1. Tracking steelhead migration from the Columbia River through the Pacific Ocean: a proposal
Michelle Rub and Laurie Weitkamp
NOAA Fisheries
Northwest Fisheries Science Center

2. The salmon life cycle Major questions
Where do they go (migratory route)?
What habitats do they use (temp, depth, prey)?
Are there survival bottlenecks?

3. Ocean distribution of North American steelhead (1956-2000)
“few and far between”
Which way do they go?
Gritsenko 2002

4. Why we need to know more about Columbia steelhead ocean residence
Better understand how if or how ocean conditions influence growth and survival
Where and when does it happen?
Determine what “good” ocean conditions are for steelhead
Predict how they might fare with climate change
Changing productivity of California current
Explosion of Humboldt squid

5. Study Objectives
Determine feasibility of tagging Columbia River steelhead in estuary
Test three acoustic ‘detection systems’ in the North Pacific
Supplement ‘sporadic’ but precise information on geo-position with continuous information on temperature and depth
►Increase our understanding of ocean residence period for Columbia steelhead

6. Talk outline Collecting Columbia steelhead Tagging technology
Existing sampling in Columbia estuary
Tagging technology
Acoustic, archival
Listening arrays
Coastal, oceanic, living
Expected results

7. Collecting juvenile Columbia River steelhead
Existing NWFSC sampling for out-migrating yearling smolts
Sampling at edges of deep channels
Every other week, mid April to late June
2007-present: caught over 200 steelhead/yr
CWT & PIT tags = fish from throughout basin
The reason we tow the net is to catch more juvenile salmon. By towing upriver (in the spring) or downriver (in Sep) we can get a lot more salmon, particularly when salmon abundance is low (and we’d be out all week trying to get our 50 individuals of each spp/age class). It’s not quantitative, however (because the area swept is difficult to determine giving variable towing speed distance & between boats), so they’re excluded from abundance estimates.

8. Sampling equipment: purse seine
Minimizes injury and descaling to fish
Post-release survival expected to be high
Allows sampling in deep water (far from beach)
Net dimensions: 500 x 35 ft

9. Pulling it on deck
Setting the net
Fish in the bunt
Pursed net

10. Sorting, counting and measuring fish

11. Steelhead timing in the Columbia River estuary

12. Steelhead size, (n = 679)
Mean size mm FL (range )

13. minimum fish weight to maintain 2% maximum
Acoustic Transmitters
69 kHz
nominal pri interval = 180 sec
(range = sec)
VEMCO
21mm V7 V9
model
power output in
dB re
tag life
diameter
weight in air
minimum fish weight to maintain 2% maximum
tag: body
V7/2L
136
230d
7mm
1.6g
80g
V7/4L
337d
1.8g
90g
V9/6L
142
275d
9mm
2.9g
145g
Goal is to maximize tag life and power output while keeping the weight of the tag to a minimum.

14. Advantages of acoustic transmitters for this study
can be used to collect precise geo-positional information
information transferred to receiver for collection
Disadvantages of acoustic transmitters
long-lived tags are large/heavy
expensive (~$275 each)
must be ‘heard’

15. SWFSC towed hydrophone array The POST project acoustic receiver arrays
In 2010, there will be three different types of ‘receivers’ operating in the Northern Pacific Ocean with the capability of hearing or detecting VEMCO acoustic tags.
SWFSC towed hydrophone array
The POST project acoustic receiver arrays
SWFSC elephant seal array
*Extensive collection of acoustic receivers in the lower Columbia River and estuary

16. SWFSC towed hydrophone acoustic surveys from 2008
Red =Aug & Sept
Green = Oct & Nov

17. Detection range:
V9 tags ~ m
V7 tags ~ m
Positions of VEMCO VR2 and VR3 acoustic receiver lines maintained by the Pacific Ocean Shelf Tracking Project (

18. Photo courtesy of Sean Hayes SWFSC
Juvenile elephant seal with a BCT, and an archival tag attached to the animal’s back, and a satellite tag attached to the animal’s head.

19. Elephant Seal Acoustic Array
Image from TOPP- Simmons & Costa

20. record temperature and depth
Archival Tags
record temperature and depth
pre-programmed sampling interval from 1/10 sec to 32hrs
Capacity = 32,000 records
model
records
tag life
dimensions
weight in air
minimum fish weight
Wee Tag Slim
temperature and depth
18x12x6.75 mm
1.7g
85g
Wee Tag Light
temperature
~11mm dameter, 6.25mm height
1.1g
55g

21. Advantages of archival tags
long-lived tag smaller than AT tag
less expensive (~$ each)
large storage capacity
collects a continuous record of temperature and or pressure
Disadvantages of archival tags
no precise information on geo-position
must be physically retrieved

22. Retrieving Archival Tags
stocks originating above Bonneville Dam can potentially be collected in the separation-by-code system
lower river stocks could be collected upon return to the hatchery of origin, from a trap or concrete collection facility
SARs range from ~1-3% for SR steelhead depending on the migration year and origin

23. Archival tags: 80% >189 mm
Steelhead size, (n = 679)
Minimum steelhead size by tag
Archival tags: 80% >189 mm
V7-2L tags: 50% >214 mm
V7-3L: 40% >222 mm
V9: 7% >259 mm
Mean size mm FL (range )

24. Cost Acoustic Tags ~$275 each x 100 = $27,500
Archival Tags ~$90 each x 150 = $13,500
Misc. ~$3,500
Total = $44,500

25. Expected results
Determine feasibility of tagging Columbia River steelhead in estuary
Acoustically-tagged steelhead will be “heard” somewhere in the North Pacific
Archival-tagged steelhead will return with temperature record of ocean migration
►Increase our understanding of ocean residence/migration patterns for Columbia steelhead