WSP03164

• Author: USFWS
• Title: Management Plan for Endangered Fishes in the Yampa River Basin - Volume II -Appendices - USFWS - 09-01-2004

002655

provided a substitute food supply. Significant future reductions in game fish abundance,
either naturally due to loss of the native fish forage base or through mechanical removal
by Recovery Program control projects, may create a food supply shortage for eagles
during any lag time required for native fish populations to increase. Inasmuch as this
creates yet another complication when setting nonnative control policy, it is valuable
information to take into consideration.

2. Page 120: Discussion of endangered fish: While it appears that the reduction of
peak flows will negatively impact the endangered fish, I think that this section does not
make a compelling argument that increasing the baseflow in the summer will more than
offset the impacts of the reduction of peak flows. The bottom line is that these fish
evolved in the absence of dams, thus are dependent on the natural flow fluctuations in
rivers. The jury still seems to be out on the impacts of non-native fish control on
increasing the numbers of these endangered fish. So to say that non-native fish control
will balance the negative impacts of the reduction of peak flows does not seem to be
supported by the current scientific knowledge. There is an interplay of fish population-
flow relationships and native fish-nonnative fish interactions in available habitat that are
not understood. Implying trade-offs between potential impacts and benefits here is
premature.

Conclusion

Colorado commends the Program for the research which has gone into this
document. We look forward to discussions with Program staff regarding the above-
mentioned issues.

Sincerely,

~(~

Tom Blickensderfer
Endangered Species Program
Director

RECEIVED
SEP 5 2003

Co River Recovery Program

Appendix F - Notice of Availability/Comments

F-5