7153

• UCREFRP Catalog Number: 7153
• Author: Holden, P. B.
• Title: Study of the Habitat Use and Movement of the Rare Fishes in the Green River, Utah.
• USFW Year: 1978.
• USFW - Doc Type: Logan, Utah.
• Copyright Material: NO

when it clogged the seine and firm silt when it did not clog the
seine. Temperatures were taken with hand-held pocket thermometers.
Other salient features of the habitat were noted. In addition, a
sketch of the river in the vicinity of the sample was drawn to
show the relative size and placement of the habitat sampled. All
sampling sites were marked on U.S.G.S. quadrangle maps.
Fish sampling included seining, electrofishing, and use of
a fry shovel (Vanicek, 1967), although seines were used most of
the time because emphasis was on small fish. An attempt was made
to sample individual habitats where physical components were es-
sentially the same. For example, a seine haul would not be made
through part of a run and into an eddy since it would have been
impossible to determine in which habitat type the fish were actu-
ally caught. Fishes were enumerated and total length measurements
taken of sufficient numbers to produce length/frequency relation-
ships and provide an estimate of size (age) classes. Most fishes
were returned unharmed to the location of capture. A reference
collection of most of the species caught was field preserved in
10% formaldehyde and later transferred to 40% isopropyl alcohol.
Rare fishes of sufficient size, usually over 100 mm TL, were
tagged with green plastic, numbered fingerling tags (3/8" x 1/8")
that were sewn to the fish just below the dorsal fin with two-
pound test monofilament line. Juvenile squawfish less than 100mm
were marked by clipping the end of the anal fin.

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