Filters: Extensions: Citation (X) > partyWithName: Keith B Gido (X)
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Description: The upper Gila River in New Mexico is one of the few unobstructed rivers in the Colorado River Basin with largely intact native fish populations, including four federally listed and one state listed species.Freshwater systems throughout the West continue to be threatened by human encroachment and water development. Methodologies or decision support tools to evaluate resource management practices that foster an understanding of how fish species adapt to the effects of climate change are critical to future resource management planning.
Categories: Data,
Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2011,
AZ-01,
AZ-02,
Academics & scientific researchers,
Applications and Tools,
Spatial patterns of resource use by small-bodied fishes in the San Juan River were examined using stable isotopes. Using δ15N of fishes as an index of trophic position, our data suggest both native and non-native fishes primarily consumed macro-invertebrates. The δ13C of these fishes further suggested a detritus-based food web, from which most species fed on chironomids in low-velocity habitats. A two-way ANOVA revealed a significant interaction between trophic level of fish species and longitudinal position in the river. This interaction was primarily attributed to a decline in trophic level of non-native red shiner Cyprinella lutrensis, relative to other species, in upstream reaches of the river. In addition,...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Environmental Biology of Fishes,
Springer Netherlands,
food web,
introduced species,
longitudinal gradients,
Escalating demands for water have led to substantial modifications of river systems in arid regions, which coupled with the widespread invasion of nonnative organisms, have increased the vulnerability of native aquatic species to extirpation. Whereas a number of studies have evaluated the role of modified flow regimes and nonnative species on native aquatic assemblages, few have been conducted where the compounding effects of modified flow regimes and established nonnatives do not confound interpretations, particularly at spatial and temporal scales that are relevant to conservation of species at a range-wide level. By evaluating a 19-year data set across six sites in the relatively unaltered upper Gila River basin,...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Ecological Applications,
Gila River,
New Mexico,
climate cycles,
disturbance regime,
Habitat use and associations of native and nonnative fish species in secondary channels of the San Juan River, New Mexico and Utah were investigated. Most species and age classes within species (larvae, juveniles, subadults, and adults) used low velocity habitats with silt substrata. Discriminant function analysis revealed broad overlap in habitat use among species, with a trend of older age classes occurring in deeper habitats with faster current velocities. Overall, discriminant function analysis was able to correctly classify species and age classes, based on habitat use, 23.4% of the time. Native juvenile fishes exhibited the greatest interspecific association with nonnative fishes, whereas adult and subadult...
Ecological thresholds that lead to alternative community states can be exceeded through gradual perturbation or as a result of sudden disturbance. Many Great Plains streams have experienced dramatic changes in their hydrologic regime resulting from water and landuse changes that began as early as 1880. These changes, combined with the presence of many invasive species, have substantially altered the fish communities in this area. We quantified temporal changes in fish communities in 3 large river basins in relation to putative anthropogenic stressors, including increased sediment supply derived from row-crop agriculture (beginning in 1880), habitat fragmentation caused by reservoir construction (beginning in the...
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