7798

• UCREFRP Catalog Number: 7798
• Author: Richardson, S.
• Title: Conceptual Management Plan for Razorback Sucker Habitat Enhancement in Flooded Bottomlands, Escalante Ranch, Jensen, Utah.
• USFW Year: 1994.
• USFW - Doc Type: \
• Copyright Material: NO

I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I

Larval razorback suckers utilize a variety of invertebrates as a
primary food source. The production of the invertebrate
community may be directly related to the growth and survival of
larval razorback suckers at this site. Invertebrate production
within the main channel of the Green River and its backwaters is
extremely limited. However, invertebrate production of both
water column and benthic species appears to be high in the
wetland area of this site. The most important groups of
invertebrates occurring on the site include chironomids,
cladocera and copepoda. Invertebrate production appears to reach
its peak in July and August (Cooper and Severn 1994b).
Therefore, it would be important that young razorback suckers
have access to the wetlands during these months. A complete
summary of benthic and water column invertebrates sampled at this
site can be found in Cooper and Severn (1994b, See Appendix 2).

Land Manaqement

The wetland portion of the Escalante Ranch has been inhabited
since the late 1800's. The Green River was diked at that time,
preventing most natural flooding of the area and use by native
fishes. Two homes, a barn and a hay rack were constructed on the
site. The presence of these structures indicate that relatively
little flooding occurred. The standing water that currently is
found on the site was absent. Most likely, the inhabitants cut
native hay from the meadows that existed in the area now occupied
by wetlands.

Aerial photographs taken in 1937 indicate that standing water was
still absent from the area that is now a wetland. The site
appears to have been used for grazing and pasture land during
this time period. Cottonwood trees were an important component
of the vegetation on the site.

Sometime between 1937 and 1952, flood irrigation of the terrace
lands was implemented. Standing water is apparent on the site.
The commencement of irrigation appears to have been responsible
for the hydrologic regime that currently exists in the wetland
area.

Aerial photographs taken in 1961, a low runoff year, show water
levels in the wetlands which are comparable to current levels.
Thus, flooding of the wetlands does not appear to be completely
dependent on the Green River. Flood irrigation was practiced
during this period with an increase of acreage under irrigation.
Acreage under irrigation increased even more dramatically by
1969.

Center pivot irrigation
between 1976 and 1979.
appears to have reduced
southern portion of the

sprinklers were first put
This change in irrigation
flows or dried up springs
site. Vegetation changes

into use
practice
locat~d in the
include the

17