Rainbow trout diet and invertebrate drift data from 2012-2015 for the Colorado River, Grand Canyon, Arizona
Data for journal manuscript: As the prey thickens: rainbow trout select prey based upon width not length
Dates
Publication Date
2021-07-30
Start Date
2012
End Date
2015
Citation
Yackulic, C.B., Dodrill, M.J., and Kennedy, T.A.., 2021, Rainbow trout diet and invertebrate drift data from 2012-2015 for the Colorado River, Grand Canyon, Arizona: U.S. Geological Survey data release, https://doi.org/10.5066/P923AX7C.
Summary
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 of 5 primary taxa; two [...]
Summary
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 of 5 primary taxa; two small aquatic Diptera: black flies (Simuliium sp.) and midges (family Chironomidae), an amphipod crustacean (Gammarus lacustris), New Zealand mudsnail (Potamopyrgus antipodarum), and aquatic worms (Tubificidae and Lumbriculidae). The U.S. Geological Survey collected and processed 784 individual drift samples and 1,028 diet samples following the methods described in Kennedy et al. (2014). To analyze these data, we developed a Bayesian discrete choice model, the structure of which is described in Dodrill et al. (Larger Work Citation). These data are compiled by sampling trip and reach. Additionally, a subset of invertebrates from each sample were measured to the nearest mm in length to characterize their size distribution.
These data were used to fit a Bayesian discrete choice model that estimates prey selection patterns given attributes of both predator and prey. Drift-feeding fish, such as rainbow trout, are typically considered size-selective predators. The collections of drift and diet data allow for the quantification of the strength of prey size selection. Other patterns of prey selection could also be quantified, such as the selection or avoidance of individual prey taxa or life-stages. The discrete choice model was coded in the modeling software Stan, which is provided in the supplemental data associated with Dodrill et al. (Larger Work Citation).
Rights
The author(s) of these data request that data users contact them regarding intended use and to assist with understanding limitations and interpretation. Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty.
