Date of this Version
The Prairie Naturalist 42(3/4):109-115; 2010, pp 109-115
The central stoneroller (Campostoma anomalum) is a herbivore that can have substantial effects on algal communities, nutrient dynamics, and energy flow in streams. Despite its importance in lotic ecosystems, little is known about its population dynamics in streams of the Great Plains. Our objective was to describe age structure, age-specific mortality, and growth rates of central stonerollers in three Iowa streams. We sampled fish from 41 reaches during June-August 2007. We sampled 466 central stonerollers, of which we aged 192. Fish varied in length from 32 to 130 mm and in age from age 0 to 4 years. Over 75% of the central stonerollers were age 2 or younger. Total annual mortality varied from 53.5 to 65.5% across the 3 streams and averaged 64.4% for all streams. Age-specific mortality was approximately 35% between ages I and 2, but increased to approximately 50% and above for older ages. Central stonerollers grew approximately 75 mm during their first year and approximately 10-20 mm per year in subsequent years. Size structure, age structure, mortality, and growth were similar to other central stoneroller populations in the Great Plains. Our results provide important insight for the management and conservation of streams, and provide a foundation for future research on factors influencing small-bodied, nongame fishes in stream ecosystems.