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Josh Korman

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These data were compiled to fit an integrated population model of brown trout in the Glen Canyon Reach of the Colorado River and test different hypotheses regarding the driver of brown trout population dynamics. Also, data were compiled as inputs for a model to simulate population dynamics and species interactions among brown trout, rainbow trout and humpback chub in the Colorado River between Glen Canyon Dam and the confluence of the Colorado River and the Little Colorado River.
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These data are the primary data used to model rainbow trout growth in Glen Canyon. Fish growth data were collected from nighttime boat electrofishing field campaigns conducted five to six times per year in April, July, September, and January, from April 2012 through November 2021 for a total of 9798 observations of mark-recapture-based growth. Sampling was conducted in a five km reach in the lower portion of the Glen Canyon tailwater (3.7-8.9 km upstream of Lees Ferry, AZ). Two nights of sampling occurred on each trip, with the central 2-3 km of the reach sampled on both nights. After capture, fish were kept in aerated 40-L buckets and transported to a central processing location. Groups of 10-15 fish were anesthetized...
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These data were compiled to test hypotheses regarding drivers of movement of brown trout. Objectives of our study were to test whether the degree of movement varied in response to placement of a weir in Bright Angel Creek, fall timed flooding events, or simply seasonal changes. These data represent summarized capture histories of brown trout in terms of states based on physical locations, data on removal efforts in Bright Angel Creek, and summaries of effort in the mainstem Colorado River. These data were collected at several locations along the Colorado River in Glen and Grand Canyon, including Bright Angel Creek from 2011 to 2018. These data were collected by U.S. Geological Survey, National Park Service, and...
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These data were compiled to support stranding risk modeling of young-of-year rainbow trout in Glen Canyon resulting from fluctuating flows from Glen Canyon Dam, called Trout Management Flows (TMFs). The objective of our study was to evaluate the stranding risk associated with different TMFs. We used the results of a 2-dimensional hydrodynamic model (Wright and others, 2024) as input to a rainbow trout stranding model and described in the associated Larger Work Citation. This data table was developed to link the data output tables of Wright and others (2024) and the trout stranding model to a commonly used and standardized measure of distance along the Colorado River between Glen Canyon Dam and Lees Ferry, AZ (Gushue...
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Using a bioenergetic model, demographic data for the Rainbow Trout (Oncorhynchus mykiss) population were compiled and used to estimate total prey consumption in the Colorado River, Glen Canyon , AZ. Additionally, other data including invertebrate diet, drift, and benthic measurements were used to make generalized estimates of daily production rates for the most common benthic invertebrate taxa. The primary objectives were to test a set of hypotheses regarding proximate and distal drivers that were regualating secondary production of invertebrate prey in Glen Canyon. These production estimates represent an estimate of aggregate prey items that include Chironomidae and Simulium arcticum [complex]), as well as amphipods...
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