Ecology of the Sand Roller (Percopsis transmontana) in a lower Snake River Reservoir, Washington

Northwestern Naturalist
By: , and 



The Sand Roller (Percopsis transmontana), has not been abundant in the Snake River since it was first found in the system in the 1950s, but its population has apparently increased in recent years. As a result, we initiated a study to better understand its ecology in habitats of Lower Granite Reservoir. From November 2014 to October 2015, Sand Rollers were present along shorelines, with peak abundance being observed during spring months. Logistic regression analyses showed that Sand Rollers were more likely to be present in shoreline habitats at temperatures ≤18.4°C. Fish were found over a range of substrates, with the lowest odds of fish presence being associated with riprap, which is common in hydropower reservoirs. From length-frequency analysis, we suggest that Sand Roller spawning occurs primarily in May and early June. Assessment of Sand Roller diets found dipteran (chironomid) larvae and pupae were the most important prey consumed by all sizes of Sand Rollers, but Opossum Shrimp (Neomysis mercedis) were also prominent in diets of larger fish in shoreline and offshore habitats. At a time when the populations of so many native species are in decline, the increase of the Sand Roller population in the lower Snake River represents a positive, yet curious occurrence.

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Publication type Article
Publication Subtype Journal Article
Title Ecology of the Sand Roller (Percopsis transmontana) in a lower Snake River Reservoir, Washington
Series title Northwestern Naturalist
DOI 10.1898/NWN16-25.1
Volume 98
Issue 3
Year Published 2017
Language English
Publisher Society for Northwestern Vertebrate Biology
Contributing office(s) Western Fisheries Research Center
Description 12 p.
First page 203
Last page 214
Country United States
State Washington
Other Geospatial Lower Granite Reservoir, Snake River
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