The Influence of Environmental Predictability/Disturbance Characteristics on the Structure of a Guild of Mountain Stream Insects

Publisher Website
Google Scholar
Abstract
Resource overlap in the scraper/collector-gatherer guild along temporal, trophic and microspatial niche dimensions was determined at two sites in the Upper Colorado River, The amount of resource overlap within the scraper/collector-gatherer guild in a predictable, benign regulated section of the river was compared with the amount of overlap within the scraper/collector-gatherer guild of a less predictable, frequently disturbed free-flowing section. Thirty years of daily flow records, were used to determine predictability and frequency of disturbance events. Trophic, temporal and microspatial overlap between the two guilds was not significantly different. There was no evidence to support the hypothesis that resource overlap should be reduced or more regularly spaced in guilds inhabiting predictable benign environments.