9681

• UCREFRP Catalog Number: 9681
• Author: Burdick, B.
• Title: Biological Criteria For Use Of Fish Passage In The Recovery Of Threatened and Endangered Fishes in the Upper Colorado River Basin - Draft.
• USFW Year: 1988.
• USFW - Doc Type: \
• Copyright Material: NO

squawfish. However, as mentioned earlier, more movement data are available
for squawfish than for the other three fishes, and squawfish generally have
shown a tendency for long-distance movement related to spawning, more so than
the other fishes studied. It is felt at this time that fish passage would
immediately best benefit the squawfish. Therefore, for these reasons, this
document will consider passage for only sub-adult and adult Colorado
squawfish. The biological merits of using fish passage for the other three
fishes is not within the scope of this document and should be addressed as new
data become available for these fishes.
The purpose of this document is to offer some realistic situations where
fish passage could be used as a non-flow management alternative to offset
impending loss of habitat in some river reaches occupied by Colorado squawfish
in the upper basin. Furthermore, this document will attempt to provide
some general guidelines for recommending when fish passage or other methods
could be used that would biologically benefit squawfish either toward recovery
and/or provide for their continuance in a river reach if a proposed instream
obstruction would separate an existing population. Information developed for
the "Rare and Endangered Colorado River Fishes Sensitive Areas" document
developed by the Upper Colorado River Basin Biological Subcommittee and
contained in the Implementation Plan was used in this report to assist in
determining when and where -Fish passage would be appropriate. It should be
pointed out that this document is currently under review, and will be updated
and refined as new data become available. These recommendations would be
available for use in Section 7 biological opinions where fish passage is a
consideration for mitigation, recovery, or maintenance for Colorado squawfish
in the UCRB.
In any event, each site will have to be judged for the specific merits of
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