10:15 VARIATION AND COVARIATION IN THE STRUCTURE OF BENTHIC MACROINVERTEBRATE COMMUNITIES AND THEIR ENVIRONMENTS AT TWO SPATIAL SCALES IN A TROPICAL STREAM.
L. Boyero¹, A. García-Valdecasas¹, and R.C. Bailey². ¹Departamento de Biodiversidad y Biologia Evolutiva, Museo Nacional de Ciencias Naturales, Madrid, Spain, ²Department of Zoology, The University of Western Ontario, London, Ontario, Canada N6A 5B7

10:30 ANALYSIS OF ALGAL COMMUNITIES THROUGHOUT A TROPICAL WATERSHED.
C.E. DeJaco¹ and R.J. Stevenson². ¹Dept. of Biology, University of Louisville, Louisville, KY 40292, ²Dept. of Zoology, Michigan State University, East Lansing, MI 48824-1115

10:45 THE INFLUENCE OF HYDROLOGICAL SEASONALITY ON BACTERIAL PRODUCTION AND ABUNDANCE IN LOWLAND RIVERS OF THE ORINOCO BASIN, VENEZUELA.
M.M. Castillo. School of Natural Resources and Environment, The University of Michigan, Ann Arbor, MI 48109-1115

11:00 THE IMPORTANCE OF BENTHIC ALGAE TO AQUATIC FOOD WEBS IN AUSTRALIAN STREAMS AND RIVERS.
S.E. Bunn¹, P.M. Davies², and J.W. Udy¹. ¹Cooperative Research Centre for Freshwater Ecology, Griffith University, Nathan, Queensland, 4111, Australia, ²Department of Zoology, The University of Western Australia, Nedlands, Western Australia 6907

11:15 RESPONSE OF STREAM EPILITHON AND HERBIVORES TO A LIGHT GRADIENT IN EXPERIMENTAL CHANNELS.
P.M. Kiffney. National Marine Fisheries Service, Northwest Fisheries Science Center, 2725 Montlake Blvd. East, Seattle, WA 98112

11:30 EFFECTS OF FOREST CANOPY COVER ON TROPHIC LEVEL BIOMASS PATTERNS IN STREAM FOOD WEBS.
B. VandenEeden and A. Turner. Department of Biology, Clarion University, Clarion, PA 16214

11:45 USING STABLE ISOTOPES TO COMPARE PRISTINE AND DISTURBED FOOD WEBS IN CUATRO CIENEGAS, MEXICO.
J.C. Marks¹, B.A. Hungate¹, and D.A. Hendrickson². ¹Department of Biology, Northern Arizona University, Flagstaff Arizona, USA 86011, ²Texas Natural History Collections, University of Texas, Austin, TX USA 78758-4445