1. Sites were selected based on landowner relations and potential for restoration by The Nature Conservancy. They were then grouped based on level of impact: high (2 and 3C) and low (3A, 3B, and 8). Effects of Physical Habitat Alteration on Fish Communities in the Middle Fork Saline River, AR. Chad Blackburn, Lainy Burkard, Leslie Patrick, Sarah Scroggins, Richard Walker Faculty Mentor: Ginny Adams Environmental Science, University of Central Arkansas, Conway, AR 72035 Riparian vegetation is a vital element of aquatic ecosystems, providing bank stabilization, topsoil filtration, habitat structure canopy cover, and organic input necessary for aquatic species. The Middle Fork Saline River provides an interesting model to examine impacts of urban development and human population growth on aquatic systems due to its close proximity to Hot Springs Village. The resulting loss of riparian zones, sedimentation, and embeddedness in the river have negatively altered the aquatic ecosystem. The objectives for this study were to examine potential biotic and physical habitat modification associated with disturbance. This project was conducted in conjunction with The Nature Conservancy to provide repeatable, baseline data for a planned restoration project. Methods Results Low Impact: High Impact: Sites 2 and 3C Sites 3A, 3B and 8 Mean Habitat Score: Mean Habitat Score: 96.34 ± 5.28 52.22 ± 4.42 P < 0.0001 Figure 1. Total rank abundance of fish communities for all five sites in the Middle Fork Saline River. A total of 2,197 individuals, encompassing 8 families and 23 fish species were collected. The two most abundant species found at all sites were Central Stoneroller and Bigeye Shiner. T-test: Ouachita Madtom abundance P= 0.0244 Low impact (2 & 3C) High impact (3A,3B,& 8) Mean: 7.43 + 1.36 Mean: 2.46 + 1.20 Acknowledgements We would like to thank Joy DeClerk from The Nature Conservancy, Ruth Bland, Kerri McCabe, Kate Howard, Luke Driver, and Tommy Inebnit for support in the field. We would also like to thank the land owners for allowing us to access the study sites found on their land and Drs. Ginny and Reid Adams for assistance and equipment. Introduction At each site a standard riffle habitat area (for an average total of 105 m per site?) was sampled using a combination of electroshocking, dip nets, and block-nets. Fishes were collected in the field and returned to the laboratory for identification. Discussion The Nature Conservancy categorized sites based on level of impact using quantitative methods. In our study we implemented more qualitative methods to support categorization of high and low impacted sites. We found ubiquitous species (e.g. Central Stoneroller and Bigeye Shinner) as well as unique, sensitive species (e.g. Ouachita Madtom and Banded Darter). The Ouachita Madtom is an endemic species whose abundance was significantly lower in high impact sites. Based on our data, The Nature Conservancy’s habitat restoration is expected to increase the Ouachita Madtom’s abundance. These baseline data will be utilized by the Nature Conservancy for a comparison of fish communities during and after restoration on the Middle Fork Saline River. High Impact SiteLow Impact Site Redspot Darter Striped Shiner Bluntnose Minnow Northern Studfish Longear Sunfish Greenside Darter Central Stoneroller Bigeye Shiner