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surface water and groundwater collections, samples were filtered through a 0.45 micron filter, and split into subsamples, one of which was acidified using nitric acid, and one of which was unacidified. Water samples were kept cold until transfer to the Denver Office Chemistry and Petrography Laboratory of the Bureau of Reclamation. The analyses were carried out under the supervision of Doug Craft. Acidified samples were analyzed using inductively coupled plasma spectrometry for the following metals; V, Si, Zn, Sb, Ag, Al, As, B, Ba, Be, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Pb, Ca, Na, Mg, and K. In addition, Se (selenium) was determined using graphite furnace atomic absorption spectrometry by Barringer Laboratories in Golden, CO. Unacidified samples were analyzed for HCO'3, SOZ'4, and Cl', along with alkalinity, lab conductivity, lab pH, and TDS. The water chemistry data are used for two purposes; (1) to determine if any element occurs in concentrations that could be of biological importance to razorback suckers, and (2) to help identify distinct water sources feeding the wetlands. Water quality standards published by the State of Utah are used in this report as guidelines for elemental concentrations that exceed the numeric criteria for aquatic life (State of Utah 1993). Vegetation patterns were determine to allow us to analyze the major aquatic habitats in the study area wetlands. Five habitats had standing water and were sampled. These are: (1) hardstem bulrush (Schoenoplectus acutus) and broadleaf cattail (Typha latifolia) emergent marsh; (2) submersed aquatic marsh dominated by sago pondweed (Potamogeton pectinatus); (3) alkali bulrush (Bolboschoenus maritimus ssp. paludosus) marsh; (4) riverine backwaters which were unvegetated; and (5) river channel which was unvegetated. Other important habitats on site included cottonwood forests, tamarisk thickets, tall whitetop thickets, and rush meadows. These later habitats were not sampled for invertebrates because they never had standing water during the sample period and could not provide habitat for fishes, although leaf litter from these stands could certainly be an important component of the aquatic food chain for certain stands. For the three marsh types occurring in the Escalante Ranch wetlands, autochthonous organic matter for processing by invertebrates was abundant. Invertebrates were sampled in the water column and benthos for all stations at all sample dates. A 210 µm Nitex covered net, 15.2 cm in diameter, and 182 cm2 in area, with long handle was carefully lowered to the bottom of the water column and allowed to sit for approximately one minute. Then, the net was raised vertically in one very rapid motion and all invertebrates collected in the net were washed using tap water into plastic collection bottles. A 5~ formalin was added to each bottle to 2