9323

• UCREFRP Catalog Number: 9323
• Author: Cooper, D. J. and C. Severn.
• Title: Wetlands of the Ouray National Wildlife Refuge, Utah
• USFW Year: 1994.
• USFW - Doc Type: Hydrology, Water Chemistry, Vegetation, Invertebrate Communities, and Restoration Potential.
• Copyright Material: NO

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. Formalin was added to each bottle to
preserve the organisms. Three water column invertebrate samples
were collected from each sample station for each sample date.
Water depth was measured for each sample and the depth was
multiplied by the sample net area to determine the volume of
water sampled. Data for Cladocera and Copepoda are the sum of
three size classes due to the relatively small numbers of
organisms smaller than 0.2 mm and larger than 0.5 mm.
Benthic samples were collected with a piston core sampler
which was 29 cm2 in area. Samples included only the top 2 cm of
sediment, making each sample 58 cm3 by volume. After placing the
sample in a zip-lock plastic bag, formalin was added for
invertebrate preservation. Only one sample was collected from
each station on each sample date because we thought that picking
invertebrates from this mud would be extremely labor intensive.
However, the sediments proved to be largely of coarse-textured
material which could be sorted with sieves. Benthic data is
presented in graphs in both number L-1, for comparison to the
water column data, and in more traditional terms of number m'2.
All data for all parameters sampled are summarized here and the
data presented in appendices.
No quantitative vegetation data was collected because of
time constraints. This information would have added somewhat to
our analysis of landscape patterns in the study area, but we did
not feel it would be a critical component to evaluating the
capability for supporting fishes.
One of the goals of our study was to determine how the Ouray
wetlands function today, and how they may have functioned in the
past. By function we mean its present and past hydrologic
regime, flood characteristics, sediment movement, water quality,
vegetation, and habitat for fishes and other wild animals.
Portions of this site retain their natural characteristics,
particularly Wyasket Lake and areas of riparian cottonwood
gallery forests. However, many areas have undergone tremendous
changes due to dike construction to restrict the extent of
flooding and the conversion of natural floodplain lakes and
wetlands into managed wetlands controlled by berms and which
receive water pumped from the Green River. Other areas, such as
Old Charlie Wash have gates which allow much of the water body to
be drained.
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