A Comparison of Run Timing, Spawn Timing and Spawning Distribution of Natural and Hatchery Spring Chinook Salmon Oncorhynchus Tshawytscha in the Imnaha River, Oregon

A Comparison of Run Timing, Spawn Timing and Spawning Distribution of Natural and Hatchery Spring Chinook Salmon Oncorhynchus Tshawytscha in the Imnaha River, Oregon PDF Author: Timothy L. Hoffnagle
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Category : Chinook salmon
Languages : en
Pages : 22

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Monitoring the Reproductive Success of Naturally Spawning Hatchery and Natural Spring Chinook Salmon in the Wenatchee River, 2008-2009 Progress Report

Monitoring the Reproductive Success of Naturally Spawning Hatchery and Natural Spring Chinook Salmon in the Wenatchee River, 2008-2009 Progress Report PDF Author:
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ISBN:
Category :
Languages : en
Pages : 84

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We investigated differences in the statistical power to assign parentage between an artificially propagated and wild salmon population. The propagated fish were derived from the wild population, and are used to supplement its abundance. Levels of genetic variation were similar between the propagated and wild groups at 11 microsatellite loci, and exclusion probabilities were>0.999999 for both groups. The ability to unambiguously identify a pair of parents for each sampled progeny was much lower than expected, however. Simulations demonstrated that the proportion of cases the most likely pair of parents were the true parents was lower for propagated parents than for wild parents. There was a clear relationship between parentage assignment ability and the degree of linkage disequilibrium, the estimated effective number of breeders that produced the parents, and the size of the largest family within the potential parents. If a stringent threshold for parentage assignment was used, estimates of relative fitness were biased downward for the propagated fish. The bias appeared to be largely eliminated by either fractionally assigning progeny among parents in proportion to their likelihood of parentage, or by assigning progeny to the most likely set of parents without using a statistical threshold. We used a DNA-based parentage analysis to measure the relative reproductive success of hatchery- and natural-origin spring Chinook salmon in the natural environment. Both male and female hatchery-origin fish produced far fewer juvenile progeny per parent when spawning naturally than did natural origin fish. Differences in age structure, spawning location, weight and run timing were responsible for some of the difference in fitness. Male size and age had a large influence on fitness, with larger and older males producing more offspring than smaller or younger individuals. Female size had a significant effect on fitness, but the effect was much smaller than the effect of size on male fitness. For both sexes, run time had a smaller but still significant effect on fitness, with earlier returning fish favored. Spawning location within the river had a significant effect on fitness for both males and females, and for females explained most of the reduced fitness observed for hatchery fish in this population. While differences have been reported in the relative reproductive success of hatchery and naturally produced salmonids Oncorhynchus spp., factors explaining the differences are often confounded. We examined the spawning site habitat and redd structure variables of hatchery and naturally produced spring Chinook salmon O. tshawytscha of known size that spawned in two tributaries of the Wenatchee River. We controlled for variability in spawning habitat by limiting our analysis to redds found within four selected reaches. No difference in the instantaneous spawner density or location of the redd in the stream channel was detected between reaches. Within each reach, no difference in the fork length or weight of hatchery and naturally produced fish was detected. While most variables differed between reaches, we found no difference in redd characteristics within a reach between hatchery and naturally produced females. Correlation analysis of fish size and redd characteristics found several weak but significant relationships suggesting larger fish contract larger redds in deeper water. Spawner density was inversely related to several redd structure variables suggesting redd size may decrease as spawner density increases. Results should be considered preliminary until samples size and statistical power goals are reached in future years. Trends in relative reproductive success of hatchery and naturally produced spring Chinook salmon Oncorhynchus tshawytscha in the Wenatchee Basins suggest females that spawn in the upper reaches of the tributaries produced a great number of offspring compared to females that spawn in the lower reaches of the tributaries. To better understand this trend, redd microhabitat data was collected from spring Chinook salmon that spawned in the Chiwawa River and Nason Creek, the primary spawning tributaries in the Wenatchee Basin. The objective of the study was to examine the influence of habitat and spawner density on spawning site and redd structure characteristics. We analyzed 27 variables of redd microhabitat data collected from the upper and lower most reaches of each study stream. In both streams, we found redds in the upper most reaches to be significantly larger (length and width) and deeper (bowl depth). Spawner density was significantly greater in the lower Chiwawa River compared to the upper reach. No difference in spawner density was detected between reaches in Nason Creek (P = 0.54). Data should be considered preliminary until sample size goals are achieved.

Spawning Success of Hatchery Spring Chinook Salmon Outplanted as Adults in the Clearwater River Basin, Idaho, 2001

Spawning Success of Hatchery Spring Chinook Salmon Outplanted as Adults in the Clearwater River Basin, Idaho, 2001 PDF Author:
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Category :
Languages : en
Pages : 73

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The study described in this report evaluated spawning distribution, overlap with naturally-arriving spawners, and pre-spawning mortality of spring chinook salmon, Oncorhynchus tshawytscha, outplanted as adults in the Clearwater River Subbasin in 2001. Returns of spring chinook salmon to Snake River Basin hatcheries and acclimation facilities in 2001 exceeded needs for hatchery production goals in Idaho. Consequently, management agencies including the U.S. Fish and Wildlife Service (FWS), Idaho Department of Fish and Game (IDFG) and Nez Perce Tribe (NPT) agreed to outplant chinook salmon adults as an adaptive management strategy for using hatchery adults. Adult outplants were made in streams or stream sections that have been typically underseeded with spawners. This strategy anticipated that outplanted hatchery chinook salmon would spawn successfully near the areas where they were planted, and would increase natural production. Outplanting of adult spring chinook salmon from hatcheries is likely to be proposed in years when run sizes are similar to those of the 2001 run. Careful monitoring of results from this year's outplanting can be used to guide decisions and methods for future adult outplanting. Numbers of spring chinook salmon outplanted was based on hatchery run size, hatchery needs, and available spawning habitat. Hatcheries involved in outplanting in the Clearwater Basin included Dworshak National Fish Hatchery, Kooskia National Fish Hatchery, Clearwater Anadromous Fish Hatchery, and Rapid River Fish Hatchery. The NPT, IDFG, FWS, and the National Marine Fisheries Service (NMFS) agreed upon outplant locations and a range of numbers of spring chinook salmon to be outplanted (Table 1). Outplanting occurred mainly in the Selway River Subbasin, but additional outplants were made in tributaries to the South Fork Clearwater River and the Lochsa River (Table 1). Actual outplanting activities were carried out primarily by the NPT with supplemental outplanting done in the Lochsa basin by IDFG. Fish were trucked from the hatcheries to outplant sites.

Run Timing, Fat Content and Maturity of Spring- and Fall-run Klamath River Chinook Salmon (Oncorhynchus Tshawytscha)

Run Timing, Fat Content and Maturity of Spring- and Fall-run Klamath River Chinook Salmon (Oncorhynchus Tshawytscha) PDF Author: James W. Hearsey
Publisher:
ISBN:
Category : Chinook salmon
Languages : en
Pages : 138

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Factors Influencing the Return of Fall Chinook Salmon (Oncorhynchus Tshawytscha) to Spring Creek Hatchery

Factors Influencing the Return of Fall Chinook Salmon (Oncorhynchus Tshawytscha) to Spring Creek Hatchery PDF Author: Charles O. Junge
Publisher:
ISBN:
Category : Chinook salmon
Languages : en
Pages : 40

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Gulkana River Chinook Salmon Spawning Distribution and Run Timing, 2013-2015

Gulkana River Chinook Salmon Spawning Distribution and Run Timing, 2013-2015 PDF Author: Corey J. Schwanke
Publisher:
ISBN:
Category : Chinook salmon
Languages : en
Pages : 40

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Chinook salmon were radiotagged near the confluence of the Gulkana and Copper rivers from 2013-2015 to determine run timing and spawning distribution in the Gulkana River. The main goal was estimating what proportion of the Chinook salmon escapement spawned above an ADF&G operated counting tower located approximately 79.5 rkm up the Gulkana River. Age, sex, and length composition of the escapement was also estimated. A total of 412 Chinook salmon were radiotagged from 2013?2015 using dip nets and hook and line as capture gear. The proportion of Chinook salmon that spawned above the ADF&G counting tower was 0.51 (SE = 0.072) in 2013, 0.45 (SE = 0.073) in 2014, and 0.54 (SE = 0.038) in 2015. Fish spawning above the ADF&G counting tower had a slightly earlier run timing than fish spawning below the counting tower with annual mean dates of passage past the lowest inriver tracking station being 0?7 days earlier. Further examining run timing by river reach, Chinook salmon that spawned in the tributaries and upper mainstem of the Gulkana River had earlier run timing than those spawning in the middle to lower mainstem. The estimated percentage of females that spawned above the counting tower varied by year. Females comprised an estimated 53% (SE = 6%) of the escapement in 2013, 29% (SE = 10%) in 2014, and 51% (SE = 4%) in 2015. Age-1.3 Chinook salmon was the most abundant age class, accounting for 81% (SE = 5%) of the estimated escapement in 2013, 48% (SE = 6%) in 2014, and 88% (SE = 3%) in 2015. Chinook salmon in the length class 751-850 mm mid eye to tail fork accounted for the majority of the estimated annual escapement, ranging between 46% (SE = 6%) and 63% (SE = 4%). This study found several positive relationships with fish traits (e.g., sex, length, and run timing) and spawning success specific to the Gulkana River. Male fish, longer fish, and fish with earlier run timings all had better chances of spawning during this study.

Straying of Late-Fall-run Chinook Salmon from the Coleman National Fish Hatchery Into the Lower American River, California

Straying of Late-Fall-run Chinook Salmon from the Coleman National Fish Hatchery Into the Lower American River, California PDF Author: Gina R. Lasko
Publisher:
ISBN:
Category :
Languages : en
Pages : 94

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Pacific salmon (Oncorhynchus spp.) are generally anadromous fishes that spawn in fresh water. When young salmon have grown and matured to what is called the smolt stage (ocean ready), they move into the ocean to mature and grow into adulthood. When they have reached sexual maturity, they return to fresh water to spawn and then die. Salmon typically home to their natal streams when returning to fresh water to spawn. Straying, however, is a natural behavior for a small fraction of individuals in a population, and may even have an adaptive advantage under some circumstances. Straying can also occur as a result of various factors including natural habitat disruption, modification of the watershed, or human intervention in salmonid reproduction. In the winter of 2006/2007, tens of thousands of late-fall-run Chinook salmon (Oncorhynchus tshawytscha) reared in the Coleman National Fish Hatchery, a US Fish and Wildlife Service facility on Battle Creek in the upper Sacramento River basin, were released at several downstream locations as part of a Sacramento-San Joaquin River Delta survival study. Two years later, in the winter of 2008/2009, at the end of the annual Department of Fish and Game lower American River escapement survey for fall-run Chinook salmon, a new pulse of fish was found to be spawning in the American River. These fish turned out to be stray late-fall-run Chinook salmon from the Coleman National Fish Hatchery, spawning in the American River where the fall-run Chinook salmon were completing their spawning run. Late-fall-run Chinook salmon have not been known to spawn in the American River and understanding the reason for this unusual behavior was the basis for this project. Currently the only run of Chinook salmon in the lower American River is the fall-run. The Department does not want late-fall-run Chinook salmon to establish themselves in the river because of potential disruption of fall-run Chinook salmon nest success due to an overlap in run timing, potential interbreeding, and limited available spawning habitat. This study was based on the hypothesis that salmon released in close proximity to the mouth of the American River are more likely to stray into the river during their return spawning migration than fish released farther from the river's mouth. Coded-wire tag inland return data from for the 2006 brood year of late-fall-run Chinook collected from 2007/2008 through 2010/2011 were used for this study. The tags were collected primarily from salmon found during river escapement surveys and those that returned to hatcheries in the Sacramento River watershed. The return data were analyzed using Chi-square statistical analyses to determine if there was a difference in the number of salmon straying into the American River with respect to the distance they were released from the mouth of that river, and a Spearman noncollated rank analysis was used to describe the overall relationship between release distance from the American River and percent straying into the river. Results indicated that straying did increase with proximity of release location to the mouth of the American River and with respect to downstream releases in general. No salmon released in the vicinity of the Coleman National Fish Hatchery were recovered in the lower American River. This study indicates that release location should be carefully evaluated if future downstream releases are conducted by Sacramento River watershed hatcheries.

Comparison of Spawning Areas and Times for Two Runs of Chinook Salmon (Oncorhynchus Tshawtscha) in the Kenai River, Alaska

Comparison of Spawning Areas and Times for Two Runs of Chinook Salmon (Oncorhynchus Tshawtscha) in the Kenai River, Alaska PDF Author: Carl V. Burger
Publisher:
ISBN:
Category : Chinook salmon
Languages : en
Pages : 42

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Run Timing and Spawning Distribution of Copper River Chinook Salmon, 2019-2021

Run Timing and Spawning Distribution of Copper River Chinook Salmon, 2019-2021 PDF Author: Corey J. Schwanke
Publisher:
ISBN:
Category : Chinook salmon
Languages : en
Pages : 0

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A total of 1,975 radio tags were placed in migrating Chinook salmon Oncorhynchus tshawytscha in the Copper River from 2019 through 2021 to examine spawning distribution and run timing. Chinook salmon were captured with fish wheels in the Lower Copper River near Baird Canyon and tracked to upriver destinations with 10 fixed-tracking stations and a series of aerial surveys. Spawning distribution was estimated for 6 major spawning tributaries/areas each year using a weighting process. Estimated annual proportions of the escapement ranged from 0.19 to 0.24 for the Upper Copper River area, 0.19–0.27 for the Gulkana River, 0.01–0.05 for the Tazlina River, 0.10–0.19 for the Tonsina River, 0.19–0.28 for the Chitina River, and was 0.14 all 3 years for the Klutina River. Estimated annual abundances for the 6 major spawning tributary/areas from 2019 through 2021 were 3,410–8,369 for the Upper Copper River area, 4,419–6,548 for the Gulkana River, 289–961 for the Tazlina River, 2,171–4,591 for the Tonsina River, 3,535–9,767 for the Chitina River, and 2,608–4,909 for the Klutina River. The annual estimated proportions of the total escapement that returned to 1 of the 9 original aerial index streams ranged from 0.39 to 0.47. The estimated annual proportion of the Gulkana River fish that spawned above the Alaska Department of Fish & Game (ADF&G) counting tower ranged from 0.58 to 0.68. Run timing patterns were similar during all 3 years with the Upper Copper River fish having the earliest run timings, followed by the Gulkana, Chitina, Tazlina, Tonsina, and Klutina Rivers. A secondary analysis was performed weighting each radiotagged fish using adaptive resolution imaging sonar (ARIS) estimates of “large” fish, which are all presumed to be Chinook salmon. These results are presented in this report as Appendix A.

Spawning Areas and Abundance of Chinook Salmon (Oncorhynchus Tshawytscha) In the Columbia River Basin

Spawning Areas and Abundance of Chinook Salmon (Oncorhynchus Tshawytscha) In the Columbia River Basin PDF Author: Leonard A. Fulton
Publisher: Forgotten Books
ISBN: 9781333761677
Category : Sports & Recreation
Languages : en
Pages : 56

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Excerpt from Spawning Areas and Abundance of Chinook Salmon (Oncorhynchus Tshawytscha) In the Columbia River Basin: Past and Present Spawn in intermediate and large tribu taries and in middle reaches of the main stem. Spring-run chinook salmon Spawn in some lower Columbia River tributaries such as the Willamette, Cowlitz, and Kalama Rivers. They also are distributed in middle tributaries of the Columbia and Snake Rivers. (fall-run chinook salmon, discussed later in the report, share spawning grounds in some sections of the Cowlitz and Kalama Rivers.) These are not all of the areas in which such duplications occur but are cited as examples. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.