Predictability of littoral-zone fish communities through ontogeny in LakeTexoma, Oklahoma-Texas, USAMichael A. Eggletona,b, Raul Ramireza,c, Chad W. Hargravea, Keith B. Gidoa,d, Jason R. Masonere,f,Gary D. Schnella,g& William J. Matthewsa,g,haSam Noble Oklahoma Museum of Natural History, University of Oklahoma, 2401 Chautauqua Avenue,Norman, OK 73072, U.S.A.bCurrent address: Aquaculture/Fisheries Center, University of Arkansas at Pine Bluff, 1200 N. UniversityDrive, Box 4912, Pine Bluff, AR 71601, U.S.A (e-mail: [email protected])cCurrent address: Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville,IL 62026, U.S.A.dCurrent address: Division of Biology, Kansas State University, Ackert Hall, Manhattan, KS 66506, U.S.AeEnvironmental Protection Agency, Robert S. Kerr Environmental Research Laboratory, P.O. Box 1198, Ada,OK 74821, U.S.A.fUS Geological Survey, Water Resources Division, 202 NW 66th Street, Building 7, Oklahoma City, OK73116, U.S.A.gDepartment of Zoology, University of Oklahoma, Norman, OK 73019, U.S.A.hUniversity of Oklahoma Biological Station, HC 71, Box 205, Kingston, OK 73479, U.S.A.Received 3 July 2003 Accepted 25 August 2004Key words: reservoirs, littoral-zone fishes, larval fishes, environmental gradientsSynopsisWe sampled larval, juvenile and adult fishes from littoral-zone areas of a large reservoir (Lake Texoma,Oklahoma-Texas) (1) to characterize environmental factors that influenced fish community structure, (2) toexamine how consistent fish–environment relationships were through ontogeny (i.e., larval vs. juvenile andadult), and (3) to measure the concordance of larval communities sampled during spring to juvenile andadult communities sampled at the same sites later in the year. Larval, juvenile and adult fish communitieswere dominated by Atherinidae (mainly inland silverside, Menidia beryllina) and Moronidae (mainlyjuvenile striped bass, Morone saxatilis) and were consistently structured along a gradient of site exposure toprevailing winds and waves. Larva l, juvenile and adult communities along this gradient varied from ath-erinids and moronids at highly exposed sites to mostly centrarchids (primarily Lepomis and Micropteru sspp.) at protected sites. Secondarily, zooplankton densities, water clarity, and land-use characteristics wererelated to fish community struc ture. Rank correlation analyses and Mantel tests indicated that the spatialconsistency and predictability of fish communities was high as larval fishes sampled during spring wereconcordant with juvenile and adult fishes sampled at the same sites during summer and fall in terms ofabundance, richness, and community structure. We propose that the high predictability and spatial con-sistency of littoral-zone fish es in Lake Texoma was a function of relatively simple communities (dominatedby 1–2 species) that were structured by factors, such as site exposure to winds and waves, that varied littlethrough time.Environmental Biology of Fishes (2005) 73: 21–36  Springer 2005IntroductionFor fishes, their ‘environment’ encompasses mul-tiple factors that are both abiotic (e.g., hydrology,habitat, water quality) and biotic (e.g., presence ofother species, levels of primary production;Matthews 1998). Different life-history stages (e.g.,larval vs. juveni le or adult) may be influenced bydifferent environmental factors. For instance,springtime hydrology and associated turbiditymay be important determinants in the local dis-tribution of larval fishes (e.g., Matthews 1984,Mitzner 1991), whereas the structures of juvenileor adult fish communities may be more related tosite-specific environmental factors, habitat diver-sity, or interactions with predators (Tonn &Magnuson 1982, Lyons & Magnuson 1987,Benson & Magnuson 1994, Lienesch & Matthews2000, Marsh-Matthews & Matthews 2000). Iden-tifying which environmental factors are importantin the structuring of fish communities and howthey vary through ontogeny may increase under-standing of fish community dynamics.Reservoirs represent ideal systems to study fish–environment relationships. Reservoirs exhibitstrong spatial gradients with uplake regions beingmore riverine and downlake regions near the dambeing more similar to natural lakes (Thornton et al.1990, Gido et al. 2002). As a result, many biotic(e.g., fish communities) and abiotic (e.g., waterclarity or nutrients) characteristics in reservoirs varypredictably along these gradients. Fish abundance,biomass, and species composition often exhibitpredictable patterns along these gradients (Gelwick& Matthews 1990, Gido & Matthews 2000, Lie-nesch & Matthews 2000, Gido et al. 2002), thoughprevious studies have been restricted to adult fishes.However, in some cases, local factors relative to aparticular reach of shoreline (e.g., Lienesch &Matthews 2000, Gido et al. 2002) or landscape-levelfactors associated with a particular drainage basin(e.g., Larsen et al. 1986, Schloesser 1991, Williamset al. 2002 reported from streams) may overridegradient-type variables in structuring reservoircommunities. The interplay of these mechanismsresults in a diversity of environmental conditions,which makes reservoirs unique study systems forassessing fish–environment relationships.Our objectives were (1) to characterize environ-mental factors that influenced fish communitystructure, (2) to examine how consistent fish–envi-ronment relationships were through ontogeny, and(3) to measure the concordance of larval fish com-munities sampled during spring to juvenile andadult fish communities sampled at the same siteslater in the year. We focused on littoral–zone com-munities because they are an important functionalcomponent of aquatic systems (Northcote 1988),but are much less studied in reservoirs becausecommunities are dominated by smaller-bodiedspecies of no commercial or recreational interest.We made assessments of larval, juvenile and adultfish communities over a 6-month period during2001. Larval communities were assessed monthlyfrom March through June; we assessed juvenile andadult communities in July and October. We ex-pected that juvenile and adult fish communitieswould be structured mostly around local habitatfeatures because of their more diverse life-historyrequirements. Unlike larval fishes, many of thesefishes are reproductively active, feed on a widevariety of foods (e.g., algae, fish, zooplankton, andbenthic invertebrates), and require