Effects of Crayfish Presence and Substrate Size on Benthic Populations in Little Niagara Creek

Abstract

A current concern for many freshwater bodies is the rising number of invasive Rusty Crayfish (Oroconectes rusticus) an aggressive species that can potentially harm the freshwater ecosystem they inhabit. This can be done by directly praying upon microorganisms, (Charlebois & Lamberti 1996, Keller & Ruman 1998) or by competing for resources necessary to other species. In our study, we aimed to assess whether there is an inverse relationship between crayfish presence and the abundance of streambed (benthic) organisms in Little Niagara Creek, specifically in relation to substrate size. We hypothesized that the greater interstitial space among large-sized substrate would allow crayfish better accesses to prey, lowering the amount of specimens in the benthic community.