Biological Opinions - Bureau of Reclamation

much as 40 to 60 percent, suggesting a lack of resiliency. SNSs in UKL are also vulnerable
because most are well past their average life expectancy, and LRSs are at their average life
expectancy, thus the rate of decline could increase if there is not substantial recruitment into the
adult age class. However, recruitment of both species into the adult population in UKL in the
past decade has been nearly nonexistent, and there is no evidence of large cohorts of young
suckers that could enter the adult population in the next few years. Loss of the UKL populations
would leave only one self-sustaining population of the LRS and two populations of the SNS;
thus, there is little redundancy for either species, adding to their risk of extinction. Given this
information, the Service finds that LRS and SNS populations, especially the SNS population in
UKL, are at a high risk of extinction.
7.6 Survival and Recovery Needs of the LRS and the SNS
The 2013 revised recovery plan for the LRS and SNS (USFWS 2013) describes their survival
and recovery needs, which are:
Adequate quality and quantity of habitat to support the needs of all life stages of LRS and
SNS.
o Improved water quality to a level where adverse effects are not sufficient to
threaten the continued persistence of the LRS and the SNS.
o Connectivity throughout the range of LRS and SNS to ensure appropriate genetic
exchange among populations, to provide access to spawning and refugial areas,
and to permit return of downstream migrants.
A sufficient number of viable, self-sustaining populations of the LRS and SNS to buffer
against localized extirpations.
o Substantially reduced entrainment of larval, juvenile and adult LRS and SNS
particularly in UKL.
o Increased frequency and magnitude of recruitment into the adult spawning
populations of both the LRS and the SNS.
o Populations of sufficient sizes to ensure genetic variability to enable LRS and
SNS to respond to changing ecosystem conditions.
7.7 Reclamation’s Klamath Project
7.7.1 Hydrologic Alteration
The Reclamation Act of 1902 (43 U.S.C. 391 et seq.) authorized the Secretary of the Interior to
locate, construct, operate, and maintain works for the storage, diversion, and development of
water for the reclamation of arid and semiarid lands in the western States. Congress facilitated
development of the Klamath Project by authorizing the Secretary to raise or lower the level of
Lower Klamath and Tule Lakes and to dispose of the land uncovered by such operation for use
under the Reclamation Act of 1902. The Oregon and California legislatures passed legislation
for certain aspects of the Klamath Project, and the Secretary of the Interior authorized
construction May 15, 1905, in accordance with the Reclamation Act of 1902 (Act of February 9,
61