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1 ' damselflies (Ischnura sp.), diving beetles (Dytiscus sp.), water striders (Gerris sp.), backswimmers ' (Notonecta sp.), water boatmen (Corixa sp.) and mosquito fish (Gambusia affinis). The abundant dragonflies (Libellula sp.) feed on mosquito larvae and ' adults. Although predator numbers are high in the Preserve, small isolated pockets of mosquito habitat are inaccessible to larvae predators. These microhabitats are wide spread and abundant in the ' Preserve, often occurring within the large stands of bulrush. Predators found within the Preserve that feed on adult mosquitoes include several species of birds, ' particularly swifts, swallows, and nighthawks. Several species of bats are also known to forage within the Preserve. ' There is no clear understanding of how the Preserve mosquito habitat contributes to mosquito numbers found outside of the Preserve. Mosquito habitat exists ' throughout Moab Valley including irrigated agricultural fields and in residential areas, where any standing water is potential mosquito habitat. The Moab Mosquito ' Abatement District is working with TNC to include the Preserve in a new mosquito management plan for the Moab area. ' Conclusion: Mosquito control is a key public issue in managing the Preserve for razorback sucker recovery. ' 2. Fish Abundant non-native fish are present in the Preserve wetlands. Carp (Cyprinus carpio) constitute the largest ' portion of fish in terms of biomass. Mosquito fish populations were very low after the flood waters receded in ' June, but numbers exploded by the end of summer. Large numbers of mosquito fish survived the winter of 193-194. Seining in the south ponds in up to 18 inches of water revealed the presence of green sunfish (Lepomis cyanellus), fathead minnows (Pimephales promelas), and red shiners ' (Notropis lutrensis). ' Conclusion: Non-native fishes are believed to be a major limiting factor to razorback sucker larvae survival. Non- native fish populations will be difficult to control within the Preserve. A more thorough characterization of the resident fish community will provide critical information needed for future management decisions. 22