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conductivity, DO and temperature at sample times using a ICM water analyzer Model 51601. For well samples, water was pumped using a hand pump until several well volumes had been removed and the water ran clear. surface and ground water samples were collected for chemical analysis from these same stations. For surface and ground water 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, A1, 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. Unacidif:ied samples were analyzed for HCO'3, SOZ'4, and C1', along with alkalinity, lab conductivity, lab pH, and TDS. At the Ouray study area water chemistry data are used to determine if any element occurs in concentrations that could be of biological importance to razorback suckers. At the other study areas a much more complete surface and ground water investigation was conducted and water chemistry was used to help identify distinct water sources feeding the wetlands. This was not done at Ouray. 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) submersed aquatic marsh dominated by sago pondweed (Potamogeton pectinatus); (2) hardstem bulrush (Schoenoplectus acutus) and broadleaf cattail (Typha latifolia) emergent marsh; (3) Fremont cottonwood (Populus fremontii) riparian forests; (4) riverine backwaters which were unvegetated; and (5) river channel which was unvegetated. A number of other important habitats on site included tamarisk thickets, tall whitetop thickets. 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 submersed aquatic and bulrush marsh types occurring in the Ouray 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 um 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 2