Biological Opinions - Bureau of Reclamation

1.2.1.8. Incidental Take Caused by Proposed Conservation Measures
Canal Salvage
Reclamation proposes to capture and relocate suckers found in the irrigation canals at the end of
the irrigation season. Based on recent capture rates, up to 1,500 age-0 suckers could be relocated
annually. Of these, we assume all will be harassed because it is likely to cause substantial
disruption of normal behaviors, and 2 percent (i.e., 30 total LRS and SNS) will be harmed by
unavoidable injuries received during capture and transport.
Relocation of Suckers from Lake Ewauna to UKL
Reclamation proposes to capture and relocate suckers from Lake Ewauna and move them to
UKL. We estimate up to 2,000 total LRS and SNS are likely to be relocated by this effort over
the term of the BiOp, with an annual average of 200 adults over the term of the BiOp. All of
these fish will be harassed because it is likely to cause substantial disruption of normal
behaviors. Of these, we assume 2 percent (i.e., 40 total LRS and SNS over the term of the BiOp)
will be harmed by unavoidable injuries received during capture and transport.
Controlled (Captive) Propagation
Reclamation proposes to fund a USFWS-implemented controlled-propagation program for the
LRS and SNS. The details of the controlled-propagation program have not been fully developed.
When the details become available, the USFWS will either apply for an ESA Section 10
recovery permit for authorization of purposeful take. To implement the propagation program,
we anticipate that up to 30,000 to 40,000 eggs or 50,000 to 75,000 larvae will be removed from
the wild each year. The source of the eggs or larvae will likely be the Williamson River. We
estimate that 10 percent (7,500) of the larvae could die.
Investigation of Flow Reductions at Link River Dam
This proposed conservation measure is not likely to result in take of suckers above that already
considered because it is focused on minimizing take at the dam.
Sucker Recovery Implementation Team Involvement
Reclamation proposes to participate in the LRS and SNS Recovery Implementation Team. No
specific details are available for those activities at this time, so effects to listed species will be
covered with an ESA Section 10 recovery permit when sufficient details are available.
1.2.1.9. Incidental Take Caused by O & M Activities
Reclamation intends to perform various annual maintenance activities that could require sucker
salvage, and this could result in annual harassment and/or harm of up to 10 total of all life stages.
13.2.2 Incidental Take Summary for LRS and SNS
In summary, we anticipate that the proposed action could result in annual take, as harm, of up to
363,565 of all LRS and SNS life stages, and up to 2.04 million of all life stages could be
harassed annually (
Table 13.3). The vast majority of the take as harm (99 percent) will be larvae. Entrainment is
the largest single action resulting in take.
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