7326

• UCREFRP Catalog Number: 7326
• Author: McAda, C. W., K. Seethaler and R. S. Wydoski.
• Title: Progress Report June 1, 1974 - October 31, 1975 Investigations of the Movements and Ecological Requirements of the Colorado Squawfish and Humpback Sucker in the Yampa and Upper Green Rivers.
• USFW Year: 1975.
• USFW - Doc Type: Logan, Utah.
• Copyright Material: NO

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MATERIALS AND METHODS
Fish collections were made using a variety of equipment. The
majority of collecting was done using trammel nets varying in lengths
from 26 meters to ninety meters. The small mesh size was 1" sq.. and the
larger-mesh was 10". A 100', 1" mesh, bag seine was also used in
selected areas. Swift water areas were sampled using an electrofishing
boat with a 120-volt generator. The electrofishing boat was quite
ineffective during periods of high water. The effectiveness of the
trammel nets was also reduced at these times due to large amounts of
floating debris. A 15-ft., 1/8 inch bobbinet nylon seine and a
modified scoop shovel with window-screen inserts were-used to collect
small fish.
Sampling sites were largely determined by vehicle access, although
- sampling with the seines was done on several float trips along less
accessible sections of the rivers, and at several other access points.
The primary collecting points (Figure 1) are:
1. Lily Park; the Yampa River from about 4 miles above to 4 miles
. below the mouth of the Little Snake River.
2. Castle Park; a four mile section of the Yampa River located
about i8 miles from its mouth.
3. Echo Park; the confluence of the Green and Yampa Rivers.
4. Island Park; the Green River approximately 13 miles below the
mouth of the Yampa. _
5. Horseshoe Bend; the Green River approximately 15 miles below
the town of Jensen, Utah.
6. Ouray; the confluence of the White and Duchesne Rivers with
the Green.