The effects of green sunfish on the distribution, abundance and habitat use of gila chub in Sabino Creek, Arizona
Agriculture, Forestry and Wildlife.
Agriculture, Fisheries and Aquaculture.
AdvisorMatter, William J.
MetadataShow full item record
PublisherThe University of Arizona.
RightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
AbstractGila chub (Gila intermedia) were at lower densities in areas of Sabino Creek with green sunfish (Lepomis cyanellus) than areas without sunfish. No young-of-year (YOY) chub were observed in pools where densities of sunfish were reduced by about 90% or in control pools, but YOY chub were abundant in upstream areas without sunfish. The microhabitat selected by YOY chub was nearly identical to that selected by sunfish (7.5 cm, TL). In predation experiments, sunfish (7.5 cm, TL) consumed YOY chub (2.5 cm, TL). The absence of YOY chub in areas with sunfish may, in part, be due to predation by small sunfish. In winter, chub use of microhabitat did not differ in areas with and without sunfish. In summer, chub used faster currents, areas farther from cover and shallower depths in areas with than without sunfish. In summer, niche shifts by chub may be a response to avoid negative interactions with sunfish.
Degree ProgramGraduate College
Renewable Natural Resources