Our new Biological Assessment is out - Klamath Basin Crisis

Klamath Project Operations Biological Assessment
Coho Salmon: Effects of the Proposed Action on Coho Salmon
Figure 3-27. Map of the Lower Klamath River Basin denoting the 16 model reaches.
These boundaries are similar to those used to segregate the Lower Klamath River Basin
into the upper, middle, and lower Klamath River (see Figure 3-1).
In summary, the life-cycle model simulated the effects of temperature and flow on
individual coho salmon populations and life stages as they migrated through the
Klamath River main stem. Temperature effects were treated in the model through
adult pre-spawning survival, juvenile carrying capacity, growth, and smolt
survival. Flow effects were explicitly treated in the model through juvenile
carrying capacity and smolt survival. The model simulated the effects of
temperature and flow on 50 spawning populations, through 5 life stages, over a
span of 40 weeks for each year. Each model simulation was run for 12 years (3
complete life-cycles) under constant conditions. The model can be extended over
a greater time period to include variable environmental conditions.
VSP Guidance
The format for this section of the BA will provide an analysis of the Proposed
Action’s effects that correspond to each of the four VSP criteria: abundance,
productivity, spatial structure, and diversity. Life-cycle simulations are used to
examine how the Proposed Action will influence the four VSP criteria for the
SONCC coho salmon ESU.
264