Lower Columbia River White Sturgeon Population Status Update Oregon Fish and Wildlife Commission 12 February 2016 Exhibit E Tucker Jones Ocean Salmon and Columbia River Program Manager
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Lower Columbia River White Sturgeon Population Status Update
Oregon Fish and Wildlife Commission12 February 2016
Exhibit E
Tucker JonesOcean Salmon and Columbia River Program Manager
Today’s Topics
Overview of long-term population metrics 2015 stock assessment results and current
population status Status of lower Columbia River white sturgeon
fisheries
2
Metrics and Indicators
3
Size Class (inches FL)
Juveniles (21” – 38”) 347,000
Legal (38” – 54”) 144,000
Over-legals (54” – 65”) 9,200
Adults (+65”) 3,000
Total (+21”) >500,000
LCR white sturgeon abundance
4
5
Lower Columbia River Status
LCR 2015Fork Length38"
32"
27"
22"
43"
49"
54"
59"
65"
70"
76"
Fork Length (cm)60 80 100 120 140 160 180 200
0
10000
20000
30000
40000
50000
Legal Population
N= 143,887
Estim
ated
Abu
ndan
ce
White sturgeon legal abundance
6
0
50
100
150
200
250
Fisheries Dependent Estimate
Fisheries Independent Estimate
Projection
Abun
danc
e (in th
ousand
s)
LCR white sturgeon abundance
7
0
1
23
4
56
78
9
10
2011 2012 2013 2014 2015
No. of F
ish (Tho
usan
ds)
Adult Abundance (>65” FL)
LCR white sturgeon productivity
8
0
1
2
3
4
5
620
05
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
Cat
ch P
er N
et
Year
NS
LCR length frequency distribution
9
0.0%
1.0%
2.0%
3.0%
4.0%
5.0%
6.0%54 64 74 84 94 10
3
113
123
133
142
152
162
172
182
192
202
212
222
232
Cat
ch F
requ
ency
(%)
Fork Length (inches)
2015
21 25 29 33 37 9141 44 48 52 6056 64 68 72 76 80 83 87
69%
LCR length frequency distribution
10
0.0%1.0%2.0%3.0%4.0%5.0%6.0% 20122012
0.0%1.0%2.0%3.0%4.0%5.0%6.0%
2013
Legal Slot
Fork length (cm)
0.0%1.0%2.0%3.0%4.0%5.0%6.0%
2014
0.0%1.0%2.0%3.0%4.0%5.0%6.0%
54 64 74 84 94 103 113 123 133 142 152 162 172 182 192 202 212 222 232
2015
Relative freq
uency (%
)
21 25 29 33 37 9141 44 48 52 6056 64 68 72 76 80 83 87
Fork length (inches)
Sea lion predation
What is the current pinniped population status?
11
Sea lion predation – Bonneville Dam
Sea Lion presence grew and by 2005 a hazing program was initiated With the arrival that year of the larger Steller Sea Lion, sturgeon
were being deliberately targeted
12
Sea lion predation – Bonneville Dam
13
Average Cumulative Consumption
Metric N Interpretation Brief Summary
Legal Abundance
143,890 Legal-sized white sturgeon abundance continues to increase and is similar to modeled projections.
Adult Abundance
3,040 Adult abundance metric is below Oregon Conservation Plan conservation status threshold (3-year average of 3,900 adults).
RecruitmentIndex
0.06 CPN 2015 white sturgeon young-of-year recruitment is low. Continues recent trend.
Length FrequencyDistribution
69% Juveniles
Reduced relative abundance of juvenile and sub-legal sized fish over time indicates productivity issues.
Sea Lion Abundance
UP Continued increases in sea lion abundance in the LCR are problematic for white sturgeon population growth
Status Summary
14
Washington Actions
At Commission request WDFW gave status update w/framework for potential modest estuary fishery
Washington did not adopt harvest fishery, did not change current catch and release regulations, requests staff to discuss eliminating catch and release with Oregon.
ODFW staff does not recommend a harvest fishery or eliminating catch and release fisheries
15
Fisheries Response
16
YearTotal May ‐ July Estuary
N Trips % Change N Trips % Change
2013 33,094 16,5692014 3,120 ‐91% 1,620 ‐90%2015 3,004 ‐91% 954 ‐94%
Conclusions & Recommendations
Status of lower Columbia River white sturgeon, while not where we’d like it, is not in danger. Still more than 500,000 fish Adult population has been stable over the
last five years and not projected to decline Legal abundance is >140,000 and with no
retention we are escaping more every year Sturgeon life history strategy guards against
short periods of low productivity We are monitoring the population closely
Not recommending any changes to fisheries structure at this time 17
END
Questions/Discussion?
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