The macrobenthic fauna of the Rhône River below Lake Geneva was studied between 1983 and 1993 to describe patterns of longitudinal and temporal community changes. Sampling was based upon the use of artificial substrates in 11 stations. The confluence with the Arve (an alpine tributary) is the first source of faunal discontinuity, both in terms of species and feeding group composition. The Verbois hydropower plant is the second longitudinal disruption. From a temporal point of view, the construction of the Seujet hydropower plant was a major source of faunal fluctuation. After this event, and until the end of the study, lenitophilous taxa increased to the detriment of rheophilous taxa.

Historically, the Kissimmee River meandered over an extensive floodplain wetland. In response to catastrophicflooding and settlement pressures in Central Florida, the Kissimmee was channelized, converting the complex, braidedchannel into a straightened canal. The result has been a sharp decrease in fringing wetland habitat and associatedbiota. Soon after channelization was completed, environmental concerns prompted the State of Florida tostart examining options for restoration to reestablish the river's natural hydrology and restore lost wetland habitat.The grass shrimp, Palaemonetes paludosus has been identified as a keystone invertebrate species in this system.This study was designed to examine its distribution, diel movement, and growth within the two dominant macrophytecommunities of the Kissimmee River riparian marsh: Nuphar and Polygonum. Results indicated that grassshrimp were more abundant in Polygonum beds. This species also showed no well-defined diel migration, althoughwe found a significant vertical pattern in some instances. Palaemonetes paludosus growth was highest on periphytonand Polygonum leaves. Grass shrimp distribution may be explained by their decreased susceptibility to predationbecause of the higher habitat complexity inherent in Polygonum beds.