| species of apatemon szidat, 1928 and australapatemon sudarikov, 1959 (trematoda: strigeidae) from new zealand: linking and characterising life cycle stages with morphology and molecules. | species of apatemon szidat, 1928 and australapatemon sudarikov, 1959 are reported from new zealand for the first time, and their life cycles are resolved using molecular sequence data (28s and its rdna regions and mitochondrial coi). the metacercaria of apatemon sp. 'jamiesoni' ex gobiomorphus cotidianus and its cercaria ex potamopyrgus antipodarum are described in detail. its adult, found in anas platyrhynchos and phalacrocorax punctatus, is identified by molecular sequence data. apatemon sp. ' ... | 2016 | 26385467 |
| monitoring the effects of pulp and paper effluent is restricted in genetically distinct populations of common bully (gobiomorphus cotidianus). | the common bully (gobiomorphus cotidianus), a small-bodied new zealand native fish species, was used to monitor population impacts of multiple effluents in the tarawera river, new zealand. in an initial survey, the absence of reproductive development at the expected spawning time for common bullywas observed in a population downstream of effluent discharges. subsequently, we examined the hypotheses that the observed changes were due to effluent exposure, migratory patterns, or genetic difference ... | 2007 | 17438822 |
| distinct migratory and non-migratory ecotypes of an endemic new zealand eleotrid (gobiomorphus cotidianus) - implications for incipient speciation in island freshwater fish species. | many postglacial lakes contain fish species with distinct ecomorphs. similar evolutionary scenarios might be acting on evolutionarily young fish communities in lakes of remote islands. one process that drives diversification in island freshwater fish species is the colonization of depauperate freshwater environments by diadromous (migratory) taxa, which secondarily lose their migratory behaviour. the loss of migration limits dispersal and gene flow between distant populations, and, therefore, is ... | 2008 | 18275608 |
| bullying in adolescence: psychiatric problems in victims and bullies as measured by the youth self report (ysr) and the depression self-rating scale (dsrs). | adolescents in junior high school (n = 237), completed a questionnaire on bullying as it relates to victim and to perpetrator status, suicidality and biographical data. psychological symptoms were assessed by the youth self report (ysr) and the depression self-rating scale (dsrs) supplemented by school health officers blind assessments. bullying was common: bully only (18%), victim only (10%) and victim and bully (9%). bullies had mainly externalizing symptoms (delinquency and aggression) and th ... | 2005 | 16757465 |
| habitat-specific variation and performance trade-offs in shell armature of new zealand mudsnails. | studies documenting phenotypic variation among populations show that ecological performance in one activity is sometimes traded off against another. identifying environment-specific costs and benefits associated with performance trade-offs is fundamental to knowing how conflicting selection pressures shape phenotype-environment matching in populations. we studied phenotypic variation in shell armature (spininess) of the new zealand mudsnail, potamopyrgus antipodarum (gray), and explored how this ... | 2006 | 16676547 |
| First report of a gryporhynchid tapeworm (Cestoda: Cyclophyllidea) from New Zealand and from an eleotrid fish, described from metacestodes and in vitro-grown worms. | Metacestodes are often found in the body cavity of the common bully (Gobiomorphus cotidianus McDowall), from freshwater habitats in Otago, New Zealand. Identification of metacestodes relies only on the number, size and shape of the rostellar hooks. To attempt species determination, we cultivated metacestodes in vitro for up to 23 days, during which they matured to at least the male stage of development, although female organs were not discernable. Identified as members of the genus Paradilepis H ... | 2011 | 22152219 |
| carotenoid depletion and ovarian dysfunction in common bully exposed to a new zealand pulp mill effluent. | in a previous cumulative impacts assessments of fish populations along the waikato river, new zealand, reduced ovary pigmentation was observed in the common bully (gobiomorphus cotidianus) with an associated reduction in recruitment in the pulp mill-impacted kopakorahi arm of lake maraetai compared to an upstream reference site. carotenoid pigments are typically responsible for the yellow to red colouration of fish eggs and a number of functions for these pigments such as pro-vitamins and antiox ... | 2008 | 18394728 |
| body condition peaks at intermediate parasite loads in the common bully gobiomorphus cotidianus. | most ecologists and conservationists perceive parasitic infections as deleterious for the hosts. their effects, however, depend on many factors including host body condition, parasite load and the life cycle of the parasite. more research into how multiple parasite taxa affect host body condition is required and will help us to better understand host-parasite coevolution. we used body condition indices, based on mass-length relationships, to test the effects that abundances and biomasses of six ... | 2016 | 28030606 |
| morphological description and molecular analyses of tylodelphys sp. (trematoda: diplostomidae) newly recorded from the freshwater fish gobiomorphus cotidianus (common bully) in new zealand. | among eyeflukes, tylodelphys diesing, 1850 includes diverse species able to infect the eyes, but also the brain, pericardial sac and body cavity of their second intermediate host. while the genus shows a cosmopolitan distribution with 29 nominal species in africa, asia, europe and america, a likely lower research effort has produced two records only for all of australasia. this study provides the first description of a species of tylodelphys and the first record for a member of the diplostomidae ... | 2017 | 27225234 |
| effect of ramp length and slope on the efficacy of a baffled fish pass. | this study evaluated the effect of ramp length and slope on fish passage over baffled ramps with 15° and 30° gradients. three fish species indigenous to new zealand were tested: the redfin bully gobiomorphus huttoni, the common bully gobiomorphus cotidianus and the inanga galaxias maculatus with ramp lengths of 3, 4·5 and 6 m. as slope and ramp length increased, passage success rate decreased for g. maculatus and g. cotidianus. at a slope of 15°, both g. maculatus and g. cotidianus could pass al ... | 2014 | 24417428 |
| measuring fish body condition with or without parasites: does it matter? | a fish body condition index was calculated twice for each individual fish, including or excluding parasite mass from fish body mass, and index values were compared to test the effects of parasite mass on measurement of body condition. potential correlations between parasite load and the two alternative fish condition index values were tested to assess how parasite mass may influence the perception of the actual effects of parasitism on fish body condition. helminth parasite mass was estimated in ... | 2015 | 26283054 |
| possible mechanism of host manipulation resulting from a diel behaviour pattern of eye-dwelling parasites? | parasitic infection often results in alterations to the host's phenotype, and may modify selection pressures for host populations. elucidating the mechanisms underlying these changes is essential to understand the evolution of host-parasite interactions. a variety of mechanisms may result in changes in the host's behavioural phenotype, ranging from simple by-products of infection to chemicals directly released by the parasite to alter behaviour. another possibility may involve parasites freely m ... | 2016 | 27216502 |
| the missing host hypothesis: do chemical cues from predators induce life cycle truncation of trematodes within their fish host? | using controlled experiments, the ability of the trematode parasite stegodexamene anguillae, encysted within its intermediate fish host, the common bully gobiomorphus cotidianus, was tested to indirectly detect the presence of its definitive host by exposing infected g. cotidianus to chemical cues from the definitive host, the short-finned eel anguilla australis. the trematode can abbreviate its normal life cycle and achieve precocious maturity in g. cotidianus, or adopt the usual strategy consi ... | 2012 | 22471801 |
| habitat-related specialization of lateral-line system morphology in a habitat-generalist and a habitat-specialist new zealand eleotrid. | an investigation of intraspecific habitat-related patterns of variation in oculoscapular lateral-line superficial neuromasts (sn) identified a decrease in the ratio of total sns to pores, and a trend towards decreased asymmetry in sns in the habitat-generalist common bully gobiomorphus cotidianus from fluvial habitats compared to lacustrine habitats, suggesting habitat-related phenotypic variability. a greater ratio of pores to sns, as well as less variation in the total number and asymmetry of ... | 2016 | 26892757 |