Biological Opinions - Bureau of Reclamation

12 SONCC COHO SALMON ESU
NMFS has determined that the proposed action may adversely affect the SONCC coho salmon
ESU. Therefore, this BiOp analyzes the effects of the proposed action on the SONCC coho
salmon ESU using the following analytical approach.
12.1 Analytical Approach
Pursuant to section 7(a)(2) of the ESA, Federal agencies are directed to ensure that any action
they authorize, fund, or carry out is not likely to jeopardize the continued existence of any listed
species. The implementing regulations for section 7 of the ESA (50 CFR. 402.02) define
“jeopardize the continued existence of” to mean “to engage in an action that reasonably would be
expected, directly or indirectly, to reduce appreciably the likelihood of both the survival and
recovery of a listed species in the wild by reducing the reproduction, numbers, or distribution of
that species.” In addition to the concept of the natural flow regime, the flow and rearing habitat
analyses, the evidence available for consultation, and the critical assumptions discussed in the
SONCC Coho Salmon Critical Habitat section (i.e., section 11.1.5), NMFS uses the following
assessment framework for the SONCC coho salmon ESU.
12.1.1 Overview of NMFS’ Assessment Framework
NMFS uses a series of sequential analyses to assess the effects of federal actions on endangered
and threatened species and designated critical habitat. The first analysis identifies those
physical, chemical, or biotic aspects of the proposed action that are likely to have individual,
interactive, or cumulative direct and indirect effect on the environment (NMFS uses the term
“potential stressors” for these aspects of an action). As part of this step, NMFS identifies the
spatial extent of any potential stressors and recognizes that the spatial extent of those stressors
may change with time (the spatial extent of these stressors is the “action area” for a consultation)
within the action area.
The second step of the analyses starts by determining whether a listed species is likely to occur
in the same space and at the same time as these potential stressors. If NMFS concludes that such
co-occurrence is likely, NMFS then estimates the nature of that co-occurrence (these represent
the exposure analyses). In this step of the analyses, NMFS identifies the number and age (or life
stage) of the individuals that are likely to be exposed to an action’s effects and the populations or
subpopulations those individuals represent.
Once NMFS identifies which listed species and its life stage(s) are likely to be exposed to
potential stressors associated with an action and the nature of that exposure, NMFS determines
whether and how those listed species and life stage(s) are likely to respond given their exposure
(these represent the response analyses). The final steps of NMFS’ analyses are establishing the
risks those responses pose to listed species and their life stages.
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