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Title: Grande Ronde Endemic Spring Chinook Salmon Supplementation Project; Lostine River Operations and Maintenance 2003 Smolt Acclimation and Adult Return Report.

Abstract

The Nez Perce Tribe (NPT), through funding provided by the Bonneville Power Administration (BPA), has implemented a Chinook salmon supplementation program (250,000 smolts) on the Lostine River, a tributary to the Grande Ronde River of Oregon. The Grande Ronde Endemic Spring Chinook Salmon Supplementation project, which involves supplementation of the Upper Grande Ronde River and Catherine Creek in addition to the Lostine River, was established to prevent extirpation and increase the number of threatened Snake River spring/summer Chinook salmon (Oncorhynchus tshawytscha) returning to the Grande Ronde River. This report covers the seventh season (1997-2003) of adult Chinook salmon broodstock collection in the Lostine River and the fifth season (1999-2003) of acclimating the resultant progeny. Production of Lostine River spring Chinook salmon smolts currently occurs at Lookingglass Fish Hatchery (LGH). The Lostine River supplementation program utilizes two strategies to obtain egg source for production of smolts for supplementation: captive broodstock and conventional broodstock. The captive broodstock strategy involves (1) capture of natural juvenile spring Chinook salmon smolts from the Lostine River, (2) rearing those to adult and spawning them, and (3) rearing the resultant progeny for eventual acclimation and release back into the Lostine River. The conventional broodstock strategy involves (1)more » capture of natural and hatchery origin adults returning to the Lostine River, (2) holding those adults and spawning them, and (3) rearing the resultant progeny for acclimation and release back into the Lostine River. This report focuses on (1) the trapping and collection of adult spring Chinook salmon that return to the Lostine River, which provides the broodstock source for the conventional strategy and (2) the acclimation and release of juvenile spring Chinook salmon produced from the captive broodstock and conventional broodstock strategies. In 2003, acclimation of Lostine River spring Chinook salmon smolts occurred from March 3, 2003 through to April 14, 2003 and a total of 242,776 smolts were acclimated and released. These smolts were produced from the brood year (BY) 2001 egg source and included captive broodstock (141,860) and conventional broodstock (100,916) origin smolts that were all progeny of Lostine River spring Chinook salmon. Operation of the Lostine River adult monitoring and collection facility in 2003 began April 30th, the first Chinook was captured on May 16, 2003 and the last Chinook was captured on September 21, 2003. The weir and trap were removed on October 1, 2003. A total of 464 adult Chinook, including jacks, were captured during the season. The composition of the run included 239 natural origin fish and 225 hatchery supplementation fish. There were no identified 'stray' hatchery fish from other programs trapped. Of the fish captured, 45 natural and 4 hatchery supplementation adults were retained for broodstock and transported to LGH for holding and spawning, 366 adult Chinook were passed or transported above the weir to spawn naturally, and 49 hatchery origin adult jack Chinook were transported and outplanted in the Wallowa River and Bear Creek to spawn in underseeded habitat. Of the 49 adults retained for broodstock at Lookingglass Hatchery, 21 natural females and no hatchery origin females were represented in spawning. These females produced a total of 106,609 eggs at fertilization. Eye-up was 95.50% which yielded a total of 101,811 conventional program eyed eggs. The fecundity averaged 5,077 eggs per female. These eggs were incubated and at Lookingglass Hatchery until eyed stage. At eye they were transferred to Oxbow Hatchery where they were reared to the fingerling state at which time they were transported back to LGH until they were smolts in the spring of 2005. Captive brood program eggs/fish will be added to the conventional program eggs to make up the entire juvenile release for the Lostine River program in 2005.« less

Authors:
; ;  [1]
  1. Nez Perce Tribe
Publication Date:
Research Org.:
Bonneville Power Administration (BPA), Portland, OR (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
962224
Report Number(s):
P111162
R&D Project: 1998-007-02; TRN: US200916%%231
DOE Contract Number:
35994
Resource Type:
Technical Report
Resource Relation:
Related Information: document dated April 2004
Country of Publication:
United States
Language:
English
Subject:
13 HYDRO ENERGY; ADULTS; BONNEVILLE POWER ADMINISTRATION; FEMALES; FERTILIZATION; HABITAT; JUVENILES; MAINTENANCE; MONITORING; ORIGIN; PRODUCTION; PROGENY; REARING; RIVERS; SALMON; SEASONS; STREAMS; TRAPPING

Citation Formats

Zollman, Richard L., Eschler, Russell, and Sealey, Shawn. Grande Ronde Endemic Spring Chinook Salmon Supplementation Project; Lostine River Operations and Maintenance 2003 Smolt Acclimation and Adult Return Report.. United States: N. p., 2009. Web. doi:10.2172/962224.
Zollman, Richard L., Eschler, Russell, & Sealey, Shawn. Grande Ronde Endemic Spring Chinook Salmon Supplementation Project; Lostine River Operations and Maintenance 2003 Smolt Acclimation and Adult Return Report.. United States. doi:10.2172/962224.
Zollman, Richard L., Eschler, Russell, and Sealey, Shawn. 2009. "Grande Ronde Endemic Spring Chinook Salmon Supplementation Project; Lostine River Operations and Maintenance 2003 Smolt Acclimation and Adult Return Report.". United States. doi:10.2172/962224. https://www.osti.gov/servlets/purl/962224.
@article{osti_962224,
title = {Grande Ronde Endemic Spring Chinook Salmon Supplementation Project; Lostine River Operations and Maintenance 2003 Smolt Acclimation and Adult Return Report.},
author = {Zollman, Richard L. and Eschler, Russell and Sealey, Shawn},
abstractNote = {The Nez Perce Tribe (NPT), through funding provided by the Bonneville Power Administration (BPA), has implemented a Chinook salmon supplementation program (250,000 smolts) on the Lostine River, a tributary to the Grande Ronde River of Oregon. The Grande Ronde Endemic Spring Chinook Salmon Supplementation project, which involves supplementation of the Upper Grande Ronde River and Catherine Creek in addition to the Lostine River, was established to prevent extirpation and increase the number of threatened Snake River spring/summer Chinook salmon (Oncorhynchus tshawytscha) returning to the Grande Ronde River. This report covers the seventh season (1997-2003) of adult Chinook salmon broodstock collection in the Lostine River and the fifth season (1999-2003) of acclimating the resultant progeny. Production of Lostine River spring Chinook salmon smolts currently occurs at Lookingglass Fish Hatchery (LGH). The Lostine River supplementation program utilizes two strategies to obtain egg source for production of smolts for supplementation: captive broodstock and conventional broodstock. The captive broodstock strategy involves (1) capture of natural juvenile spring Chinook salmon smolts from the Lostine River, (2) rearing those to adult and spawning them, and (3) rearing the resultant progeny for eventual acclimation and release back into the Lostine River. The conventional broodstock strategy involves (1) capture of natural and hatchery origin adults returning to the Lostine River, (2) holding those adults and spawning them, and (3) rearing the resultant progeny for acclimation and release back into the Lostine River. This report focuses on (1) the trapping and collection of adult spring Chinook salmon that return to the Lostine River, which provides the broodstock source for the conventional strategy and (2) the acclimation and release of juvenile spring Chinook salmon produced from the captive broodstock and conventional broodstock strategies. In 2003, acclimation of Lostine River spring Chinook salmon smolts occurred from March 3, 2003 through to April 14, 2003 and a total of 242,776 smolts were acclimated and released. These smolts were produced from the brood year (BY) 2001 egg source and included captive broodstock (141,860) and conventional broodstock (100,916) origin smolts that were all progeny of Lostine River spring Chinook salmon. Operation of the Lostine River adult monitoring and collection facility in 2003 began April 30th, the first Chinook was captured on May 16, 2003 and the last Chinook was captured on September 21, 2003. The weir and trap were removed on October 1, 2003. A total of 464 adult Chinook, including jacks, were captured during the season. The composition of the run included 239 natural origin fish and 225 hatchery supplementation fish. There were no identified 'stray' hatchery fish from other programs trapped. Of the fish captured, 45 natural and 4 hatchery supplementation adults were retained for broodstock and transported to LGH for holding and spawning, 366 adult Chinook were passed or transported above the weir to spawn naturally, and 49 hatchery origin adult jack Chinook were transported and outplanted in the Wallowa River and Bear Creek to spawn in underseeded habitat. Of the 49 adults retained for broodstock at Lookingglass Hatchery, 21 natural females and no hatchery origin females were represented in spawning. These females produced a total of 106,609 eggs at fertilization. Eye-up was 95.50% which yielded a total of 101,811 conventional program eyed eggs. The fecundity averaged 5,077 eggs per female. These eggs were incubated and at Lookingglass Hatchery until eyed stage. At eye they were transferred to Oxbow Hatchery where they were reared to the fingerling state at which time they were transported back to LGH until they were smolts in the spring of 2005. Captive brood program eggs/fish will be added to the conventional program eggs to make up the entire juvenile release for the Lostine River program in 2005.},
doi = {10.2172/962224},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2009,
month = 3
}

Technical Report:

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  • The Nez Perce Tribe (NPT), through funding provided by the Bonneville Power Administration (BPA), has implemented a Chinook salmon supplementation program (250,000 smolts) on the Lostine River, a tributary to the Grande Ronde River of Oregon. The Grande Ronde Endemic Spring Chinook Salmon Supplementation project, which involves supplementation of the Upper Grande Ronde River and Catherine Creek in addition to the Lostine River, was established to prevent extirpation and increase the number of threatened Snake River spring/summer Chinook salmon (Oncorhynchus tshawytscha) returning to the Grande Ronde River. This report covers the eighth season (1997-2004) of adult Chinook salmon broodstock collectionmore » in the Lostine River and the sixth season (1999-2004) of acclimation of resulting Lostine River progeny. Production of Lostine River spring Chinook salmon smolts currently occurs at Lookingglass Fish Hatchery (LGH). The Lostine River supplementation program utilizes two strategies to obtain egg source for production of smolts for supplementation: captive broodstock and conventional broodstock. The captive broodstock strategy involves (1) capture of natural juvenile spring Chinook salmon smolts from the Lostine River, (2) rearing those to adult and spawning them, and (3) rearing the resultant progeny for eventual acclimation and release back into the Lostine River. The conventional broodstock strategy involves (1) capture of natural and hatchery origin adults returning to the Lostine River, (2) holding those adults and spawning them, and (3) rearing the resultant progency for acclimation and release back into the Lostine River. This report focuses on (1) the trapping and collection of adult spring Chinook salmon that return to the Lostine River, which provides the broodstock source for the conventional strategy and (2) the acclimation and release of juvenile spring Chinook salmon produced from the captive broodstock and conventional broodstock strategies. In 2004, acclimation of Lostine River spring Chinook salmon smolts occurred from March 1, 2004 through to April 14, 2004 and a total of 250,249 smolts were acclimated and released. These smolts were produced from the brood year (BY) 2002 egg source and included captive brood (133,781) and conventional (116,468) origin smolts that were all progeny of Lostine River spring Chinook salmon. Operation of the Lostine River adult monitoring and collection facility in 2004 began May 10, the first Chinook was captured on May 19, 2004 and the last Chinook was captured on September 16, 2004. The weir and trap were removed on October 1, 2004. A total of 1,091 adult Chinook, including jacks, were captured during the season. The composition of the run included 299 natural origin fish and 792 hatchery supplementation fish. There were no identified 'stray' hatchery fish from other programs trapped. Of the fish captured, 46 natural and 69 hatchery supplementation adults were retained for broodstock and transported to Lookingglass Hatchery for holding and spawning, 537 adult Chinook were passed or transported above the weir to spawn naturally, and 447 hatchery origin adult Chinook were transported and outplanted in the Wallowa River and Bear Creek to spawn in underseeded habitat. Of the 107 adults retained (eight additional hatchery females were collected and then later returned to the Lostine River to spawn naturally) for broodstock at Lookingglass Hatchery, 22 natural females and 30 supplementation females were represented in spawning. These females produced a total of 221,889 eggs at fertilization. Eye-up was 94.9% which yielded a total of 210,661 conventional program eyed eggs. The fecundity averaged 4,267 eggs per female. These eggs were incubated and at Lookingglass Hatchery until eyed stage and then transferred to Oxbow Hatchery where they will be reared to the fingerling stage. They will then be transported back to LGH and reared to the smolt stage and then transported to the Lostine acclimation facility for release in the spring of 2006. Captive brood program eggs/fish will be added to the conventional program eggs to make up the entire juvenile release for the Lostine River program in 2006.« less
  • The Nez Perce Tribe (NPT), through funding provided by the Bonneville Power Administration (BPA), has implemented a Chinook salmon supplementation program (250,000 smolts) on the Lostine River, a tributary to the Grande Ronde River of Oregon. The Grande Ronde Endemic Spring Chinook Salmon Supplementation project, which involves supplementation of the Upper Grande Ronde River and Catherine Creek in addition to the Lostine River, was established to prevent extirpation and increase the number of threatened Snake River spring/summer Chinook salmon (Oncorhynchus tshawytscha) returning to the Grande Ronde River. This report covers the tenth season (1997-2006) of adult Chinook salmon broodstock collectionmore » in the Lostine River and the eighth season (1999-2006) of acclimation of resulting Lostine River progeny. Production of Lostine River spring Chinook salmon smolts currently occurs at Lookingglass Fish Hatchery (LGH). The Lostine River supplementation program utilizes two strategies to obtain egg source for production of smolts for supplementation: captive broodstock and conventional broodstock. The captive broodstock strategy involves (1) capture of natural juvenile spring Chinook salmon smolts from the Lostine River, (2) rearing those to adult and spawning them, and (3) rearing the resultant progeny for eventual acclimation and release back into the Lostine River. The conventional broodstock strategy involves (1) capture of natural and hatchery origin adults returning to the Lostine River, (2) holding those adults and spawning them, and (3) rearing the resultant progeny for acclimation and release back into the Lostine River. This report focuses on (1) the trapping and collection of adult spring Chinook salmon that return to the Lostine River, which provides the broodstock source for the conventional strategy and (2) the acclimation and release of juvenile spring Chinook salmon produced from the captive broodstock and conventional broodstock strategies In 2006, acclimation of Lostine River spring Chinook salmon smolts occurred from February 27, 2006 through to April 10, 2006 and a total of 240,568 smolts were acclimated and released. These smolts were produced from the brood year (BY) 2004 egg source and included captive brood (40,982) and conventional (199,586) origin smolts that were all progeny of Lostine River spring Chinook salmon. Operation of the Lostine River adult monitoring and collection facility in 2006 began May 15th, the first Chinook was captured on June 14, 2006 and the last Chinook was captured on September 27, 2006. The weir and trap were removed on October 1, 2006. A total of 534 adult Chinook, including jacks, were captured during the season. The composition of the run included 205 natural origin fish and 329 hatchery supplementation fish. There were no identified 'stray' hatchery fish from other programs trapped. Of the fish captured, 33 natural and 120 hatchery supplementation adults were retained for broodstock and transported to LGH for holding and spawning and 397 adult Chinook were passed or transported above the weir to spawn naturally. In 2006, no hatchery origin adult Chinook were transported and out planted in the Wallowa River and Bear Creek to spawn in under seeded habitat. In order to meet egg take goals for the conventional portion of the program, a determination was made that approximately 147 adults were needed for broodstock. As a result 16 (8 males and 8 females) of the 153 fish collected for broodstock were returned to the Lostine River to spawn naturally. Females that were spawned and provided the brood source were made up of 12 natural females and 45 supplementation females. One of these females tested positive for high levels of Bacterial Kidney Disease and consequently this females eggs were destroyed. The remaining females produced a total of 241,372 eggs at fertilization. Eye-up was 85.47% which yielded a total of 206,309 conventional program eyed eggs. The fecundity averaged 4,162 eggs per female. The brood year 2006 eggs will be incubated and reared at Lookingglass Hatchery until they are smolts in the spring of 2008. Captive brood program eggs/fish will be added to the conventional program eggs to make up the entire juvenile release for the Lostine River program in 2008.« less
  • The Nez Perce Tribe (NPT), through funding provided by the Bonneville Power Administration (BPA), has implemented a Chinook salmon supplementation program (250,000 smolts) on the Lostine River, a tributary to the Grande Ronde River of Oregon. The Grande Ronde Endemic Spring Chinook Salmon Supplementation project, which involves supplementation of the Upper Grande Ronde River and Catherine Creek in addition to the Lostine River, was established to prevent extirpation and increase the number of threatened Snake River spring/summer Chinook salmon (Oncorhynchus tshawytscha) returning to the Grande Ronde River. This report covers the eleventh season (1997-2007) of adult Chinook salmon broodstock collectionmore » in the Lostine River and the ninth season (1999-2007) of acclimation of resulting Lostine River progeny. Production of Lostine River spring Chinook salmon smolts currently occurs at Lookingglass Fish Hatchery (LGH). The Lostine River supplementation program utilizes two strategies to obtain egg source for production of smolts for supplementation: captive broodstock and conventional broodstock. The captive broodstock strategy involves (1) capture of natural juvenile spring Chinook salmon smolts from the Lostine River, (2) rearing those to adult and spawning them, and (3) rearing the resultant progeny for eventual acclimation and release back into the Lostine River. The conventional broodstock strategy involves (1) capture of natural and hatchery origin adults returning to the Lostine River, (2) holding those adults and spawning them, and (3) rearing the resultant progeny for acclimation and release back into the Lostine River. This report focuses on (1) the trapping and collection of adult spring Chinook salmon that return to the Lostine River, which provides the broodstock source for the conventional strategy and (2) the acclimation and release of juvenile spring Chinook salmon produced from the captive broodstock and conventional broodstock strategies In 2007, acclimation of Lostine River spring Chinook salmon smolts occurred from 3/5/07 through to 4/17/07 and a total of 230,010 smolts were acclimated and released. These smolts were produced from the brood year (BY) 2005 egg source and included captive brood (24,604) and conventional (205,406) origin smolts that were all progeny of Lostine River spring Chinook salmon. Operation of the Lostine River adult monitoring and collection facility in 2007 began May 14th. The first Chinook was captured on June 2, 2007 and the last Chinook was captured on September 25, 2007. The weir and trap were removed on October 1, 2007. A total of 637 adult Chinook, including jacks, were captured during the season. The composition of the run included 240 natural origin fish and 397 hatchery supplementation fish. There were no identified 'stray' hatchery fish from other programs trapped. Of the fish captured, 41 natural and 81 hatchery supplementation adults were retained for broodstock and transported to LGH for holding and spawning, 403 adult Chinook were passed or transported above the weir to spawn naturally, and only hatchery origin jack Chinook were transported and outplanted in the Wallowa River and Bear Creek in underseeded habitat. Of the 122 adult fish retained for broodstock, 20 natural females and 40 supplementation females were represented in spawning. The eggs from these females produced a total of 267,350 eggs at fertilization. Eye-up was 86.73% which yielded a total of 231,882 conventional program eyed eggs. The fecundity averaged 4,456 eggs per female. These eggs will be incubated and reared at Lookingglass Hatchery until they are smolts in the spring of 2009. Captive brood program eggs/fish will be added to the conventional program eggs to make up the entire juvenile release for the Lostine River program in 2009. Due to the success of the 2007 egg collection, the number of fish produced exceeded program needs and facility capabilities. As a result, there are plans to outplant fry in 2008 and parr in early 2009 to underseeded habitat in the Wallowa River.« less
  • Anadromous salmonid stocks have declined in both the Grande Ronde River Basin (Lower Snake River Compensation Plan (LSRCP) Status Review Symposium 1998) and in the entire Snake River Basin (Nehlsen et al. 1991), many to the point of extinction. The Grande Ronde River Basin historically supported large populations of fall and spring chinook (Oncorhynchus tshawytscha), sockeye (O. nerka), and coho (O. kisutch) salmon and steelhead trout (O. mykiss) (Nehlsen et al. 1991). The decline of chinook salmon and steelhead populations and extirpation of coho and sockeye salmon in the Grande Ronde River Basin was, in part, a result of constructionmore » and operation of hydroelectric facilities, over fishing, and loss and degradation of critical spawning and rearing habitat in the Columbia and Snake River basins (Nehlsen et al. 1991). Hatcheries were built in Oregon, Washington and Idaho under the Lower Snake River Compensation Plan (LSRCP) to compensate for losses of anadromous salmonids due to the construction and operation of the lower four Snake River dams. Lookingglass Hatchery (LGH) on Lookingglass Creek, a tributary of the Grande Ronde River, was completed under LSRCP in 1982 and has served as the main incubation and rearing site for chinook salmon programs for Grande Ronde and Imnaha rivers in Oregon. Despite these hatchery programs, natural spring chinook populations continued to decline resulting in the National Marine Fisheries Service (NMFS) listing Snake River spring/summer chinook salmon as ''threatened'' under the federal Endangered Species Act (1973) on 22 April 1992. Continuing poor escapement levels and declining population trends indicated that Grande Ronde River basin spring chinook salmon were in imminent danger of extinction. These continuing trends led fisheries co-managers in the basin to initiate the Grande Ronde Endemic Spring Chinook Salmon Supplementation Program (GRESCSSP) in order to prevent extinction and preserve options for use of endemic fish stocks in future artificial propagation programs. The GRESCSSP was implemented in three Grande Ronde River basin tributaries; the Lostine and upper Grande Ronde rivers and Catherine Creek. The GRESCSSP employs two broodstock strategies utilizing captive and conventional brood sources. The captive brood program began in 1995, with the collection of parr from the three tributary areas. The conventional broodstock component of the program began in 1997 with the collection of natural adults returning to these tributary areas. Although LGH was available as the primary production facility for spring chinook programs in the Grande Ronde Basin, there were never any adult or juvenile satellite facilities developed in the tributary areas that were to be supplemented. An essential part of the GRESCSSP was the construction of adult traps and juvenile acclimation facilities in these tributary areas. Weirs were installed in 1997 for the collection of adult broodstock for the conventional component of the program. Juvenile facilities were built in 2000 for acclimation of the smolts produced by the captive and conventional broodstock programs and as release sites within the natural production areas of their natal streams. The Confederated Tribes of the Umatilla Indian Reservation (CTUIR) operate both the juvenile acclimation and adult trapping facilities located on Catherine Creek and the upper Grande Ronde River under this project. The Nez Perce Tribe (NPT) operate the facilities on the Lostine River under a sister project. Hatcheries were also built in Oregon, Washington and Idaho under the LSRCP to compensate for losses of summer steelhead due to the construction and operation of the lowest four Snake River dams. Despite these harvest-driven hatchery programs, natural summer steelhead populations continued to decline as evidenced by declining counts at Lower Granite Dam since 1995 (Columbia River Data Access in Real Time, DART) and low steelhead redd counts on index streams in the Grande Ronde Basin. Because of low escapement the Snake River summer steelhead were listed as threatened under the Endangered Species Act of 1973 by the National Marine Fisheries Service (NMFS) on 18 August, 1997. Co-managers have also discontinued off-station releases of juvenile Wallowa stock (non-endemic) hatchery summer steelhead into Catherine Creek in 1998 and the upper Grande Ronde River in 1999. Data are lacking on adult return numbers and the genetic make-up of populations that return to tributaries of the Grande Ronde River basin, Catherine Creek and the upper Grande Ronde River specifically. Adult fish weirs are in place on Catherine Creek and the upper Grande Ronde River and data on summer steelhead populations in those areas are collected.« less
  • There were 2 acclimation periods at the Catherine Creek Acclimation Facility (CCAF) in 2004. During the early acclimation period, 92,475 smolts were delivered from Lookingglass Hatchery (LGH) on 8 March. This group was comprised entirely of progeny from the captive broodstock program. The size of the fish at delivery was 23.1 fish/lb. Volitional releases began 15 March 2004 and ended 22 March with an estimated total (based on PIT tag detections of 1,475) of 8,785 fish leaving the raceways. This was 9.5% of the total fish delivered. Fish remaining in the raceways after volitional release were forced out. Hourly detectionsmore » of PIT-tagged fish showed that most of the fish left between 1200 and 2000 hours which was similar to the hourly temperature profile. The size of the fish just before the volitional release was 23.1 and the size of the fish remaining just before the forced release was 23.5 fish/lb. The total mortality for the acclimation period was 62 (0.07 %). The total number of fish released from the acclimation facility during the early period was 92,413. During the second acclimation period 70,977 smolts were delivered from LGH on 24 March. This group was comprised entirely of progeny from the conventional broodstock program. The size of the fish at delivery was 23.4 fish/lb. Volitional releases began 30 March 2004 and ended 12 April with an estimated total (based on PIT tag detections of 3,632) of 49,147 fish leaving the raceways. This was 69.2% of the total fish delivered. Fish remaining in the raceways after volitional release were forced out. Hourly detections of PIT-tagged fish showed that most of the fish left between 1200 and 2000 hours which was similar to the hourly temperature profile. The size of the fish just before the volitional release was 23.4 and the size of the fish remaining just before the forced release was 23.9 fish/lb. The total mortality for the acclimation period was 18 (0.03 %). The total number of fish released from the acclimation facility during the late period was 70,959.« less