Tracking steelhead migration from the Columbia River through
the Pacific Ocean: a proposal
Michelle Rub and Laurie WeitkampNOAA Fisheries
Northwest Fisheries Science Center
The salmon life cycle
Major questions Where do they go
(migratory route)? What habitats do they
use (temp, depth, prey)?
Are there survival bottlenecks?
Ocean distribution of North American steelhead (1956-2000)
Gritsenko 2002
Which way do they go?
“few and far between”
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
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
Talk outline• Collecting Columbia steelhead
– Existing sampling in Columbia estuary• Tagging technology
– Acoustic, archival• Listening arrays
– Coastal, oceanic, living• Expected results
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
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
Setting the net
Pursed net
Pulling it on deck
Fish in the bunt
Sorting, counting and measuring fish
Steelhead timing in the Columbia River estuary
Steelhead
0.0
2.0
4.0
6.07-
Apr
17-A
pr
27-A
pr
7-M
ay
17-M
ay
27-M
ay
6-Ju
n
16-J
un
26-J
un
6-Ju
l
Date
No/
roun
d ha
ul
2007
2008
2009
Steelhead size, 2007-2009 (n = 679)
0
20
40
60
80
100
12013
0
150
170
190
210
230
250
270
290
310
Fork length (mm)
Freq
uenc
y
Mean size 214.9 mm FL (range 132-320)
Acoustic Transmitters• 69 kHz• nominal pri interval = 180 sec(range = 90-270 sec)
21mm
V9V7
VEMCO
model
power output in
dB re 1µPa @1m 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 136 337d 7mm 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.
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’
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
Red =Aug & Sept
Green = Oct & Nov
SWFSC towed hydrophone acoustic surveys from 2008
Positions of VEMCO VR2 and VR3 acoustic receiver lines maintained by the Pacific Ocean Shelf Tracking Project (http://www.postcoml.org/)
Detection range:V9 tags ~400-500mV7 tags ~ 200-300m
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.
Photo courtesy of Sean Hayes SWFSC
Elephant Seal Acoustic Array
Image from TOPP- Simmons & Costa
Archival Tags• record temperature and depth• pre-programmed sampling interval from 1/10 sec to 32hrs• Capacity = 32,000 records
model recordstag 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
Advantages of archival tags• long-lived tag smaller than AT tag• less expensive (~$90-125 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
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
Steelhead size, 2007-2009 (n = 679)
0
20
40
60
80
100
12013
0
150
170
190
210
230
250
270
290
310
Fork length (mm)
Freq
uenc
y
Archival tags: 80% >189 mm
V7-2L tags: 50% >214 mm
V7-3L: 40% >222 mm
V9: 7% >259 mm
Minimum steelhead size by tag
Mean size 214.9 mm FL (range 132-320)
Cost• Acoustic Tags ~$275 each x 100 =
$27,500• Archival Tags ~$90 each x 150 = $13,500• Misc. ~$3,500Total = $44,500
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
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