Differences in otolith microstructure between hatchery-reared and wild Chinook salmon (Oncorhynchus tshawytscha)

1995 ◽  
Vol 52 (2) ◽  
pp. 344-352 ◽  
Author(s):  
Z. Zhang ◽  
R. J. Beamish ◽  
B. E. Riddell
Keyword(s):  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Otolith Microstructure ◽  
Exogenous Feeding ◽  
Daily Growth ◽  
Strait Of Georgia ◽  
Growth Increments

Otolith microstructure exhibited some characteristic differences between hatchery-reared and wild chinook salmon (Oncorhynchus tshawytscha) from the Cowichan River. Daily growth increments that formed in the otoliths of the hatchery-reared chinook salmon after exogenous feeding were more regular in width and contrast than those in the otoliths of wild chinook salmon. In addition, otoliths from hatchery-reared individuals frequently produced a check when the fish were released from the hatchery. Eighty-nine percent of a sample of 67 chinook smolts that had been coded-wire tagged in hatcheries and later captured in the Strait of Georgia were correctly identified as originating from hatcheries based on otolith microstructure. These tagged fish originated from at least 17 different hatcheries, indicating that the method could be used to identify chinook salmon originating from other hatcheries.

scholarly journals Identifying the contribution of wild and hatchery Chinook salmon (Oncorhynchus tshawytscha) to the ocean fishery using otolith microstructure as natural tags

2007 ◽  
Vol 64 (12) ◽  
pp. 1683-1692 ◽  
Author(s):  
Rachel Barnett-Johnson ◽  
Churchill B Grimes ◽  
Chantell F Royer ◽  
Christopher J Donohoe
Keyword(s):  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Wild Fish ◽  
Otolith Microstructure ◽  
Exogenous Feeding ◽  
Daily Growth ◽  
Wild Salmon ◽  
Growth Increments ◽  
In The Wild ◽  
Mixed Stock

Quantifying the contribution of wild (naturally spawned) and hatchery Chinook salmon (Oncorhynchus tshawytscha) to the mixed-stock ocean fishery is critical to understanding their relative importance to the persistence of salmon stocks. The inability to distinguish hatchery and wild salmon has inhibited the detection of declines or recoveries for many wild populations. By using Chinook salmon of known hatchery and wild origin, we established a baseline for separating these two sources using otolith microstructure. Otoliths of wild salmon contained a distinct exogenous feeding check likely reflecting an abrupt transition in food resources from maternal yolk not experienced by fish reared in hatcheries. Daily growth increments in otoliths from hatchery salmon immediately after the onset of exogenous feeding were wider and more uniform in width than those in wild fish. The discriminant function that we used to distinguish individuals reared in hatcheries or in the wild was robust between years (1999 and 2002), life history stages (juveniles and adults), and geographic regions (California, British Columbia, and Alaska) and classified fish with ~91% accuracy. Results from our mixed-stock model estimated that the contribution of wild fish was 10% ± 6%, indicating hatchery supplementation may be playing a larger role in supporting the central California coastal fishery than previously assumed.

Effects of pH on the early development and growth and otolith microstructure of chinook salmon, Oncorhynchus tshawytscha

1985 ◽  
Vol 63 (1) ◽  
pp. 22-27 ◽  
Author(s):  
G. H. Geen ◽  
J. D. Neilson ◽  
M. Bradford
Keyword(s):  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Growth Increment ◽  
Low Ph ◽  
Acidic Water ◽  
Daily Growth ◽  
Stage Of Development ◽  
Growth Increments ◽  
Effects Of Ph ◽  
Daily Growth Increment

Chinook salmon (Oncorhynchus tshawytscha) eggs, alevins, and fry were reared in pH 4.5, 5.0. 5.5, 6.2 (control), and 7.0 water from the eyed stage of development. Survival through hatching was >90% in all instances. Alevin mortality was high at pH 4.5 and 5.0. Fry were more tolerant of low pH than alevins. Growth rates of alevins and fry held at or above pH 5.0 and 4.5, respectively, were not affected by pH, nor did exposure to acidic water retard otolith development or result in their resorption. One otolith daily growth increment was formed every 24 h in alevins and fry irrespective of pH. Widths of otolith daily growth increments decreased when fry were transferred to pH 4.5 water and increased on their return to higher pH indicating changes in growth rate. Transfer of fry from pH 6.2 to pH 5.0 or 5.5 had no effect on increment widths.

Otoliths of Chinook Salmon (Oncorhynchus tshawytscha): Daily Growth Increments and Factors Influencing Their Production

1982 ◽  
Vol 39 (10) ◽  
pp. 1340-1347 ◽  
Author(s):  
John D. Neilson ◽  
Glen H. Geen
Keyword(s):  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Fish Length ◽  
Feeding Frequency ◽  
Otolith Growth ◽  
Increment Width ◽  
Daily Growth ◽  
Factors Affecting ◽  
Growth Increments ◽  
Otolith Increment

The effects of photoperiod, feeding frequency, and water temperature on formation of otolith daily growth increments in juvenile chinook salmon (Oncorhynchus tshawytscha) were examined. Feeding frequency influenced both increment number and width, whereas photoperiod and temperature affected only increment width. Fish fed once/24 h produced one increment every 24 h on average, while fish fed 4 times/24 h produced more than one increment every 24 h. Wider increments were produced in fish exposed to warmer water (11 °C) or 24 h of darkness. The ratio of otolith size to fish size remained constant throughout and between the photoperiod, temperature, and feeding frequency experiments, regardless of the number or width of increments produced. Although otolith growth is isometric with respect to increase in fish length under these experimental regimes, otolith microstructure will differ in fish of the same size reared under different environmental conditions. An understanding of factors affecting otolith increment production is required before increment number and width can be used to assess growth rates.Key words: otolith, daily, growth increments, chinook salmon

scholarly journals Chinook salmon exhibit long-term rearing and early marine growth in the Fraser River, B.C., a large urban estuary

2020 ◽  
Author(s):  
Lia Chalifour ◽  
David C Scott ◽  
Misty MacDuffee ◽  
Steven Stark ◽  
John F Dower ◽  
...  
Keyword(s):  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Pacific Salmon ◽  
Genetic Stock ◽  
Daily Growth ◽  
Estuarine Habitat ◽  
Salmon River ◽  
Salmon Population ◽  
Brackish Marshes ◽  
Saline Habitats

Estuaries represent a transition zone for salmon migrating from freshwater to marine waters, yet their contribution to juvenile growth is poorly quantified. Here, we use genetic stock identification and otolith analyses to quantify estuarine habitat use by Chinook salmon (<i>Oncorhynchus tshawytscha</i>) – the Pacific salmon species considered most reliant on this habitat – in Canada’s most productive salmon river, the Fraser. Two years of sampling revealed subyearling migrant (“ocean-type”) Chinook from the Harrison River to be the estuary’s dominant salmon population throughout the emigration period. These Chinook salmon were caught predominantly in the estuary’s brackish marshes but shifted to more saline habitats as they grew. Otolith analyses indicated that these Chinook salmon have wide-ranging entry timing (from February to May), and longer estuarine residency (weeks to months, mean 41.8 days) than estimated by prior studies, but similar daily growth rates (mean 0.57 mm +/- 0.13 SD) across entry dates and residency periods, implying sufficient foraging opportunities throughout the emigration period and habitats. Together, these results suggest that estuarine habitat is more important for early marine growth of subyearling migrant Chinook salmon than previously recognized.

Chinook salmon (Oncorhynchus tshawytscha) density, growth, mortality, and movement in two Lake Michigan tributaries

1984 ◽  
Vol 62 (1) ◽  
pp. 65-71 ◽  
Author(s):  
L. M. Carl
Keyword(s):  
Chinook Salmon ◽  
Lake Michigan ◽  
Oncorhynchus Tshawytscha ◽  
Initial Density ◽  
Mortality Rates ◽  
Daily Growth ◽  
Daily Rate ◽  
Pine Creek ◽  
Mortality Estimates ◽  
Overall Mortality

Spawning density and the time of spawning (October) were similar in two tributaries of Lake Michigan in 1977 and 1978. Drift of recently emerged fry began in April and continued into June. During 1977–1979, the density of chinook salmon juveniles increased rapidly in early May to 0.3–2.9 fish/m2 and then declined to 0.2–0.8 fish/m2 by late June when most of the fish smolted. Instantaneous mortality estimates were variable between years and sites in both creeks, but overall mortality was similar in both streams with an average daily rate of 0.024 for Baldwin Creek and 0.025 for Pine Creek. A regression of the mortality rates versus initial density indicated the mortality rates were dependent on the initial fry density. There was no correlation between an index of spawner density and the number of smolts produced. No correlation was found between initial resident fry density and emergent fry colonization. Size-selective mortality was indicated in some stream sections. The daily growth rates for fish in both streams varied between 0.28 and 1.01 mm per day. These rates were similar to or higher than rates reported in the literature from other stocks of chinook salmon on the west coast of North America and Lake Ontario.

scholarly journals Low-Lipid Diets Fed at Reduced Ration: Effects on Growth, Body Composition, and Survival of Juvenile Chinook Salmon

2019 ◽  
Vol 10 (2) ◽  
pp. 500-508
Author(s):  
Karen M. Cogliati ◽  
Julia R. Unrein ◽  
Wendy M. Sealey ◽  
Frederic T. Barrows ◽  
Olivia Hakanson ◽  
...  
Keyword(s):  
Body Composition ◽  
Lipid Content ◽  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Whole Body ◽  
Body Lipid ◽  
Daily Growth ◽  
Commercial Diet ◽  
High Lipid ◽  
Lipid Diet

Abstract There is a growing demand within research and conservation hatcheries to rear fish that more closely approximate the smaller size and leaner body composition of their wild counterparts. Low-lipid diets may help achieve this goal as they can provide all the nutritional needs of young fish and can lead to slower growth and leaner bodies. We compared growth of Chinook Salmon Oncorhynchus tshawytscha fed three experimental low-lipid diets (11–12, 8–9, 4–6% lipid) at the onset of feeding with a commercially available high-lipid diet (18–20%) and an experimentally formulated high-lipid control (13.9% lipid). After 5 mo on their respective treatments, the size, growth rate, and daily growth index of fish on the commercial diet were significantly higher than those on the three low-lipid diets. We also compared whole-body lipid content across our five diet treatments. Whole-body lipid content was significantly different across the five diets, with fish fed the commercial diet having, on average, an almost twofold higher lipid content over fish fed the lowest lipid diet formulation. We present comparable data from a limited sample of wild juvenile conspecifics as observations. We suggest that low-lipid starter diets can be used to produce healthy fish that more likely emulate some of the variations in size and body composition of wild fish.

A probabilistic analysis of decision-making about trip duration by Strait of Georgia sport anglers

1999 ◽  
Vol 56 (6) ◽  
pp. 960-972 ◽  
Author(s):  
Barry D Smith
Keyword(s):  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Access Point ◽  
Strait Of Georgia ◽  
Sport Fishery ◽  
Likelihood Model ◽  
Catch Rates ◽  
Autumn And Winter

Since 1984, an access-point creel survey of the Strait of Georgia, British Columbia, sport fishery has generated data on catch, effort, and attributes of effort from thousands of interviews of salmon anglers completing a daily boat-trip. I present a maximum-likelihood model for this daily bag limit (DBL) constrained fishery that estimates catch rate and variance for various angling fleets (as defined by boat-trip attributes such as the number of angling lines), estimates the probability that a boat-trip ends after a certain number of hours angling, and measures how angling success influences that probability. Most anglers targeting either chinook salmon (Oncorhynchus tshawytscha) or coho salmon (Oncorhynchus kisutch) became more likely to end a boat-trip in response to angling success, i.e., they were satiated by angling success before reaching a DBL. However, autumn and winter chinook salmon anglers tended to extend a boat-trip in response to angling success, i.e., they were motivated by angling success. Variability in angling success could not be attributed to variability in angler skill. Coho salmon catch rates increased by about 42% with each additional angling line per boat-trip up to three. The model can be used to judge the effectiveness of a DBL in reducing daily catch.

Estuarine Growth of Juvenile Chinook Salmon (Oncorhynchus tshawytscha) as Inferred from Otolith Microstructure

1985 ◽  
Vol 42 (5) ◽  
pp. 899-908 ◽  
Author(s):  
John D. Neilson ◽  
Glen H. Geen ◽  
Daniel Bottom
Keyword(s):  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
River Estuary ◽  
Otolith Microstructure ◽  
Limited Growth ◽  
Juvenile Chinook Salmon ◽  
Otolith Increments ◽  
Juvenile Chinook ◽  
Elevated Water ◽  
Conversion Efficiencies

The growth of juvenile chinook salmon (Oncorhynchus tshawytscha) in the Sixes River Estuary, Oregon, was inferred from otolith microstructure. Otolith increments appeared to be formed daily, on average, and a transition between those produced during freshwater residence and estuary residence was apparent. Otolith microstructure was also examined with respect to time series of water temperature, population density, and benthic standing crop data. While the results supported the hypothesis of food-limited growth, elevated water temperatures in midsummer may have decreased food conversion efficiencies, thus also contributing to an observed growth rate decline. It was also found that from counts of otolith increments formed during freshwater life, fish that hatched relatively late tended to spend less time in freshwater before moving downstream to the estuary.

Systematic hexamitid (Protozoa: Diplomonadida) Infection in seawater pen-reared Chinook salmon Oncorhynchus tshawytscha

1992 ◽  
Vol 14 ◽  
pp. 81-89 ◽  
Author(s):  
ML Kent ◽  
J Ellis ◽  
JW Fournie ◽  
SC Dawe ◽  
JW Bagshaw ◽  
...  
Keyword(s):  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha
Sign in / Sign up

Export Citation Format

Share Document