306 
Fishery Bulletin 117(4) 
Table 2 
Locations and dates of releases of juvenile Chinook salmon (Oticorhynchus tshawytscha) tagged with coded wire tags (CWTs) and 
released from hatcheries in the Columbia River Basin in 2012. These CWTs were found in the forestomach of a dead, stranded 
harbor porpoise (Phocoena phocoena ) recovered from the Long Beach Peninsula in southwestern Washington on 22 August 2012. 
Also provided are the runs of the Chinook salmon and the basins where they were released. The code 09blank may or may not be 
associated with Chinook salmon because no data are available. ID=Idaho; WA=Washington; OR=Oregon. Data source: Regional 
Mark Information System (available from website). 
CWT numbers 
Run (return to 
freshwater) 
Basin 
Release date 
range 
100201 
Fall 
Upper Snake River, above Lewiston, ID 
3 May 
220216,220224 
Late fall 
Clearwater River, ID 
8 May-12 June 
220324,220325, 220326, 
Late fall 
Upper Snake River, above Lewiston 
21-23 May 
220327 
220328,220329 
Late fall 
Clearwater River 
21-23 May 
055233, 055260 
Fall 
Wind River, White Salmon River, WA 
13 April 
636417 
Fall 
Lower Snake River, below Clarkston, WA 
29-30 May 
636418 
Fall 
Grande Ronde River, Imnaha River, Asotin Creek, OR and WA 
29-30 May 
055399,055404, 055527, 
Fall 
Wind River, White Salmon River 
11-13 April 
055528 
635273 
Spring 
Cowlitz River, WA 
26 March-2 April 
635776 
Summer 
Wenatchee River, Entiat River, Lake Chelan, WA 
25 April 
055364 
Summer 
Wenatchee River, Entiat River, Lake Chelan 
17 April 
635690 
Summer 
Methow River, Okanogan River, WA 
16 April-7 May 
636370 
Summer 
Columbia River, from Priest Rapids Dam to Grand Coulee, WA 
16-29 May 
090566,090567, 090582, 
Fall 
Youngs Bay, Clatskanie River, OR 
7 May 
090583 
090571 
Fall 
Sandy River, OR 
18 May 
636419 
Fall 
Grande Ronde River, Imnaha River, Asotin Creek 
24 May 
090587 
Late fall 
Upper Snake River, above Lewiston 
22-24 May 
090585,090586 
Fall 
Umatilla River, OR 
23 May 
090526 
Spring 
Willamette River, OR 
15 March 
09blank 
Unknown 
Unknown 
Unknown 
16 June 2012. A third PIT-tagged Chinook salmon (PIT tag 
no. 3D9.1C2DDEE358) also was released on 22 May 2012 
but not as part of the same group as the 2 Chinook salmon 
noted previously. This third fish was detected at 2 other 
locations: the juvenile bypass system of Little Goose Dam 
in southeastern Washington on 4 June 2012 and the juve¬ 
nile bypass system of John Day Dam, at the boundary of 
Oregon and Washington formed by the Columbia River, on 
18 June 2012. The 2 remaining PIT-tagged Chinook salmon 
(PIT tag nos. 3D9.1C2DD706F1 and 3D9.1C2E0A858F) 
were not detected in other systems during their outmigra¬ 
tion to the Pacific Ocean. 
Of the 91 CWTs, 88 tags came from juvenile Chinook 
salmon from hatcheries in the Columbia River Basin 
that were released between 15 March and 12 June 2012 
(Tables 1 and 2). These 88 CWTs represent 32 different tag 
batch numbers from 15 hatcheries located in Idaho, Wash¬ 
ington, and Oregon. The juveniles were from fall (number of 
tagged fish [?;]=81), spring (n= 2), and summer (n= 5) runs. 
The Chinook salmon were from the brood year 2011, except 
for 2 spring-run and 3 summer-run Chinook salmon that 
were from the brood year 2010. The remaining 3 CWTs were 
coded 09blank, indicating that they were from a hatchery in 
Oregon with no other information available. 
Each of the PIT-tagged Chinook salmon also may have 
had a CWT, and the CWT numbers that would have 
been used for these salmon (090587, 100201, 636417, 
and 220324 or 220325; Bumgarner 2 ; Rosenberger 3 ) did 
match numbers from CWTs recovered from the harbor 
porpoise’s forestomach (Table 1). Two of the PIT-tagged 
Chinook salmon would have received the same CWT num¬ 
ber (090587) because they were part of the same group 
(Rosenberger 3 ), and 2 tags with this CWT number were 
recovered from the harbor porpoise’s forestomach. Given 
that 5 of the recovered CWTs may have come from PIT- 
tagged Chinook salmon, the minimum number of indi¬ 
vidual juvenile Chinook salmon consumed by this harbor 
porpoise is 86. 
On the basis of the release dates of the juvenile Chinook 
salmon, the date and location of the stranding of the harbor 
porpoise, and the migration behavior of hatchery Chinook 
salmon, particularly those from the fall runs that tend to 
2 Bumgarner, J. 2018. Personal commun. Snake River Lab, Fish 
Program, Sci. Div., Wash. Dep. Fish Wildl., 401 South Cotton¬ 
wood St., Dayton, WA 99328. 
3 Rosenberger, S. 2018. Personal commun. Idaho Power Co., 1221 
West Idaho St., Boise, ID 83702. 
