7152

• UCREFRP Catalog Number: 7152
• Author: Holden, P. B.
• Title: Relationship between Flows in the Yampa River and Success of Rare Fish Populations in the Green River System.
• USFW Year: 1980.
• USFW - Doc Type: Logan, Utah.
• Copyright Material: NO

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Table 2. Numbers of Colorado squawfish caught by Vanicek (1967) in the
Green River, 1964-1966 in Dinosaur ~ational Monument by year
class.

Year of Sampling Year classes
capture effort 1962 1963 1964 1965 1966
1964 High 1 357 275
1965 High 4 29 53 42
1966 High 0 5 8 1 560
--------------------------------------------
Tota 1 5 391 336 43 560
Reproductive Success Good Good Good Poor Good

actually have been Age II fish. A recent conversation with Dr. Vanicek

These data suggest that some of the Age I fish caught in 1964 may

indicated this was very possible. If this were so, the 1962 year class

would not appear to be as small as indicated in Table 2. Therefore, it

is concluded that 1962 was a good year for squawfish reproduction in
Dinosaur National Monument because the available data suggests 1962 was
a better year than was initially indicated by Vanicek (1967).

There is no data to suggest that 1965 was also a good year, for
an analysis of Vanicek's data sheets indicates that effort in 1965 was

similar to the other years of his study.
Most of the young squawfish collected by Vanicek (1967) were taken
in Echo Park, although young squawfish were also taken in Island Park
and Split Mountain. No young squawfish were taken in the Green River