Date of Graduation

Summer 2011


Master of Science in Biology



Committee Chair

Daniel Beckman


duskystripe shiner, otolith, growth, age, stream order

Subject Categories



Research was conducted to describe the variability in growth and age structure of the duskystripe shiner (Luxilus pilsbryi) along a stream gradient. Duskystripe shiners (n= 600) were sampled from eleven sites representing 4 stream orders. Fish were collected in the spring of 2010 using seining techniques, and the physical assessment of fish and habitat was performed within 24 hours after collection. Shiners were categorized into populations based on stream order for statistical analysis. Ages were determined using the asterisci otoliths (inner ear bones), based on previously validated techniques. Significant correlations existed between stream order and fish growth rate, condition, and longevity. Upstream portions of the river contained older shiners than downstream portions. Male and immature shiners had faster growth rates in upstream portions of the river. Female gonadosomatic indices were higher in upstream portions of the river. Shiners had higher condition factors in upstream portions of the river. Habitat conditions were relatively similar along the river. The findings suggest that duskystripe shiners in headwaters are better able to use resources to enhance their physical condition compared to fishes in higher order stream regions.


© Nathan Michael Recktenwald

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