8290

• UCREFRP Catalog Number: 8290
• Author: Day, K. S. and C. Crosby.
• Title: An Assessment of Young-of-the-Year Colorado Squawfish ‎(Ptychocheilus lucius)‎ Use of Backwater Habitats in the Green River, Utah.
• USFW Year: 1997.
• USFW - Doc Type: FG-33,
• Copyright Material: NO

describe a situation similar to that reported here. Haines and Tyus (1990) st
Green River backwaters were found most frequently in backwaters deeper than 0.
Colorado squawfish, in addition, used backwaters with surface area greater tha
later reported mean surface area for Colorado squawfish backwaters of 1158 m2,
269 m2 for unused backwaters (Tyus and Haines 1991). This mimics results of t
Colorado squawfish backwaters averaged 992 m2 and unused backwaters had mean s
of 404 m2. There were seasonal variations in the size of backwaters used by C
Backwaters used in the spring were deeper (0.44 m) and had greater surface are
those used in summer (0.31 m; 993 m2) and fall (0.3 m; 918 m2). This differen
of temperature differences between main channel and backwater habitats in the
discussed below) and temperature stability in large, deep backwaters during th
period.
Turbidity has also-been noted as a distinguishing characteristic for Col
use. Reports by Grabowski and Hiebert (1989) and Tyus and Haines (1991) point
Colorado squawfish use in more turbid waters. Although the three-category rat
study prevented numerical analysis of turbidity, contingency table analysis by
showed that Colorado squawfish were not distributed evenly across those three
Backwaters with Colorado squawfish were more likely to have higher turbidity r
unused backwaters.
Temperature and temperature fluctuation have also been implicated in Col
squawfish backwater preference. Tyus and Karp (1991) reported that Colorado s
most abundant in backwaters as warm as, or warmer, than the main channel. The