8091

• UCREFRP Catalog Number: 8091
• Author: Miller, W. H., et al.
• Title: White River Fishes Study
• USFW Year: 1982.
• USFW - Doc Type: Final Report.
• Copyright Material: NO

Several boat sizes were used, but the best adapted units for
general river use were a 16 ft (4.9 m) flat bottom boat powered with a
20 hp jet drive outboard for higher water stage from April through June
and a 17 ft (5.18 m) canoe for long distance radiotelemetry in low
water.
Special Investigations
Abundance and Distribution of Young Colorado Squawfish
r The Vernal Field office initiated a special investigation in the
late summer-early fall of 1979 on the Green River to obtain information
about early life history of Colorado squawfish. In 1981, a similar
investigation was initiated on the White River. Directed toward "filling
in" needed information not obtained by the standardized sampling pro-
gram, this special effort was designed to evaluate the distribution and
abundance of young-of-the-year (YOY) Colorado,squawfish. Collections
were made from Rio Blanco Lake in Colorado (RM 150) and extended to the
confluence of the White and Green river (RM 0).
Due to the project's limited manpower, a knowledge of young squaw-
fish behavior, based on 1979 and 1980 field work in the Green and informa-
tion from others was applied in developing the 1981 sampling program for
the White River. In 1981, sampling was designed for compatibility with
work in progress by the Colorado Division of Wildlife. In July larval
fish (0-30 mm) collections were made, while collections for the larger
(30-70 mm) young Colorado squawfish were made in September. The larval
collections were made as follows:
1. At the top of each stratum, the investigators proceeded down-
stream 5 mi (8 km) and initiated sampling at that location.
All required habitats were sampled with a larval seine (about
0.2cm mesh) in the first 0.5 mi (0.8 km). If all habitats were
not available in the initial 0.5 mi (0.8 km) reach, such lack-
ing habitats were searched for and sampled in the remaining 4.5
mi (7.2 km) of the section. Records were kept of effort and
depth, velocity and substrate of each sample.
2. In addition to the quantitative collections outlined above,
qualitative samples were also taken using a larval dip net.
The investigators actively searched out larvae (any habitat)
at the site of the seine collections. A sample of these larvae
was taken with a.dip net. In addition, other samples were
taken and accurate records were kept for each collection.
3. Workers then proceeded to the beginning of the next 5 mi
(8.0 km) section and repeated the process.
Samples were collected over three habitats: backwaters, eddies and
shorelines. The number of samples collected per habitat is given
below:
1. Backwater (4 collections)
a. deep (2)
b. shallow (2)
13.