8097

• UCREFRP Catalog Number: 8097
• Author: American Fisheries Society.
• Title: Proceedings of the 18th Annual Meeting, Colorado - Wyoming Chapter, American Fisheries Society.
• USFW Year: 1983.
• USFW - Doc Type: March 2-3, 1983.
• Copyright Material: NO

Several loads of 4-inch to S-inch trunk diameter aspen trees were deli-
vered to the release sites to coincide with the release of the relocated
beaver. This was done in the hopes that the beaver would begin to build new
dams or repair old ones with these larger, more stable materials. Progress
was slow and somewhat disappointing the first year with only three beaver
being reloacted, but after the release of four additional beaver in June
of 1982, dam building abruptly began and continued until winter freeze-up
in late November and early December of 1982. The beaver made complete use
of the supplied aspen in the construction of their dams. Three major beaver
dam complexes have been built within the exclosure, raising the water table
behind the dams from one to three feet. Stream flows at these sites are now
being dissipated laterally across the dams and into relatively large subirri-
gated meadow areas rather than vertically into a box-shaped, gully-cut chan-
nel (Smith 1983).
By the end of the second year, full riparian recovery was underway in
those areas with elevated water tables resulting from beaver activity.
Willow regrowth and resprouting averaged five feet in height in two years of
rest. In downstream areas within the exclosure, where very limited willow
root stock was present, where beaver activity was absent, and where the
water table fluctuates throughout the year, willow recovery was negligible.
While willow recovery may eventually result from rest alone, the added in-
fluence of an elevated, stable, water table, resulting from beaver activity,
may be a key to accelerated riparian habitat recovery. Additionally, golden
willow, plains cottonwood, and Russian olive bare root trees were planted
in April of 1982 along the downstream portion of the exclosure in an attempt
to establish some tree-type vegetation in this area. Because of the lack of
beaver dam-building activity in this area, and because of the seasonal water
table fluctuations, these trees may have a more difficult time surviving.
This will be monitored as the study continues.
Riparian habitat recovery at Sage Creek occurred in spite of winterlong
livestock grazing use. This second study area is unfenced and has tradition-
ally been totally available for livestock use. Sage Creek is a deep,
gully-cut stream which presents many obstacles to gully stabilization
efforts. In years past, beaver have attempted to colonize Sage Creek, but
failed because their dams have consistently been washed out by high spring
flows. No beaver were relocated to this area as a part of the study pro-
ject, but by early fall 1981, beaver activity was noted. The animals were
attempting to reestablish themselves within the study area. In order for
their dams to successfully withstand high spring flows, we felt that struc-
tural reinforcement was needed. Therefore, in an effort to dispel the mis-
conception that we were simply "feeding" aspen trees to these animals in
the project areas, and to still provide structural stability to the dams,
we have applied the same basic principles of the aspen structural stabili-
zation concept in an entirely different manner. Rather than provide aspen,
as was done on Currant Creek, truck tires were wired together and staked
across small blowout-prone beaver dams. The beaver have built these dams up
to two feet higher than was possi~le ~efore, impounding three to four times
more water. These dams have subsequently withstood the normal runoff events
in 1982, and have formed major mud terraces. One particularly large dam,

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