Originally Posted By: eyeFISH

Willapa Bay chinook immediately came to mind as WFWC/WDFW has a policy aimed at rebuilding those coastal chinook. Mind you, the habitat is NOT ideal chinook habitat.... but what's there is in hella'better shape than what you I-5er's have in Pugetropolis. For that matter, chinook habitat is hella'better ANYWHERE on the coast than what chinook have in PS.



Applying the sim to WB, where the goal is ultimately 4300 wild spawners.

I set habitat sufficient to carry 5500.
I set marine predation at 40% to reflect pre-terminal harvest (BC/AK interception is actually closer to 50% )
I set the inside ER at 14% which is where the WB Policy eventually expects us to land.

This scenario produces a viable steady state population of spawners of about 1600-1700.

If we could somehow get BC and AK to cut their interceptions down by 1/2 (20%), the sim ramps up to a population of 3500-4000 spawners in just a few generations.

If we improve habitat access/quality to 7500 fish, we ramp that population up to a steady state of about 4500-5000.

The actual numbers might differ from reality, but I believe the interaction between the variables is on solid ground.

...

I did one final exercise to see what level of exploitation restraint it would require to reach a steady state of maximum sustainable abundance.... where the population reaches equilibrium at carrying capacity.

That happens at about 15% exploitation (regardless of who is doing the exploiting).

_________________________
"Let every angler who loves to fish think what it would mean to him to find the fish were gone." (Zane Grey)

"If you don't kill them, they will spawn." (Carcassman)


The Keen Eye MD
Long Live the Kings!