This report summarizes
the objectives, tasks, and accomplishments of the Tucannon River Spring
Chinook Captive Broodstock Program during 2004.
The WDFW initiated a captive
broodstock program in 1997. The overall goal of the Tucannon River
captive broodstock program is for the short-term, and eventually long-term,
rebuilding of the Tucannon River spring chinook salmon population,
with the hope that natural production will sustain itself. The project
goal is to rear captive salmon selected from the supplementation program
to adults, spawn them, rear their progeny, and release approximately
150,000 smolts annually into the Tucannon River between 2003-2007.
These smolts, in combination with the current hatchery supplementation
program (132,000 smolts) and wild production, are expected to produce
600-700 returning adult spring chinook to the Tucannon River each
year from 2005-2010.
The captive broodstock
program collected fish from five (1997-2001) brood years (BY) with
additional fish collected from the 2002 BY to have extra males on
hand towards the end of the program. As of January 1, 2005, WDFW had
approximately 4 BY 2000, 191 BY 2001, and 186 BY 2002 fish on hand
at LFH.
The 2004 eggtake from the
1999 brood year (Age 5) was 9,768 eggs from eight ripe females. Egg
survival was 47%. Mean fecundity based on the five fully spawned females
was 1,490 eggs/female.
The 2004 eggtake from the
2000 brood year (Age 4) was 265,270 eggs from 169 ripe females. Egg
survival was 48%. Mean fecundity based on the 163 fully spawned females
was 1,598 eggs/female.
The 2004 eggtake from the
2001 brood year (Age 3) was 35,781 eggs from 28 ripe females. Egg
survival was 75%. Mean fecundity based on the 28 fully spawned fish
was 1,278 eggs/female.
The total 2004 eggtake
from the captive brood program was 310,819 eggs. A total of 151,917
dead eggs (49%) were removed with 158,902 live eggs remaining for
the program. An additional 18,028 dead eggs/fry (11.3%) were picked
at ponding leaving 140,874 fish for rearing. As of May 1, 2005 we
had 136,749 BY 2004 captive brood progeny on hand
During April 2005, WDFW
volitionally released 130,064 BY 2003 captive broodstock progeny smolts
from Curl Lake Acclimation Pond into the Tucannon River. These fish
were marked with a CWT and no fin clips in order to differentiate
them from the supplementation fish (CWT/Right Red VIE/No Finclip).
One thousand captive brood progeny smolts were PIT tagged to compare
their outmigration with smolts from the supplementation program (1,000
tagged). Monitoring their survival and future releases to adult returns,
along with future natural production levels, will determine the success
or failure of this captive broodstock program.
