| telemetry-determined habitat use informs multi-species habitat management in an urban harbour. | widespread human development has led to impairment of freshwater coastal wetlands and embayments, which provide critical and unique habitat for many freshwater fish species. this is particularly evident in the laurentian great lakes, where such habitats have been severely altered over the last century as a result of industrial activities, urbanization, dredging and infilling. in toronto harbour, extensive restoration efforts have been directed towards improving the amount and quality of aquatic ... | 2017 | 27744518 |
| comparative movements of four large fish species in a lowland river. | a multi-year radio-telemetry data set was used to comparatively examine the concurrent movements of the adults of three large-bodied australian native freshwater fishes (murray cod maccullochella peelii, trout cod maccullochella macquariensis and golden perch macquaria ambigua) and the introduced carp cyprinus carpio. the study was conducted over a reach scale in the regulated murray river in south-eastern australia. differences were identified in the movements among these species. the predomina ... | 2016 | 26919062 |
| interactions between water temperature and contaminant toxicity to freshwater fish. | warming of freshwaters as a result of climate change is expected to have complex interactions with the toxicity of contaminants to aquatic organisms. the present study evaluated the effects of temperature on the acute toxicity of endosulfan, chlorpyrifos, and phenol to 3 warm water species of fish-silver perch, rainbowfish, and western carp gudgeon-and 1 cold water species, rainbow trout. endosulfan was more toxic to silver perch at 30 °c and 35 °c than at 15 °c, 20 °c and 25 °c during short exp ... | 2015 | 26033197 |
| ontogeny of critical and prolonged swimming performance for the larvae of six australian freshwater fish species. | critical (<30 min) and prolonged (>60 min) swimming speeds in laboratory chambers were determined for larvae of six species of australian freshwater fishes: trout cod maccullochella macquariensis, murray cod maccullochella peelii, golden perch macquaria ambigua, silver perch bidyanus bidyanus, carp gudgeon hypseleotris spp. and murray river rainbowfish melanotaenia fluviatilis. developmental stage (preflexion, flexion, postflexion and metalarva) better explained swimming ability than did length, ... | 2014 | 24814314 |
| coping with continual danger: assessing alertness to visual disturbances in crucian carp following long-term exposure to chemical alarm signals. | chemical alarm signals in fish are passively released into the water from ruptured epidermal cells, and induce instant fright responses in conspecifics. fish also display alarm responses to injured heterospecific skin, as well as to scent of piscivorous predators that have ingested prey. a conspicuous alertness to visual disturbances has also been observed in fish following long-term exposure to extracts of filtered, homogenized skin, but the chemical inducers of such vigilance are actually unkn ... | 2014 | 24398068 |
| accumulation and half-lives of 13 pesticides in muscle tissue of freshwater fishes through food exposure. | fish are often exposed to various molecules like pesticides. some of these compounds get biomagnified within aquatic food web, inducing health hazards of consumers. however, behaviors of many pesticides are still unknown. this work aims to study the uptake and the elimination of some of them in muscle tissue of edible fish (azoxystrobin, clomazone, diflufenican, dimethachlor, carbendazim, iprodion, isoproturon, mesosulfuron-methyl, metazachlor, napropamid, quizalofop, and thifensulfuron-methyl). ... | 2013 | 23374295 |
| pesticide pressure and fish farming in barrage pond in northeastern france. part ii: residues of 13 pesticides in water, sediments, edible fish and their relationships. | residues of pesticides in fish farming productions from barrage ponds are seldom studied in spite of increasing health questionings and environmental concerns. the purpose of this study is to establish the pesticide contamination profiles of sediments and edible fish from five ponds in northeastern france. multi-residues method and liquid chromatography-tandem mass spectrometry analysis were used to quantify 13 pesticides (azoxystrobin, carbendazim, clomazone, diflufenican, dimethachlor, fluroxy ... | 2013 | 22961490 |
| emergence of epizootic ulcerative syndrome in native fish of the murray-darling river system, australia: hosts, distribution and possible vectors. | epizootic ulcerative syndrome (eus) is a fish disease of international significance and reportable to the office international des epizootics. in june 2010, bony herring nematalosa erebi, golden perch macquaria ambigua, murray cod maccullochella peelii and spangled perch leiopotherapon unicolor with severe ulcers were sampled from the murray-darling river system (mdrs) between bourke and brewarrina, new south wales australia. histopathology and polymerase chain reaction identified the fungus-lik ... | 2012 | 22558170 |
| pesticide pressure and fish farming in barrage pond in northeastern france. part iii: how management can affect pesticide profiles in edible fish? | the quality of fish produced in ponds needs to be ensured. indeed, pond is often strongly connected to an agricultural watershed, and pesticides are a main health and environmental issue of concern. in this context, the purpose of this study is to highlight the management practices which could impact the pesticide contamination profiles in edible fish and to give recommendations for better practices. | 2013 | 22467231 |
| sensory and textural attributes and fatty acid profiles of fillets of extensively and intensively farmed eurasian perch (percafluviatilis l.). | sensory attributes, texture and fatty acid profiles of fillets of eurasian perch (percafluviatilis l.) reared under two conditions were compared. perch were reared either in an extensive pond-based (ec) system in polyculture with carp, or intensively cultured (ic) in a recirculation system. attributes of raw and cooked fillets of marketable perch (120-150g) were compared. no significant differences were found between groups for odour, flavour, aftertaste, or consistency in subjective evaluation ... | 2011 | 25212336 |
| organochlorine pesticides and polychlorinated biphenyls in sediments and fish from freshwater cultured fish ponds in different agricultural contexts in north-eastern france. | organochlorine pesticides (hcb, hch with α-, β-, and γ isomers, heptachlor, cis-heptachlor epoxyde, trans-heptachlor epoxyde, endosulfan with α- and β isomers, sulfate endosulfan, o,p'-ddt, p,p'-ddt, o,p'-dde, p,p'-dde, o,p'-ddd, p,p'-ddd, chlorothalonil, alachlor, aldrin, dieldrin, methoxychlor, oxychlordane, chlordane with α- and γ isomers, p,p'-dicofol and o,p'-dicofol) and indicators pcbs (iupac nos. 28, 52, 101, 118, 138, 153, and 180) were studied both in sediments and muscles of farmed fi ... | 2012 | 22071217 |
| detection of temporal trends of α- and γ-chlordane in lake erie fish communities using dynamic linear modeling. | dynamic linear modeling (dlm) analysis was performed to identify the long-term temporal trends of two toxic components of the technical chlordane pesticide, α- and γ-chlordane, in skinless-boneless muscle tissues of a number of sport fish species in lake erie. our analysis considers the fish length as a covariate of the chlordane concentrations. the α-chlordane models for the coho salmon, channel catfish, rainbow trout, and common carp showed continuously decreasing trends during the entire 30+ ... | 2011 | 21536330 |
| multiresidue method to quantify pesticides in fish muscle by quechers-based extraction and lc-ms/ms. | pesticide residues in fish muscle are an environmental and a health safety concern which requires analytical methods presenting high sensitivity and low limits of quantification. in this study, adapted quechers method, coupled to liquid chromatography tandem mass spectrometry (scheduled mrm-5500 qtrap), was developed to quantify 13 pesticides (azoxystrobin, clomazone, diflufenican, dimethachlor, carbendazim, iprodion, isoproturon, mesosulfuron-methyl, metazachlor, napropamid, quizalofop and thif ... | 2011 | 21484246 |
| calcitonin-like immunoreactivity in the subcommissural organ-reissner's fiber complex of some freshwater and marine teleosts. | the subcommissural organ (sco) is a highly specialised circumventricular ependymal organ covering and penetrating the posterior commissure. the secretory products of the sco condense to form reissner's fiber (rf). because of its extensive secretory activity and the chemical properties of its secretion, the organ functions as similar to the neurosecretory cells. teleosts comprised of more than 20,000 extant species that show great diversity in terms of the form, habit and habitat. affinity of cal ... | 2011 | 21184824 |
| effects of anesthesia and surgery on serial blood gas values and lactate concentrations in yellow perch (perca flavescens), walleye pike (sander vitreus), and koi (cyprinus carpio). | objective-to evaluate serial blood gas values and lactate concentrations in 3 fish species undergoing surgery and to compare blood lactate concentrations between fish that survived and those that died during the short-term postoperative period. design-prospective cohort study. animals-10 yellow perch, 5 walleye pike, and 8 koi. procedures-blood samples were collected from each fish at 3 time points: before anesthesia, during anesthesia, and immediately after surgery. blood gas values and blood l ... | 2010 | 20470073 |
| temporal and geographic trends in mercury concentrations in muscle tissue in five species of hudson river, usa, fish. | we analyzed a new york (usa) state database of mercury concentrations in muscle tissue for five species of fish (striped bass, yellow perch, largemouth bass, smallmouth bass, and carp) over a range of locations in the hudson river (usa) between 1970 and 2004. we used regression models to discern temporal and geographic change in the fish while controlling for a positive correlation between mercury concentration and body mass. mercury concentrations significantly increased in fish from new york h ... | 2008 | 18266478 |
| contaminants in fish of the hackensack meadowlands, new jersey: size, sex, and seasonal relationships as related to health risks. | the trace metal content and related safety (health risk) of hackensack river fish were assessed within the hackensack meadowlands of new jersey, usa. eight elements were analyzed in the edible portion (i.e., muscle) of species commonly taken by anglers in the area. the white perch collection (morone americana) was large enough (n = 168) to enable statistically significant inferences, but there were too few brown bullheads and carp to reach definite conclusions. of the eight elements analyzed, th ... | 2007 | 17106790 |
| are hearing sensitivities of freshwater fish adapted to the ambient noise in their habitats? | several groups of fishes, among them two thirds of all freshwater fishes, have developed hearing specializations that enhance auditory sensitivity and broaden frequency ranges compared with hearing non-specialists (generalists), which lack such adaptations. it has been speculated that the enhanced sensitivities of these so-called hearing specialists have evolved in quiet habitats such as lakes, backwaters of rivers, slowly flowing streams or the deep sea. to test this hypothesis, noise levels an ... | 2005 | 16155225 |
| noise emission during the first powerboat race in an alpine lake and potential impact on fish communities. | in order to assess the effects of high-speed boating on fish communities, noise levels were measured during the first class 1 powerboat race on the austrian lake traunsee. the noise spectra were compared to natural ambient noise and hearing abilities of four native fish species. sound pressure levels (spls) were significantly elevated during the training heats and the race compared with natural levels, reaching up to 128 db re 1 micropa (instantaneous spl) at a distance of 300 m to the powerboat ... | 2004 | 15658729 |
| vitellogenin in carp (cyprinus carpio) and perch (perca fluviatilis): purification, characterization and development of an elisa for the detection of estrogenic effects. | vitellogenin (vtg), a phospholipoglycoprotein precursor of egg yolk is synthesized and secreted in the liver in response to circulating estrogens in female fish. thus, the presence of vtg in male fish is a useful biomarker to identify estrogenic activity of natural or anthropogenic substances in sewage effluents. we report the purification of carp (cyprinus carpio) and perch (perca fluviatilis) vtg with the subsequent development and characterization of a specific elisa for vtg measurement. vtg ... | 2003 | 12798095 |
| the influence of spatial scale and habitat arrangement on diel patterns of habitat use by two lowland river fishes. | there is growing awareness that patterns of habitat use by animals cannot be isolated from issues of scale. recently, techniques have been devised which allow empirical testing of hypotheses related to the effects of spatial scale on habitat use. we used spatially explicit statistical procedures to examine the roles of scale and habitat arrangement in determining fish distribution patterns in a reach of an australian lowland river. native golden perch and introduced common carp were tracked day ... | 2001 | 24577692 |
| parvalbumin, a cross-reactive fish allergen, contains ige-binding epitopes sensitive to periodate treatment and ca2+ depletion. | type i allergy to fish is a severe health problem in countries in which a large percentage of the population derive income from fishing. | 1998 | 9449503 |
| organochlorine pesticides and polychlorinated biphenyl congeners in commercial fish from the great lakes. | fillets from 11 species of commercial fish from the great lakes were analyzed for residues of 39 polychlorinated biphenyl (pcb) congeners and 24 other organochlorine compounds. eel and trout contained the highest amount of pcb (753 and 633 ppb wet weight, respectively) and other organochlorines (607 and 1404 ppb, respectively); perch and carp contained the lowest residues. the penta- and hexachlorinated pcbs were the major congeners in all species except whitefish, in which the tetrachlorinated ... | 2013 | 8374320 |
| a monoclonal antibody specific to müller cells and selective synaptic sites in the retina. | we have produced a monoclonal antibody which stains the müller cells in the region of the photoreceptors, nerve terminals surrounding the horizontal cells, and nerve terminals in the inner plexiform layer in carp, goldfish, and white perch retinas. electron microscopy showed that the staining in the outer and inner retina was confined to müller cells and presynaptic terminals, respectively. in the teleost brain, the antibody stained only the optic tectum and efferent fibers from the stratum albu ... | 1990 | 1692309 |
| modulation of cone horizontal cell activity in the teleost fish retina. i. effects of prolonged darkness and background illumination on light responsiveness. | the effects of prolonged (greater than 2 hr) darkness and background illumination on the light responsiveness of cone horizontal cells were examined in isolated, superfused white perch retinas. in retinas from fish maintained in complete darkness for more than 2 hr, cone horizontal cells had a resting membrane potential of about -18 mv, and they generated only slow, low-amplitude (3-4 mv) responses even when stimulated with bright flashes. following the presentation of dim background light, the ... | 1988 | 3249224 |
| the in vitro metabolism of eulan wa new by liver homogenates from freshwater fish. | the rate of formation of pentachloro-2-aminodiphenylether (5-pad) from pentachloro-2-(chloromethylsulphonamido) diphenylether (6-pcsd) by goldfish liver homogenates was studied in a variety of buffers. the highest rate was observed when the homogenate was prepared and assayed in phosphate buffer containing dithiothreitol. the 5-pad forming activity of liver homogenate preparations from a variety of freshwater fish (goldfish, carp, pike, rainbow trout, perch and eel) showed contrasting species di ... | 1986 | 2873942 |
| a comparison of quantitative ultrastructural and contractile characteristics of muscle fibre types of the perch, perca fluviatilis l. | quantitative ultrastructural and physiological parameters were investigated in three types of muscle fibres of perca fluviatilis: white fibres from the m. levator operculi anterior, pink (intermediate) fibres of the m. hyohyoideus and deep red fibres of the m. levator operculi anterior. times to peak tension and half relaxation times of isometric twitches increased in the mentioned order. the extent of contact between the t system and the sarcoplasmic reticulum and the relative volume and surfac ... | 1985 | 3837036 |
| evidence for somatostatin, gastrin and pancreatic polypeptide-like substances in the mucosa cells of the gut in fishes with and without stomach. | gastrin, pancreatic polypeptide and somatostatin immunoreactive cells in the gut of two fish with stomachs (perch and catfish) and a stomachless fish (carp) were studied by immunocytochemistry. in the gastric mucosa of perch and catfish, cells showing gastrin and somatostatin-like immunoreactivity are found, scattered among the surface mucous cells and mucous neck cells. no pancreatic polypeptide (p.p.) immunoreactive cells are detected in the gastric mucosa. cells showing gastrin and p.p.-like ... | 1981 | 6112066 |
| molecular cloning and expression analysis of the myostatin gene in sea perch (lateolabrax japonicus). | myostatin (mstn) is a member of the transforming growth factor-beta (tgf-beta) superfamily that functions as a negative regulator of skeletal muscle development and growth in mammals. however, few reports are available about the structure and function of mstn in teleost. here, the mstn gene was cloned from sea perch (lateolabrax japonicus) by homology cloning and genomic walking. in the 4873-bp genomic sequence, three exons, two introns, and 5' and 3' flanking sequences were identified. the sea ... | 2008 | 17308997 |
| sex steroids in the female zebrafish (danio rerio). effects of cyproterone acetate and leachate-contaminated sediment extract. | in molnbyggen, a leachate-contaminated lake in sweden, effects on the reproductive system of perch included a decreased frequency of sexually mature female perch, reduced gonadosomatic index and decreased plasma levels of androstenedione and testosterone, but the contaminants responsible for these effects have not yet been identified. a biomarker-directed fractionation approach could be used to narrow the search for the compound(s) responsible for the adverse effects in molnbyggen female perch. ... | 2006 | 16844241 |
| numerical bifurcation analysis of physiologically structured populations: consumer-resource, cannibalistic and trophic models. | with the aim of applying numerical methods, we develop a formalism for physiologically structured population models in a new generality that includes consumer-resource, cannibalism and trophic models. the dynamics at the population level are formulated as a system of volterra functional equations coupled to ode. for this general class, we develop numerical methods to continue equilibria with respect to a parameter, detect transcritical and saddle-node bifurcations and compute curves in parameter ... | 2016 | 27484496 |
| optimal foraging: the difficulty of exploiting different feeding strategies simultaneously. | the foraging efficiency of a visually feeding fish, perch (perca fluviatilis) was studied on two prey species (daphnia magna and chaoborus obscuripus) presented either separately or combined. it is shown that when both prey species are present, the foraging efficiency of the predator is reduced. this is due to the predator's inability to simultaneously cope with prey species with different anti-predatory behaviour. in the mixed-meal experiment the predator captured both prey species in equal pro ... | 1985 | 28311566 |
| strike fast, strike hard: the red-throated caracara exploits absconding behavior of social wasps during nest predation. | red-throated caracaras ibycter americanus (falconidae) are specialist predators of social wasps in the neotropics. it had been proposed that these caracaras possess chemical repellents that allow them to take the brood of wasp nests without being attacked by worker wasps. to determine how caracaras exploit nests of social wasps and whether chemical repellents facilitate predation, we: (1) video recorded the birds attacking wasp nests; (2) analyzed surface extracts of the birds' faces, feet, and ... | 2013 | 24386338 |
| multiple vitellogenins and product yolk proteins in european sea bass (dicentrarchus labrax): molecular characterization, quantification in plasma, liver and ovary, and maturational proteolysis. | three complete vitellogenin (vtg) polypeptides of european sea bass (dicentrarchus labrax), an acanthomorph teleost spawning pelagic eggs in seawater, were deduced from cdna and identified as vtgaa, vtgab and vtgc based on current vtg nomenclature and phylogeny. label free quantitative mass spectrometry verified the presence of the three sea bass vtgs or their product yolk proteins (yps) in liver, plasma and ovary of postvitellogenic females. as evidenced by normalized spectral counts, vtgab-der ... | 2016 | 26643259 |
| a phylogeny of the temperate seabasses (moronidae) characterized by a translocation of the mt-nd6 gene. | the entire mitochondrial genome of the striped bass morone saxatilis was sequenced together with the mitochondrial (mt) control regions of the white bass morone chrysops, white perch morone americana, yellow bass morone mississippiensis, spotted seabass dicentrarchus punctatus, european seabass dicentrarchus labrax and the japanese seabass lateolabrax japonicus. the resultant 17 580 base pair circular genome of m. saxatilis contains 38 genes (13 proteins, 23 transfer rnas and two ribosomal rnas) ... | 2012 | 22220893 |
| [demonstration of natural killer cells (nk) in the breeding perch (dicentrarchus labrax). effect of breeding temperature]. | | 1983 | 6825421 |
| [the rodlet cells of some species of freshwater and marine bony fishes of orders cypriniformes and perciformes]. | the fine structure of rodlet cells from pronephros of cobitis taenia (l.), mesonephros of tinca tinca (l.), rutilus rutilus (l.), stizostedion volgense (gmelin), stizostedion lucioperca (l.), perca fluviatilis (l.), trachurus mediterraneus (staindachner) and diplodus annularis (l.) was studied. in the organs examined, cells at developmental stages iii, iv and v were detected. it is shown, that the rodlet cells have the structural organization similar to that described in different organs of fish ... | 2011 | 21539089 |
| pathogens trigger top-down climate forcing on ecosystem dynamics. | evaluating the effects of climate variation on ecosystems is of paramount importance for our ability to forecast and mitigate the consequences of global change. however, the ways in which complex food webs respond to climate variations remain poorly understood. here, we use long-term time series to investigate the effects of temperature variation on the intraguild-predation (igp) system of windermere (uk), a lake where pike (esox lucius, top predator) feed on small-sized perch (perca fluviatilis ... | 2016 | 26910776 |
| description of the microsporidian parasite, heterosporis sutherlandae n. sp., infecting fish in the great lakes region, usa. | heterosporosis is an increasingly important microsporidian disease worldwide, impacting wild and farmed raised fishes in both marine and freshwater environments. a previously undescribed species (heterosporis sp.), with widespread distribution in the great lakes region, was the subject of this study. three angler-caught fish were submitted to the minnesota veterinary diagnostic laboratory from 2009-2010 with lesions caused by intracellular proliferation of parasitic spores, resulting in destruct ... | 2015 | 26244983 |
| high prevalence of trypanosome co-infections in freshwater fishes. | one thousand three hundred seventy three fish specimens of eight different species from the vicinity of kyiv, ukraine, were examined for the presence of trypanosomes and 921 individuals were found to be infected. the prevalence of infection ranged from 24% in freshwater bream, abramis brama (linnaeus), to 100% in spined loach, cobitis 'taenia' linnaeus. the level of parasitaemia also varied significantly between generally mild infections in pikeperch, sander lucioperca (linnaeus), and heavy ones ... | 2014 | 25651690 |
| spatio-temporal trends of pcbs in the swedish freshwater environment 1981-2012. | polychlorinated biphenyls (pcbs) have been monitored in perch (perca fluviatilis), pike (esox lucius), and arctic char (salvelinus alpinus) in reference lakes since the late 1960s. temporal trends and spatial patterns are currently monitored in nine and 32 lakes, respectively. overall, pcb concentrations are decreasing. however, this is not consistent for all congeners across all lakes and species. perch has comparatively low pcb concentrations relative to suggested target levels, but individual ... | 2014 | 25403969 |
| shoreline development and degradation of coastal fish reproduction habitats. | coastal development has severely affected habitats and biodiversity during the last century, but quantitative estimates of the impacts are usually lacking. we utilize predictive habitat modeling and mapping of human pressures to estimate the cumulative long-term effects of coastal development in relation to fish habitats. based on aerial photographs since the 1960s, shoreline development rates were estimated in the stockholm archipelago in the baltic sea. by combining shoreline development rates ... | 2014 | 24943864 |
| effect of boat noise and angling on lake fish behaviour. | the effects of disturbances from recreational activities on the swimming speed and habitat use of roach rutilus rutilus, perch perca fluviatilis and pike esox lucius were explored. disturbances were applied for 4 h as (1) boating in short intervals with a small outboard internal combustion engine or (2) boating in short intervals combined with angling with artificial lures between engine runs. the response of the fish species was evaluated by high-resolution tracking using an automatic acoustic ... | 2014 | 24813930 |
| feeding efficiency of planktivores under disturbance, the effect of water colour, predation threat and shoal composition. | the consumption of phantom midge chaoborus flavicans larvae by perca fluviatilis showed clear response to water colour, predation threat and shoal composition with the most significant negative effect for water colour. in the case of rutilus rutilus, no similar combined response was observed and the total prey consumption was significantly negatively affected by predation threat of esox lucius. the results suggest that differences in life-history traits may result in disparity in species-specifi ... | 2014 | 24689675 |
| can natural variability trigger effects on fish and fish habitat as defined in environment canada's metal mining environmental effects monitoring program? | the metal mining effluent regulations (mmer) took effect in 2002 and require most metal mining operations in canada to complete environmental effects monitoring (eem) programs. an "effect" under the mmer eem program is considered any positive or negative statistically significant difference in fish population, fish usability, or benthic invertebrate community eem-defined endpoints. two consecutive studies with the same statistically significant differences trigger more intensive monitoring, incl ... | 2013 | 22888037 |
| short- and long-term patterns of ¹³⁷cs in fish and other aquatic organisms of small forest lakes in southern finland since the chernobyl accident. | we summarize the patterns of ¹³⁷cs activity concentrations and transfer into fish and other biota in four small forest lakes in southern finland during a twenty-year period following the chernobyl accident in april 1986. the results from summer 1986 showed fastest accumulation of ¹³⁷cs into planktivorous fishes, i.e. along the shortest food chains. since 1987, the highest annual mean values of ¹³⁷cs have been recorded in fish occupying the highest trophic levels, for perch (perca fluviatilis) 13 ... | 2012 | 22036157 |
| the interactions of abiotic and biotic factors influencing perch perca fluviatilis and roach rutilus rutilus populations in small acidified boreal lakes. | four small, acidified boreal lakes, all sustaining populations of perch perca fluviatilis, roach rutilus rutilus and pike esox lucius, were studied in four successive years. three lakes were moderately acidified (mean ph of 5·61-5·83), while the fourth was more acidic (mean ph of 5·16) and had a sparse population of r. rutilus. perca fluviatilis density was higher in this lake (1004 ha(-1)) than in the other three (355-717 ha(-1)), where r. rutilus dominated in terms of numbers (981-2185 ha(-1)) ... | 2011 | 21781101 |
| the dependence on temperature and ph of the effects of zinc and copper on proteolytic activities of the digestive tract mucosa in piscivorous fish and their potential preys. | the dependence of the effects of zinc and copper on the activities of proteinases of the stomach and intestinal mucosa on temperature and ph in four species of boreal piscivorous fish (pike esox lucius, zander zander lucioperca, perch perca fluviatilis and burbot lota lota) as well as in some of their potential preys (kilka clupeonella cultriventris, ruff gymnocephalus cernuus, perch and roach rutilus rutilus) was investigated. species-specific differences of the effects of these heavy metals up ... | 2010 | 19731060 |
| investigation of first year biotic and abiotic influences on the recruitment of pike esox lucius over 48 years in windermere, uk. | estimated pike esox lucius recruitment varied by a factor of 16 for females from 1944 to 1991 and by a factor of 27 for males from 1943 to 1990 in windermere, a temperate, mesotrophic u.k. lake. no significant stock-recruitment relationships were found, but analysis with general additive models (gams) revealed that early autumnal water temperature, strength and direction of the north atlantic oscillation displacement (corresponding to different climatic conditions in winter) and zooplankton abun ... | 2009 | 20735553 |
| bioaccumulation of organochlorine pollutants in the fish community in lake arungen, norway. | organochlorine pollutants in the major fish species (pike esox lucius, perch perca fluviatilis, and roach rutilus rutilus) of lake arungen, norway, were investigated after an extensive removal of large pike in 2004. the organochlorine pollutants detected in fish liver samples in 2005 were dichlorodiphenyltrichloroethane (ddts), polychlorinated biphenyls (pcbs), hexachlorobenzene (hcb), and heptachlor epoxide (hce). ddts were the dominant among all analyzed ocs. sigma pcb and hcb, detected in fis ... | 2013 | 19329237 |
| antagonistic selection from predators and pathogens alters food-web structure. | selection can alter predator-prey interactions. however, whether and how complex food-webs respond to selection remain largely unknown. we show in the field that antagonistic selection from predators and pathogens on prey body-size can be a primary driver of food-web functioning. in windermere, u.k., pike (esox lucius, the predator) selected against small perch (perca fluviatilis, the prey), while a perch-specific pathogen selected against large perch. the strongest selective force drove perch t ... | 2008 | 19064927 |
| dredging associated effects: maternally transferred pollutants and dna adducts in feral fish. | this study reports on the bioavailability, maternal transfer, and genotoxicity in feral fish of organic sediment pollutants. northern pike (esox lucius) and perch (perca fluviatilis) were caught in a polluted bay before and during dredging activities and from reference areas. polychlorinated biphenyls (pcbs) and polycyclic aromatic hydrocarbons (pahs) were analyzed in ovulating eggs to investigate if the bay sediment posed a threat to early life-stages of fish. on the basis of previous investiga ... | 2007 | 17533866 |
| state-dependent invasion windows for prey in size-structured predator-prey systems: whole lake experiments. | 1. in size-structured communities where individuals grow in size over their life cycle, interactions between species will shift between competitive and predatory interactions depending on size relationships. the outcome of interactions will subsequently depend on the strength of competitive and predatory interactions, respectively. 2. in a whole lake experiment including four experimental lakes, it was tested under which conditions the competing prey, roach rutilus rutilus, could successfully re ... | 2007 | 17184357 |
| biomagnification of polychlorinated biphenyls (pcbs) and polybrominated diphenyl ethers (pbdes) studied in pike (esox lucius), perch (perca fluviatilis) and roach (rutilus rutilus) from the baltic sea. | pike, perch and roach from rural waters of the baltic sea were investigated for possible biomagnification of polychlorinated biphenyls (pcbs) and polybrominated diphenyl ethers (pbdes). for this we used data on delta15n, weight and sex of the fish. we were able to separate body size effects from trophic position effects on biomagnification. both these parameters lead to biomagnification of pcbs and pbdes. all investigated pcbs (tri- to deca-cbs) biomagnify and the biomagnification potential is p ... | 2004 | 15051373 |
| size-dependent foraging efficiency, cannibalism and zooplankton community structure. | to examine size-dependent food web interactions in systems with cannibalism, we compared the abundances of zooplankton and phytoplankton over 2 years in four lakes with cannibalistic perch (perca fluviatilis) of which two also supported the top predator pike (esox lucius). the abundance of perch 2 years and older was lower in lakes with pike than in lakes with only perch. in contrast, the abundance of small perch (young-of-the-year and 1-year old) was lower in lakes with only perch suggesting th ... | 2000 | 28308739 |
| [assessment of pathological changes in fish muscle tissue, forming as a result of exposure to toxic factors in the environment]. | our investigation of muscle tissue of fishes, inhabiting the regions with unfavorable ecological conditions (the river volga), permitted to select four types of degenerative changes in muscle tissue. these alterations are associated with both the phylogenetic status of fish species and ecological dispositions of species. using different methods of investigation several types of muscle destruction were shown. i. destruction of myofibrillar apparatus (lysis of protofibrils), with sarcolemma remain ... | 2000 | 10709249 |
| individual specialization and trophic adaptability of northern pike (esox lucius): an isotope and dietary analysis. | northern pike (esox lucius) are often considered to be specialist piscivores, but under some circumstances will continue to eat invertebrates as adults. to examine effects of fish assemblage composition on the trophic ecology of pike, we combined stable isotope analysis (sia) of carbon and nitrogen and stomach content analysis (sca) on pike from five lakes in northern alberta, three of which contain only pike ("pike-only") and two that also contain yellow perch (perca flavescens) or white sucker ... | 1999 | 28308015 |
| piscivore efficiency and refuging prey: the importance of predator search mode. | in predator-prey interactions, the efficiency of the predator is dependent on characteristics of both the predator and the prey, as well as the structure of the environment. in a field enclosure experiment, we tested the effects of a prey refuge on predator search mode, predator efficiency and prey behaviour. replicated enclosures containing young of the year (0+) and 1-year-old (1+) perch were stocked with 3 differentially sized individuals of either of 2 piscivorous species, perch (perca fluvi ... | 1994 | 28313911 |
| factors affecting trace-metal bioaccumulation in finnish headwater lakes. | fourteen unpolluted finnish headwater lakes with ph values varying from 4.8 to 7.0 were studied for trace-metal concentrations in water, sediment, aquatic plants (nuphar luteum l., sparganium sp.), aquatic insect larvae (limnophilus sp., phryganea sp.) and fish (esox lucius l., perca fluviatilis l., coregonus sp., salvelinus fontinalis l., salmo trutta l.). trace-metal deposition was estimated by analysing the snowpack. non-parametric correlation analysis was carried out between trace metal conc ... | 1992 | 15091932 |
| metabolic rate and cost of growth in juvenile pike (esox lucius l.) and perch (perca fluviatilis l.): the use of energy budgets as indicators of environmental change. | energy budgets of juvenile pike and perch (weighing approximately 3 g) were determined in experiments lasting up to 4 days, by simultaneously measuring oxygen consumption, food consumption, and growth of individual fish. although the basic pattern of energy allocation was identical in the two species, perch subjected to constant light (pel) showed faster growth, higher assimilation and conversion efficiency, and higher oxygen consumption than perch subjected to a short daylength regime (ped). th ... | 1991 | 28313691 |
| the receptive field structure of visual cells from the optic tectum of the freshwater perch (perca fluviatilis). | recordings from the intrinsic tectal cells of the perch have allowed a classification of visual units on the basis of receptive field type. comparisons with retinal and tectal cells in carp, goldfish, pike, trout and in the anura were made. most striking are cells with vertical bar-shaped features forming part of the r.f. the relation between the receptive fields of units lying adjacent within the tectum, suggests that parts of the same pattern are derived from cells within the same vertical col ... | 1978 | 626899 |
| young northern pike, yellow perch and crayfish as bioindicators in a mercury contaminated watercourse. | young-of-the-year and yearling northern pike (esox lucius), yearling yellow perch (perca flavescens) and adult crayfish (orconectes virilis) were collected in the mercury-contaminated wabigoon/english/winnipeg river system, ontario, and analyzed for total mercury. analysis of mercury concentrations in these organisms produced consistent geographical trends; i.e. mercury concentrations in biota downstream of dryden > english river system > winnipeg river system > control sites. in the wabigoon ri ... | 1991 | 24241775 |
| the selenium method for treatment of lakes for elevated levels of mercury in fish. | selenium in the form of sodium selenite (na2seo3) incorporated in a rubber matrix was introduced into a swedish lake which is black-listed for fishing because of high mercury levels in fish tissues. the lake is not acidified. the level of selenium in the lake was raised from 0.4 to approximately 3-5 micrograms se l-1, and sustained at this level for a period of greater than 3 years. the mercury content of pike (esox lucius) was found to have fallen markedly after the lake had been treated for on ... | 1989 | 2558416 |
| in vitro biosynthesis of 11beta-hydroxy- and 11-oxotestosterone by testes of the pike (esox lucius) and the perch (perca fluviatilis). | | 1978 | 750289 |
| effect of temperature on mortality and rate of development of the eggs of the pike (esox lucius l.) and the perch (perca fluviatilis l.). | | 1965 | 5890658 |
| mercury in freshwater fish of northeast north america--a geographic perspective based on fish tissue monitoring databases. | as part of an initiative to assemble and synthesize mercury (hg) data from environmental matrices across northeastern north america, we analyzed a large dataset comprised of 15,305 records of fish tissue hg data from 24 studies from new york state to newfoundland. these data were summarized to provide mean hg concentrations for 40 fish species and associated families. detailed analyses were carried out using data for 13 species. hg in fishes varied by geographic area, waterbody type, and waterbo ... | 2005 | 15931965 |
| induction of gynogenesis in muskellunge with irradiated sperm of yellow perch proves diploid muskellunge male homogamety. | diploid gynogenesis was induced in muskellunge esox masquinongy using uv-irradiated muskellunge sperm as the first step in producing monosex females. in this approach, we have to rely on negative controls as an indirect reference for sperm genetic material destruction. in the first experiment, equal proportions of gynogenetic females and males were produced. negative controls, uv-irradiated sperm without heat shock, yielded some normal hatching larvae, described as spontaneous diploids. in the s ... | 2000 | 10861556 |
| hypoxia, blackwater and fish kills: experimental lethal oxygen thresholds in juvenile predatory lowland river fishes. | hypoxia represents a growing threat to biodiversity in freshwater ecosystems. here, aquatic surface respiration (asr) and oxygen thresholds required for survival in freshwater and simulated blackwater are evaluated for four lowland river fishes native to the murray-darling basin (mdb), australia. juvenile stages of predatory species including golden perch macquaria ambigua, silver perch bidyanus bidyanus, murray cod maccullochella peelii, and eel-tailed catfish tandanus tandanus were exposed to ... | 2014 | 24728094 |
| effect of flower shape and size on foraging performance and trade-offs in a tropical hummingbird. | matches between the bills of hummingbirds and the flowers they visit have been interpreted as examples of coadaptation and feeding specialization. observations of birds feeding at flowers longer or shorter than their bills combined with a lack of experimental evidence for foraging trade-offs, however, fail to support these interpretations. we addressed these inconsistencies by considering a seldom-studied dimension of hummingbird-flower relationships, the shape of bills and flowers, through expe ... | 2009 | 19537537 |
| proportion of prey consumed can be determined from faecal dna using real-time pcr. | reconstructing the diets of pinnipeds by visually identifying prey remains recovered in faecal samples is challenging because of differences in digestion and passage rates of hard parts. analysing the soft-matrix of faecal material using dna-based techniques is an alternative means to identify prey species consumed, but published techniques are largely nonquantitative, which limits their usefulness for some applications. we further developed and validated a real-time pcr technique using species- ... | 2011 | 21481211 |
| frugivory and seed dispersal by birds in cereus jamacaru dc. ssp. jamacaru (cactaceae) in the caatinga of northeastern brazil. | studies of the dispersal modes of plants aid our understanding of the dynamics of resource and its availability for dispersal agents. the present work sought to characterize the fruiting patterns of the native caatinga (dryland) cactus cereus jamacaru, identify its principal dispersers, and evaluate the effects of seed passage through digestive tract of dispersers on its germination. cereus jamacaru present an annual fruiting pattern and fruiting peaks occurred during june/2009 and february/2010 ... | 2014 | 25055084 |
| courtship behavior of captive american kestrels (falco sparverius) exposed to polychlorinated biphenyls. | polychlorinated biphenyls (pcbs) adversely affect reproduction in birds. captive adult male and female american kestrels (falco sparverius) were studied to investigate the potential behavioral and hormonal alterations during the courtship period resulting from clinical exposure to pcbs. american kestrels ingested 7 mg/kg/body weight/bird/day of a 1:1:1 mixture of aroclors 1248, 1254, and 1260 through their diet of day-old cockerels. the dietary dosage of aroclors resulted in environmentally rele ... | 2001 | 11462146 |
| behavior of captive american kestrels hatched from o,p'-dicofol exposed females. | a two-generation laboratory study was conducted on captive american kestrels (falco sparverius) to investigate the possible behavioral alterations from the compound o,p'-dicofol. paired females were exposed to three levels of dicofol by oral gavage. adults of the second generation, exposed only via the maternal dose of o,p'-dicofol at 5- and 20-mg/kg, displayed negatively correlated changes in reproductive behaviors. second generation females showed a significant difference (p < 0.05) from contr ... | 1997 | 9175508 |
| predator presence may benefit: kestrels protect curlew nests against nest predators. | we studied whether the presence of breeding kestrels (falco tinnunculus) affected nest predation and breeding habitat selection of curlews (numenius arquata) on an open flat farmland area in western finland. we searched for nests of curlews from an area of 6 km(2) during 1985-1993. for each nest found, we recorded the fate of the nest, and the distance to the nearest kestrel nest and to the nearest perch. we measured the impact of breeding kestrels on nest predation by constructing artificial cu ... | 1995 | 28306982 |
| testing the potential for predictive modeling and mapping and extending its use as a tool for evaluating management scenarios and economic valuation in the baltic sea (prehab). | we evaluated performance of species distribution models for predictive mapping, and how models can be used to integrate human pressures into ecological and economic assessments. a selection of 77 biological variables (species, groups of species, and measures of biodiversity) across the baltic sea were modeled. differences among methods, areas, predictor, and response variables were evaluated. several methods successfully predicted abundance and occurrence of vegetation, invertebrates, fish, and ... | 2014 | 24414807 |
| vitellogenin of the chilean flounder paralichthys adspersus as a biomarker of endocrine disruption along the marine coast of the south pacific. part i: induction, purification, and identification. | we sought to provide a useful indicator of the presence of endocrine-disrupting contaminants along the marine coast of the south pacific using chilean flounder (paralichthys adspersus). in light of the lack of information on vitellogenin for this species, we induced, purified, and identified the plasma vitellogenin of chilean flounder inhabiting the chilean coast. vitellogenin (vg) from chilean flounder was purified by size exclusion and ion-exchange chromatography using plasma from juvenile mal ... | 2010 | 19685217 |
| from genes to populations: how fisheries-induced evolution alters stock productivity. | by removing individuals with certain heritable characteristics such as large body size, harvesting may induce rapid evolutionary change in fish life history. there is controversy, however, as to the prevalence of fisheries-induced evolution (fie) and to what extent it should be considered as part of sustainable resource management. recent research has shown that fie can be difficult to detect and its economic effects might not always be significant. here, we show how population growth rate (r), ... | 2015 | 26591452 |
| identification of new potential allergens from nile perch (lates niloticus) and cod (gadus morhua). | globalization of the food industry has led to widespread exposure to new nondomestic fish species; therefore, identification of potential allergens is necessary in order to diagnose allergic reactions. | 2013 | 23967754 |
| embryonic stem cells isolated from atlantic cod (gadus morhua) and the developmental expression of a stage-specific transcription factor ac-pou2. | the establishment of embryonic stem cell cultures and the identification of molecular markers for undifferentiated embryonic stem cells (esc) as well as differentiated cells types will open new opportunities in the study of developmental biology and for developing embryonic in vitro models of the ecologically and economically important fish specie atlantic cod (gadus morhua). we report here that cod blastula cells express a class v pou gene known to be highly expressed in embryonic cell populati ... | 2010 | 20130987 |
| immunochemical cross-reactivity ofβ-naphthoflavone-inducible cytochrome p450 (p450ia) in liver microsomes from different fish species and rat. | antibodies prepared against the major β-naphthoflavone (bnf)-inducible cytochrome p450 (p450) forms from three species of fish (rainbow trout, atlantic cod, and scup) well separated in teleost phylogeny, were used to investigate the immunochemical relatedness of liver microsomal p450 in different species of bnf-treated fish and rat. rabbit polyclonal igg against all three p450s and mouse monoclonal antibodies prepared against scup p450e were employed in this study. liver microsomes were prepared ... | 1991 | 24214604 |
| mercury in flounder, platichtys flesus, cod, gadus morhua, and perch, perca fluviatilis, in relation to their length and environment. | | 1987 | 3801704 |
| exposure to increased environmental complexity during rearing reduces fearfulness and increases use of three-dimensional space in laying hens (gallus gallus domesticus). | the complexity of the rearing environment is important for behavioral development and fearfulness. the aim of this study was to test the hypothesis that laying hens reared in a complex aviary system with exposure to mild intermittent stressors would be less fearful, less sensitive to stress, and would use elevated areas of the pen more often as adults than hens reared in a barren cage environment. laying hens (n = 160) were housed in the same rearing house; half of the birds (n = 80) in an aviar ... | 2016 | 26973843 |
| application of the luminometric methylation assay to ecological species: tissue quality requirements and a survey of dna methylation levels in animals. | the luminometric methylation assay (luma) measures global dna methylation. luma depends on digestion of dna with methyl-sensitive and methyl-insensitive restriction enzymes, followed by pyrosequencing. until recently, luma has been principally used for biomedical research. here, we use chickens as a model to investigate sample quality issues relating to luma and then apply the method to ecological species. first, we assessed the effect of tissue storage conditions on dna methylation values. this ... | 2014 | 24576185 |
| effects of methylmercury on epigenetic markers in three model species: mink, chicken and yellow perch. | we previously reported that methylmercury (mehg) exposure is associated with dna hypomethylation in the brain stem of male polar bears. here, we conveniently use archived tissues obtained from controlled laboratory exposure studies to look for evidence that mehg can disrupt dna methylation across taxa. brain (cerebrum) tissues from mehg-exposed mink (neovison vison), chicken (gallus gallus) and yellow perch (perca flavescens) were analyzed for total hg levels and global dna methylation. tissues ... | 2013 | 23481557 |
| the behavioural priorities of laying hens: the effect of cost/no cost multi-choice tests on time budgets. | a multi-choice situation offering a number of presumably significant environmental features may reveal an animal's immediate preferences concerning its environment and how it wants to distribute its time budget. in this study the time budgets of hens (gallus gallus domesticus) were examined in a free access situation (no cost condition) and in a situation in which there was a cost for access (cost condition). the options consisted of six pens that could be entered from a middle pen which had no ... | 1996 | 24897445 |
| demand for nest boxes in laying hens. | domestic hens (gallus gallus domesticus) from commercial laying strains have been selected for high egg yield and may lay over 300 eggs in their working lives. in conventional wire cages, there is little opportunity to perform either nest seeking or nest building activities, which may lead to frustration each time an egg is laid. to measure the demand for a well-defined nest-site, which may act as a consummatory stimulus for nest seeking behaviour and an appetitive stimulus for nest building beh ... | 1996 | 24896684 |
| careful cachers and prying pilferers: eurasian jays (garrulus glandarius) limit auditory information available to competitors. | food-storing corvids use many cache-protection and pilfering strategies. we tested whether eurasian jays (garrulus glandarius) reduce the transfer of auditory information to a competitor when caching and pilfering. we gave jays a noisy and a quiet substrate to cache in. compared with when alone, birds cached less in the noisy substrate when with a conspecific that could hear but could not see them caching. by contrast, jays did not change the amount cached in the noisy substrate when they were w ... | 2013 | 23222444 |
| trophic transfer of naturally produced brominated aromatic compounds in a baltic sea food chain. | brominated aromatic compounds (bacs) are widely distributed in the marine environment. some of these compounds are highly toxic, such as certain hydroxylated polybrominated diphenyl ethers (oh-pbdes). in addition to anthropogenic emissions through use of bacs as e.g. flame retardants, bacs are natural products formed by marine organisms such as algae, sponges, and cyanobacteria. little is known of the transfer of bacs from natural producers and further up in the trophic food chain. in this study ... | 2016 | 26517387 |
| declining coastal piscivore populations in the baltic sea: where and when do sticklebacks matter? | intraguild predation interactions make fish communities prone to exhibit alternative stable states with either piscivore or prey fish dominance. in the baltic sea, local declines of coastal piscivores like perch (perca fluviatilis) have been observed to coincide with high densities of sticklebacks (gasterosteus aculeatus). mechanisms behind this shift between piscivore and stickleback dominance were studied both experimentally and in field. results showed that predation by sticklebacks has a str ... | 2015 | 26022328 |
| coexistence of fish species in a large lowland river: food niche partitioning between small-sized percids, cyprinids and sticklebacks in submersed macrophytes. | in the spring and summer of each year, large patches of submersed aquatic macrophytes overgrow the bottom of the alluvial warta river downstream of a large dam reservoir owing to water management practices. environmental variables, macroinvertebrates (zoobenthos and epiphytic fauna, zooplankton) and fish abundance and biomass were assessed at this biologically productive habitat to learn intraseasonal dynamics of food types, and their occurrence in the gut contents of small-sized roach, dace, pe ... | 2014 | 25365420 |
| individuals' diet diversity influences gut microbial diversity in two freshwater fish (threespine stickleback and eurasian perch). | vertebrates' diets profoundly influence the composition of symbiotic gut microbial communities. studies documenting diet-microbiota associations typically focus on univariate or categorical diet variables. however, in nature individuals often consume diverse combinations of foods. if diet components act independently, each providing distinct microbial colonists or nutrients, we expect a positive relationship between diet diversity and microbial diversity. we tested this prediction within each of ... | 2014 | 24847735 |
| major correlates of mercury in small fish and common loons (gavia immer) across four large study areas in canada. | we investigated mercury (hg) concentrations in small fish (mainly yellow perch, perca flavescens; ∼60% of fish collected) and in blood of common loons (gavia immer) that prey upon them during the breeding season on lakes in 4 large, widely separated study areas in canada (>13 lakes per study area; total number of lakes = 93). although surface sediments from lakes near a base metal smelter in flin flon, manitoba had the highest hg concentrations, perch and other small fish and blood of common loo ... | 2016 | 26803793 |
| spatial gradients of methylmercury for breeding common loons in the laurentian great lakes region. | much of the laurentian great lakes region is a mercury-sensitive landscape, in which atmospheric deposition and waterborne sources of mercury (hg) have led to high concentrations of bioavailable methylmercury (mehg) in predatory fish and piscivorous wildlife. efforts since the early 1990s have established the common loon (gavia immer) as the primary avian indicator for evaluating the exposure and effects of mehg in north america. a regional hg dataset was compiled from multiple loon tissue types ... | 2011 | 21858513 |
| increasing mercury in yellow perch at a hotspot in atlantic canada, kejimkujik national park. | in the mid-1990s, yellow perch (perca flavescens) and common loons (gavia immer) from kejimkujik national park and national historic site (knpnhs), nova scotia, canada, had among the highest mercury (hg) concentrations across north america. in 2006 and 2007, we re-examined 16 lakes to determine whether there have been changes in hg in the loon's preferred prey, yellow perch. total hg concentrations were measured in up to nine perch in each of three size classes (5-10 cm, 10-15 cm, and 15-20 cm) ... | 2010 | 21062071 |
| transition from wing to leg forces during landing in birds. | transitions to and from the air are critical for aerial locomotion and likely shaped the evolution of flying animals. research on take-off demonstrates that legs generate greater body accelerations compared with wings, and thereby contribute more to initial flight velocity. here, we explored coordination between wings and legs in two species with different wingbeat styles, and quantified force production of these modules during the final phase of landing. we used the same birds that we had previ ... | 2014 | 24855670 |
| transition from leg to wing forces during take-off in birds. | take-off mechanics are fundamental to the ecology and evolution of flying animals. recent research has revealed that initial take-off velocity in birds is driven mostly by hindlimb forces. however, the contribution of the wings during the transition to air is unknown. to investigate this transition, we integrated measurements of both leg and wing forces during take-off and the first three wingbeats in zebra finch (taeniopygia guttata, body mass 15 g, n=7) and diamond dove (geopelia cuneata, body ... | 2012 | 22972887 |
| analysis of effectiveness of three forest interventionist techniques and proposal of a new and integrated model of forest restoration. | we assessed the efficacy of three different forest intervention techniques, in terms of phytosociological and edaphic responses, that were implemented in 2007. in a farm where trees are planted and managed for cellulose production as well as set aside for environmental conservation, four stands were analysed: three of them were considered degraded and were managed using different intervention techniques (transposition, perch, and abandonment), and a fourth stand comprising pristine vegetation wa ... | 2015 | 25970012 |
| histopathology and the inflammatory response of european perch, perca fluviatilis muscle infected with eustrongylides sp. (nematoda). | the european perch, perca fluviatilis l. is a common paratenic host of dioctophymatid nematodes belonging to the genus eustrongylides. in this host, once infected oligochaetes, which serve as the first intermediate host, are ingested, eustrongylides migrates through the intestine and is frequently encountered within the musculature, free within the body cavity, or encapsulated on the viscera. the current study details the first italian record of eustrongylides sp. with larvae reported in the mus ... | 2015 | 25889096 |
| exposure to bloom-like concentrations of two marine synechococcus cyanobacteria (strains cc9311 and cc9902) differentially alters fish behaviour. | coastal california experiences large-scale blooms of synechococcus cyanobacteria, which are predicted to become more prevalent by the end of the 21st century as a result of global climate change. this study investigated whether exposure to bloom-like concentrations of two synechococcus strains, cc9311 and cc9902, alters fish behaviour. black perch (embiotoca jacksoni) were exposed to synechococcus strain cc9311 or cc9902 (1.5 × 10(6) cells ml(-1)) or to control seawater in experimental aquaria f ... | 2014 | 27293641 |
| basic ecology of the oaxacan spiny-tailed iguana ctenosaura oaxacana (squamata: iguanidae), in oaxaca, mexico. | the oaxacan spiny-tailed iguana ctenosaura oaxacana is a restricted species to the isthmus of tehuantepec in southern oaxaca, mexico. this reptile is one of the less known iguanid species. we census-tracked a population in the south ofniltepec, oaxaca, mexico from may 2010 to april 2011. throughout one year, a total of 10 line transects were situated and recorded in the study area to determine relative abundance and density, and habitat type use (dry forest, nanchal, grassland, riparian vegetati ... | 2012 | 23342515 |