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Invertebrate Spatial Distribution At all stations water column and benthic-samples were collected to quantify invertebrate numbers in each strata. Zooplankton comprised a greater percentage of invertebrates present in the bulrush community and benthic invertebrates comprised a greater percentage in the river, backwater and open water communities .(Figure 24). Benthic invertebrates. were absent in :all flooded willow samples throughout the season. In general, -water column invertebrates were abundant in the wetland- -. communities but nearly absent in backwater and river communities. Mean water column invertebrates densities L'1 -were highest in-the bulrush followed by the open water, flooded willow, and backwater communities (Figure 25). The river community was nearly devoid of water column invertebrates. Benthic invertebrate densities were highest in the open water followed by the bulrush, river, and backwater communities. No invertebrates were collected in flooded willow benthic samples.- The wetland communities produced greater numbers of water column and benthic organisms-than did the-river communities. The importance-of benthos to overall river and backwater invertebrate community production-and biomass cannot be emphasized enough, as these. invertebrates are much more. numerous than water-column invertebrates. Cladocera were most abundant- in the bulrush communities (~` -while Copepoda were most abundant in the open water communities • (Figure 26). Chironomids, insects other .than Chironomids, and all other invertebrates (i.e. Gastropods, Nematoda, Hydra, and- Protozoa) all, reached their greatest densities in bulrush communities. The bulrush community also had the highest species richness to the :taxonomic level identified-with alI five categories being represented. The open water and flooded willow communities were represented by four taxonomic groups. Cladocera and Copepoda were-the only water column invertebrates in the- .:backwater community while the river Community supported only,. 'Chironomids and other insects. 43