Daphnia lumholtzi, a large cladoceran native to Africa, Asia, and Australia, has recently invaded reservoirs of the southern United States. We examined its distribution, history of invasion, and population dynamics in Missouri reservoirs. Surveys detected the species in 7 of 112 reservoirs in 1992 and 11 of 119 reservoirs in 1993. Analysis of quantitative zooplankton samples from two reservoirs over a 7-year period indicated that D. lumholtzi first reached detectable densities in 1990 and persisted during 1991–1993. Population maxima typically occurred in late summer, with the species absent from the plankton during winter and spring. Based on its current distributional patterns, D. lumholtzi appears to be capable of colonizing most reservoirs in the southern regions of North America.

Intensive physical modification of the Missouri River for navigation, flood control, and power generation has dramatically changed the river corridor. Dams, revetments, channelization, and levee construction activities have constrained the river into a single fast, deep channel and disconnected the river from the flood plain. These dramatic hydrological alterations have reduced the available habitat for numerous bird, fish, invertebrate, and plant species. Several native species have declined, leading to their federal listing under the Endangered Species Act. It is widely recognized that recovery of endangered species is primarily dependent on physical habitat rehabilitation. Land acquisition for ecological rehabilitation in the Lower Missouri River has historically been impeded due to the lack of land available from willing sellers and lack of funds and authority. However, this situation changed in 1993 following a severe flood. Flooding broke many levees and scoured numerous deep holes in the flood plain; in addition, thick layers of sand were deposited on numerous crop fields. Subsequently, much flood-altered farmland was willingly offered for sale by private landowners.Much of this land was then purchased by governmental agencies for environmental rehabilitation. Lisbon Bottom is one of several parcels of flood-damaged land that was purchased from willing sellers by the U.S. Fish and Wildlife Service as part of the Big Muddy National Fish and Wildlife Refuge. Lisbon Bottom is a loop bend in the river near Glasgow, Missouri. Flooding at Lisbon Bottom in 1993 and 1995 breeched local levees and created a diverse wetland complex. Lisbon Bottom is managed in a passive manner. The levees have not been rebuilt, and floods and vegetative succession continue to alter the landscape. A side-channel chute was formed by further flooding in 1996 and 1997. The diversity of wetland types and the continued connection to the river make Lisbon Bottom an excellent natural laboratory for the study of flood-plain wetland processes and the use of flood-plain wetlands by biota.This study had 3 objectives: 1) quantify spatial and temporal distribution of biota in aquatic habitats of Lisbon Bottom in relation to changes in hydrological variables that are associated with the spring flooding regime, 2) document biological responses as they are related to habitat dynamics, and 3) analyze and interpret these results to provide managers with information necessary to develop management strategies for Lisbon

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We report first records on occurrence of the midge genus Telopelopia Kieffer in wadeable streams in Missouri based upon aquatic macroinvertebrate community samples collected during years 2010 through 2019 from 30 reaches of 15 wadeable streams within three Ecological Sections of the state. Physical habitat and water quality characteristics of the reaches where Telopelopia was found to occur are also provided.