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We studied how changing human impacts affected phytoplankton dynamics in the freshwater and brackish tidal reaches of the Zeeschelde estuary (Belgium) between 2002 and 2018. Until the early 2000s, the Zeeschelde was heavily polluted due to high wastewater discharges. By 2008, water quality had improved, resulting in lower nutrient concentrations and higher oxygen levels. Since 2009, however, increased dredging activities resulted in altered hydro-dynamics and increased suspended sediment concentration. The combined effects of these environmental changes were reflected in three marked transitions in phytoplankton community composition. Assemblages were dominated by Thalassiosirales and green algae (especially Scenedesmaceae) until 2003. The period 2003-2011 was characterized by the wax and wane of the centric diatoms Actinocyclus and Aulacoseira, while in the period 2012-2018 Thalassiosirales and Cyanobacteria became dominant, the latter mainly imported from the tributaries. Phytoplankton biomass increased sharply in 2003, after which there was a gradual decline until 2018. By 2018, the timing of the growing season had advanced with about one month compared to the start of the study, probably as a consequence of climate warming and intensified zooplankton grazing pressure. Our study shows that de-eutrophication (during the 2000s) and morphological interventions in the estuary (in the 2010s) were dominant drivers of phytoplankton dy-namics but that the main shifts in community composition were triggered by extreme weather events, suggesting sig-nificant resistance of autochthonous communities to gradual changes in the environment.

The dragonfly Leucorrhinia pectoralis was recorded in Slovakia at 38 sites in 112 findings and there were 707 imagoes. Reproduction was confirmed in seven sites by finding of 35 larvae and exuviae. The highest number of sites with the occurrence of L. pectoralis is located in the Záhorská nížina lowland; most sites in Slovakia are located at an altitude of 213–351 m. L. pectoralis was recorded together with 49 species of dragonflies, and the average number of L. pectoralis was 9.56 individuals per site. It occurs in the communities as a dominant species (9.5%) together with eudominants Coenagrion puella, C. hastulatum and Libellula quadrimaculata. By non-metric multidimensional scaling (NMDS), we found a coenotic correlation to peat species Libellula quadrimaculata, Leucorrhinia rubicunda, L. dubia and Sympetrum danae. By redundancy linear analysis (RDA), we found a Monte Carlo permutation test to make a non-random contribution to the explained variability of seven factors (p = 0.012–0.034). L. pectoralis statistically significantly prefers habitats in the forest landscape (r = 0.62, p = 0.0063), the presence of vegetation (r = 0.94, p = 0.0003) and peatbogs (r = 0.61, p = 0.0058). We did not confirm a significant correlation to altitude. Based on easy determination, territoriality (especially males) and bioindicative sensitivity of larvae, L. pectoralis is accepted as an umbrella species. L. pectoralis has a high dispersion potential and is suitable for creating the meta-population character of local populations, which is important for the conservation management of the species.

The surge of oil palm production in the Neotropics has become a major concern about the potential impacts on biodiversity. In the Colombian Orinoquia, which has shown a massive landscape transformation due to the growth of oil palm plantations, the effects of oil palm agriculture on bats in this region have not been studied up to date. To understand the impact of habitat conversion on bat diversity, we characterised bat assemblages in secondary forest and palm plantations in the Colombian Piedmont foothills (Meta, Colombia). We captured 393 individuals (forest = 81, plantation = 312) of 18 species and three families. The forest cover presented three exclusive species while the plantation had five. Species diversity (q1) and evenness (J’) were higher in the forest compared to the plantation. These differences derived from the increase in abundances of generalist species (Artibeus sp., Carollia spp.) in the plantation. Despite the habitat simplification caused by oil palm plantations, this monoculture provides a cover that is used by some bats, decreasing their risk of predation and allowing movement between patches of forest habitat as stepping-stones. Maintaining forest cover in agricultural landscapes favours diversity by generating a “spillover effect” of the forest towards plantations, which in the case of some bats contributes to the reduction of species isolation and the maintenance of ecosystem services provided by them. It is important to improve management practices of oil palm plantations to minimise negative impacts on biodiversity, considering the expansion of this productive system and the scarcity of protected areas in this region.

Peat bogs of Europe are ecosystems with very specific extremely environmental conditions. Among peat bog water bodies are lakes, streams and hollows, which are characterized by strongly acidic and mineral poor water. However, the diversity of the inhabitants of the peat water environment is very poorly investigated. The aim of this study was to examine the water beetle diversity and species composition in the peat bog of Belarus. In total, 45 species of water beetles belonging to 3 families (Gyrinidae, Dytiscidae, Hydrophilidae) were sampled by entomological net. Among them specialised tyrphophilous species were Hydroporus erythrocephalus, H. incognitus, H. melanarius, H. obscurus, H. tristis, Ilybius aenescens, Rhantus sututellus, Enochrus affinis, E. ochropterus. A rather high diversity was recorded (Shannon index H’= 2.037–2.912). The highest diversity for water beetles was in lakes.

Resumen Introducción: Los arroyos asociados a bofedales se hallan en ambientes donde las condiciones son extremas con temperaturas muy variables, baja presión atmosférica e intensa radiación solar. Sin embargo, existen ensamblajes de macroinvertebrados asociados a estos ambientes, cuya información es escasa. A escala global y regional, las características de los macroinvertebrados cambian con el aumento de la latitud y altitud (disminución de la riqueza y variación de la composición). A nivel local, también se puede agregar el efecto de las aguas ácidas y de elevada conductividad proveniente de manantiales que se unen a los arroyos, que generan heterogeneidad en la calidad de agua y consecuentemente en las características de los macroinvertebrados. Objetivo: Comparar la diversidad, composición y abundancia de macroinvertebrados y las características fisicoquímicas del agua de arroyos asociados a dos bofedales altoandinos, ubicados en el departamento de Ayacucho, Perú. Metodología: Se estudiaron once estaciones ubicados en arroyos de dos bofedales: 7 en Guitarrachayocc (G) de 43 ha (n = 28) y 4 en Pichccahuasi (P) de 28 ha (n = 8). Se empleó una red de Surber (0.3 mm de malla, área de muestreo de 1 200 cm2), para realizar muestreos mensuales de octubre de 2016 a abril de 2017. Análisis de componentes principales (PCA) y análisis de varianza multivariante no paramétrico (NP-MANOVA) se aplicaron para comparar las características del agua. Además, se utilizó un análisis de coordenadas principales (PCoA) y NP-MANOVA para comparar el ensamblaje. La prueba no paramétrica de Kruskal-Wallis (α = 0.05) se utilizó para comparar las abundancias absolutas de los taxa principales. Resultados: Las características del agua fueron heterogéneas, con pH de 3.2 (± 0.4) a 7.6 (± 0.1), conductividad de 168.9 (± 91) µS/cm a 1 117 (± 159.3) µS/cm; diferencias que fueron significativas (p < 0.05) al comparar las estaciones de muestreo, donde el agua de G6 presenta los mínimos valores de pH y los máximos de conductividad, al igual que cloruros. Se recolectaron un total de 8 126 individuos, distribuidos en 26 taxa de 20 familias, 11 órdenes y cinco clases. Los insectos fueron el grupo más diverso y abundante. A pesar a la cercanía de los arroyos de los bofedales, presentaron diferencias: en G, se registró 25 taxa, con dominancia de Macrelmis sp., Dicrotendipes sp., Claudioperla sp., Meridialaris sp. y en P, 9, con dominancia de Pedrowygomya sp., Hyalella sp. y Dicrotendipes sp. La densidad fue de 475 ind./m2 y de 31 ind./m2 para el bofedal G y P respectivamente, estos valores fueron estadísticamente diferentes (p < 0.05). El PCoA y el PCA confirmados por NP-MANOVA mostraron que G6 es diferente (p < 0.05) dentro de G porque recibe el aporte de agua de un manantial. Conclusiones: La riqueza, composición y densidad de los macroinvertebrados son diferentes en los arroyos según el bofedal al cual se halla asociado. La contribución de los manantiales a los arroyos genera cambios drásticos en la calidad del agua y los macroinvertebrados, determinando la formación de ensamblajes con diferente riqueza y estructura. Abstract Introduction: Streams associated with high Andean wetlands are found in environments where conditions are extreme, highly variable temperature, low atmospheric pressure, intense solar radiation. The macroinvertebrate assemblages have been poorly studied compared to streams located at lower altitudes. On a global and regional scale, the characteristics of macroinvertebrates change with the increase in latitude and altitude (decreasing in richness and variation in composition). At the local level, the effect of acidic waters with high conductivity from springs that join streams generate heterogeneity in water quality and consequently in the characteristics of macroinvertebrate structure. Objective: To compare the diversity, composition and abundance of macroinvertebrates and the physicochemical characteristics of stream water in two high Andean wetlands in Peru. Methodology: Eleven stations located in streams of two high Andean wetlands were studied: 7 in Guitarrachayocc (G) of 43 ha (n = 28) and 4 in Pichccahuasi (P) of 28 ha (n = 8). A Surber sampler (0.3 mm mesh, sampling area of 1 200 cm2) was used to carry out monthly samplings from October 2016 to April 2017. Principal Component Analysis (PCA) and Non-Parametric-Multivariate-Analysis-Of-Variance (NP-MANOVA) were applied to compare water characteristics. The macroinvertebrate assemblages from the two streams were compared by using a Principal coordinate analysis (PCoA), NP-MANOVA, and a non-parametric Kruskal-Wallis test (α = 0.05). Results: The characteristics of the water were heterogeneous, with significant differences in pH which ranged from 3.2 (± 0.4) to 7.6 (± 0.1) and conductivity ranging from 168.9 (± 91.0) µS / cm to 1 117.0 (± 159.3) µS / cm. In particular, G6 presented the lowest pH values and the highest electrical conductivity, as well as chlorides. A total of 8 126 individuals were collected, distributed in 26 taxa from 20 families, 11 orders and five classes. Insects were the most diverse and abundant group. Differences were found between the streams of the highland wetlands, despite their proximity: in G, 25 taxa were registered, with a dominance of Macrelmis sp., Dicrotendipes sp., Claudioperla sp. and Meridialaris sp. and in P, 9, with a dominance of Pedrowygomya sp., Hyalella sp. and Dicrotendipes sp. The density was 475 ind./m2 and 31 ind./m2 for G and P respectively, these values were statistically different (p < 0.05). The PCoA and PCA confirmed by NP-MANOVA showed that G6 was different (p < 0.05) within G because it receives water contribution from a spring. Conclusions: The richness, composition and density of macroinvertebrates were different in streams depending on the bofedal with which it is associated. The contribution of the springs to the streams generates drastic changes in the quality of the water and the macroinvertebrates, determining the formation of assemblages with different richness and structure.

The structure of the cumacean assemblages from the southern margin of the Cap Ferret Canyon was studied at 13 stations ranging from 346 to 1099 m depth with a modified Macer-GIROQ suprabenthic sledge (four superimposed nets; 0.5 mm mesh size). A total of 1885 specimens were collected and classified into 5 families and 42 species. The total abundances fluctuated between 2.8 ind./100 m2 (station TS04; 484-485 m) and 55.8 ind./100 m2 (station TS08; 714-708 m). The highest values of species richness and diversity were recorded at station TS13 (1097-1099 m): S=25 species; H’(log2)=4.05. The near-bottom vertical distribution of the cumacean fauna showed the same pattern at all stations: at least 60% of the individu­als were sampled by the lower net of the sledge and a drastic abundance decrease occurred between the two lowermost water layers sampled by the sledge. The multivariate analysis carried out on abundance data discriminated three main groups of stations distributed across depth (TS09 excluded): group Ia (346-485 m) characterized by the dominance of Nannastacidae (57.2%) at family level and Campylaspis sulcata, Leptostylis macrura at species level; group Ib (522-714 m) characterized by the dominance of Nannastacidae (66.1%) at family level and Campylaspis squamifera, C. laevigata and Leptostylis ma­crura at species level; and group II (790-1099 m) characterized by the dominance of Diastylidae (40.3%) at family level and Makrokylindrus (Adiastylis) josephinae, Leucon (Epileucon) pusillus and Diastyloides serratus at species level. According to this analysis, the main faunal change occurs between group I and II between 714 and 790 m, in relation to changes in the texture of surficial sediments. Although bathyal cumacean assemblages appear to be less abundant than those studied on continental shelves, they are significantly more diverse. However, such results could be in part related to the use of different sampling methods., Se ha estudiado la estructura de las comunidades de cumáceos del margen sur del cañón de Cap Ferret en 13 estaciones, distribuídas desde los 346 hasta los 1099 m de profundidad con un patín suprabentónico Macer-GIROQ modificado (cuatro redes superpuestas; 0.5 mm de malla). En total, se recolectaron 1885 especímenes que fueron clasificados en cinco familias y 42 especies. La densidad total varió entre 2.8 ind./100 m2 (estación TS04; 484-485 m) y 55.8 ind./100 m2 (estación TS08; 714-708 m). Los valores máximos de riqueza específica y diversidad se obtuvieron en la estación TS13 (1097-1099 m): S=25 especies; H’(log2)=4.05. La distribución vertical cercana al fondo de la fauna de cumáceos mostró el mismo patrón en las diferentes estaciones: al menos el 60% de los individuos fue muestreado en la red inferior del patín y se observó un descenso drástico de la abundancia entre las dos capas de agua inferiores muestreadas por el patín. El análisis multivariante llevado a cabo con los datos de densidad discrimina tres grupos principales de estaciones (excluida TS09) distribuidos según la profundidad: el grupo Ia (346-485 m) caracterizado por la dominancia de los Nannastacidae (57.2%) a nivel de familia, y por Campylaspis sulcata y Leptostylis macrura a nivel de especie; el grupo Ib (522-714 m) caracterizado también por la dominancia de los Nannastacidae (66.1%) a nivel de familia, pero por Campylaspis squamifera, C. laevigata y Leptostylis macrura a nivel de especie; el grupo II (790-1099 m) caracterizado por la dominancia de los Diastylidae (40.3%) a nivel de familia, y por Makrokylindrus (Adiastylis) josephinae, Leucon (Epileucon) pusillus y Diastyloides serratus a nivel de especie. De acuerdo con este análisis, el principal cambio faunístico ocurre entre los grupos I y II entre 714 y 790 m, relacionado con cambios en la textura de los sedimentos superficiales. Aunque las comunidades de cumáceos batiales parecen ser menos densas que las estudiadas en la plataforma continental, son significativamente más diversas. No obstante, estos resultados podrían estar en parte relacionados con el uso de métodos de muestreo diferentes.

Background Giant clams and scleractinian (reef-building) corals are keystone species of coral reef ecosystems. The basis of their ecological success is a complex and fine-tuned symbiotic relationship with microbes. While the effect of environmental change on the composition of the coral microbiome has been heavily studied, we know very little about the composition and sensitivity of the microbiome associated with clams. Here, we explore the influence of increasing temperature on the microbial community (bacteria and dinoflagellates from the family Symbiodiniaceae) harbored by giant clams, maintained either in isolation or exposed to other reef species. We created artificial benthic assemblages using two coral species (Pocillopora damicornis and Acropora cytherea) and one giant clam species (Tridacna maxima) and studied the microbial community in the latter using metagenomics. Results Our results led to three major conclusions. First, the health status of giant clams depended on the composition of the benthic species assemblages. Second, we discovered distinct microbiotypes in the studied T. maxima population, one of which was disproportionately dominated by Vibrionaceae and directly linked to clam mortality. Third, neither the increase in water temperature nor the composition of the benthic assemblage had a significant effect on the composition of the Symbiodiniaceae and bacterial communities of T. maxima. Conclusions Altogether, our results suggest that at least three microbiotypes naturally exist in the studied clam populations, regardless of water temperature. These microbiotypes plausibly provide similar functions to the clam host via alternate molecular pathways as well as microbiotype-specific functions. This redundancy in functions among microbiotypes together with their specificities provides hope that giant clam populations can tolerate some levels of environmental variation such as increased temperature. Importantly, the composition of the benthic assemblage could make clams susceptible to infections by Vibrionaceae, especially when water temperature increases.

Giardiasis is one of the most frequent causes of diarrhoeic diseases in the world. Giardia cysts are most commonly transferred via ingestion of contaminated water or food. On the basis of genetic characteristics Giardia duodenalis is classified in eight assemblages A—H. Zoonotic assemblages A and B are increasingly found in isolates from dogs which may constitute the reservoir of human giardiasis. This article presents a brief review of G. duodenalis assemblages detected in dogs that were documented in European countries.

This study describes Apseudopsis formosus sp. nov., a new apseudomorph tanaidacean species from the Ria Formosa lagoon (southern Portugal). Species description was based on 223 individuals (22 juveniles, 60 males and 141 females), comprising diverse developmental stages (juveniles II, males I and II, preparatory, copulatory and intermediate females). The total length of the studied population ranged from 2.2 to 3.0 mm in juveniles, 2.5 to 4.8 mm in males and 2.9 to 4.9 mm in females. Overall, Apseudopsis formosus sp. nov. differs from congeneric tanaidaceans from the Atlantic Ocean and Mediterranean Sea by the presence of combined different morphological characters such as short pointed rostrum, posterolateral pointed corners on pereonites 2-6, hyposphenium only on pereonite 6, antennular outer flagellum 7- to 10-segmented, inner flagellum 3-segmented and five spines on propodus of pereopod 1, and sexual dimorphism evidenced by a pronounced mid-dorsal triangular wing-shaped protuberance on male merus cheliped, unique in Apseudopsis genus. At each studied developmental stage, some individuals presented abnormalities in spination, having only four spines in one of the propodus of pereopod 1. Additionally, five first records of Apseudopsis from the Algarve coast (A. adami, A. bacescui, A. elisae, A. mediterraneus and A. uncidigitatus) are reported for Portuguese waters. A biogeographic overview of the genus Apseudopsis is presented through the compilation and mapping of all worldwide reported occurrences. Passive dispersion can explain the most recent species distribution, yet not disregarding that the study area is taxonomically understudied. This study contributes to improve the current knowledge on tanaidacean taxonomy and updates the geographical distribution range of the Apseudopsis-complex. Portuguese Fisheries Operational Programme (Mar2020) [MAR-02-01-02-FEAMP-0061] European Maritime and Fisheries Fund (EMFF 2014-2020) Fundacao para a Ciencia e a Tecnologia (FCT)Portuguese Foundation for Science and Technology [SFRH/BPD/94985/2013] Centro de Estudos do Ambiente e do Mar (CESAM) [UID/AMB/50017] FCT/MEC FEDER, within the PT2020 Partnership Agreement FEDER, within Compete 2020European Union (EU)

Entomopathogenic nematodes (EPNs) are well-studied biocontrol agents of soil-dwelling arthropod pests. The insecticidal efficiency of EPNs is modulated by food web dynamics. EPNs can reproduce in freeze-killed insect larvae, even in competition with free-living bacterivorous nematodes (FLBNs) in the genus Oscheius. The objective of this study was to assess the efficiency of EPNs as scavengers when competing with free-living saprophagous nematodes and fungi, and to determine the possible impact on subsequent EPN offspring fitness. Live and freeze-killed larvae of Galleria mellonella were used to evaluate the reproduction rate and progeny fitness of two EPN species, Heterorhabditis bacteriophora and Steinernema feltiae, applied individually or combined with the FLBN species Oscheius onirici or Pristionchus maupasi, or Aspergillus flavus, an opportunistic saprophytic fungus. We hypothesized that (1) EPN scavenging behaviors previously observed (for H. megidis and S. kraussei) apply to other EPN species, (2) infective juveniles (IJs) emerging from freeze-killed larvae will display reduced pathogenicity and reproduction, and (3) fitness reduction will be amplified by exposure to other organisms competing for the resources. The reproduction rate of S. feltiae was lower in freeze-killed larvae than in larvae infected and killed by the nematode, whereas H. bacteriophora failed to reproduce as a scavenger. The S. feltiae F1 IJs that emerged from freeze-killed larvae exhibited lower pathogenicity rates than IJs resulting from entomopathogenic activity, and also lower reproductive rates if they experienced high FLBN competitive pressure during development. This study illustrates that scavenging is a suboptimal alternative pathway for EPNs, especially in the face of scavenger competition, even though it provides a means for some EPN species to complete their life-cycle., This work was supported by the Government of Portugal (FCT), thanks to the “Starting Grant” associate funds (grant number IF/00552/2014/CP1234/CT0007). RCH was awarded with an Investigator Programme contract (FCT, Portugal, grant number IF/00552/2014). Similarly, FAB-P and RB-P were financed by the scientific assistantship fellowships associated with this grant (BI, UAlg-2016/004 and UAlg-2016/003, respectively; Universidade do Algarve, Portugal). Currently, the Government of Spain supports RCH with a Ramon y Cajal contract award (RYC-2016-19939) and the Government of La Rioja (Spain) supports RBP with a predoctoral contract (CAR-2018).

BackgroundGiardia duodenalis is a common human intestinal parasite worldwide, and the causative agent of diarrhea, with the severity of disease ranging from asymptomatic to intense and debilitating infection. G. duodenalis is known to consist of eight genetically distinct assemblages, named from A to H. No data available on the genotypes and genetic diversity of G. duodenalis circulating in Qatar.MethodsWe genotyped 54 human Giardia isolates, collected from asymptomatic immigrants in Qatar, using a multilocus genotyping (MLGs) tool. We also investigated relationships between the subjects’ genotypes and their demographic data.ResultsGenomic DNA from 54 isolates were tested by PCR and sequence analysis at three loci: glutamate dehydrogenase (gdh), β-giardin (bg) and triose phosphate (tpi)). Assemblage A was identified in nine (16.67%), assemblage B in thirty (55.55%), and a mixture of assemblages A+B in fifteen (27.78%) isolates. All assemblage A isolates, genotyped in different loci, were assigned to sub-assemblage AII, and six of them had MLGs AII-1 while one new MLG was identified in two isolates. Sequences of assemblage B isolates have high level of genetic diversity and high presence of heterogeneous peaks, especially within the gdh gene. No significant associations between genotypes and the immigrants’ demographic data were found due to the extensive number of new variants.ConclusionsMLGs was used herein to genotype 54 immigrant Giardia isolates. The high level of genetic variability found in our isolates hampered MLGs determination, more investigations are now required to consolidate our findings, and to enable a comprehensive understanding of the diversity within G. duodenalis assemblage B isolates.

The composition and structure of fish assemblages in the inner continental shelf of the Paraná State are affected by cold fronts and the rainfall regime. Data from fishing activities in this region, as well as the analysis of environmental characteristics, are the main tools available for understanding fish dynamics, under influence of increasing human activities. In order to better understand patterns and temporal variations in fish assemblages in the inner continental shelf of the Paraná State, a total of 24 double trawls were performed with an otter trawl between August 2000 and July 2001, in two sampling areas, the North area in front of the northern mouth of the Paranaguá Estuary Complex, and the South area, in front of the Leste beach. A total of 45,277 fish specimens belonging to 35 families and 97 species were caught. Sciaenidae was the most abundant family, with 37.1% of the total number of individuals caught, and with the highest richness (18 species). Statistical analyses evidenced significant differences in environmental characteristics and in fish fauna, and that both areas disturbances were observed in the fish assemblages during the dry and wet season, being more intense in the Southern area, disturbances that would be related to the shrimp fishing present in the two areas sampled in this study.

Introduction: Rocky outcrops influence both micro and macro habitat for plants and animals by increasing the availability and predictability of food, providing shelter, and unique microclimatic conditions. Objective: We describe the bat assemblage in three isolated rocky outcrops and their surrounding pediments, adding new data about trophic guilds and roosts. Methods: We surveyed the bat fauna of Paraje Tres Cerros, Corrientes Province, Argentina, exploring 13 sites during 26 field trips, using mist nets and search of roosts. We made an accumulation species curve and calculate inventory completeness. The similarity and composition of different habitats was compared by a Non-Metric Multidimensional Scaling (NMDS) and an ANOSIM test. Results: We reported 13 species, with a completeness inventory of the 80 % (Jacknife1), corresponding to the families Vespertilionidae, Molossidae and Phyllostomidae. The insectivorous bats were the best represented guild. We found nine types of roost for eight species in different sites. The analysis expressed low differences in the species composition between both types of habitats in the area. Conclusions: The rocky outcrops and their pediments are important ecosystems for the conservation and diversity of the bats in the region, since their assemblages are regionally unique. Resumen Introducción: Los afloramientos rocosos influyen tanto en el micro como en el macro hábitat de plantas y animales al incrementar la disponibilidad de alimentos, proporcionar refugios y brindar condiciones microclimáticas únicas. Objetivo: Describir el ensamble de murciélagos en tres afloramientos rocosos aislados y sus pendientes circundantes, incorporando nuevos datos sobre gremios tróficos y refugios. Métodos: Muestreamos la fauna de murciélagos del Paraje Tres Cerros, provincia de Corrientes, Argentina, exploramos 13 sitios durante 26 viajes de campo, usando redes de niebla y búsqueda de refugios. Realizamos una curva de acumulación de especies y calculamos la completitud del inventario. La similitud y composición de diferentes hábitats se comparó mediante un escalado multidimensional no métrico (NMDS) y una prueba ANOSIM. Resultados: Reportamos 13 especies, con una completitud del 80 % del inventario (Jacknife1), correspondientes a las familias Vespertilionidae, Molossidae y Phyllostomidae. Los gremios mejor representados fueron los insectívoros. Encontramos nueve tipos de refugios para ocho especies en diferentes sitios. Los análisis expresaron bajas diferencias en la composición de especies entre ambos tipos de hábitats en el área. Conclusión: Los afloramientos rocosos y pendientes son ecosistemas importantes para la conservación y diversidad de los murciélagos en la región, ya que sus comunidades son regionalmente únicas.

Giardia intestinalis continues to be one of the most encountered parasitic diseases around the world. Although more frequently detected in developing countries, Giardia infections nonetheless pose significant public health problems in developed countries as well. Molecular characterisation of Giardia isolates from humans and animals reveals that there are two genetically different assemblages (known as assemblage A and B) that cause human infections. However, the current molecular assays used to genotype G. intestinalis isolates are quite controversial. This is in part due to a complex phenomenon where assemblages are incorrectly typed and underreported depending on which targeted locus is sequenced. In this review, we outline current knowledge based on molecular epidemiological studies and raise questions as to the reliability of current genotyping assays and a lack of a globally accepted method. Additionally, we discuss the clinical symptoms caused by G. intestinalis infection and how these symptoms vary depending on the assemblage infecting an individual. We also introduce the host-parasite factors that play a role in the subsequent clinical presentation of an infected person, and explore which assemblages are most seen globally.

Aim: We tested whether there is a strong effect of species interactions on assembly of local lake fish communities, in addition to environmental filters and dispersal. Location: Seven hundred and seventy-two European lakes and reservoirs. Time period: 1993–2012. Major taxa studied: Nineteen species of freshwater fishes. Methods: We applied a latent variable approach using Bayesian Markov chain Monte Carlo algorithms (R package “BORAL”). We compared the contributions of six environmental predictors and the spatial organization of 772 European lakes in 209 river basins on the presence/absence of the 19 most frequent fish species and on the biomass and mean mass of the six dominant species. We inspected the residual correlation matrix for positive and negative correlations between species. Results: Environmental (50%) and spatial (10%) predictors contributed to the presence/absence assembly of lake fish communities, whereas lake size and productivity contributed strongly to the biomass and mean mass structures. We found highly significant negative correlations between predator and prey fish species pairs in the presence/absence, biomass and mean mass datasets. There were more significantly positive than negative correlations between species pairs in all three datasets. In addition, unmeasured abiotic predictors might explain some of the correlations between species. Main conclusions: Strong effects of species interactions on assembly of lake fish communities are very likely. We admit that our approach is of a correlational nature and does not generate mechanistic evidence that interactions strongly shape fish community structures; however, the results fit with present knowledge about the interactions between the most frequent fish species in European lakes and they support the assumption that, in particular, the mean masses of fish species in lakes are modified by species interactions. Türkiye Bilimsel ve Teknolojik Araştirma Kurumu, Grant/Award Number: 118C250; Spanish Ministry of Science, Innovation and Universities, Grant/ Award Number: RTI2018-095363-B-I00; European Commission; Environmental Investment Centre KIK, Grant/Award Number: 8603/2014; Deutsche Forschungsgemeinschaft, Grant/Award Number: Me 1686/7-1 Türkiye Bilimsel ve Teknolojik Araştirma Kurumu, Grant/Award Number: 118C250; Spanish Ministry of Science, Innovation and Universities, Grant/ Award Number: RTI2018-095363-B-I00; European Commission; Environmental Investment Centre KIK, Grant/Award Number: 8603/2014; Deutsche Forschungsgemeinschaft, Grant/Award Number: Me 1686/7-1

Cryptosporidium spp. and Giardia duodenalis infect the gastrointestinal tracts of animals and humans. Both parasite groups are distributed worldwide and cause significant economic losses in animal productivity. Infected hosts presenting with and without clinical manifestations can eliminate infective forms of these protozoa, which are particularly important to One Health. Compared to the published research on cattle, relatively few studies have examined the epidemiology of cryptosporidiosis and giardiasis in buffaloes. This short review describes the global occurrence of Cryptosporidium spp. and G. duodenalis in buffaloes, including the molecular techniques employed for the identification of species/assemblages and genotypes of these protozoa. Genetic analyses of isolates of G. duodenalis and Cryptosporidium spp. from various sources (environmental, animal, and human) have been performed to investigate their epidemiology. In buffaloes, the species Cryptosporidium parvum, Cryptosporidium ryanae, Cryptosporidium bovis, and Cryptosporidium suis-like have been characterized, as well as assemblages A and E of G. duodenalis. We demonstrate that buffaloes can be infected by species of Cryptosporidium spp. and G. duodenalis assemblages with zoonotic potential. Epidemiological studies that utilize molecular biology techniques represent an important resource for efforts to control and prevent the spread of these protozoans.

Macrofauna play a key role in the functioning of mangrove ecosystems. Nevertheless, our understanding of the diversity and functional structure of macrofaunal communities across different habitats in the mangrove forests of the Persian Gulf is limited. In this study, we investigated species diversity and biological trait patterns of macrofauna in different mangrove-associated habitats, i.e., encompassing actual mangrove forests, and adjacent Beaches and Creeks, which exhibit different levels of habitat heterogeneity. Samples were collected from the different habitats in five different locations, over four seasons. A total of 122 macrofauna taxa were identified. The diversity of species was higher in summer than in winter. In the Beach habitats, species diversity showed an increasing trend from land toward the mangrove, whereas in Creek habitats diversity decreased from the Creek toward the mangrove. Multivariate community analysis showed differences in the distribution of abundant species and biological traits across all habitats. Deposit-feeding, crawlers, medium-size, and free-living were the dominant trait modalities in all habitats. The similarities within habitats over the four seasons had the same specific pattern of species and biological trait abundance in the Beach and the Creek, increasing from the non-covered habitat into the mangrove trees. Although many species shared similar traits, the abundance-driven differences in trait expression between habitats showed the importance of habitat filtering. The results of this study will be useful in the conservation of mangrove forests and they give a deeper understanding of the ecological patterns and functions of benthic macrofaunal communities in the Persian Gulf.

Water mites represent the most diverse and abundant group of Arachnida in freshwater ecosystems, with about 6000 species described, however, it is estimated that this number represents only 30% of the total expected species. Despite having strong biotic interactions with their community and having the potential to be exceptional bioindicators, they are frequently excluded from studies of water quality or ecology, due to actual and perceived difficulties of taxonomic identification in this group. The objective of this study is to use the variations in the sequences of the mitochondrial cytochrome oxidase subunit I (COI), also known as the DNA barcodes region, as a tool to assess the diversity of water mites at 24 sites in the Yucatan Peninsula of Mexico. We found 77 genetic groups or putative species corresponding to 18 genera: Arrenurus, Atractides, Centrolimnesia, Eylais, Geayia, Hydrodroma, Hydryphantes, Hygrobates, Koenikea, Krendowskia, Limnesia, Limnochares, Mamersellides, Mideopsis, Neumania, Piona, Torrenticola, and Unionicola. This was significant, since there are only 35 species described for this region. Furthermore, this molecular information has allowed us to infer that there are characteristic assemblies per site. These data will facilitate the incorporation of water mites in different studies while the curatorial work continues to assign a Linnaean name.

The ecological significance of marine planktonic cyanobacteria in mangrove ecosystems is not well understood from the context of community structure and functions. In this study, members of the marine planktonic cyanobacterial communities were elucidated based on 16S rRNA sequencing (clone libraries and Illumina sequencing) and microscopic approaches from the Sundarbans Biological Observatory Time Series (SBOTS) stations Stn1 and Stn 3 located in and around Mooriganga estuary, Indian Sundarbans over 6 months representing monsoon and post-monsoon seasons of 2012. In total 222 sequences were marine planktonic cyanobacteria-like and were dominated by three major clades of Synechococcus-like 16S rRNA sequences (160 sequences). There was clear dominance of Synechococcus sp. KORDI-78 like sequences (71 sequences) in both monsoon and post-monsoon seasons from the study area. Although in very low numbers, other cyanobacterial sequences showing taxonomic affiliation with members of Chroococcales, Pleurocapsales, Oscillatoriales, and Stigonematales were also encountered. The presence of some of the representative genera belonging to the above Orders were reconfirmed by bright field microscopy from both stations of SBOTS. Presence of four novel clades of planktonic cyanobacteria were also confirmed from the study area based on molecular phylogeny thereby indicating unexplored cyanobacterial diversity is high in Sundarbans. Illumina sequencing undertaken for both stations of SBOTS in one of the monsoon months of 2014 (July) revealed low abundance of cyanobacteria-like sequences (2349 out of 4,276,863 pair-end reads) and dominance of KORDI-78 like sequences. Principal component analysis (PCA) showed that dissolved nutrients, transparency and salinity influenced the observed marine planktonic cyanobacterial assemblages of Sundarbans. There was overall dominance of Synechococcus-like 16S rRNA sequences confirming the importance of small-sized picocyanobacterial cells and their role in export of carbon in mangrove ecosystems.

Tropical forests influence freshwater fish through multiple pathways, only some of which are well documented. We systematically reviewed the literature to assess the current state of knowledge on forests and freshwater fish in the tropics. The existing evidence is mostly concentrated in the neotropics. The majority of studies provided evidence that fish diversity was higher where there was more forest cover; this was related to the greater heterogeneity of resources in forested environments that could support a wider range of species. Studies quantifying fish abundance (or biomass) showed mixed relationships with forest cover, depending on species-specific habitat preferences. We identify the key challenges limiting our current understanding of the forest-fish nexus and provide recommendations for future research to address these knowledge gaps. A clear understanding of the functional pathways in forest-freshwater ecosystems can improve evidence-based policy development concerned with deforestation, biodiversity conservation, and food insecurity in the tropics. Published version

Edges are on the increase world-wide due to increasing fragmentation and loss of natural habitats. After formation, edges are maintained by various processes (natural vs. continued anthropogenic interventions: forestry, agriculture, urbanization) which influence the reaction of individual species to edge effects (history-based edge effect hypothesis), and this will be reflected in the diversity of assemblages. Diversity, however, is not the most appropriate indicator of the edge effect because species with different traits may respond differently to the edges. To further articulate the history-based edge effect hypothesis, we evaluated the edge effect on one of the most commonly used life-history traits, the feeding habit of ground beetles in forest edges. A meta-analysis based on 28 publications and 422 comparisons showed that natural vs. continued anthropogenic interventions as edge-maintaining processes reflected at the trait level. Abundance of herbivorous, omnivorous, and predatory ground beetle species were all higher in the natural edges than in the forest interiors, while no similar pattern occurred in edges with continued anthropogenic influence. These results suggest that structural and environmental changes at edges sustained by repeated anthropogenic influence adversely influencing ecosystem functions, with negative effects on ecosystem services like pest or weed control.

Plastic debris carry fouling a variety of class-size organisms, among them harmful microorganisms that potentially play a role in the dispersal of allochthonous species and toxic compounds with ecological impacts on the marine environment and human health. We analyzed samples of marine plastics floating at the sea surface using a molecular qPCR assay to quantify the attached microalgal taxa, in particular, harmful species. Diatoms were the most abundant group of plastic colonizers with maximum abundance of 8.2 x 10(4) cells cm(-2) of plastics, the maximum abundance of dinoflagellates amounted to 1.1 x 10(3) cells cm(-2) of plastics. The most abundant harmful microalgal taxon was the diatom Pseudo-nitzschia spp., including at least 12 toxic species, and the dinoflagellate Ostreopsis cf. ovata with 6606 and 259 cells cm(-2), respectively. The abundance of other harmful microalgal species including the toxic allochthonous dinoflagellate Alexandrium pacificum ranged from 1 to 73 cells cm(-2). In the present study, a direct relationship between the abundance of harmful algal species colonizing the plastic substrates and their toxin production was found. The levels of potential toxins on plastic samples ranged from 101 to 10(2) ng cm(-2), considering the various toxin families produced by the colonized harmful microalgal species. We also measured the rate of adhesion by several target microalgal species. It ranged from 1.8 to 0.3 day(-1) demonstrating the capacity of plastic substrate colonizing rapidly by microalgae. The present study reports the first estimates of molecular quantification of microorganisms including toxin producing species that can colonize plastics. Such findings provide important insights for improving the monitoring practice of plastics and illustrate how the epi-plastic community can exacerbate the harmful effects of plastics by dispersal, acting as an alien and toxic species carrier and potentially being ingested through the marine trophic web. (C) 2018 Elsevier Ltd. All rights reserved.

Seabird distributions are determined by physical and biological factors operating at variable scales and levels of ecological organization. Accordingly, changes in the composition of the marine avifauna often correspond to large-scale (macro-mega) shifts in water mass properties. Yet, few studies have addressed biogeographical patterns across multiple current systems, spanning from highly-productive to oligotrophic waters. In this study, we characterize the at-sea assemblages of nesting seabirds across the Eastern South Pacific Ocean (ESPO), a vast region spanning from the Humboldt Current to the South Pacific Gyre. Employing multivariate techniques, we first identify four distinct species assemblages and then relate their distributions to the underlying environmental conditions. Our results show that Julian day, depth, sea surface temperature, sea surface salinity, and chlorophyll-α concentration are the most important factors explaining the distribution patterns of these assemblages. Moreover, environmental conditions also explain overall seabird abundance and species richness, two community-level characteristics indicative of ocean productivity. Seabird abundance was best explained by four variables, associated with onshore-offshore gradients (distance to the coast, ocean depth), and the influence of coastal upwelling (mean mixed layer depth, sea surface salinity). Richness was best explained by seasonality (Julian day) and by the presence of water mass boundaries (sea surface temperature coefficient of variation). Our findings underscore the importance of environmental factors structuring the distribution and biogeography of seabirds across gradients of ocean productivity and water mass properties. Understanding the environmental drivers of seabird abundance and richness in the ESPO will inform the prioritization and design of effective marine conservation measures in this poorly studied region.

Analysing the structure and dynamics of biotic interaction networks and the processes shaping them is currently one of the key fields in ecology. In this paper, we develop a novel approach to gut content analysis, thereby deriving a new perspective on community interactions and their responses to environment. For this, we use an elevational gradient in the High Arctic, asking how the environment and species traits interact in shaping predator-prey interactions involving the wolf spider Pardosa glacialis. To characterize the community of potential prey available to this predator, we used pitfall trapping and vacuum sampling. To characterize the prey actually consumed, we applied molecular gut content analysis. Using joint species distribution models, we found elevation and vegetation mass to explain the most variance in the composition of the prey community locally available. However, such environmental variables had only a small effect on the prey community found in the spider's gut. These observations indicate that Pardosa exerts selective feeding on particular taxa irrespective of environmental constraints. By directly modelling the probability of predation based on gut content data, we found that neither trait matching in terms of predator and prey body size nor phylogenetic or environmental constraints modified interaction probability. Our results indicate that taxonomic identity may be more important for predator-prey interactions than environmental constraints or prey traits. The impact of environmental change on predator-prey interactions thus appears to be indirect and mediated by its imprint on the community of available prey.

Fish species assemblage and selected environmental variables were monitored in Lake Volta from September 2014 to August 2016 to determine seasonal variability in species composition, catch and environmental variables that determine the structure of the fish community. A total of 1,557 individual fish belonging to 41 species, 25 genera and 13 families were recorded. The important fish species with respect to frequency of occurrence, abundance and weight, respectively, were as follows: Chrysichthys (100%; 43.03%; 17.93%), tilapias (100%; 28.97%; 17.86%), Alestes (100%; 14.13%; 32.10%) and Bagrus (91.67%; 5.65%; 12.80%) in that order. The composition of fish species and their temporal variation in experimental catches were similar to that of commercial catches. There were no significant differences (p > 0.05) in species abundance, weight and diversity indices between the dry and wet seasons. The modal class of length frequency distribution of the dominant species in the catch, Chrysichthys, reduced from 125 mm in 2006 to 95 mm in the current study indicating overfishing. Environmental variables considered showed little variation and within optimal ranges for fish survival and did not differ significantly between seasons. Canonical Correspondence Analysis showed that environmental variables explained 43.30% of the variation in species abundance with Lake water level, nitrite-nitrogen and total dissolved solids being the main environmental factors influencing the structure of the fish community.

Climate-driven range-shifts create evolutionary opportunities for allopatric divergence and subsequent contact, leading to genetic structuration and hybrid zones. We investigate how these processes influenced the evolution of a complex of three closely related Cystoseira spp., which are a key component of the Mediterranean-Atlantic seaweed forests that are undergoing population declines. The C. tamariscifolia complex, composed of C. tamariscifolia s.s., C. amentacea and C. mediterranea, have indistinct boundaries and natural hybridization is suspected. Our aims are to (1) infer the genetic structure and diversity of these species throughout their distribution ranges using microsatellite markers to identify ancient versus recent geographical populations, contact zones and reproductive barriers, and (2) hindcast past distributions using niche models to investigate the influence of past range shifts on genetic divergence at multiple spatial scales. Results supported a single, morphologically plastic species the genetic structure of which was incongruent with a priori species assignments. The low diversity and low singularity in northern European populations suggest recent colonization after the LGM. The southern Iberian genetic hotspot most likely results from the role of this area as a climatic refugium or a secondary contact zone between differentiated populations or both. We hypothesize that life-history traits (selfing, low dispersal) and prior colonization effects, rather than reproductive barriers, might explain the observed genetic discontinuities. Pew Charitable Trusts (USA); MARINERA, Spain [CTM2008-04183-E/MAR]; FCT (Portugal) [FCT-BIODIVERSA/004/2015, CCMAR/Multi/04326/2013, SFRH/BPD/107878/2015, SFRH/BPD/85040/2012]; FPU fellowship of the Spanish Ministry of Education; European Community ASSEMBLE visiting grant [00399/2012]; University of Cadiz

A monitoring programme was established to collect plankton samples and information of environmental variables over the shelf off the island of Gran Canaria during 2005 and 2006. It produced a detailed snapshot of the composition and seasonal assemblages of the decapod larvae community in this locality, in the subtropical waters of the Canary Islands (NE Atlantic), where information about crustacean phenology has been poorly studied. The larval community was mainly composed of benthic taxa, but the contribution of pelagic taxa was also significant. Infraorders Anomura (33.4%) and Caridea (32.8%) accounted for more than half the total collected larvae. High diversity, relatively low larval abundance throughout the year and weak seasonality characterized the annual cycle. However, in relation to the temporal dynamics of temperature, two distinct larval assemblages (cold and warm) were identified that correspond to periods of mixing and stratification of the water column. The results also indicate that larval release times and durations in the subtropical waters are earlier and longer than at other higher latitudes in the NE Atlantic. We detected the presence of larvae of six species that have not yet been reported from the Canary Islands (Pandalina brevirostris, Processa edulis, Necallianasa truncata, Parapenaeus longirostris, Crangon crangon, Nematopagurus longicornis). Finally, this study provides a baseline for future comparisons with respect to fishery pressure and climate variability in this subtropical region. Durante 2005 y 2006 se estableció un monitoreo para recolectar muestras de plancton e información de las variables ambientales sobre la plataforma insular de Gran Canaria. Esto produjo una instantánea detallada de la composición y estacionalidad de las asociaciones de la comunidad de larvas de decápodos en las aguas subtropicales de esta localidad de las Islas Canarias (Atlántico NE), donde la información sobre la fenología de crustáceos está pobremente estudiada. La comunidad de larvas estuvo principalmente compuesta por taxones bentónicos, pero con una contribución significativa de taxones pelágicos. Los infraórdenes Anomura (33.4%) y Caridea (32.8%) representaron más de la mitad del total de las larvas recolectadas. Alta diversidad, relativamente baja abundancia de larvas a lo largo de todo el año, y débil estacionalidad caracterizaron el ciclo anual. Sin embargo, y relacionado con la dinámica temporal de la temperatura, dos asociaciones larvarias distintas (fría y cálida) fueron identificadas que correspondieron con periodos de mezcla y estratificación de la columna de agua. Los resultados también indican que la duración y periodos de liberación de larvas en las aguas subtropicales son más tempranos y largos en el tiempo en comparación con otras latitudes más altas en el Atlántico NE. Además, se detecta la presencia de larvas de seis especies que no han sido citadas con anterioridad para las Islas Canarias (Pandalina brevirostris, Processa edulis, Necallianasa truncata, Parapenaeus longirostris, Crangon crangon, Nematopagurus longicornis). Finalmente, este estudio supone un punto de referencia para futuras comparaciones en relación con la presión pesquera y la variabilidad climática en esta región subtropical.

Anthropogenic pressures on the marine environment have escalated and shellfish habitats have declined around the world. Recently, Marine Protected Areas (MPAs) have rapidly increased in number and extent, but in Europe as elsewhere, management baselines rarely account for historical conditions.In the present study, the Dornoch Firth protected area (NE Scotland) was investigated as well as three adjacent inlets and 50 km of open coastline. The area has low levels of industrial development, is sparsely populated and conservation features were previously considered “Favourable”. The aim of the present study was to investigate the historical presence of native oyster (Ostrea edulis) beds, a habitat that is now rare and of conservation importance throughout Atlantic Europe.Centred on the protected area, but also gathering broader information from East Scotland, an interdisciplinary review was made of archaeological records, navigational charts, historical maps, museum collections, land-use records, fisheries records, public online databases and naturalists’ records. Intertidal and subtidal surveys were also conducted and sample oyster shells were radiocarbon dated.The present study shows that O. edulis occurred in the inlets and open coast areas of NE Scotland, and specifically in the protected area: Probably since the end of the last glaciation to the late 1800s when they were likely fished to extinction. Habitat restoration in protected areas is an emerging global theme. However, marine habitat restoration is highly unusual and European oyster restoration is presently confined to remnant populations with a clear history of exploitation or dwindling associated fisheries. An interdisciplinary review of baselines will probably show scope for O. edulis restoration in many other European MPAs.

Giardia duodenalis is a flagellated zoonotic parasite that can infect various animals and humans, causing economic losses in husbandry and detriments to public health. Although it has been reported in pigs worldwide, there are few reports on the prevalence and assemblages of G. duodenalis infection in pigs in China. In this study, the 396 pig fecal samples were randomly collected from seven farms in Zhejiang, Guangdong and Yunnan provinces in southern China, and were examined by means of the nested PCR amplification of β-giardin (bg), glutamate dehydrogenase (gdh), and triose phosphate isomerase (tpi) for the detection of G. duodenalis. Overall, 21 fecal samples were positive for G. duodenalis, with a prevalence of 5.3%. Three risk factors are associated with G. duodenalis infection, namely, region, age and gender. Moreover, 13, six and two samples were successfully amplified at the bg, gdh and tpi gene loci, respectively. Three assemblages of G. duodenalis were identified, including assemblage E (n = 17), assemblage A (n = 3) and assemblage B (n = 1). Assemblage E was the dominating genotype and was distributed in three provinces. These assemblages of G. duodenalis have also been found in human beings, non-human primates, sheep, goats and cattle, which further reveals that farmed pigs pose a potential threat to public health.

Nearly 20,000 adult caddisfly specimens were collected during May through September 2010–2014 from approximately weekly ultraviolet light samples of Fairbanks Creek in northern Lower Michigan. Detrended correspondence analysis determined four distinct seasonal assemblages corresponding to spring (May to late June), summer (late June to late July), late summer (late July to early September), and autumn (early to late September). Of the 109 total species caught, 5 indicated the spring assemblage, 13 the summer assemblage, 1 the late summer assemblage, and 4 the autumn assemblage. Species richness, specimen abundance, and number of unique species were highest during the summer. Most summer samples contained ∼50% of all species caught during the year; whereas the spring and autumn assemblage contained a smaller but unique fauna, and the late summer assemblage was characterized by a decreasing richness of summer species. Pollution tolerance and shredder to filtering collector ratio metrics varied by factors of 5–30x; both were highly dependent on the abundance of particular species. Overall mean values of all metrics varied seasonally but not annually. The specific date of peak species richness varied based on annual weather, but occurred at a similar degree-day value for all 5 years. These results suggest the importance of sampling within a season when comparing streams for biological monitoring purposes. Moreover, they confirm the comparability of samples taken from different years, provided such samples are collected during the same season.

Community composition reflects evolutionary and ecological processes such as diversification and species assortment. Communities are generally considered to be saturated, which means that the number of species is maximized and that regulatory mechanisms, such as interspecific competition, prevent the addition of new species. In the tropics, however, species numbers of local bird assemblages double up each winter after the arrival of migratory species, which suggests that a rearrangement of niches occurs. Here ecological space is defined by morphological traits that reflect the ecological position of species, to describe changes in the structure of local communities. We found that the average morphological distance between species was reduced, and the volume (the total extent of trait space) was expanded with the arrival of migrants, indicating that newcomers occupy the periphery and the interior of the available ecological space. Furthermore, with greater morphological differences between resident species, higher numbers of migratory species can take advantage of free space and potentially exploit unused resources due to their intermediate morphology. We highlight the differences in the attributes of resident versus migratory species that may allow both to he accommodated in the morphological space, and we suggest coexistence theory as a possible explanation for the co-occurrence of similar species. (C) 2017 Gesellschaft fur Okologie. Published by Elsevier GmbH. All rights reserved.

International audience; Environmental changes and human activities may have strong impacts on biodiversity and ecosystem functioning. While biodiversity is traditionally based on species richness and composition, there is a growing concern to take into account functional diversity to assess and manage species communities. In spite of their economic importance, functional diversity quantified by a traits-based approach is still poorly documented in tropical estuaries. In this study, the functional diversity of fishes was investigated within four estuaries in Pernambuco state, northeast of Brazil. These areas are subject to different levels of human impact (e.g. mangrove deforestation, shrimp farming, fishing etc.) and environmental conditions. Fishes were collected during 34 scientific surveys. A total of 122 species were identified and 12 functional traits were quantified describing two main functions: food acquisition and locomotion. Fish abundance and functional dissimilarities data were combined into a multivariate analysis, the Double Principal Coordinate Analysis, to identify the functional typology of fish assemblages according to the estuary. Results showed that Itapissuma, the largest estuary with a wider mangrove forest area, differs from the other three estuaries, showing higher mean values per samples of species richness S and quadratic entropy Q. Similarly, it presented a different functional typology (the first two axes of the DPCoA account for 68.7% of total inertia, while those of a traditional PCA based solely on species abundances provided only 17.4%). Conversely, Suape, Sirinhaem, and to a lower extent Rio Formoso, showed more similarity in their diversity. This result was attributed to their predominantly marine influenced hydrological features, and similar levels of species abundances and in morphological traits. Overall, this study, combining diversity indices and a recent multivariate analysis to access species contribution to functional typology, allows to deepen diversity assessment by providing additional information regarding the functional pattern of fish assemblages.

From December 2012 and January 2013 a survey of the herpetofauna diversity was made in forest remnants, farms, open areas, and vegetation around wetlands at a locality in the middle Magdalena River valley, department of Antioquia, Colombia. We recorded 27 amphibian and 36 reptile species. Three of the amphibian species are endemic to Colombia and one is considered threatened; one of the reptile species is endemic to Colombia, and three are categorized as threatened. The species diversity of amphibians and reptiles did not differ significantly between forest and farming areas, but it was higher than in open areas and vegetation associated with wetlands. The species turnover between these two groups of vegetation coverages was higher in amphibians than in reptiles. This differential species turnover level suggests that forest amphibians are more susceptible than the reptiles to deforestation, possibly due to their high dependence of moist microhabitats. Since most forests in the Middle Magdalena River valley of Colombia have been deforested, the conservation of forest remnants that still persist is a priority. Entre diciembre de 2012 y enero de 2013 se caracterizó la herpetofauna en relictos boscosos, cultivos, áreas abiertas y vegetación aledaña a la ciénaga de Barbacoas en una localidad en el valle del Magdalena medio, departamento de Antioquia, Colombia. Se registraron 27 especies de anfibios y 36 de reptiles. Tres especies de anfibios son endémicas para Colombia y una especie está categorizada como vulnerable (VU); una especie de reptil es endémica para Colombia, dos especies están categorizadas como vulnerables (VU) y una en peligro crítico (PC). La diversidad de anfibios y reptiles no difiere entre bosques y áreas de cultivo, pero sí fue mayor en dichas coberturas vegetales que en áreas abiertas y vegetación asociada a ciénaga. El recambio de especies entre estos dos grupos de cobertura vegetal fue mayor en anfibios que en reptiles. Esto sugiere que los anfibios de bosque son más susceptibles que los reptiles a la deforestación, debido posiblemente a su alta dependencia de microhábitats húmedos para sobrevivir y reproducirse. Dado que la mayoría de los bosques en el valle del Magdalena medio de Colombia han sido deforestados, la conservación de los remanentes boscosos que aún persisten es prioritaria.

Giardiasis is considered the most common intestinal parasitic disease in humans worldwide. In Cuba, this infection has particularly a strong clinical impact on the child population. Giardia duodenalis is a highly diverse protozoan, which comprises a complex of eight morphologically identical genetic assemblages, further divided into sub-assemblages. The present study used triose phosphate isomerase (tpi) and small-subunit ribosomal RNA (SSU rRNA) genes as genetic markers for the identification of G. duodenalis assemblages and sub-assemblages in correlation with clinical and epidemiological data in children attended at the Paediatric Hospital “William Soler” and at Pedro Kouri Institute, between 2015 and 2016. A prevalence of 8% of G. duodenalis infection was recorded in stool samples after concentration techniques from 68 children out of 847 analysed. A 100% detection of Giardia DNA was achieved by a SSU-rRNA PCR, whereas DNA from 63 of 68 (92.6%) was successfully amplified by tpi-PCR. By this assemblage-specific tpi-PCR 32 (50.8%) assemblage B, 17 (27.0%) assemblage A and 14 (22.2%) mixed infection (A + B) were identified. Assemblage B was significantly (P

We studied the effects of the overstory canopy cover on ground-dwelling harvestmen communities in European beech forests in the Western Carpathian Mts. We analyzed the differences in species richness, abundance and composition in two tree canopy cover categories (closed and open canopy). Overall, 1765 individuals belonging to 16 species were caught using pitfall traps. Repeated-measures ANOVA revealed that under both closed and open canopies a similar absolute and rarefied species richness and number of individuals (standardized to 100 pitfall trap days) were caught, and that both species richness and abundance were affected by the season (i.e., time of trap replacement); yet the total number of individuals trapped was more than two times greater under the open canopy than under the closed canopy. Despite the subtle differences in the taxonomic composition of the catches under the open and closed canopies revealed by DCA followed by RDA, the composition of ground-dwelling harvestmen assemblages differed under the two canopy covers. The open canopy was more suitable for heliophilic, xerothermic eurytopic harvestmen species typical for open and ecotonal habitats, such as Egaenus convexus (C.L. Koch) and Oligolophus tridens (C.L. Koch) but still suitable for hemihygrophilic Lophopilio palpinalis (Herbst). The closed canopy stands were preferred by shade-tolerant, hygrophilic eurytopic harvestmen species, such as Trogulus sp. Latreille, Dicranolasma scabrum (Herbst) and Platybunus bucephalus (C.L. Koch). Our results highlight the importance of intra-habitat heterogeneity of a harvestmen community.

It is estimated that faecal-orally transmitted diseases are common in Afghanistan, as a consequence of poor hygienic standards of life and widespread contamination of water and food with both human and animal faeces. However, there is little information in the literature concerning infections caused by intestinal parasites in the Afghan population. In this study, we report the occurrence of Giardia intestinalis assemblages (A and B) in formalin-fixed stool samples collected from 245 Afghan schoolchildren living in Ghazni Province in eastern Afghanistan. Detection of the parasite’s DNA and genotyping was performed using real-time PCR, specific to the β-giardin gene of G. intestinalis. Positive results were recorded in 52 (21.2%) samples. Genotyping was successful in 39 faecal samples and showed the predominance of assemblage B of G. intestinalis in this population (15 assemblage A and 24 assemblage B). Co-infection with both genotypes A and B was detected in four samples. Additionally, we evaluated the effect of 10% buffered formalin fixative on the detection of G. intestinalis DNA using real-time PCR and nested PCR characterised by different lengths of PCR products (74 and 479 bp, respectively). The human faeces containing the Giardia cysts were tested for 16 weeks. Amplification of G. intestinalis DNA with real-time PCR was possible up to 6 weeks of preservation of stool sample in formalin, compared to only 2 weeks with nested PCR. This suggests that real-time PCR is a more suitable tool in cases where stool samples have to be kept in formalin for longer periods of time.

An understanding of the forces controlling community structure in the deep sea is essential at a time when its pristineness is threatened by polymetallic nodule mining. Because abiotically defined communities are more sensitive to environmental change, we applied occurrence- and phylogeny-based metrics to determine the importance of biotic versus abiotic structuring processes in nematodes, the most abundant invertebrate taxon of the Clarion–Clipperton Fracture Zone (CCFZ), an area targeted for mining. We investigated the prevalence of rarity and the explanatory power of environmental parameters with respect to phylogenetic diversity (PD). We found evidence for aggregation and phylogenetic clustering in nematode amplicon sequence variants (ASVs) and the dominant genus Acantholaimus , indicating the influence of environmental filtering, sympatric speciation, affinity for overlapping habitats and facilitation for community structure. PD was associated with abiotic variables such as total organic carbon, chloroplastic pigments equivalents and/or mud content, explaining up to 57% of the observed variability and providing further support of the prominence of environmental structuring forces. Rarity was high throughout, ranging from 64 to 75% unique ASVs. Communities defined by environmental filtering with a prevalence of rarity in the CCFZ suggest taxa of these nodule-bearing abyssal plains will be especially vulnerable to the risk of extinction brought about by the efforts to extract them.

Temporary rivers are dynamic freshwater ecosystems, supporting unique and often highly diverse terrestrial communities in the riparian habitats during the flowing phase. However, studies investigating the differences in orthopteran and cockroach (Insecta: Orthoptera, Blattodea) assemblages between riparian and adjacent upland habitats are scarce, despite their abundance and functional importance in terrestrial ecosystems. Orthopterans and cockroaches were sampled in 2014 at 72 sites along the temporary Krcic River (SE Croatia) in two habitat types—riparian and karst, using pitfall traps. Abundance, taxa richness, true diversity and conservation value of ground-dwelling orthopterans and cockroaches were significantly higher in the karst than in the riparian habitat. This result can be ascribed to significant differences in environmental factors: soil temperature, air humidity and vegetation structure, namely tree, shrub and herb layer abundances. Most assemblage parameters and spatial distribution of ground-dwelling orthopteran and cockroach taxa were driven by higher soil temperature and less developed tree layer in the karst, both groups preferring open habitats. Karst sites with a well-developed shrub layer and herb layer had the highest conservation value for rare ground-dwelling orthopterans (e.g. Paramogoplistes novaki) and locally rare cockroaches (e.g. Ectobius balcani), respectively. Nevertheless, densely vegetated riparian sites also harboured some locally valuable species (e.g. Troglophilus cavicola). This study highlights the importance of open karst habitats in promoting the diversity of ground-dwelling orthopterans and cockroaches, and contributes to the understanding of key environmental factors driving their habitat choice, as a prerequisite for efficient conservation and monitoring.

Place: Amsterdam Publisher: Elsevier WOS:000509631400010; International audience; Mangroves are tidal wetlands that are often under strong anthropogenic pressures, despite the numerous ecosystem services they provide. Pollution from urban runoffs is one such threats, yet some mangroves are used as a bioremediation tool for wastewater (WW) treatment. This practice can impact mangrove crabs, which are key engineer species of the ecosystem. Using an experimental area with controlled WW releases, this study aimed to determine from an ecological and ecotoxicological perspective, the effects of WW on the red mangrove crab Neosarmatium africanum. Burrow density and salinity levels (used as a proxy of WW dispersion) were recorded, and a 3-week caging experiment was performed. Hemolymph osmolality, gill Na+/K+-ATPase (NKA) activity and gill redox balance were assessed in anterior and posterior gills of N. africanum. Burrow density decreased according to salinity decreases around the discharged area. Crabs from the impacted area had a lower osmoregulatory capacity despite gill NKA activity remaining undisturbed. The decrease of the superoxide dismutase activity indicates changes in redox metabolism. However, both catalase activity and oxidative damage remained unchanged in both areas but were higher in posterior gills. These results indicate that WW release may induce osmoregulatory and redox imbalances, potentially explaining the decrease in crab density. Based on these results we conclude that WW release should be carefully monitored as crabs are key players involved in the bioremediation process.

Aims Glacial-interglacial climate stability and contemporary climate could affect bird diversity through their direct effects on diversification and physiological tolerance, and indirect effects on plant species richness, which could provide more food and ecological niches. This study aims to quantitatively assess the direct and indirect effects of these drivers on species richness, phylogenetic and functional structure of bird assemblages.Location Mainland China.Taxon Birds.Methods Ordinary least squares models and simultaneous autoregressive models were used to test the associations between glacial-interglacial climate anomaly, contemporary climate, plant species richness, elevation range and species richness, phylogenetic structure, functional structure of bird assemblages in mainland China. Structural equation models were used to distinguish between direct and indirect effects of these variables on bird diversity.Results High bird species richness with phylogenetically and functionally clustered structure occurred in regions with more plant species and stable glacial-interglacial climate. Notably, the phylogenetically clustered bird assemblages were composed of young lineages. Contemporary precipitation and elevation range affected bird diversity through their indirect effects on plant species richness.Main Conclusions These findings suggest that more plant species and stable glacial-interglacial climate may promote bird diversity through their effects on in situ diversification and species dispersal rate in southwestern China. Therefore, the well-preserved plant and bird diversity through the long-term climate fluctuations should be of great importance of biodiversity conservation in China.

Background Very few studies have determined the prevalence and assemblage distribution of Giardia lamblia in South Africa. The present study aimed to ascertain the prevalence of G. lamblia infection and the spread of the various assemblages in two communities in South Africa - Giyani, Limpopo province (rural community) and Pretoria Guateng province (urban community). Methods Prevalence was determined by immunological and molecular methods analyzing a total of 516 stool samples collected from patients visiting different health centres in Giyani and Pretoria. For immunological assays, samples were screened by ELISA to detect G. lamblia antigen. Furthermore, a semi nested PCR amplifying the triose phosphate isomerase (tpi) gene was used to differentiate between the two most common human assemblages (A and B). Findings Of the 516 participants, 40 (7.75%) were identified as positive by ELISA. A statistically significant correlation was observed between the stool texture and Giardia infection (ᵡ2 = 10.533; p = .005). G. lamblia was significantly associated with watery stool types in females p = .008. Furthermore, a significant association was also noticed between the origin of samples (ᵡ2 = 9.725; p = .002). No significant correlation between age and gender was noted. Regarding the age groups, most people who were infected were between 3 and 20 years. A statistically significant association was seen (p = .001) with the distribution of the pathogen with the stool type. The prevalence of Giardia infection was higher in watery stool samples (71.4%) in Giyani region (rural) whereas in Pretoria, high prevalence was found in loose stool samples (6.2%). Generally, the distribution was statistically significant in the stool type collected for the study (p = .005). Genotyping revealed more G. lamblia assemblage B (17.8%) than assemblage A (1.7%). Furthermore, 21.0% of the samples exhibited single infection while 4.2% had mixed infections. Assemblage B was more common in Giyani than in urban Pretoria. Conclusions The study confirms Giardia as an important cause of diarrhea in the concerned communities with people in rural areas more at risk compared to those in urban areas with higher prevalence among younger patients. Therefore, health education campaigns should target young age groups.

Seagrass meadows form vital ecological components of coastal zones worldwide, but are rapidly declining. Large-scale seagrass diebacks have been related to accumulation of toxic sulfide in the sediment, a phenomenon predicted to occur more frequently in the near future due to ongoing global warming and increasing organic loading of coastal systems worldwide. Recently, a facultative mutualism between seagrasses and lucinid bivalves with endosymbiotic sulfide-consuming gill bacteria was discovered that may prevent toxic sulfide accumulation in seagrass sediments. Yet, direct field-based evidence for the importance of this mutualism in alleviating sulfide stress in seagrasses is currently lacking, as well as how its role may change when sediment sulfide levels increase due to environmental change. Here, we investigated the sulfide detoxification function of this seagrass-lucinid mutualism and its resilience to organic-loading induced sulfide stress in a temperate lagoon system (Thau lagoon, France), using a correlative field survey and a full factorial field experiment. The field survey revealed a strong positive correlation between seagrass above-ground biomass and lucinid densities, and pore water sulfide concentrations close to zero at all sites. Furthermore, the field experiment revealed that addition of organic matter (starch mixed with sucrose) increased sedimentary sulfide intrusion into seagrass (Zostera noltei) leaves (a proxy for sulfide stress), while experimentally enhanced lucinid densities reduced sulfide intrusion, regardless of addition of organic matter. Moreover, addition of organic matter reduced seagrass rhizome biomass and increased pore water sulfide levels, lucinid tissue sulfur content, lucinid condition (expressed as flesh/shell dry weight ratio), and total lucinid biomass, while enhancement of lucinid densities reduced lucinid condition. These results provide the first field-based evidence that lucinid bivalves and their sulfide-oxidizing gill symbionts mitigate sulfide stress in seagrasses, and suggests that the dependence of seagrass on this seagrass-lucinid mutualism will increase under conditions of enhanced sediment sulfide production, as predicted for the near future. Therefore, we suggest that awareness of the ecological importance of the seagrass-lucinid mutualism may be instrumental for designing new measures for improving long-term restoration success and seagrass resilience to global change.

Biotic and abiotic characteristics shape the microbial communities in the soil environment. Manipulation of soil, performed by ants when constructing their nests, radically changes the soil characteristics and creates a unique environment, which differs in its composition, frequency and abundance of microbial taxa, from those in the reference soils. We sampled nests of the mound-building ant Formica exsecta, and the surrounding reference soils over a three-month period, and generated NGS (Illumina MiSeq), and T-RFLP data of the bacterial and fungal communities. We used ordination techniques and network analysis to disclose the community structure, and we assessed the variation in diversity, evenness and enrichment of taxa between the two environments. We also used indicator analysis to identify the potential core microbiome of the nests. Our results show that the bacterial and fungal communities, in the rigorously curated nest environment, are significantly different from those in the reference soils, in terms of community structure and enrichment of characteristic indicator taxa. We demonstrate that the nests represent a niche, where microbial species can adapt and diverge from the communities in the surrounding soils. Our findings contribute to our understanding of the composition and function of microbiomes in fragmented habitats.

Complex regimes of stress arise when multiple stressors combine simultaneously, with varying degrees of temporal separation or variation in their sequential order. A manipulative field experiment was run to test whether doses of two stressors (Copper and Biocide) varied in their effects on marine epifauna and ecosystem functioning depending on their sequence, timing and delay before sampling. Our key finding was that time-lags between stressors led to longer-lasting effects. We also found that the sequential order of two stressors influenced effects on measures of ecosystem-level processes: for community respiration (CR) the metal-first sequence of stressors had a negative effect; for clearance rates the biocide-first sequence had the greater effect. Effects of stressors delivered simultaneously on CR and clearance rates were short-lived. Intra-individual effects on cellular viability did not correspond with effects on ecosystem-level variables. Results show that current frameworks for understanding and managing the effects of multiple stressors can be improved by incorporating temporal variation in both cause and effect.

Large-scale spatial variability in plant-pollinator communities (e.g. along geographic gradients, across different landscapes) is relatively well understood. However, we know much less about how these communities vary at small scales within a uniform landscape. Plants are sessile and highly sensitive to microhabitat conditions, whereas pollinators are highly mobile and, for the most part, display generalist feeding habits. Therefore, we expect plants to show greater spatial variability than pollinators. We analysed the spatial heterogeneity of a community of flowering plants and their pollinators in 40 plots across a 40-km(2) area within an uninterrupted Mediterranean scrubland. We recorded 3577 pollinator visits to 49 plant species. The pollinator community (170 species) was strongly dominated by honey bees (71.8% of the visits recorded). Flower and pollinator communities showed similar beta-diversity, indicating that spatial variability was similar in the two groups. We used path analysis to establish the direct and indirect effects of flower community distribution and honey bee visitation rate (a measure of the use of floral resources by this species) on the spatial distribution of the pollinator community. Wild pollinator abundance was positively related to flower abundance. Wild pollinator visitation rate was negatively related to flower abundance, suggesting that floral resources were not limiting. Pollinator and flower richness were positively related. Pollinator species composition was weakly related to flower species composition, reflecting the generalist nature of flower-pollinator interactions and the opportunistic nature of pollinator flower choices. Honey bee visitation rate did not affect the distribution of the wild pollinator community. Overall, we show that, in spite of the apparent physiognomic uniformity, both flowers and pollinators display high levels of heterogeneity, resulting in a mosaic of idiosyncratic local communities. Our results provide a measure of the background of intrinsic heterogeneity within a uniform habitat, with potential consequences on low-scale ecosystem function and microevolutionary patterns.

The plant component of Neanderthal subsistence and technology is not well documented, partially due to the preservation constraints of macrobotanical components. Phytoliths, however, are preserved even when other plant remains have decayed and so provide evidence for Neanderthal plant use and the environmental context of archaeological sites. Phytolith assemblages from Roc de Marsal, a Middle Paleolithic cave site in SW France, provide new insight into the relationship between Neanderthals and plant resources. Ninety-seven samples from all archaeological units and 18 control samples are analyzed. Phytoliths from the wood and bark of dicotyledonous plants are the most prevalent, but there is also a significant proportion of grass phytoliths in many samples. Phytolith densities are much greater in earlier layers, which is likely related to the presence of combustion features in those layers. These phytoliths indicate a warmer, wetter climate, whereas phytoliths from upper layers indicate a cooler, drier environment. Phytoliths recovered from combustion features indicate that wood was the primary plant fuel source, while grasses may have been used as surface preparations. US National Science FoundationNational Science Foundation (NSF) [0917739, 0650198, 0551927] Leakey Foundation University of Pennsylvania Research Foundation Service Regional de l'Archeologie Conseil General de la DordogneRegion Nouvelle-Aquitaine Boston University Graduate Research Abroad Fellowship info:eu-repo/semantics/publishedVersion

Made available in DSpace on 2019-10-06T16:20:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-08-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Ceriantharians or tube-dwelling sea anemones are known for synthesizing soft and flexible tubes made of mucus, cnidae filaments (ptychocysts), and sediments found on the soft bottom. These tubes are used to house and protect them from danger, although many species of marine invertebrates use ceriantharian tubes as alternative substrates. Little is known about the organizational structure of ceriantharians in their own tubes. Although ceriantharians are always considered solitary animals, this study presents the first record of a ceriantharian colony of Botrucnidifer norvegicus Carlgren, 1912. Future studies regarding the population structure in ceriantharian aggregations may help to clarify this unusual habit for Ceriantharia. Departamento de Ciências Biológicas Laboratório de Evolução e Diversidade Aquática – LEDA UNESP - Universidade Estadual Paulista FCL/Assis Instituto de Biociências Departamento de Zoologia UNESP - Universidade Estadual Paulista Centro de Ciências Naturais e Humanas Universidade Federal do ABC Departamento de Ciências Biológicas Laboratório de Evolução e Diversidade Aquática – LEDA UNESP - Universidade Estadual Paulista FCL/Assis Instituto de Biociências Departamento de Zoologia UNESP - Universidade Estadual Paulista FAPESP: 2015/24408-4 FAPESP: 2016/00689-7 FAPESP: 2016/04962-0 FAPESP: 2017/07870-1

The identity, density and spatial and temporal distribution of fish larvae and eggs were investigated in the Gulf of Salamanca, Colombian Caribbean. A total of 49 stations chosen randomly and distributed among the rainy and dry seasons were visited. Due to scarcity of previous studies taxonomic level was restricted to families. Twenty-six fish families were identified and two more could not be identified. Kruskal-Wallis one-way analysis of variance, non-metric multidimensional scaling and Bio-Env analysis were used to test hypotheses and search for patterns. Fish larvae and eggs have a patchy spatial distribution. Temporal distribution suggests a definite influence of seasonality on fish larvae assemblages with the transition time into the dry season (December) correlating to the highest abundance in numbers and biomass of fish larvae and eggs. Resumen Se investigó la identidad, densidad y distribución especial y temporal de larvas y huevos de peces en el Golfo de Salamanca, Caribe Colombiano. Se visitó un total de 49 estaciones escogidas aleatoriamente y repartidas entre las épocas de lluvia y seca. En razón a la escasez de estudios previos el nivel taxonómico se restringió a familia. En total se identificaron 27 familias más dos que no pudieron ser identificadas. Se usaron análisis de varianza Kruskal-Wallis de una vía, escalamiento no métrico multidimensional y el análisis Bio-Env para probar hipótesis y buscar patrones. Las larvas y los huevos de peces tienen una distribución espacial por parches. La distribución temporal sugiere que hay una influencia definida de la estacionalidad sobre los ensamblajes de larvas de peces de modo que el periodo de transición (diciembre) hacia la época seca correlaciona con las mayores abundancias en número y biomasa de larvas y huevos de peces.

International audience; 1. Ongoing global changes are causing major ecological shifts worldwide. Biological trends need to be assessed over long periods of time to better understand past and current community responses.2. The present study developed a methodological framework for meta-analyses to be conducted that account for the temporal and spatial autocorrelation of observational data. We provided the R code for processing this framework, which enables temporal trends to be tested through the analysis of long-term, spatially structured datasets. Taking both types of autocorrelation into account resulted in more conservative but arguably more reliable statistical outcomes.3. This meta-analysis framework was then applied to investigate long-term trends in environmental and fish-community time series in multiple stations in large French rivers over the past 4 decades.4. General significant upward and downward trends were highlighted in water temperature and flow discharge, respectively, over the study period. Concomitantly, the density of numerous species increased, resulting in large increases in both species richness (about + 50%) and total fish abundance (approximately four-fold), but with no significant trend in species evenness. Strong changes in species composition were observed during the study period, with an overall upward trend in the relative abundance of newcomers (i.e. species not sampled during the first years of the survey), while the trend in relative abundance of non-native species was non-significant. Moreover, the strongest signal underlying community changes was replacement of northern by southern species. 5. This study showed major changes in fish density and community structure in large rivers over the past 40 years and represents, to our knowledge, one of the first large-scale actual demonstrations (i.e. based on observations rather than predictions) of an overall poleward shift of freshwater fish communities in response to ongoing global changes. K E Y W O R D S global changes, long-term surveys, meta-analysis, poleward shift, spatio-temporal autocorrelation This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.