and their sensitivity to field uncertainty was evaluated. 3. Most species and size classes had significant preferences for local habitat conditions which were consistent across the region. Habitat preferences predominant in the region overall were not always observed at any one site, but habitat conditions preferred on average in the region were never actually avoided locally. These results support the use of regional preference models for fish and the development of similar models for other lotic groups whose sensitivity to local habitat conditions has been reported elsewhere.
Fish-AMAZBOL: a database on freshwater fishes of the Bolivian Amazon
(Springer Science+Business Media, 2014) Fernando M. Carvajal‐Vallejos; Rémy Bigorne; América J. Zeballos Fernández; Jaime Sarmiento; Soraya Barrera; Takayuki Yunoki; Marc Pouilly; José Zubieta; Evans De La Barra; Michel Jégu
FUNCIONAMIENTO ECOLOGICO DE LAS LAGUNAS DE LA ZONA DE INUNDACIÓN DEL RIO MAMORÉ, (BENI-BOllVIA)
(1999) Marc Pouilly; Caria Ibañez; M.E Alcedo Gutiérrez; Takayuki Yunoki
ECOLOGICAL FUNCTIONING OF FLOODPLAIN LAKES OF MAMORE RIVER (BENI -BOLIVIA) El sistema del rio Mamore en la region de Trinidad, esta constituido por el lecho principal y por lagunas anexas, antiguos cauces. Estas son diferentes debido a su edad, morfologia, conexion y distancia al Mamore. El objetivo del presente estudio es el de comprobar la hipotesis que la zona de inundacion tiene una estructura espacial y temporal en cuanto a la distribucion de los organismos acuaticos (fitoplancton; zooplancton; peces). Ocho lagunas correspondiendo a un gradiente de distancia al rio Mamore, fueron muestreadas durante los dos meses extremos del ciclo hidrologico (marzo y octubre 1998). Las seis primeras lagunas se encuentran dentro del bosque galeria, sometidas a inundaciones anuales: dos estan cerca del lecho principal, dos al medio del bosque y dos en el limite entre el bosque y la sabana. Las dos ultimas se ubican en la sabana y desconectadas del sistema Mamore. La composicion cuantitativa de las tres comunidades de fitoplancton (59 generos), zooplancton (34 generos) y peces (92 generos) esta presentada para cada laguna y para las dos epocas. Los resultados evidencian una diferencia de composicion y de densidad entre las epocas, con mayor densidad y riqueza en epoca de estiaje. Al nivel espacial se observa, patrones de composicion que varian segun las comunidades. Palabra-Claves: Amazonia Boliviana, Zona de inundacion, Fitoplancton, Zooplancton, Peces. ABSTRACT Mamore river system is constituted by a main channel and lateral oxbow lakes. These annexes are different in age, morphology, connection and distance to the river. The aim of the study is to check the hypothesis that the floodplain aquatic units have a spatial and a temporal structure as regarding biological communities of phytoplankton, zooplankton and fish. Eight lakes situated on a distance gradient from the Mamore river were sampled in the two extreme months of the hydrological cycle (March and October 1998). Six oxbows lakes lie in the gallery forest and are under annual flood influence: Two are situated clase to the rivet; two in the middle of the forest and two at the limit between forest and savannah. The two ultimate lakes correspond to savannah fIar lakes which are generally disconnected from the Mamore system. The composition of the biological communities of phytoplankton (59 genus), zooplankton (34 genus) and fishes (92 genus) are presented for each oxbows or lakes and for the two sampling dates. Results showed differences in the composition and the density between dates with greater density and richness during the low water season. The spatial pattern is also different between the 8 lakes and different for each community. Keywords: Bolivian Amazonia, Floodplain, Phytoplankton, Zooplankton, Fish community.
Stiphodon melen. sp., a new species of Freshwater goby from Vanuatu and New Caledonia (Teleostei, Gobiidae, Sicydiinae), and comments about amphidromy and regional dispersion
(Muséum national d'histoire naturelle, 2009) Philippe Keith; Gérard Marquet; Marc Pouilly
Keith P., Marquet G. & Pouilly M. 2009. — Stiphodon mele n. sp., a new species of Freshwater goby from Vanuatu and New Caledonia (Teleostei, Gobiidae, Sicydiinae), and comments about amphidromy and regional dispersion. Zoosystema 31 (3): 471-483.Stiphodon mele n. sp. is described on the basis of material collected from Vanuatu and New Caledonia. It is distinguished from all other congeners in having 9 segmented rays in the second dorsal fin, usually 13 pectoral rays, 36–41 fine tricuspid premaxillary teeth, 2 small symphyseal teeth in female vs. 2–4 stout teeth in males, predorsal scales absent, and low number of scales in transverse back (3–7) and lateral series (14–21). This new species spawns in freshwater, the free embryos drift downstream to the sea where they undergo a planktonic phase, before returning to the rivers to grow and reproduce: it is an amphidromous species. As many other Sicydiinae, Stiphodon mele n. sp., is endemic to Vanuatu and New Caledonia. Numerous factors occur to control the dispersion of the amphidromous species. It is necessary to consider all of these factors to explain the existence of many endemic species and the broad or small distribution of the species in the Indo-Pacific area. The management and the conservation of Stiphodon mele n. sp. have to be necessarily regional.
Mercury bioaccumulation patterns in fish from the Iténez river basin, Bolivian Amazon
(Elsevier BV, 2012) Marc Pouilly; Tamara Pérez; Danny Rejas; F. Monroy Guzman; Giovanni Crespo; Jean‐Louis Duprey; Jean-Remy D. Guimarães
Morphology and reproduction of the cavefish Trichomycterus chaberti and the related epigean Trichomycterus cf. barbouri
(Wiley, 2003) Marc Pouilly; Guido Miranda
Hypogean and epigean populations of Trichomycterus catfishes inhabit streams from different environments (cave, headwater, canyon and valley) in the Torotoro National Park in the Andes, Bolivia. A significant reduction in the diameter of the eyes and in the surface area of the mesencephalon was observed in subterranean populations, along with an increase in the surface area of the telencephalon. Contrary to expectations, the barbel did not appear to be longer in hypogean populations. The observed pattern of modification of the other variables (pigmentation, eye asymmetry, surface area of the cerebellum and rhombencephalon, fecundity and egg diameter) corresponded to a gradient of values from valley to canyon, headwater and subterranean populations. This result argues not for a simple distinction between epigean and hypogean populations but for an adaptation to an environmental gradient of constraints in which caves correspond to an extreme situation.
Particulate Mercury and Particulate Organic Matter in the Itenez Basin (Bolivia)
(Multidisciplinary Digital Publishing Institute, 2020) Fabiola Guzmán-Uria; Isabel Morales-Belpaire; Darío Achá; Marc Pouilly
In rivers and other freshwater bodies, the presence of mercury can be due to direct contamination by anthropic activities such as gold mining. However, it can also be attributed to atmospheric deposition and erosion, runoff, or lixiviation from surrounding soils. In the case of the Amazon rainforest, high mercury contents have been reported for litter and topsoil, which could affect the mercury concentrations in water bodies. Samples of suspended particulate matter were obtained from a transect of the Itenez River, associated lakes, and some of its tributaries. The aim was to obtain information on particulate mercury’s origin in the study area and determine the relationship between particulate mercury and particulate organic carbon. The concentration of mercury, organic matter, and the C:N ratio of the suspended matter was determined. The concentration of particulate mercury by water volume depended on changes in suspended matter loads, which in turn were mostly affected by the nature of the watershed or sediment resuspension. The observed values for the percentage of organic matter and the C:N ratio suggest that most of the mercury content in rivers and lakes originated from soils. A positive correlation was found between mercury concentration by weight of particulate matter and organic carbon content in particles. This correlation might be due to the direct binding of mercury to organic matter through functional groups like thiols or to an indirect effect of oxyhydroxides that can adsorb mercury and are associated with organic matter.
Predicting habitat suitability for lotic fish: linking statistical hydraulic models with multivariate habitat use models
(Wiley, 1998) Nicolas Lamouroux; Hervé Capra; Marc Pouilly
Quantitative estimates of habitat suitability in a stream reach generally result from coupling a hydraulic habitat model with a biological model of habitat use. The choice of each of these models has led to much controversy and discussion. Nevertheless, most habitat studies of lotic fish use a deterministic hydraulic model and univariate suitability curves. The objective of this contribution is to present a new, alternative method, which relates statistical hydraulic models to multivariate habitat use models. Our statistical hydraulic models predict the frequency distributions of hydraulic variables such as velocity or water depth within stream reaches. Their main advantage is the simplicity of their input variables (mainly discharge and average characteristics of the reach). Our multivariate formulation of habitat use models takes into account the local variability of fish habitat, predicting habitat suitability as a function of the frequency distribution of hydraulic variables within the local fish habitat. We demonstrate how these two model types can be linked to estimate habitat suitability in a stream reach as a function of discharge, focusing on two fish species (barbel, chub) in a regulated reach of the French Rhône River. The main limitations of this new method are a result of mathematical constraints associated with the linkage of the two modelling approaches and to uncertainties in transferring biological models from one stream to another because of insufficient data. Despite these limitations, the method provides solutions to several critical problems facing existing approaches and the simplicity of its input variables can accelerate the validation process of habitat models. Therefore, our first simulations strongly encourage: (i) the use of statistical approaches to describe hydraulic variables; and (ii) the study of multivariate habitat use models that apply to a large variety of streams. © 1998 John Wiley & Sons, Ltd.
Predicting habitat suitability for lotic fish: linking statistical hydraulic models with multivariate habitat use models
(Wiley, 1998) Nicolas Lamouroux; Hervé Capra; Marc Pouilly
Quantitative estimates of habitat suitability in a stream reach generally result from coupling a hydraulic habitat model with a biological model of habitat use. The choice of each of these models has led to much controversy and discussion. Nevertheless, most habitat studies of lotic fish use a deterministic hydraulic model and univariate suitability curves. The objective of this contribution is to present a new, alternative method, which relates statistical hydraulic models to multivariate habitat use models. Our statistical hydraulic models predict the frequency distributions of hydraulic variables such as velocity or water depth within stream reaches. Their main advantage is the simplicity of their input variables (mainly discharge and average characteristics of the reach). Our multivariate formulation of habitat use models takes into account the local variability of fish habitat, predicting habitat suitability as a function of the frequency distribution of hydraulic variables within the local fish habitat. We demonstrate how these two model types can be linked to estimate habitat suitability in a stream reach as a function of discharge, focusing on two fish species (barbel, chub) in a regulated reach of the French Rhône River. The main limitations of this new method are a result of mathematical constraints associated with the linkage of the two modelling approaches and to uncertainties in transferring biological models from one stream to another because of insufficient data. Despite these limitations, the method provides solutions to several critical problems facing existing approaches and the simplicity of its input variables can accelerate the validation process of habitat models. Therefore, our first simulations strongly encourage: (i) the use of statistical approaches to describe hydraulic variables; and (ii) the study of multivariate habitat use models that apply to a large variety of streams. © 1998 John Wiley & Sons, Ltd.
Revealing capture sites and movements by strontium isotope analyses in bones of Caiman yacare in the Beni river floodplain, Bolivia
(2021) Marc Pouilly; Sergio Gómez; Christophe Pécheyran; Sylvain Bérail; Gustavo Álvarez; Guido Miranda
ABSTRACT Studying the distribution of organisms and their movements is fundamental to understand population dynamics. Most studies indicated that crocodilians do not move around much but several studies demonstrated that some species showed movement patterns. Detection of these movements along the individual life is still a challenge. In this study we analyzed the variation of strontium isotopic ratio ( 87 Sr /86 Sr) in the femur bones of 70 Caimanya care individuals caught in 16 sites located in five hydrological sectors of the Beni river floodplain in Bolivia. Our results demonstrated for the first time that such a methodology could yield indications about the capture sites and reconstruct individual life history. Analyses of the outer part of the femur of 70 individuals showed that capture sites could be differentiated between sectors and even between sites or groups of sites in each sector. Studies of complete 87 Sr /86 Sr profiles along the femur, representing the individual’s entire life, were performed on 33 yacares. We found that most of the individuals did not show any significant isotopic variation throughout their lives. This absence of variation could result from a high fidelity to the birth site, and/or from an insignificant isotopic variation between the water bodies through which the animal has potentially moved. However, 24% of the analyzed individuals presented significant variations that can be considered as movements between different habitats. Based on the observed low proportion of moving yacares, we advocated that each water body should be considered an individual management unit.
Strontium isotope analyses in femur bones of Caiman yacare from the Beni river floodplain (Bolivia)
(European Organization for Nuclear Research, 2021) Marc Pouilly; GOMEZ Sergio; Christophe Pécheyran; Sylvain Bérail; ALVEREZ Gustavo; Guido Miranda
Excel file of data used in Pouilly M. , Gomez S., Pécheryan C., Bérail S., Alvarez G. and Miranda-Chumacero. 2021. Revealing capture sites and movements by strontium isotope analyses in bones of Caiman yacare in the Beni river floodplain, Bolivia. BioRxiv Preprint, https://doi.org/10.1101/2021.04.14.439857 Complete profiles of 87Sr/86Sr were performed from the core to the external border of the femur bone of 33 yacares. Sr isotope ratio (87Sr/86Sr) profile of variation was obtained by a continuous analysis (LA - MC - ICPMS) on a transect perpendicular to growth marks running from the femur center (corresponding to the beginning of life) to the bone external border (corresponding to the capture period). First line of the table indicate sample name (detailled in the 'cod' sheet) First column corresponds to the distance form the center of the bone (in micrometer) Following columns correspond to the 87Sr/86Sr profil (one value by distance) for each sample (yacare individual)
Strontium isotope analyses in femur bones of Caiman yacare from the Beni river floodplain (Bolivia)
(European Organization for Nuclear Research, 2021) Marc Pouilly; GOMEZ Sergio; Christophe Pécheyran; Sylvain Bérail; ALVEREZ Gustavo; Guido Miranda
Excel file of data used in Pouilly M. , Gomez S., Pécheryan C., Bérail S., Alvarez G. and Miranda-Chumacero. 2021. Revealing capture sites and movements by strontium isotope analyses in bones of Caiman yacare in the Beni river floodplain, Bolivia. BioRxiv Preprint, https://doi.org/10.1101/2021.04.14.439857 Complete profiles of 87Sr/86Sr were performed from the core to the external border of the femur bone of 33 yacares. Sr isotope ratio (87Sr/86Sr) profile of variation was obtained by a continuous analysis (LA - MC - ICPMS) on a transect perpendicular to growth marks running from the femur center (corresponding to the beginning of life) to the bone external border (corresponding to the capture period). First line of the table indicate sample name (detailled in the 'cod' sheet) First column corresponds to the distance form the center of the bone (in micrometer) Following columns correspond to the 87Sr/86Sr profil (one value by distance) for each sample (yacare individual)