7993

• UCREFRP Catalog Number: 7993
• Author: Mabey, L. W.
• Title: Planktonic and Benthic Microcrustaceans from Floodplain and River Habitats of the Ouray Refuge on the Green, River, Utah - Master's Thesis.
• USFW Year: 1993.
• USFW - Doc Type: Brigham Young University,
• Copyright Material: NO

magnification. Plankton samples were processed by either counting the entire sample
or by sub-sampling with a Hensen-Stempel pipet.
We determined the number of benthic cores and subsamples of the plankton tows
to process using procedures recommended by Elliot (1977) where n=s2/D'x-bare and
D is an index of precision. For this study D was set at .1 or a 10 % level of
acceptable error. The numbers of samples/subsamples processed was calculated at
95% confidence limits with a 10% acceptable error. Samples/subsamples were then
processed until the sample size calculated from Elliot's formula was less than or equal
to the actual number of samples processed. A1150 benthic cores and all five plankton
tows were processed for the river and backwater sites because the calculated n was
never less than 50 nor were plankton densities high enough to make subsampling
necessary.
Identifications
All life stages of Copepods were quantified. Naupliar stages were not further
identified. Copepodids were identified to suborder and adult Copepods were identified
to species. Cladocera were identified to species or categorized as unidentified.
Copepods were dissected to aid in identification. Cladocerans and copepods were
mounted in glycerin jelly on glass slides. Organisms were then identified with the aid
of an inverted light microscope at 125x-400x magnification. Identifications were made
according to the keys of Edmonson (1959) and Pennak (1989).
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