Macroinvertebrate Communities in Restored and Natural Slough Wetlands: Evaluation of Restoration Practices in the Central Platte River Valley.

Wetlands in the central Platte River basin of Nebraska provide numerous ecosystem services, but these systems have been degraded through drainage for agriculture and increasing river regulation. Restoration is currently a common means of increasing wetland area in this region, but little is known about the success of these restorations. We quantified macroinvertebrate abundance, biomass, and community structure in restored wetlands ranging in age from 5-11yrs old and compared them with proximal natural systems to assess success. Analyses of seasonal samples showed that total macroinvertebrate abundance, biomass, richness, and diversity were similar between restored and natural wetlands. However, biomass values reflected some differences in community and functional structure. Whereas insects constituted most biomass in natural systems (55%), mollusks, mostly Physella and Fossaria, dominated biomass (61%) in restorations. In natural wetlands, collector-gatherers and predators contributed most to mean biomass (~29% each), followed by a relatively even distribution of herbivores, collector-filterers, and scrapers. In contrast, collector-gatherers contributed most to mean biomass in restored wetlands (47%), followed by scrapers (43%) and predators (13%). Although total values and most abundance-based metrics suggested that macroinvertebrate communities had recovered in restored wetlands, biomass patterns indicate that recovery of communities and function is not complete.