Stochasticity in Structural and Functional Characteristics of an Indiana Stream Fish Assemblage: A Test of Community Theory

TitleStochasticity in Structural and Functional Characteristics of an Indiana Stream Fish Assemblage: A Test of Community Theory
Publication TypeJournal Article
Year of Publication1982
AuthorsGrossman, G. D., Moyle P. B., & Whitaker, Jr. J. O.
JournalThe American Naturalist
Volume120
Issue4
Pagination423-454
Date Published10/1982
ISSN00030147
AbstractIn general, ecological assemblages and communities appear to be regulated primarily by either deterministic or stochastic processes. It is currently important to quantify the relative frequencies of these two types of assemblages since most ecological theory is applicable only to deterministic systems. We attempted to distinguish the mechanism regulating species abundances and trophic structure in an Indiana stream fish assemblage. Samples collected over a 12-yr period were separated by season (spring, summer, and autumn) and species were then assigned to a trophic group based on published dietary data. Analyses showed a total lack of persistence for the ranks of species abundances and the ranks of trophic groups for all seasons. Consequently, we conclude that this assemblage is probably regulated by stochastic factors. This finding is concordant with many other studies which have documented the substantial effects of environmental unpredictability (i.e., floods and droughts) on other stream taxocenes.
URLhttp://www.jstor.org/stable/2461070