| parasites of native and nonnative fishes of the little colorado river, grand canyon, arizona. | a 2-yr, seasonal, parasitological study of 1,435 fish, belonging to 4 species of native fishes and 7 species of nonnative fishes from the lower little colorado river (lcr) and tributary creeks, grand canyon, arizona, yielded 17 species of parasites. these comprised 1 myxozoan (henneguya exilis), 2 copepods (ergasilus arthrosis and lernaea cyprinacea), 1 acarine (oribatida gen. sp.), 1 piscicolid leech (myzobdella lugubris), 4 monogeneans (gyrodactylus hoffmani, gyrodactylus sp., dactylogyrus ext ... | 2004 | 15562604 |
| infection by a black spot-causing species of uvulifer and associated opercular alterations in fishes from a high-desert stream in wyoming. | black spot is a common disease syndrome of freshwater fishes. this study provides information on the rank of density of the black spot agent and opercular bone alterations associated with at least one digenean, uvulifer sp., infecting native and non-native catostomids and cyprinids of the upper colorado river basin. we evaluated the density rank of pigmented metacercariae and associated alterations in the operculum of the bluehead sucker catostomus discobolus, flannelmouth sucker c. latipinnis, ... | 2007 | 18286809 |
| parasites of fishes in the colorado river and selected tributaries in grand canyon, arizona. | abstract as part of the endangered humpback chub (hbc) gila cypha adaptive management program, a parasite survey was conducted from 28 june - 17 july 2006 in 8 tributaries and 7 adjacent sections of the main stem colorado river (cor). in total 717 fish were caught, including 24 hbc, field necropsies yielded 19 parasite species, 5 of which (achtheres sp., kathlaniidae gen. sp., caryophyllaidae gen. sp., myxidium sp., and octomacrum sp.) are new records for the grand canyon. spearman's correlation ... | 2011 | 21793700 |
| acute toxicity of zinc to several aquatic species native to the rocky mountains. | national water-quality criteria for the protection of aquatic life are based on toxicity tests, often using organisms that are easy to culture in the laboratory. species native to the rocky mountains are poorly represented in data sets used to derive national water-quality criteria. to provide additional data on the toxicity of zinc, several laboratory acute-toxicity tests were conducted with a diverse assortment of fish, benthic invertebrates, and an amphibian native to the rocky mountains. tes ... | 2012 | 21811884 |
| prey capture behavior of native vs. nonnative fishes: a case study from the colorado river drainage basin (usa). | the colorado river drainage basin is home to a diverse but imperiled fish fauna; one putative challenge facing natives is competition with nonnatives. we examined fishes from colorado river tributaries to address the following questions: do natives and nonnatives from the same trophic guild consume the same prey items? will a given species alter its behavior when presented with different prey types? do different species procure the same prey types via similar feeding behaviors? roundtail chub (g ... | 2012 | 22514041 |
| an occupancy-based quantification of the highly imperiled status of desert fishes of the southwestern united states. | desert fishes are some of the most imperiled vertebrates worldwide due to their low economic worth and because they compete with humans for water. an ecological complex of fishes, 2 suckers (catostomus latipinnis, catostomus discobolus) and a chub (gila robusta) (collectively managed as the so-called three species) are endemic to the u.s. colorado river basin, are affected by multiple stressors, and have allegedly declined dramatically. we built a series of occupancy models to determine relation ... | 2015 | 25900520 |
| of travertine and time: otolith chemistry and microstructure detect provenance and demography of endangered humpback chub in grand canyon, usa. | we developed a geochemical atlas of the colorado river in grand canyon and in its tributary, the little colorado river, and used it to identify provenance and habitat use by federally endangered humpback chub, gila cypha. carbon stable isotope ratios (δ(13)c) discriminate best between the two rivers, but fine scale analysis in otoliths requires rare, expensive instrumentation. we therefore correlated other tracers (srsr, ba, and se in ratio to ca) to δ(13)c that are easier to quantify in otolith ... | 2013 | 24358346 |
| establishing a captive broodstock for the endangered bonytail chub (gila elegans). | it is crucial for endangered species to retain as much genetic variation as possible to enhance recovery. bonytail chub (gila elegans) is one the most imperiled freshwater fish species, persisting as a declining population of large and old individuals primarily in lake mohave on the lower colorado river. establishment of a new captive broodstock from the 1981 f1 progeny of at most 10 wild fish plus any newly captured wild fish is evaluated and reviewed. the effective number of founders contribut ... | 2008 | 10739122 |
| presence and effects of pharmaceutical and personal care products on the baca national wildlife refuge, colorado. | pharmaceuticals and personal care products (ppcps) have raised concerns due to their potential effects to aquatic organisms. these chemicals appear in mixtures at very low concentrations thus making their detection and quantification difficult. polar organic chemical integrative samplers (pocis) concentrate trace levels of chemicals over time increasing method sensitivity and thus represent a cost-effective screening tool for biomonitoring studies. the baca national wildlife refuge (bnwr), color ... | 2015 | 25465958 |