Stream development can generate environmental changes that impact fish communities. In temperate streams, the distribution of fish species is associated with environmental gradients. To analyze the relevant factors, large-scale exploration is required. Thus, to evaluate the distribution patterns of fish in Korea, sampling was conducted on a national scale at 720 sites over a 6-week period in 2009. A total of 124 fish species in 27 families were identified; Zacco platypus and Zacco koreanus of the Cyprinidae were the dominant and subdominant species, respectively. Of the species found, 46 (37.1%) were endemic and 4 (3.2%) exotic; of the latter, Micropterus salmoides and Lepomis macrochirus were widely distributed. Upon canonical correspondence analysis (CCA), both altitude and biological oxygen demand (BOD) were highly correlated with CCA axes 1 and 2, respectively. This explained 62.5% of the species–environment relationship. Altitude and stream order were longitudinally related to species distribution. The numbers of both total and endemic species gradually increased as streams grew in size to the fourth–fifth-order, and decreased in sixth-order, streams. Overall, fish communities were stable throughout the entire watershed, whereas some species showed site-specific occurrence patterns due to the paleogeomorphological characteristics of Korean peninsula. However, various anthropogenic activities may negatively affect fish communities. Therefore, both short- and long-term sustainable management strategies are required to conserve native fish fauna.

Considerable spatial and temporal variability was detected in the environmental conditions in 30 coldwater springs in southernOntario, Canada. Using standard pyramidal emergence traps, a total of 86 insect species was recorded from these springs (notincluding the Chironomidae). These represented nine taxonomic groups, among which the Limoniidae (Diptera) was the mostdiverse with 38 species. Fifty-five per cent of all species recorded had a low frequency (found at three or fewer sites), and onlyfor very few of these rare species were more than 10 individuals m-2 collected. Interannual differences were also apparent.Continuous sampling over time showed that emergence records from a single year, on average, contained only around 50% ofthe total number of species obtained during the entire study. Species-environment relationships analyzed by CanonicalCorrespondence Analysis indicated that temperature and discharge correlated most strongly with insect community similarityamong spring sites. The prospects for developing regional typologies of coldwater springs, based on their environmental conditions,and the implications of species loss to the continuity of function of coldwater spring ecosystems are discussed.

Rainbow trout is one of the most popular introduced game species around the world. Similar patterns of use for lake and inlet streams have been described for both native and introduced populations. However, for many introduced rainbow trout populations, there is a lack of information about how and when those habitats have been used. Here, we hypothesized that the majority of adult and sexually mature individuals inhabit inlet streams during the reproductive period most likely to spawn whereas juvenile trout occupy these same streams as nursery areas most of the year before emigrating to the lake. We studied rainbow trout age distribution and sexual maturity in a lake and its main inlet streams in southern Chile. We found that stream-dwelling individuals inhabited inlet streams up to age 2+ whereas lake-dwelling trout were older (most of them from ages 4+ to 6+). During the reproductive period (May to September) older and sexually mature individuals were in both habitats probably indicating movement to upstream locations to spawn. Rainbow trout of the same ages were larger in the lake than in streams, which may imply better growth in the lenthic environment. Our study offers further evidence of the highly adaptable nature of rainbow trout. Future regulations should consider rainbow trout populations in lakes and streams separately because trout life histories suggest that both environments are important to different ontogenic stages. This study provides key information that may be useful in the management of ad-fluvial populations of rainbow trout in Patagonia.

The ichthyofauna of the River Minho tidal freshwater wetlands (TFWs) was studied in a semi-enclosed area, between June 2007 and May 2010, to determine temporal patterns of abundance, biomass and species composition. Fish catches, standardized by the number of fyke nets and by the fishing effort, were analysed and related to river flow, water temperature and precipitation. In total, 21 fish species were identified including six non-indigenous species (NIS) which represented 15% of the total captures (yet 43% of the biomass). Regarding ecological guilds, 82% were freshwater species (61% of the biomass) which included all NIS, whereas 13% of the catches were catadromous species (31% biomass) corresponding to eels. Only 4% were estuarine species (1% biomass) and together marine estuarine opportunists and anadromous species accomplished 1% (2 and 6% biomass, respectively). The fish assemblage showed seasonal patterns with a clear distinction between autumn/winter and spring/summer periods. Significant differences in abundance and biomass were also detected between autumn/winter of 2007/2008 and 2008/2009, i.e., inter-annual variations, with the latter period with lower catches yet higher dominance of NIS. Besides, higher water temperature had a significant negative effect on the observed number of species, but a positive effect on the abundance and biomass of NIS. More attention has to be given to TFWs and their role in structuring fish assemblages, because this information is vital for a sound management, conservation and restoration of estuarine areas.

Ce travail est une contribution à la connaissance faunistique et écologique des oligochètes de deux cours d'eau du Midi de la France : l'Argens et un de ses affluents, l'Eau Salée. Nous présentons une première diagnose d'un Tubificidae indéterminé du genre Peloscolex et nous donnons un complément à la description d'Epirodrilus pygmaeus Hrabe qui est signalé ici pour la première fois en France. Nous abordons également quelques points intéressants concernant la répartition géographique de certaines espèces : Chaetogaster setosus Svetlov, Tubifex tubifex blanchardi Vejdovsky, Epirodrilus pygmaeus Hrabe et Lumbri-cillus kaloensis Nielsen et Christensen.

Les périodes de maturité observées pour les oligochètes de ces cours d'eau sont récapitulées dans un tableau. A partir de nos observations et des données de la littérature nous précisons les préférendums écologiques de chacune des principales espèces avant de conclure sur la répartition longitudinale des oligochètes dans ces deux cours d'eau.

The population dynamics and life cycle of two mollusc species Pisidium amnicum and Valvata piscinalis of the Saône river werestudied for nine years. The newborn of the former species appeared in April each year. The latter species produced two cohorts peryear until 2003. Spawning in spring led to the birth of the early cohort, which generally appeared in May, while spawning in thesummer led to the birth of the late cohort, which appeared from July to November. The increase of the mean annual temperature by1.9°C from 1998 to 2000 was followed by an increase in the density of mollusc populations, possibly triggering or amplifying interand intra specific competition for food. However, the 2003 heatwave was responsible for the sudden decline of the P. amnicumpopulation, then the more progressive decline of that of V. piscinalis after having strongly modified its demographic structure andits life cycle. In 2004 and 2005 V. piscinalis only produced one cohort per year. The observations carried out strongly suggest thatthe insufficiency of available resources was one of the possible causes of their failure to recover in 2004 and 2005. The increase ofglobal warming predicted by different models could result in the gradual disappearance of P. amnicum from the potamon and ofV. piscinalis from the freshwater systems most directly exposed to climatic warming, such as the Saône River.

This paper focuses on relationships between the North Atlantic Oscillation Index (NAO) and the ice conditions in coastal lakes (Jamno, Bukowo, Gardno and Lebsko) of the southern Baltic Sea. The data on ice conditions included : date of first ice appearance (F), date of last ice disappearance (D), number of days with ice (N), length of the ice season (in days ; S) and maximum ice thickness (H) during the given winter. The period examined covers the winters from 1960/61 to 1999/2000. The monthly values of the NAO index for the same period were applied in accordance with Jones et al. (1997). Correlation and regression analysis methods were applied to determine and study the relationships between NAO (independent variable) and the parameters of ice conditions (dependent variables). The strongest relationships, with a linear correlation coefficient exceeding - 0.80, were obtained for the date of the last ice disappearance (D) in Lebsko Lake (- 0.853) and Gardno Lake (- 0.828) for the January March period. In contrast, the relationships between the NAO index and the date of first ice appearance (F) are much weaker. They are statistically significant only in November and early winter (Nov.-Dec., Nov.-Jan.). The correlation coefficients in the coastal lakes of the Southern Baltic Sea coasts generally increase eastwards, a phenomenon related to the severity of winters and to the increasing continuity of ice phenomena during a given winter in this direction.

Cladocerans are used in a wide range of applications (aquatic toxicology, experimental hydrobiology, and aquaculture). Although known to be successfully cultivated with microalgal food sources, cladoceran demographic parameters tend to be different, depending on the kind of cladoceran and concentration of food supplied. For most species, finding precise instructions on culture conditions and expected outcomes is difficult. The aim of this study was to determine the most favorable feeding conditions for the development of three cladoceran species frequently used as test organisms in aquatic toxicology. For this purpose, Ceriodaphnia dubia, Daphnia pulex, and Simocephalus mixtus were fed three concentrations (6, 12, and 18 mg L-1 dry weight) of the green microalgae Ankistrodesmus convolutus, Pseudokirchneriella subcapitata (formerly Selenastrum capricornutum), and Scenedesmus incrassatulus. Reproduction and survival were evaluated during the entire life cycle. For C. dubia, the P. subcapitata and S. incrassatulus diets produced the best reproductive results. For D. pulex, the best overall results were obtained with S. incrassatulus at 6 mg L-1 and results with P. subcapitata were similar at all concentrations. For S. mixtus fed P. subcapitata, results were similar at all concentrations. With S. incrassatulus, a decrease in longevity and an increase in fecundity occurred as the amount of food increased; the best reproductive response was achieved with the highest (18 mg L-1) concentration. The lowest reproduction and survival in the three cladocerans were recorded with A. convolutus. For the cladoceran species tested, the same microalga produced different reproductive and survival results, depending on the concentration; some of the tested foods did not support adequate cladoceran development, because they were nutritionally deficient, despite the similar conditions used for their production. Feeding and culture conditions here described could be useful for a controlled propagation of these cladocerans.

Au cours d'un séjour aux Marismas du Guadalquivir (30 avril-17 mai 1965), l'auteur a étudié quelques Invertébrés des principaux milieux aquatiques.

7 Ostracodes, 13 Cladocères, 19 Hétéroptères, 10 Hydracariens sont nouveaux pour les Marismas et certains d'entre eux pour l'Espagne.

La répartition des espèces dans les stations et leur biogéographie sont envisagées.

Toxic cyanobacteria are common in Portuguese freshwaters and are a cause of concern, given that exposure to subacutelevels of cyanobacterial toxins through drinking and recreational water might have deleterious effects on human health.Since 1996 several laboratories have been involved in the screening of cyanotoxins in different freshwater bodies, some on aregularly basis but most on a sporadically basis. Here we present data on the phytoplankton communities and on microcystinsproduction occurring in six freshwater reservoirs located in a dry region of south Portugal, from May to December 2005 andApril to July 2006. Most of the reservoirs experienced cyanobacterial blooms of various intensities, following noticeable shiftsin phytoplankton composition towards cyanobacterial dominance. The seasonal dominance of cyanobacteria during warmerperiods was not a fi xed pattern since considerable amounts of cyanobacteria were also recorded during winter months in somereservoirs. Microcystins were detected in 23% of the 53 samples tested and some of them had concentrations higher than theWHO guideline of 1μg L-1 of microcystins, but their amounts not always reflected the encountered cyanobacteria biomass.Although Microcystis aeruginosa seems to be the major species responsible for microcystins production, other potentiallytoxigenic bloom-forming species were also found. These results reflect the irregular and unpredictable nature of cyanobacterialblooms in what respects to their occurrence, their composition, their intensity and persistency, as well as to their overall toxicity,strengthening the need of a systematic survey of freshwater resources for the correct risk assessment of cyanobacteria andassociated toxins in natural environments.

The objectives of this study were to evaluate fish guild compositions and national river health using a multi-metric model of the Korean index of biological integrity using fishes (K-IBIF) in four major Korean watersheds along with water chemistry and habitat quality. Tolerant and omnivore fish species dominated all the watersheds, and the proportions of tolerance guilds and trophic guilds reflected water chemistry and habitat quality. The number of sensitive species and insectivore species had negative correlations (r < −0.42, P < 0.01) with chemical water quality (biological oxygen demand (BOD)), while tolerant species and omnivore species had positive correlation (r > 0.27, P < 0.05) with BOD values. Physical habit conditions, based on qualitative habitat evaluation index (QHEI) model, indicated a “good” condition (mean = 68.9; range = 45–105) in three watersheds, except for the Yeongsan River watershed. Values of QHEI were significantly correlated (R2 > 0.4, P < 0.01) with nitrogen and phosphorus levels in all watersheds, suggesting that habitat degradation is associated with eutrophication. Model values of K-IBIF in the watersheds averaged 18.2, indicating a “fair” condition, and about 37% of all observations in K-IBIF model values were judged as a “poor” health condition, indicating severe health impairment. Overall, our data suggest that degradation of the river health was due to a combined effect of chemical pollution and physical habitat modifications. This research provides valuable information on Korean river conservation and restoration in the future.

As part of a wetland conservation programme for the Southern shore of lake Neuchatel (Western Switzerland), an experiment was started in 1993 to slow down the terrestrialization of the wetland. Sediments were removed in a reed-belt adjacent to an existing pond, at three different depths (0.20, 0.30 and 0.40 m), thus creating a new shallow pond. The colonisation by aquatic vegetation and invertebrates was monitored during three years (1994–1996) to evaluate the effect of the creation of a new pond on the chironomid diversity and abundance through time. Chironomids (78 taxa) were among the most diverse group colonising this fringing wetland. Significant differences in abundance were found between the reed-belt and the pond habitats (existing and recently created ponds). As expected, the latter was more productive, especially during the first two years of colonization. However, the chironomid diversity in the newly created pond, measured by the rarefied richness, was intermediate between the reed-belt (low diversity) and the pre-existing pond. Ordination of the sites on the basis of their chironomid assemblages confirmed this trend. The depth at which the sediment was scrapped off, had no major influence upon the chironomid assemblages. Finally, within the three years after creation of open water habitats, the production of chironomids and consequently their availability for dabbling ducks and wetland birds, were enhanced. However, this time was not enough for the chironomid community to reach the diversity of the pre-existing pond, to which it is connected. The creation of shallow ponds seemed to be crucial to slow down terrestrialization processes in this lacustrine wetland and to have only slight effects on the chironomid communities.

Thirty-six chrysophycean stomatocysts are reported from the dystrophic Staw Toporowy Nizni lake in the Tatra National Park, Poland. Of these, 7 morphotypes are new to science, 10 are new to Europe, and 13 are new to Poland. SEM micrographs and data on distribution are provided for each stomatocyst. Synonimizations of two stomatocysts are proposed: stomatocyst 58 Hansen 2001 with stomatocyst 117 Zeeb et al. 1990, and stomatocyst 91 Hansen 2001 with stomatocyst 239 Duff et al. 1995. The number of chrysophycean stomatocysts recorded from Poland is currently estimated to comprise 65 extant morphotypes.

La comparaison de ruisseaux temporaires et permanents a été réalisée afin de déterminer leurs affinités. On a noté une stabilité des facteurs physiques et chimiques dans les ruisseaux permanents et pendant la phase lotique des ruisseaux temporaires; la phase stagnante des ruisseaux temporaires se révèle très instable. La comparaison des facteurs biotiques révèle l'affinité des ruisseaux permanents calmes et des ruisseaux temporaires. Les ruisseaux permanents à cours rapide et les ruisseaux temporaires sont peu affines. Quelques populations spécifiques peuvent survivre à la période sèche des ruisseaux temporaires, seulement lorsque la nappe phréatique est présente en profondeur.

L'estimation de la qualité des cours d'eau, à la fois en terme de milieu physique et de qualité de l'eau, est une nécessité croissante. Les « indices macrophytes » peuvent être utilisés en complémentarité de méthodes plus usuelles, analyses d'eau ou indices biotiques. Certains indices macrophytes proposés par la littérature ont été appliqués et testés sur 5 rivières du Nord de la France, correspondant à des substrats géologiques et à des situations de pollution et/ou de trophie contrastées. Ce sont : le Diagnostic Phytoécologique à partir des indices d'Ellenberg, le Plant Score de Harding, l'Indice Trophique de Newbold & Holmes, le Taux de Dommage de Haslam. Une comparaison avec les analyses d'eau a été réalisée. Les diagnoses sont globalement concordantes, mais leur acuité est variable. Les listes d'espèces fournies par les auteurs sont en général très incomplètes et éludent de nombreux problèmes de taxonomie. Le niveau de bioindication (notion de « trophie », paramètre écologique analytique comme les orthophosphates, ...) en fonction de l'état physique du cours d'eau, est rarement précisé. Les indices proposés dans les trois premières méthodes citées sont rarement étayés par l'analyse détaillée des distributions espèces/facteurs (profils écologiques). La méthode de Haslam présente un caractère intégrateur marqué fondé sur l'écologie des cours d'eau, même si l'aspect floristique est incomplet. Son application en France est obérée par la méconnaissance des phytocénoses de référence et des séquences de dégradation, et par l'absence d'une grille précise de trophie-substrat géologique nécessaire pour l'estimation des altérations de la qualité de l'eau. Les méthodes de Harding et de Newbold & Holmes sont de mise en œuvre plus simple et donnent des indications assez cohérentes. Malgré ces réserves, la définition d'indices semble intéressante et correspond à une demande des gestionnaires. Des propositions d'amélioration des méthodes existantes, ainsi que des éléments pour l'élaboration d'un indice synthétique sont présentés.

Three new genera of Baetidae (Ephemeroptera) are described from larvae from South America. Adebrotus Lugo-Ortiz & McCafferty, n.gen., and its type species, A. amazonicus Lugo-Ortiz & McCafferty, n.sp., were taken from Amazonas, Brazil. The genus possesses numerous unique mouthpart characteristics, including a labrum with distinct anteromarginal protrusions, a left mandible with the inner incisors rotated to a right angle with the flat plane of the mandible, a right mandible with a large denticle in the midregion of the mola, unusually shaped galealaciniae with distally pectinate setae, and an unusually shaped labium. Tomedontus Lugo-Ortiz & McCafferty, n.gen., and its type species, T. primus Lugo-Ortiz & McCafferty, n.sp., were taken from Amazonas and Pará, Brazil. The genus possesses a trapezoidal labrum lacking an anteromedial emargination, a distomedial process on the hypopharyngeal superlinguae, laterally denticulate mandibles, and unusually shaped maxillae and labium. Waltzoyphius McCafferty & Lugo-Ortiz, n.gen., and its type species, W. fasciatus McCafferty & Lugo-Ortiz, n.sp., were taken from Amazonas and Pará, Brazil, and Paraguarí, Paraguay. The genus is distinct in that the maxillae have only falcate denticles on the galealaciniae,the labium is unusually shaped, and the midsternum has an acute medial spur.

In this study, we investigated variation in offspring size (OS) of Daphnia magna in relation to multiple maternal traits and environmental variables. Data originated from laboratory experiments conducted at different feeding scenarios. The mother daphnids had different life-history traits and were reared under various feeding and density conditions. OS showed linear relationships with maternal traits, varying positively with maternal body size, age and brood number, and negatively with brood size and with the amount of ingested carbon. OS increased exponentially with crowding. Using stepwise multiple regression analysis, we developed an empirical model for the OS variation with the relevant maternal and environmental variables. Density dependence was considered by multiplying the resulting model by a density-effect function. We found that the ingested carbon and the maternal body size were the strongest determinants of the observed variation in the OS, whereas the brood size had the least impact on OS. Additionally, the brood number had no significant effect in determining the variability in the OS. The validity of the multivariate model was tested against an independent dataset. The model accurately predicted the OS despite several genetic and environmental differences compared with the data used for parameterization.

Le mâle de Brachyptera braueri introduit d'abord son épiprocte dans le vagin. Après une longue phase de stimulation, il dépose un spermatophore externe. Chez les Brachyptera, il existe une corrélation interspécifique entre la longueur des filaments de l'épiprocte et du flagelle du paraprocte droit des mâles et la longueur du canal du réceptacle séminal des femelles. Les oeufs de B. braueri éclosent au bout de trois à sept semaines. Ceux de Perlodes microcephalus éclosent soit deux à cinq mois après la ponte, soit un an après. La chétotaxie des premiers stades larvaires des deux espèces est décrite et figurée en détail. Les transformations évolutives du stade I et de l'adulte montrent un curieux parallélisme, à la fois pour les cerques des Nemouroidea et les pièces buccales des Subulipalpia.

South American species of small minnow mayflies (Insecta : Ephemeroptera : Baetidae) that have been previously placed in Baetis Leach or Pseudocloeon Klapálek are revised. Species that resided in Baetis are shown to include Camelobaetidius alcyoneus, n. comb., C. coveloae, n. comb., C. dryops, n. comb., C. tantillus, n. comb., Cloeodes nocturnus, n. comb., C. stelzneri, n. comb., Fallceon inops, n. comb., F. murphyae, n. comb., F. yaro, n. comb., Moribaetis aneto, n. comb., M. comes, n. comb., and M. socius, n. comb. Species that resided in Pseudocloeon are shown to include Americabaetis albinervis, n. comb., A. bridarolli, n. comb., A. bruchi, n. comb., A. jorgenseni, n. comb., A. oldendorffi, n. comb., A. peterseni, n. comb., A. weiseri, n. comb., Cloeodes turbinops, n. comb., and C. venezuelensis, n. comb. The bases of the revisions are discussed under each species. The presence of Fallceon and Moribaetis in South America is confirmed for the first time.

We examined the associations of microorganism assemblages with a complete mineral richness gradient spanning from extremely mineral-rich tufa-forming calcareous fens to mineral-poor acidic Sphagnum-fens. We also compared the distribution of two dominant taxa, testate amoebae and monogonont rotifers, among the sites differing in water chemistry and among three microhabitats sampled at each site differing in substrate and moisture conditions. Microorganism assemblages primarily changed in relation to the mineral richness gradient; moisture was the second most important factor structuring microorganism assemblages among microhabitats (i.e., wet bryophytes, submerged bryophytes and waterlogged bottom sediments). Densities of testate amoebae taxa and individuals were the highest in rich Sphagnum-fens, indicating a unimodal pattern along the mineral richness gradient. Numbers of testate amoebae taxa decreased notably in wet bryophytes, especially in poor Sphagnum-fens. This pattern might result from a strong effect of Sphagnum acidification due to minimal or no dilution of the acidic environment by mineral-rich groundwater. As a consequence, acid tolerant and relatively xerophilous taxa chiefly dominated in wet bryophytes of poor Sphagnum-fens, while poor Sphagnum-fen bottom sediments could provide a refuge for less tolerant and hydrophilous species. In contrast to testate amoebae, monogonont rotifers preferred bryophytes in all sites, with the number of monogonont taxa distinctly increasing from calcareous fens to poor Sphagnum-fens. In poor Sphagnum-fens, monogononts were the most abundant in wet bryophytes, probably due to reduced food competition and/or predaceous pressure resulting from the limited occurrence of other groups of microorganisms by virtue of the hostile acidic conditions in wet Sphagnum carpets.