This report summarizes
activities by the Washington Department of Fish and Wildlife's (WDFW)
Lower Snake River Hatchery Evaluation Program from April 16, 2000
to April 15, 2001. Fall chinook salmon broodstock were obtained from
two sources: voluntary returns to the Lyons Ferry Hatchery (LFH) ladder
and fish trapped and transported to LFH from Lower Granite (LGR) Dam.
Only coded-wire tagged (CWT), blank wire tagged (BWT), or ventral
fin clipped salmon were collected at LGR Dam and transported to the
hatchery. Prior to spawning, fall chinook which volunteered into LFH
were sorted to determine sex. At that time, 12 fish with visible implant
elastomer (VIE) tags (indicating returns from upstream acclimated
releases) were transported above LGR Dam and released in accordance
with the Nez Perce Tribe’s (NPT) request. The total number of
fall chinook processed at spawning in 2000 was 4,831, including 2,379
adults and jacks that had voluntarily returned to the hatchery, and
2,452 salmon transported from trapping operations at LGR Dam. There
were an additional 272 fish that were sacrificed at LGR Dam for CWT
recovery that will also be included in this report.
As in previous
years, we were able to evaluate straying to the Snake River by using
CWTs, BWTs, and ventral fin clips recovered from fish trapped at LFH,
fish trapped and hauled to LFH from LGR Dam, and fish sacrificed at
LGR Dam. In 2000, there were 249 strays processed at LFH. The majority
of strays (240 fish) were from hatchery releases in the Umatilla River.
There were an additional two hatchery recoveries from fish released
in the Klickitat River. The remaining seven were strays from other
locations.
In 2000, 21 coho
(17 males and 4 females) were trapped incidentally at LFH. One fish
was returned to the Snake River at LFH and two fish were transported
above LGR Dam and released. Ten fish were transferred to the NPT and
the remaining eight coho died before they could be transferred.
Fall chinook were
spawned at LFH from October 24 to December 5, 2000. Peak of spawning
was November 7 and 8. Coded-wire tags were removed from marked hatchery
fish and read to determine the fish’s origin prior to mixing
of gametes. We read 53% of the CWTs associated with red VIE tagged
(known LFH) fish and 100% of the wire detected from other fish which
were slated for spawning. Matings consisted of single female/single
male lots with a backup male. Only salmon verified to be of LFH/Snake
River origin were used for broodstock. All hatchery strays and unmarked
fish were spawned together as “strays.” In addition, CWTs
were read from unspawned fish to determine their origin.
In 2000, egg take
from all fish was 4,190,338. The final egg take from LFH/Snake River
origin broodstock was 3,576,956 green eggs. As a precautionary measure,
53,176 green eggs from LFH/Snake River origin females which tested
ELISA positive for Bacterial Kidney Disease were destroyed prior to
eye-up. This left 3,523,780 green eggs available for production. At
eye-up, 3,365,268 eggs were picked and loss was estimated at 4.5%.
On December 7, we transferred 115,891 eyed eggs to Idaho Fish and
Game as part of the Idaho Power Company mitigation agreement. The
estimated number of LFH/Snake River origin fry ponded was 3,158,689
fish. Stray or unmarked fall chinook from the 2000 brood produced
613,382 green eggs, 213,785 of which were destroyed. Loss to the eyed
stage of the remaining 399,597 eggs was 2.9% leaving 388,157 stray
origin eggs that were shipped to Klickitat Hatchery.
Sex, age, and
mean length information was compiled for LFH/Snake River origin fall
chinook salmon adults and jacks. These returns continued to be dominated
by younger age classes. Females dominated the older age class of returning
LFH/Snake River origin salmon because few males return at age 5 or
older.
LFH released 196,643
subyearling (1999 brood) fall chinook salmon from the hatchery on
May 26, 2000. Subyearling releases from LFH were 100% adipose clipped
(marked) and coded-wire tagged. In addition, the NPT released 2,183,477
subyearling (1999 brood) fall chinook; two releases from Big Canyon
and Captain John acclimation facilities, and a single release from
Pittsburg Landing acclimation facility May 20 through June 26. Fish
released from Big Canyon and Pittsburg Landing acclimation sites were
not tagged or marked by the NPT. The early release at Captain John
was 40% marked with CWT, but without an associated fin clip. The late
release was 50% marked in the same fashion.
In 2001, all yearling
fall chinook salmon released from LFH and the acclimation sites were
adipose clipped (marked), coded-wire tagged, and elastomer tagged.
During April 1-20, LFH volitionally released 338,757 yearling (1999
brood) fall chinook salmon from the hatchery. The LFH yearling release
was tagged with a red VIE tag in the clear tissue behind the left
eye (LR). Releases were delayed to synchronize with increasing flows
in a drought year. The NPT released a total of 318,932 fall chinook
yearlings (1999 brood) April 4-13, 2001 from acclimation facilities
upstream of LGR Dam. Fish from Pittsburg Landing had right green (RG)
elastomers, fish from Big Canyon had left green (LG) elastomers, and
fish from Captain John had left blue (LB) elastomers. Also in 2001,
subyearlings were barged from LFH to below Bonneville Dam, released
from three acclimation sites above LGR Dam, and directly released
into the Snake River below Hells Canyon Dam.
Surveys were conducted
to count fall chinook redds in the Tucannon River. In 2000, we observed
19 redds (2.1 redds/km below Rk 9.6) and 18 carcasses. Five of the
carcasses originated from Umatilla Hatchery, nine originated from
Lyons Ferry Hatchery, and one was of unknown origin (skeletal remains).
The Umatilla component was 27.8%, nearly a two-fold increase from
what we have observed in the last two years. The remaining three fish
were unmarked and of natural origin based on scale samples.
We are unable
to account for 19.4 percent (3,196 salmon) of fall chinook escapement
past Ice Harbor (IHR) Dam in 2000. These estimates are calculated
as the difference between the number of fish crossing IHR Dam and
the numbers of fish entering LFH, spawning in the Tucannon River,
and counted at LGR Dam.
Recommendations
for the future:
1) pursue more
aggressive hazing to deter/decrease the avian predation before tagging
occurs in September;
2) pursue additional
funding to build additional raceways or rearing ponds at LFH to
address fish density and fish health concerns;
3) propose outlets
for additional fish produced at LFH like a direct stream release
of subyearlings paired with the release of subyearlings out of Captain
John acclimation facility to compare survival between release strategies,
or encourage IDFG and Idaho Power Company to aggressively develop
Oxbow Hatchery for future chinook releases;
4) look at ways
to reduce the incidence of BKD at LFH;
5) summarize
adult returns for LFH origin fall chinook beginning with the 1990
brood released at LFH and include in a future (2001) report;
6) complete
a cooperative report with fall chinook co-managers in the Snake
River basin to determine the effectiveness of programs to meet LSRCP
goals and assess the success of each release site by looking at
smoltto- adult survivals;
7) discontinue
ATPase and Cortisol sampling until the existing data has been summarized
in an upcoming (2002) report;
8) examine the
size, time, and type of release that may be causing excess jacks;
and
9) summarize
adult and jack return data by release type to evaluate age and sex
composition.
