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<br />implemented, or if further work is needed before
<br />the operation of the dam would be changed.
<br />
<br />The appropriation, or acquisition of water,
<br />rights is needed to provide instream flows for
<br />recovery, and to offset impacts associated with
<br />continuing water development. The first three
<br />areas that have been targeted for appropriating
<br />water include the Yampa River, a IS-mile reach
<br />of the Upper Colorado River, and the White
<br />River. Flow recommendations that would
<br />presumably prOVide for endangered fishes in the
<br />Yampa and upper Colorado River were presented by
<br />Tyus and Karp(1989) and Kaeding and Osmundson
<br />(1989). These recommendations are being
<br />evaluated.
<br />
<br />Habitat Development and Maintenance
<br />
<br />Development and maintenance of new
<br />habitats, and provision of access to new areas
<br />are considered a priority recovery goal by USFWS
<br />(1987). One category includes the application
<br />of experimental techniques to existing areas to
<br />determine if artificially created habitats will
<br />be acceptable for use. This includes
<br />construction of artificial spawning channels, or
<br />conversion of existing (but not currently
<br />suitable) stream areas to spawning habitats,
<br />construction of nursery habitats, and others.
<br />Another category (e.g., construction of fish
<br />passageways) would include opening up new areas,
<br />or restoring access to other areas that may be
<br />blocked by dams, diversions, etc.
<br />The Green River supports at least two
<br />spawning aggregations of razorback suckers. Ripe
<br />fish are routinely collected, but as elsewhere,
<br />young ,and juveniles are not captured, this
<br />suggests that recruitment, if it occurs at all,
<br />is too low to support the adult populations'
<br />(Lanigan and Tyus 1989, Marsh and Minckley
<br />1989). Hypotheses for the lack of observed
<br />recruitment includes predation of introduced
<br />fishes on the eggs, fry, and young razorback
<br />sucker (Marsh and Langhorst 1988) and the
<br />loss of flooded nursery habitat (Tyus and Karp
<br />1989). Studies evaluating both of these problems
<br />are underway in the Green River, and
<br />recommendations have been made for annual
<br />inundation of seasonallY-flooded lands that are
<br />used by the fish (Tyus and Karp 1991).
<br />
<br />Colorado squawfish migrations have been
<br />observed for a hundred years, and travels of
<br />hundreds of kil ometers have been recently
<br />documented (Tyus 1990). Constructions of dams in
<br />the upper Colorado River basin, including
<br />Flaming Gorge Dam on the upper Green River and
<br />Taylor Draw Dam on the White River, have blocked
<br />passage of migrating Colorado squawfish, as
<br />evidenced by their congregations below these
<br />obstructions prior to spawning season (McDonald
<br />and Dotson 1960, Seethaler 1978, Martinez et al.
<br />1987). However, no passage facility has ever
<br />been tested or built for Colorado squawfish, and
<br />these dams have not been fitted with fish
<br />passageways. Loss of the fish below barrier
<br />
<br />--,
<br />
<br />i
<br />{ ~
<br />
<br />dams, increased fishing pressure thus created,
<br />or attrition has, sooner or later, disrupted
<br />Colorado squawfish migrations.
<br />
<br />'lthOU:~r:~h~::':~~h~~~.f~~O~~~~l~?~~"i:'~~ . ;~
<br />
<br />very early stage of research and development.
<br />Construction of passageways would perhaps best.
<br />be accomplished in areas supporting active
<br />Colorado squawfish migrations, however, such
<br />construction is unlikely because of federal
<br />agency enforcement of prOVisions of the
<br />Endangered Species Act. If passage is tested in
<br />locations where there are no fish migrations or
<br />fish to use them, then new migrations would have
<br />to be established. Passageways must also have
<br />the capability to pass not only adults, but
<br />younger life stages as well, and in both
<br />directions. Retrofitting existing facilities
<br />would be very costly, with no guarantee of
<br />success at this time.
<br />
<br />
<br />Provision of new, or improvement of
<br />eXisting habitats, can only be successful if
<br />ecological requirements of the fishes are met.
<br />This challenge is recognized in the Recovery
<br />Program, and it is stipulated that:(I) Testing
<br />and implementation of management techniques will
<br />not be conducted or potentially affect confirmed
<br />spawning and nursery areas; and (2) The genetic
<br />integrity of wild populations must be protected
<br />when using hatchery-reared experimental animals
<br />(USFWS 1987). There are obviously other
<br />stipulations that could be added, including a
<br />need to develop adequate follow-up, and'provide'
<br />for maintenance of habitats developed. Also,
<br />delineation and protection of sensitive areas
<br />for all species must be a major priority.
<br />
<br />Stocking of Rare Fish Species
<br />
<br />In the past, fish culture was directed at
<br />supporting or restoring sport fishing~ not
<br />restoration of endangered fishes. Thus, there
<br />are many research needs that remain to be
<br />answered regarding the use of hatcheries and
<br />stocking programs in management of endangered
<br />fishes. Without habitat maintenance or
<br />improvement, hatcheries provide temporary
<br />refuges for genetic material and research
<br />facilities for laboratory studies. Fish stocking
<br />programs can benefit management for recovery,
<br />but only in coordination with a comprehensive
<br />program in which life requirements of target
<br />species are well understood, and these
<br />requirements provided. If habitats have not
<br />improved, reintroducti~n of fishes into them
<br />should be considered only a stop-gap measure
<br />(Rinne et al. 1986).
<br />
<br />Stocking of Colorado squawfish for
<br />recovery has not been 'attempted for the Green
<br />River basin because of the naturally reproducing
<br />population there. Re-introduction of Colorado .'
<br />squawfish into areas of the lower Colorado River
<br />basin from which they have been extirpated, was
<br />
<br />178
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