Academic literature on the topic 'Cottus gobio'

Abstract In the protected area ROSCI0229 Siriu were named three fish species of community interest: Gobio uranoscopus frici Vladykov, 1925, Barbus petenyi Heckel, 1847 and Cottus gobio Linné, 1758. Out of 193 fish collected in 2010, 49 were Barbus petenyi and 37 Cottus gobio. In the three monitored rivers (Buzău River, Siriu River, and Crasna River), Barbus petenyi was present in two of them and Cottus gobio was present in all of them. According to the analytical indices of population, frequency, numerical abundance and density we assessed a favorable population status for Barbus petenyi in Buzău River and a medium favorable population status for Cottus gobio in Buzău River and its tributaries Crasna River and Siriu River.

Abstract Cottus gobio is considered a fish species of conservation concern within the Vişeu Watershed. The habitats state, usually populated by Cottus gobio within the Maramureş Mountains Nature Park (Vişeu and Bistriţa Aurie watersheds) vary among reduced (34.42%), average (45.91%), and good (19.67%). The excellent conservation status is currently missing for populations of this fish in the Vișeu Basin. Human impact categories were inventoried as inducing the diminishment of Cottus gobio habitats and populations in the researched area in comparison with its natural potential are: minor riverbed morphodynamic changes, liquid and solid natural flow disruption, destruction of riparian tree and shrub vegetation, habitat fragmentation-fish populations isolation, organic/mining pollution activities, fish washing away at floods, and poaching.

Abstract The Bistra Mărului River fish fauna has been severely impacted by man-made activities, especially through longitudinal fragmentation, over the past 40 years. Fish fauna monitoring revealed structural changes and technical methods have been proposed, in order to restore the natural connectivity and the conservation of fish species. Benefits should accrue for key species: Salmo trutta fario, Cottus gobio, Thymallus thymallus, Eudontomyzon danfordi, Eudontomyzon vladykovi, Gobio uranoscopus, Barbus meridionalis, and Condrostoma nasus.

We assessed the biomass and stable-isotope composition (δ13C and δ15N) of consumers (aquatic insects and fish (Cottus gobio)) and potential food sources (detritus, biofilm, seston, algae, and mosses) in channelized and restored streams in Sweden, assessing the hypotheses that restoration enhances detritus storage and detritus-based secondary production. Restored sites stored more detritus than channelized sites, with differences (+5.4% on average) prominent in margins, i.e., the channel area within 1.4 m from the banks. The biomass of other resources was similar between restored and channelized sites. Most common aquatic insects, including several putative detritivores, showed δ13C values indicating reliance on aquatic (probably algal) carbon sources. The insectivorous fish Cottus gobio, on the contrary, appeared to be more dependent on terrestrial (detrital) carbon sources. The biomass and mean δ13C values of the consumers were similar between restored and channelized sites, suggesting that restoration did not increase net secondary production or the fraction of secondary production based on detritus. We concluded that the increase in detritus storage at restored sites was either insufficient to enhance detritus-based production or the consumers were not limited by the availability of detritus.

AbstractAlthough small benthic freshwater fish species are an important biological component of fish assemblages and free instream movement is indispensable for their survival, they are often neglected in fish pass performance studies. In this study, a capture-mark-recapture approach was used to assess whether small bottom-dwelling species, including gudgeon (Gobio gobio), stone loach (Barbatula barbatula), spined loach (Cobitis taenia) and bullhead (Cottus gobio), were able to cross a pool-and-weir fish pass in a regulated lowland river. Some tagged individuals of stone loach (18%), gudgeon (7%) and spined loach (2%) managed to successfully ascend the fish pass under study, despite the fact that water velocity levels in the different overflows of the facility (between 0.55-1.22 m/s) exceeded the critical swimming speed of all three species. Although this suggests that a pool-and-weir fish pass is a able to facilitate upstream movement of some small benthic species in a regulated river, more detailed research incorporating advanced tagging and retrieving techniques is necessary.

La température de l'eau joue un rôle majeur dans le cycle de vie des poissons. Dans un contexte de changement climatique global, le réchauffement peut avoir un impact fort sur la croissance, la fécondité et la survie. L'enjeu de cette thèse est la modélisation mathématique de l'influence de la température sur les traits d'histoire de vie d'une population de chabot (Cottus gobio) afin de faire de la prédiction à la fois au niveau individuel et populationnel. Les données expérimentales qui permettront de calibrer les modèles sont issues du bassin de la Drôme (France) et plus particulièrement du sous-bassin du Bez. Dans une première étape, il s'agit de développer un modèle de rétrocalcul qui peut être utilisé pour calculer les longueurs individuelles des chabots aux âges précédents à partir des données mesurées à la capture. Il s'agit, dans un deuxième temps, de développer un modèle de croissance dépendant de la température de l'eau qui sert à prédire la longueur moyenne des chabots à un âge donné. Enfin, il s'agit de passer de l'échelle de l'individu à celle de la population en prenant en compte tous les traits d'histoire de vie et leurs dépendances vis-à-vis de la température. Plus précisément, un modèle matriciel de type Leslie, à la fois dépendant du temps et de la température, structuré en classe d'âges est développé et utilisé pour prédire la dynamique de population sous différents scénario du réchauffement climatique
Water temperature plays a key role in the life cycle of fish. Therefore, increasing temperatures due to the expected climate change may have a strong impact on growth, fecundity and survival. The goal of this thesis is to model the impact of temperature on the life-history traits of a bullhead population (Cottus gobio) in order to make predictions both at individual and at population level. The models developed here are calibrated on experimental field data from a population living in the Bez River network (Drôme, France). First, a new back-calculation model is derived that can be used to compute individual fish body lengths at earlier ages from capture data. Next, a growth model is proposed that incorporates the water temperature and can be used to predict the mean length at a given age and temperature. Finally, the population is modelled as a whole by linking all life-history traits to temperature. For this purpose, a spatialised time- and temperature-dependent Leslie matrix model structured in age classes was used to predict the population dynamics under different temperature scenarios

Riverine physical habitats and habitat utilization by fish have often been studied independently. Varying flows modify habitat composition and connectivity within a stream but its influence on habitat use is not well understood. This study examined brown trout (Salmo trutta) and bullhead (Cottus gobio) utilization of physical habitats that vary with flow in terms of size and type, persistence or duration, and frequency of change from one state to another, by comparing groundwater-dominated sites on the River Tern (Shropshire) with surface runoff-dominated lowland, riffle-pool sites on the Dowles Brook (Worcestershire). Mesohabitat surveys carried out at two-month intervals on a groundwater-dominated stream and on a surface runoff-influenced stream showed differences in habitat composition and diversity between the two types of rivers. The temporal variability in mesohabitat composition was also shown to differ between the two flow regime types. In the groundwater-influenced stream, mesohabitat composition hardly varied between flows whereas in the flashy stream it varied to a great extent with discharge. Habitat suitability curves for brown trout and bullhead were constructed to predict the potential location of the fish according to flow. The resulting prediction maps were tested in the field during fish surveys using direct underwater observation (snorkelling). Under the groundwater-influenced flow regime brown trout displayed a constant pattern of mesohabitat use over flows. Mesohabitats with non-varying characteristics over flows and with permanent features such as large woody debris, macrophytes or any feature providing shelter and food were favoured. Biological processes, such as hierarchy, life cycle and life stage appeared to play a key role in determining fish habitat use and to a greater extent than physical processes in these streams. Bullhead observations in the flashy river showed that mesohabitat use varied with flow but that some mesohabitats were always favoured in the stream. Pools and glides were the most commonly used mesohabitat, due to their stability over flows and their role as shelter from harsh hydraulic conditions and as food retention zones. The presence of cobbles was also found to be determinant in bullhead choice of habitat. In this flashy environment, physical processes such as flow and depth and velocity conditions appeared to be a more decisive factor in bullhead strategy of habitat use than biological processes. This research shows that: 1. Though differences in habitat use strategies between the two flow regimes can in part be attributed to differing ecology between the species, flow variability affects fish behaviour. 2. A stable flow regime allows biological processes to be the main driving force in determining fishbehaviour and location. A highly variable environment requires fish to develop behaviour strategies in response to variations in hydraulic conditions, such as depth and velocity, which constitute the key factor in determining fish location.

It is now well established that a wide range of natural and anthropogenic chemicals present in the aquatic environment have the potential to disrupt the endocrine system of many organisms. In fish, many of these effects appear to be of a feminising nature, including stimulation of vitellogenin production and induction of intersex. In piscivorous birds these so called endocrine disrupting contaminants have been shown to impair reproduction, influencing reproductive behaviour, sex ratio, eggshell thickness and reproductive success. The effects seen in fish have been associated with high levels of oestrogenic activity in the effluent from waste water treatments works (WwTWs), but few studies have focused on the effects of WwTWs effluents on birds. In this thesis, the effects of effluents from WwTWs on fish and birds were investigated in the Tamar catchment, SW England. The work spanned making detailed assessment on the oestrogenic and anti-androgenic activity of 3 WwTWs effluents, using a variety of water sampling techniques and applying both recombinant yeast oestrogen screen (YES) and recombinant yeast androgen screen (anti-YAS) bioassays to quantify the different hormonal activities. A survey was undertaken of the hormonal activities at 13 sites to determine concentrations of contaminants in the surface waters throughout the Tamar catchment, using both recombinant yeast screens and targeted analytical chemistry for specific pollutants (LC/MS-TOF and GCMS). An ELISA was developed to quantify vitellogenin (VTG) in the bullhead (our study fish sentinel) as a biomarker of oestrogen exposure, and evidence of endocrine disruption was investigated in wild populations of the bullhead, Cottus gobio and the dipper, Cinclus cinclus. Macroinvertebrates from upstream and downstream of three WwTW's effluent discharges and from three sampling sites were also sampled as an index of overall water quality in the Tamar catchment, and as an assessment of food availability for the bullheads and dippers. For the studies on the hormonal activities in three WwTWs in the Tamar catchment, samples were collected by both spot and passive sampling; passive samplers (in replicate) were placed in the effluent discharges for a three week period, and collected on days 7, 14 and 21, spot samples were taken simultaneously. Measurement of total oestrogenic and total anti-androgenic activity was conducted using the YES and anti-YAS, respectively. Spot and passive samples were collected from 13 sites within the Tamar catchment (sampling sites were >2 km downstream of effluent discharges). Additionally, liquid chromatography mass spectrometry time-of-flight (LC/MS-TOF) was used to measure the concentration of oestrone (E1), 17β-oestrodiol (E2) and 17α-ethinylestradiol (EE2) in each sample. Gas chromatography mass spectrometry (GCMS) was used to measure the concentration of individual PBDE and PCB congeners in the spot samples only. Levels of oestrogenic and anti-androgenic activity observed in the WwTWs effluent were comparable with those measured in effluents in the UK and in other countries. Surface waters of the Tamar, away from the WwTWs effluent discharges, contained very little oestrogenic activity (<1.1 ng E2 EQs L-1), and anti-androgenic activity was undetectable. Quantification of oestrogenic activity using passive samplers showed an increasing amount of total oestrogenic activity between days 7 and 21 when measured by the both the YES and LC/MS-TOF. Low levels of PBDE congeners 47, 99, 100, 138 and 153 were detected in the spot samples taken from the Tamar catchment, with BDE 47 being the most abundant. In contrast PCBs were undetectable. Neither PBDEs nor PCBs were detected in any of the extracts from the passive samples. No assay was available to measure VTG (one of the most widely used biomarkers of oestrogen exposure in fish) in the bullhead and so an enzyme linked immunosorbant assay (ELISA) was developed for application to studies on wild bullheads in the Tamar catchment. The bullhead vitellogenin (bh-VTG) ELISA was developed successfully, and proved to be sensitive and robust, with a detection range between 10.5 and 300 ng bh-VTG mL-1 (undiluted), comparing favourably with other fish VTG ELISAs. Plasma VTG concentrations measured in male bullheads (collected from the same sites as for the water samples) ranged from below the limit of detection to 990 ng bh-VTG mL-1. Whether these upper levels in the range reflected VTG induction was difficult to conclude. Because of this controlled caged exposures with bullheads and trout were used to assess the relative levels of oestrogenicity in two key WwTWs effluent discharges and to determine the response sensitivity of the bullheads (and trout) to those effluents. These controlled exposures found no responses in plasma VTG in bullheads (ranging between 126 and 934 ng bh-VTG mL-1) suggesting a lack of sensitivity for VTG induction. This was supported by the inability to induce VTG in fish held in the laboratory and treated with steroidal oestrogens. For the effluent exposures on the caged rainbow trout, it was also found that there was no significant induction of VTG, a species normally sensitive to oestrogens. These findings may indicate that the fish were highly stressed due to the river being in spate and the movement of the cages during the controlled exposures. It may also be the case, however, that the use of immature female rainbow trout with a highly variable baseline plasma VTG concentration may prevent any detection of a response. There were no signs of sexual disruption in any of the gonads analysed from either male or female wild bullheads, demonstrating that any hormonal activity present in the catchment away from the WwTWs effluents was not sufficient to induce adverse effects on reproductive development. An interesting feature noted in the male testes of the bullheads was the presence of spermatid masses, which have been recorded in 10 other Cottidae species, but not previously in the bullhead. For the studies on dippers, eggs were collected from the nests of breeding dippers to measure for sperm numbers and morphology from sperm trapped in the perivitelline membrane (PVM), and the yolks were analysed for PBDEs, PCBs and organochlorine pesticides (OCPs) by GCMS, for E1, E2, and EE2 by LC/MS-TOF. Eggs of the dipper were collected from nests at the 13 sampling sites, plus an additional three sites and over three years of field study. The number of sperm trapped in the PVM ranged between three and 188, with a mean of 68.78 ± 8.78 SE. Dipper sperm had not previously been characterised, and was found to be similar to other passerine sperm, in that the head was helical, complemented by a mitochondrial helix or keel, which continued in a spiral around the flagellum. Sperm were classed as ‘abnormal’ if they did not adhere to this typical structure. No assessment of motility could be made in relation to the structural abnormalities seen. Contaminants in the dipper eggs were dominated by BDE 99, an unusual result considering the dippers aquatic lifestyle. PCB 153 was the most common PCB, and p,p’-DDE was the most abundant OCP; all other pesticides tested were below the limit of detection, as were the levels of all three steroid oestrogens. There was inter- and intra-nest variability between contaminant burdens in all eggs as well as the number of sperm trapped in the PVM, but there was no relationship between sperm number and the level of contaminant loadings in the eggs. There were no correlations between contaminants and oestrogenic activity measured in the water samples, and plasma VTG concentrations in bullheads or contaminant loadings in eggs, or indeed sperm number. Analysis of macroinvertebrate assemblages proved that the surface waters of the Tamar catchment were of ‘very good’ quality, even in close proximity to WwTWs effluent discharges.

L'augmentation de la température des eaux continentales suite à un réchauffement climatique provoquera probablement des changements de traits d'histoire de vie et de distribution géographique des poissons dulçaquicoles. Dans cette étude, l'hypothèse d'un lien entre les traits d'histoire de vie et les variables environnementales (et plus particulièrement la température) a été testée grâce à des comparaisons inter-sites à l'intérieur d'une population de chabots (Cottus gobio, espèce benthique colonisant préférentiellement des eaux froides) présentant une structuration spatiale marquée. Nos résultats démontrent qu'une augmentation modérée de température (3 degrés, ce qui correspond aux changements thermiques prédits par les scénarii IPCC) sur des populations de chabots spatialement structurées affecteraient fortement leurs traits d'histoire de vie, leur structure en âges et leur densité. Des suivis à long terme sur le terrain ainsi que des études expérimentales complémentaires sont toutefois nécessaires pour confirmer ces conclusions

Bullhead is common fish of our trout zones of streams and small rivers. It lives in mountain streams or small rivers. It needs clear water with high oxygen saturation. Therefor bullhead is used as a bioindicatorof clear waters. The aim of our experiment was compare the influence of artificial and natural flood on bullhead population in river Labe. Artificial flood was caused by wild water race competition in 2011. There was drained the water reservoir Labská during this event. The observed stretch of river Labe was fished out before and after this competition using electric generator. The fish obtained before the artificial flood were branded and released back to the river. New out fishing was done immediately after the flood. There were counted and measured the fish with or without brands. The same manner was used for obtaining of dates before and after natural flood in 2012. The main result of this experiment is showing the artificial flood is more destructive and dangerous than natural flood. The reason is faster increase and decrease of flow in river during the artificial flood.

<em>Abstract</em>.—The pumpkinseed <em>Lepomis gibbosus </em>was introduced to Europe, including England, more than 100 years ago, but relatively little is known of its potential ecological impacts on native species and ecosystems. In England, the pumpkinseed is currently established in ponds of the River Ouse (Sussex) and its flood plain. Escapee pumpkinseeds are found in some small tributaries that contain native species of conservation interest (brown trout <em>Salmo trutta</em>, brook lamprey <em>Lampetra planeri</em>, European eel <em>Anguilla anguilla</em>, European bullhead <em>Cottus gobio</em>). We used using electrofishing surveys and telemetry methods to examine the interactions between pumpkinseeds and native stream fishes (mainly brown trout), including predator–prey relationships, home range size, microhabitat preferences, home range fidelity, and habitat overlap/repartition. To assess impacts of pumpkinseed on stream food webs, a preliminary study quantified trout growth and food-web structure of a stream ecosystem (abundance of primary and secondary producers, fish, and riparian spiders) in reaches with and without pumpkinseed. Where pumpkinseeds were in high density, differences were observed in stream food-web structure, in proportional representation of fish species traits and in riparian spider community composition, but these differences cannot be attributed solely to pumpkinseed presence. From the available evidence, there appears to be little direct or indirect adverse impact of pumpkinseed on native species and the stream ecosystem when in low densities, including as a host of nonnative infectious agents. However, this could change under conditions of climate warming, which are likely to favor pumpkinseed reproduction, potentially to the detriment of native species. In a context in which freshwater ecosystems are impacted by several human and climate-induced factors acting synergistically, our results underline the need to study nonnative species impacts through a series of experimental and long-term studies of stream ecosystems.

The aim of the study was to determine the prevalence of Cottus poecilopus in the main streams of the Tatra National Park in Poland. Fishing research was conducted within the summer and in the autumn of 2014 for fourteen streams. The catches were made with pulse fishing device (IUP-24) wading up stream. During fishing caught fishes have been characterized and habitat has been characterized by noting the speed of the current, the presence of obstacles and hiding places for fish, width, type and size of the bottom substrate, the presence of wood and shade. The beginning and end of each transect was described by the geographic coordinates using a Garmin GPS device. Based on the geographical coordinates the project was created in GIS (using ArcMap software 9.3.1) and determined the amount of occurrence of fish above sea level. In the course of fishing three species of fish were found: Cottus poecilopus, Salmo trutta m. fario and Salvelinus fontinalis. In the studied streams Cottus gobio was not found. The most numerous Cottus poecilopus were represented, a total of 485 individuals in 12 streams. Stream Chochołowski Potok (1077.3 m above sea level) was the highest position where the genre occured.