The Status of Puget Sound Chinook Salmon
What do we know? and How do we know it?
Kit RawsonTulalip 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
Snoqualmie Chinook
0
500
1000
1500
2000
2500
1975 1979 1983 1987 1991 1995 1999
NOR Escapement
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
Snoqualmie Chinook
0
500
1000
1500
2000
2500
3000
1975 1979 1983 1987 1991 1995 1999
NOR Esc Total Esc
Adult Return Run Reconstruction
Escapement + Terminal harvest + Mixed-stock harvest
Chinook complications Immature fish harvest Non-landed mortality Age distribution
Coded-Wire Tag Program
Who Catches These Fish?Snohomish Chinook – 1980-1986
Term NetPS Sport
PS PreTrm Net
Canada
Alaska
Escapement
WA ocean
W ho Catches These Fish?Snohom ish Chinook – 2000 Plan
WA ocean
Escapement
CanadaPS PreTrm
Net
PS Sport
Term Net
Snoqualmie Chinook
0
5000
10000
15000
20000
25000
1975 1979 1983 1987 1991 1995 1999
W(t) W(t)+C(t)
Puget Sound ChinookMarine Survival Index
Marine Survival IndexPuget Sound Fall Fingerling
0
1
2
3
4
5
6
7
8
9
1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993
Brood Year
Ind
ex
(1
98
6-1
99
2 B
as
e)
STFF
NIFF
NKFF
GCFF
GRFF
GAD
Mean
Snoqualmie – Current Conditions
0
1000
2000
3000
4000
5000
0 1000 2000 3000 4000 5000
Spawners
Rec
ruit
s
Equilibrium = 2,300
Snoqualmie
0
10000
20000
30000
0 10000 20000 30000 40000
Spawners
Rec
ruit
s
Equilibrium = 19,300(low mar. surv.)
HISTORIC
RECOVERY GOAL
RECENT OBSERVATIONS
Juvenile Outmigration
Juvenile outmigration Sampling error ( 0.75 – 1.65%
captured) Traps upstream of
some rearing areas Variable time and
size of migration
Sakgit 0+ ChinookBrood PED wild
Year Est. Esc. (million) outmigrants surv cfs date1989 8084 20.01 1.7 8.5% 88200 05-Dec1990 18303 45.30 0.5 1.1% 142000 25-Nov1991 7060 17.47 2.4 13.7% 40100 01-Feb1992 8334 20.63 3 14.5% 27600 26-Jan1993 6584 16.30 2.7 16.6% 32100 11-Dec1994 6019 14.90 1.5 10.1% 55700 28-Dec1995 7732 19.14 0.7 3.7% 132000 30-Nov1996 11664 28.87 4.5 15.6% 47600 20-Jan1997 5913 14.63 2.4 16.4% 32800 17-Dec1998 15695 38.85 6.4 16.5% 51900 14-Dec1999 5395 13.35 1.7 12.7% 76000 13-Nov
high flow
Skagit 0+ Chinook
0%
5%
10%
15%
20%
0 50,000 100,000 150,000
Skagit 0+ Chinook
0%
5%
10%
15%
20%
0 50,000 100,000 150,000
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 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