Theodore A Kennedy

Invertebrate data (2012-2021) from the Colorado River in Grand Canyon and flow data (1921-2021) from the Lees Ferry gage (09380000) on the Colorado River near Page, AZ

These data were compiled for an outreach article published in the Boatman's Quarterly Review, which is a magazine published by Grand Canyon River Guides Association. The objectives of our study was to describe the outcomes of the 2018-2020 Bug Flows experiment to a general audience. These data represent 10 years (2012-2021) of invertebrate data and 100 years (1921-2021) of flow data. These data were collected from the Colorado River in Glen Canyon National Recreation Area and Grand Canyon National Park. These data were collected by recreational river runners through a community science effort where we provided river runners with light trapping equipment to sample emergent aquatic insects each night of their expeditions....

Categories: Data; Tags: Aquatic Biology, Arizona, Colorado River, Ecology, Geography, All tags... Glen Canyon, Glen Canyon National Recreation Area, Grand Canyon, Grand Canyon National Park, Havasupai Reservation, Hualapai Indian Reservation, Hydrology, Information Sciences, Lees Ferry, Navajo Nation Reservation, USGS Science Data Catalog (SDC), USGS gage 09380000, adult insects, aquatic biology, aquatic ecosystems, aquatic insects, biota, bug Flows experiment, catch rate, citizen science programs, community science, data release, emergence rates, field experiments, field sampling, inlandWaters, insects, invertebrate counts, invertebrate data, invertebrates, life sciences, light traps, river runner, sampling duration, stage variation, stream flow data, stream-gage measurement, Fewer tags

Rainbow trout diet and invertebrate drift data from 2012-2015 for the Colorado River, Grand Canyon, Arizona

These data were compiled to explore the foraging ecology of Rainbow Trout (Oncorhynchus mykiss) in the Colorado River, Grand Canyon, Arizona. These data represent samples characterizing the availability of drifting invertebrate prey (hereafter, drift) and use of these invertebrate prey by rainbow trout determined by gut samples (hereafter, diets). Drift and diet sampling occurred in five distinct reaches downstream of Glen Canyon Dam (river kilometer (rkm) from the dam): (I) rkm 16.3-21.7; (II) rkm 52.8-58.3; (III) rkm 86.6-91.9; (IV) rkm 122.0-123.6; and (V) rkm 127.1-129.6. Samples were taken on 12 trips in April, July, September and January from April 2012 through January 2015. The aquatic prey base consists...

Categories: Data; Tags: Aquatic Biology, Arizona, Bayesian discrete choice model, Colorado River, Ecology, All tags... Geography, Glen Canyon Dam, Grand Canyon, Information Sciences, New Zealand mudsnail, USGS Science Data Catalog (SDC), amphipod crustacean, aquatic Diptera, aquatic biology, aquatic ecosystems, aquatic prey, aquatic worms, biota, black flies, crustaceans, diet, discrete choice models, drift, drifting invertebrate prey, ecological processes, ecology, field sampling, forage, foraging, gut samples, invertebrate drift, invertebrates, mathematical modeling, midges, predation, predator, prey, prey selection, rainbow trout, samples, sampling, worms, Fewer tags

Environmental, biological, and leaf litter decomposition data in the Colorado River downstream of Glen Canyon Dam between 1998 and 2022

Yes, all data values are reasonable and within the valid range for measurement. The data release consists of 15 tabular data files (csv). These data were compiled to compare patterns and potential drivers of leaf litter decomposition in the Colorado River downstream of Glen Canyon Dam between 1998 and 2022. Objective(s) of our study were to compare the breakdown of cottonwood (Populus fremontii), willow (Salix exigua), and salt cedar (Tamarix chinensis) leaves to a previous decomposition experiment from 1998 (Pomeroy et al. 2000) that was conducted in the context of much cooler water temperatures, higher phosphorus concentrations, lower New Zealand mudsnail densities, and salt cedar litter that was unaffected by...

Categories: Data; Tags: Aquatic Biology, Arizona, Colorado River, Ecology, Geography, All tags... Glen Canyon Dam, Hydrology, Information Sciences, Lake Powell, New Zealand mudsnail, Populus fremontii, Salix exigua, Tamarix chinensis, USGS Science Data Catalog (SDC), USGS:6500d7ead34ed30c20580390, Water Resources, air temperature, beetle, biochemistry, biomass, biota, climatologyMeteorologyAtmosphere, community composition, community ecology, cottonwood, data release, decay rates, decomposition, detritus, environment, field data, field experiments, field sampling, growth, inlandWaters, invasive species, invertebrates, laboratory experiments, leaf, leaf litter, leaf litter chemistry, leaf litter mass, leaf mass, leaf nutrient content, leaf pack, litter, nutrient content (water), phosphorus, physicochemical variable, population and community ecology, relative abundance analysis, reservoir storage, river ecosystems, saltcedar, stream discharge, vegetation, warming, water chemistry, water nutrient data, water temperature, willow, Fewer tags

Gross primary production estimates and associated light, sediment, and water quality data from the Colorado River below Glen Canyon Dam

These data were compiled to model the effects of flow regime and bed grain size distributions on rates of gross primary production (GPP) in the Colorado River below Glen Canyon Dam, AZ, USA. The objectives of our study were to quantify daily and weekly scale effects of an experimental flow regime on GPP in the Colorado River. The experimental flow was conducted at Glen Canyon Dam from May-August in 2018, 2019, and 2020 and contrasted steady-low flows on weekend days with business-as-usual hydropeaking flows during weekdays. This data release only contains data through 2019. These data represent daily-scale estimates of GPP, discharge, turbidity, water depth, and canyon shading for eleven reaches on the Colorado...

Categories: Data; Tags: Aquatic Biology, Arizona, Colorado River, Ecology, Geochemistry, All tags... Geography, Glen Canyon, Glen Canyon Dam, Grand Canyon, Grand Canyon National Park, Hydrology, Information Sciences, Limnology, Marble Canyon, Sedimentology, USGS Science Data Catalog (SDC), USGS gage, Water Quality, Water Resources, bed grain size distributions, canyon shading, data release, discharge, dissolved gases, environment, experimental flow regime, field inventory and monitoring, flow regime, gas transfer, grain-size analysis, gross primary production, hydropeaking flows, inlandWaters, light attenuation, northern Arizona, sediment transport, stream discharge, stream-gage measurement, streamflow, surface water quality, turbidity, water depth, water quality, water resources, water sampling, water-quality data, weekly mean discharge, weekly mean gamma, Fewer tags

Consumption rates and total mercury concentration of food items and consumers collected at six sites on the Colorado River in the Grand Canyon, USA, 2007-2009

Consumption rates and total mercury concentration of food items and consumers collected at six sites on the Colorado River in the Grand Canyon. Sites ranged from 0-367 river kilometers downstream of Lees Ferry (AZ, USA). Samples were analyzed for total Hg using cold vapor atomic fluorescence (CVAF, Tekran Model 2600 CVAF spectrometer) following EPA Method 7474. Consumption rate samples were collected quarterly from July 1, 2007 to June 30, 2009. Food items and consumers were collected June 12-28 2008.

Categories: Data; Tags: Colorado River, Exposure, Food web, Grand Canyon, Mercury, All tags... River, USGS Science Data Catalog (SDC), biota, Fewer tags