The Status of Puget Sound Chinook Salmon What do we know? and How do we know it? Kit Rawson Tulalip Tribes

Salmon Recovery What was the status of the resource historically? What is the status of the resource now? What is the desired future status of the resource? How’d we get here? Recovery Plan

Salmon Recovery What was the status of the resource historically? What is the status of the resource now? What is the desired future status of the resource? How’d we get here? Recovery Plan

Population Parameters (from “VSP”) Abundance Productivity Diversity Spatial Structure

Abundance Census of individuals (how many?) Total biomass (how much?) Count or biomass at: single life stage whole population

Abundance Census of individuals (how many?) Spawning escapement Eggs Juvenile outmigration Adult return

Spawning Escapement

Smith and Castle (1994) Redd counts (approx. weekly) Aerial, foot, float surveys Assume 2.5 fish/redd, 21-day “visible redd life” Supplemented with peak live, dead counts Varying methods for expanding to unsurveyed or poor visibility areas

Spawning Escapement No estimate of variance No standard method for separating hatchery and natural-origin

Adult Return Run Reconstruction Escapement + Terminal harvest + Mixed-stock harvest Chinook complications Immature fish harvest Non-landed mortality Age distribution

Coded-Wire Tag Program

Puget Sound Chinook Marine Survival Index

Snoqualmie – Current Conditions Equilibrium = 2,300

Snoqualmie

Juvenile Outmigration

Juvenile outmigration Sampling error ( 0.75 – 1.65% captured) Traps upstream of some rearing areas Variable time and size of migration

Puget Sound TRT A&P Workbooks For each of 22 natural chinook populations

Puget Sound TRT A&P Workbooks Data (some incomplete) Natural escapement estimates Hatchery/natural origin split Exploitation rate estimates Juvenile production Environmental predictors (marine survival, flow)

Puget Sound TRT A&P Workbooks Analyses Run reconstruction Trends and variance about trends Spawner/recruit relationships

Questions Q: What are the best indices of salmon status to use across species and areas? A: Focus on natural populations/stocks Look at trends in natural escapement and total return Control for marine survival and other signals

Questions Q: Over what time period should we assess recovery? Can we separate factors affecting abundance on different time scales? Should we? A: 20 years + Yes

Questions Q: How accurately do we need to measure salmon populations to effectively manage them? A: Management systems need to be robust to imprecise and inaccurate assessments of status Even so, we probably need better estimates than we have now.

Questions Q: Regional or “top-down” approach best (both within and between ESUs)? A: Regional/local focus is best for adaptive management Needs a few, well-understood guiding principles