PARENT SESSION
Tuesday, August 8, 5:00-6:30 pm
Poster Session 8 - Aquatic ecology
Exhibit Hall, Ballroom Level, Cook Convention Center
Unionid (Mollusca: Bivalvia) assemblage structure of an Ozark river.
Matthews, Mickey*,1, Usrey, Faron2, Seagraves, Sara1, Hodges, Shawn2, Christian, Alan1, 1 Arkansas State University, Jonesboro, AR, USA2 National Park Service, Harrison, AR, USA
ABSTRACT- The Buffalo River, of north Arkansas, is a 153-mile river flowing through the Boston Mountains, Springfield plateau, and Salem plateau of the Ozark Mountains to the White River. America's first National River encompasses much of the river proper, with the National Park Service owning 11% of the watershed and state and federal agencies owning an additional 29%. The objectives of this project are to survey the entire wet length of river, search for endangered and extirpated mussels, and document the mussel assemblages. During 2004 and 2005, 146 miles of the river were qualitatively and quantitatively surveyed resulting in a total of 63 aggregates. Quantitatively sampled mussel aggregates (n=22) resulted in a mean richness of 9.45, ranging from 4 to 15 and a mean density of 6.85 individuals / m2, ranging from 1.33 to 25.64 individuals / m2. Mean aggregate area 277m2 ranging from 54 to 840 m2. Time constrained qualitatively sampled aggregates (n= 41) resulted in a mean richness of 7.77 with a range of 2 to 12. Detrended corresponded analysis (DCA) revealed 4 distinct community types: 1) Ptychobranchus occidentalis, 2) Villosa iris, 3) Cyclonaias tuberculata, and 4) Actinonaias ligamentina that roughly represented species gradients along the river length. Past work listed a total 26 species for the river however only 21 species were identified in this survey with no federally listed species found. Future work includes nutrient recycling based on community types, quantification of exotic bivalve densities, and associating geomorphological characteristics to mussel distribution.
Key words: Freshwater Mussels, Rivers, Aquatic Ecology