Evaluation of side-aspect target strength and pulse width as potential hydroacoustic discriminators of fish species in rivers

1998 ◽  
Vol 55 (11) ◽  
pp. 2492-2502 ◽  
Author(s):  
Deborah L Burwen ◽  
Steven J Fleischman
Keyword(s):  
Statistical Models ◽  
Pulse Width ◽  
Sockeye Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Pacific Salmon ◽  
Discriminatory Power ◽  
Target Strength ◽  
Lateral Movement ◽  
As Species ◽  
Hydroacoustic Measurements

Split-beam hydroacoustic data were collected on 98 tethered and 10 unrestrained Pacific salmon of known size to evaluate side-aspect target strength and pulse width as species discriminators in rivers. Pulse width was better able to discriminate chinook (Oncorhynchus tshawytscha) from sockeye salmon (Oncorhynchus nerka) than target strength, although its discriminatory power may have arisen from differences in behavior as well as size between species. Standard deviation of -12 dB pulse width was the best univariate size predictor and species discriminator among tethered fish but performed poorly among unrestrained fish at close ranges; mean pulse width at -12 dB performed well among both. Discriminatory power of all variables declined as the number of echoes per fish was reduced. Fish orientation, lateral movement, and spatial position of the fish in the beam affected hydroacoustic measurements. As fish moved more from side to side, and as fish orientation departed from full side aspect, target strength declined monotonically but mean pulse width increased and then declined. We show how some of the confounding effects of fish behavior on hydroacoustic measurements can be removed using corrections based on statistical models.

Changes in the Average Size and Average Age of Pacific Salmon

1981 ◽  
Vol 38 (12) ◽  
pp. 1636-1656 ◽  
Author(s):  
W. E. Ricker
Keyword(s):  
Growth Rate ◽  
Chinook Salmon ◽  
Sockeye Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Gill Nets ◽  
Growing Seasons ◽  
Mean Size ◽  
Average Size

Of the five species of Pacific salmon in British Columbia, chinook salmon (Oncorhynchus tshawytscha) and coho salmon (O. kisutch) are harvested during their growing seasons, while pink salmon (O. gorbuscha), chum salmon (O. keta), and sockeye salmon (O. nerka) are taken only after practically all of their growth is completed. The size of the fish caught, of all species, has decreased, but to different degrees and over different time periods, and for the most part this results from a size decrease in the population. These decreases do not exhibit significant correlations with available ocean temperature or salinity series, except that for sockeye lower temperature is associated with larger size. Chinook salmon have decreased greatly in both size and age since the 1920s, most importantly because nonmaturing individuals are taken by the troll fishery; hence individuals that mature at older ages are harvested more intensively, which decreases the percentage of older ones available both directly and cumulatively because the spawners include an excess of younger fish. Other species have decreased in size principally since 1950, when the change to payment by the pound rather than by the piece made it profitable for the gill-netters to harvest more of the larger fish. Cohos and pinks exhibit the greatest decreases, these being almost entirely a cumulative genetic effect caused by commercial trolls and gill nets removing fish of larger than average size. However, cohos reared in the Strait of Georgia have not decreased in size, possibly because sport trolling has different selection characteristics or because of the increase in the hatchery-reared component of the catch. The mean size of chum and sockeye salmon caught has changed much less than that of the other species. Chums have the additional peculiarity that gill nets tend to take smaller individuals than seines do and that their mean age has increased, at least between 1957 and 1972. That overall mean size has nevertheless decreased somewhat may be related to the fact that younger-maturing individuals grow much faster than older-maturing ones; hence excess removal of the smaller younger fish tends to depress growth rate. Among sockeye the decrease in size has apparently been retarded by an increase in growth rate related to the gradual cooling of the ocean since 1940. However, selection has had two important effects: an increase in the percentage of age-3 "jacks" in some stocks, these being little harvested, and an increase in the difference in size between sockeye having three and four ocean growing seasons, respectively.Key words: Pacific salmon, age changes, size changes, fishery, environment, selection, heritability

Advances in Fish Tagging and Marking Technology

2012 ◽  
Keyword(s):  
Sockeye Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Pacific Salmon ◽  
Area Under The Curve ◽  
Dorsal Surface ◽  
Field Trials ◽  
Oncorhynchus Keta ◽  
Survey Costs ◽  
Tank Test ◽  
Auc Estimation

<i>Abstract</i>.—A micro-controlled fish tag which records post-tagging lifespan was developed, tested as a prototype, and then evaluated in field applications for measuring survey life. The method of constructing the Tilt-Tag and the results of tank test trials on Chinook salmon <i>Oncorhynchus tshawytscha</i>, preliminary field trials on chum salmon <i>Oncorhynchus keta </i>are reviewed, and full-scale field applications on sockeye salmon <i>Oncorhynchus nerka </i>are presented. Survey life (SL) is an essential component for area-under-the-curve (AUC) estimation of Pacific salmon <i>Oncorhynchus </i>spp. spawning escapements. However, direct estimates of SL are often unavailable because the estimates mostly require extensive and costly tag-recapture programs. In this study, the Tilt-Tag was used to estimate SL by measuring the elapsed time from tagging until the fish came to rest permanently on its lateral or dorsal surface. Tilt-Tag derived estimates of SL, combined with specification of survey rules that were based on historical run-timing and stream temperature, reduced survey costs by approximately 50% when compared to conventional tag-recapture methods. Abridged details on how to construct the Tilt-Tag are provided so that researchers will be able to make their own tags.

Changes in body size of Canadian Pacific salmon over six decades

2017 ◽  
Vol 74 (2) ◽  
pp. 191-201 ◽  
Author(s):  
Kyla M. Jeffrey ◽  
Isabelle M. Côté ◽  
James R. Irvine ◽  
John D. Reynolds
Keyword(s):  
Body Size ◽  
Sockeye Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Southern Oscillation ◽  
Rapid Change ◽  
Oncorhynchus Gorbuscha ◽  
Oncorhynchus Keta ◽  
Evolutionary Response

Body size can sometimes change rapidly as an evolutionary response to selection or as a phenotypic response to changes in environmental conditions. Here, we revisit a classic case of rapid change in body size of five species of Pacific salmon (Oncorhynchus spp.) caught in Canadian waters, with a six-decade analysis (1951–2012). Declines in size at maturity of up to 3 kg in Chinook (Oncorhynchus tshawytscha) and 1 kg in coho salmon (Oncorhynchus kisutch) during the 1950s and 1960s were later reversed to match or exceed earlier sizes. In contrast, there has been little change in sockeye salmon (Oncorhynchus nerka) sizes and initial declines in pink (Oncorhynchus gorbuscha) and chum salmon (Oncorhynchus keta) sizes have halted. Biomass of competing salmon species contributed to changes in size of all five species, and ocean conditions, as reflected by the North Pacific Gyre Oscillation and the Multivariate ENSO (El Niño – Southern Oscillation) indices, explained variation in four of the species. While we have identified a role of climate and density dependence in driving salmon body size, any additional influence of fisheries remains unclear.

scholarly journals Endangered wild salmon infected by newly discovered viruses

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Gideon J Mordecai ◽  
Kristina M Miller ◽  
Emiliano Di Cicco ◽  
Angela D Schulze ◽  
Karia H Kaukinen ◽  
...  
Keyword(s):  
Sockeye Salmon ◽  
Potential Role ◽  
Oncorhynchus Tshawytscha ◽  
Pacific Salmon ◽  
In Situ Hybridisation ◽  
Viral Disease ◽  
Wild Salmon ◽  
Fish Stocks ◽  
Farmed Salmon

The collapse of iconic, keystone populations of sockeye (Oncorhynchus nerka) and Chinook (Oncorhynchus tshawytscha) salmon in the Northeast Pacific is of great concern. It is thought that infectious disease may contribute to declines, but little is known about viruses endemic to Pacific salmon. Metatranscriptomic sequencing and surveillance of dead and moribund cultured Chinook salmon revealed a novel arenavirus, reovirus and nidovirus. Sequencing revealed two different arenavirus variants which each infect wild Chinook and sockeye salmon. In situ hybridisation localised arenavirus mostly to blood cells. Population surveys of >6000 wild juvenile Chinook and sockeye salmon showed divergent distributions of viruses, implying different epidemiological processes. The discovery in dead and dying farmed salmon of previously unrecognised viruses that are also widely distributed in wild salmon, emphasizes the potential role that viral disease may play in the population dynamics of wild fish stocks, and the threat that these viruses may pose to aquaculture.

scholarly journals Time-based signal characteristics as predictors of fish size and species for a side-looking hydroacoustic application in a river

2003 ◽  
Vol 60 (3) ◽  
pp. 662-668 ◽  
Author(s):  
Debby L Burwen ◽  
Steven J Fleischman ◽  
James D Miller ◽  
Mark E Jensen
Keyword(s):  
Species Composition ◽  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Target Strength ◽  
Lateral Movement ◽  
Echo Signal ◽  
Measurement Variability ◽  
Fish Size ◽  
Signal Characteristics ◽  
Better Than

Abstract Side-looking, fixed-location sonar is used to estimate the abundance of migrating chinook salmon Oncorhynchus tshawytscha in the Kenai River, Alaska. For this application, echo-envelope length has previously been shown to predict fish size better than target strength. Using tethered-fish experiments we generalize these findings to other hydroacoustic descriptors based on time measurements, including range-measurement variability and fish lateral movement. These variables are all descriptors of the echo signal through time. Measurements of these attributes were correlated with daily indices of the species composition of unrestrained fish passing the sonar site. We hypothesize that time-based characteristics are superior predictors of fish size because they capitalize on, or are robust to, the factors which compromise amplitude-based measurements with side-looking sonar.

MUSCLE PROTEINS OF PACIFIC SALMON (ONCORHYNCHUS): II. AN INVESTIGATION OF MUSCLE PROTEIN AND OTHER SUBSTANCES SOLUBLE IN SALT SOLUTIONS OF LOW IONIC STRENGTH BY COLUMN CHROMATOGRAPHY

1962 ◽  
Vol 40 (7) ◽  
pp. 919-927 ◽  
Author(s):  
H. Tsuyuki ◽  
E. Roberts ◽  
R. E. A. Gadd
Keyword(s):  
Sockeye Salmon ◽  
Moving Boundary ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
Muscle Protein ◽  
Deae Cellulose ◽  
Ophiodon Elongatus ◽  
The Pacific ◽  
Other Substances ◽  
Low Ionic Strength

The muscle myogens and other components of the spring salmon (O. tshawytscha), chum salmon (O. keta), coho salmon (O. kisutch), and sockeye salmon (O. nerka), as well as the lingcod (Ophiodon elongatus), were separated by the use of diethylaminoethyl (DEAE) cellulose columns. Significant amounts of slowly dialyzable inosine and inosinic acid which may lead to spurious peaks in moving-boundary electrophoretic separations have been shown to be present in the muscle myogen preparations. The basic differences in the muscle myogen components of the Pacific salmon and the lingcod are compared.

Mating success of alternative male phenotypes and evidence for frequency-dependent selection in Chinook salmon, Oncorhynchus tshawytscha

2010 ◽  
Vol 67 (12) ◽  
pp. 1933-1941 ◽  
Author(s):  
Barry A. Berejikian ◽  
Donald M. Van Doornik ◽  
Rob C. Endicott ◽  
Timothy L. Hoffnagle ◽  
Eugene P. Tezak ◽  
...  
Keyword(s):  
Mating Success ◽  
Oncorhynchus Tshawytscha ◽  
Pacific Salmon ◽  
Adult Males ◽  
Frequency Dependent ◽  
Frequency Dependent Selection ◽  
Male Density ◽  
The Family ◽  
Breeding Groups ◽  
One Year

As with other species, frequency-dependent selection during reproduction has long been proposed as an important mechanism in maintaining alternative male reproductive phenotypes in Pacific salmon ( Oncorhynchus spp.). Jack salmon mature one year earlier than the youngest females in a population and are much smaller than older “adult” males. We tested the hypothesis that mating success of both phenotypes is consistent with the frequency-dependent selection model. By holding male density constant and varying the frequency of adults and jacks in eight separate breeding groups, we found that adult male access to females, participation in spawning events, and adult-to-fry reproductive success increased with their decreasing frequency in a breeding group. Jacks exhibited the same pattern (increasing success with decreasing frequency), although the relationships were not as strong as for adults. Overall, jack and adult males mated with a similar number of females, but jacks sired only 20% of all offspring. Observational data suggested that adult males benefited from sperm precedence associated with their ability to court females and enter the nest first at the time of spawning. Our work provides the first experimental evidence of frequency-dependent selection during mating in the family Salmonidae.

scholarly journals Pacific salmon abundance trends and climate change

2011 ◽  
Vol 68 (6) ◽  
pp. 1122-1130 ◽  
Author(s):  
James R. Irvine ◽  
Masa-aki Fukuwaka
Keyword(s):  
Climate Change ◽  
Pacific Ocean ◽  
North Pacific ◽  
Sockeye Salmon ◽  
Coho Salmon ◽  
Pacific Salmon ◽  
North Pacific Ocean ◽  
Pink Salmon ◽  
The North ◽  
Abundance Trends

Abstract Irvine, J. R., and Fukuwaka, M. 2011. Pacific salmon abundance trends and climate change. – ICES Journal of Marine Science, 68: 1122–1130. Understanding reasons for historical patterns in salmon abundance could help anticipate future climate-related changes. Recent salmon abundance in the northern North Pacific Ocean, as indexed by commercial catches, has been among the highest on record, with no indication of decline; the 2009 catch was the highest to date. Although the North Pacific Ocean continues to produce large quantities of Pacific salmon, temporal abundance patterns vary among species and areas. Currently, pink and chum salmon are very abundant overall and Chinook and coho salmon are less abundant than they were previously, whereas sockeye salmon abundance varies among areas. Analyses confirm climate-related shifts in abundance, associated with reported ecosystem regime shifts in approximately 1947, 1977, and 1989. We found little evidence to support a major shift after 1989. From 1990, generally favourable climate-related marine conditions in the western North Pacific Ocean, as well as expanding hatchery operations and improving hatchery technologies, are increasing abundances of chum and pink salmon. In the eastern North Pacific Ocean, climate-related changes are apparently playing a role in increasing chum and pink salmon abundances and declining numbers of coho and Chinook salmon.

scholarly journals Sound-scattering spectra of steelhead (Oncorhynchus mykiss), coho (O. kisutch), and Chinook (O. tshawytscha) salmonids

2009 ◽  
Vol 66 (6) ◽  
pp. 1091-1099 ◽  
Author(s):  
Josiah S. Renfree ◽  
Sean A. Hayes ◽  
David A. Demer
Keyword(s):  
Oncorhynchus Mykiss ◽  
Oncorhynchus Tshawytscha ◽  
Target Identification ◽  
Target Strength ◽  
Sound Scattering ◽  
Broad Bandwidth ◽  
Sound Fields ◽  
Acoustic Methods ◽  
Measurement Tools ◽  
Scattering Spectra

Abstract Renfree, J. S., Hayes, S. A., and Demer, D. A. 2009. Sound-scattering spectra of steelhead (Oncorhynchus mykiss), coho (O. kisutch), and Chinook (O. tshawytscha) salmonids. – ICES Journal of Marine Science, 66: 1091–1099. A recently developed method for measuring total target strength (TTS) allows calculation of the absolute scattered energy from fish over a broad-bandwidth signal. This technique uses the ratio of coherent and incoherent sound fields reflected off fish swimming in tanks. In stark contrast to other acoustic methods, this technique works best in reverberant conditions, is self-calibrating, and conveniently provides measurements of sound-scattering spectra for possible target identification. It has been used to successfully characterize the scattering spectra of marine life such as anchovy, sardine, and krill. In this experiment, the broad-bandwidth scattering spectra are characterized for the salmonids steelhead (Oncorhynchus mykiss), coho (Oncorhynchus kisutch), and Chinook (Oncorhynchus tshawytscha). The TTS measurements demonstrate that the scattering spectra for these species are similar, yet discernible. These unique scattering spectra may provide means for acoustically identifying and enumerating such targets in rivers or streams. Having effective acoustic methods for assessing salmon abundance could become a major addition to currently available measurement tools and provide a new, low-impact assessment technique for both commercial and endangered populations.

The Ecology of Juvenile Salmon in the Northeast Pacific Ocean: Regional Comparisons

2007 ◽  
Keyword(s):  
Chinook Salmon ◽  
Sockeye Salmon ◽  
Pacific Salmon ◽  
Gulf Of Alaska ◽  
Juvenile Salmon ◽  
Stomach Fullness ◽  
Feeding Intensity ◽  
Percentage Weight ◽  
Juvenile Pacific Salmon ◽  
Survival Patterns

Abstract.—Upon entering marine waters, juvenile Pacific salmon <em>Oncorhynchus </em>spp. depend on feeding at high and sustained levels to achieve growth necessary for survival. In the last decade, several concurrent studies have been examining the food habits and feeding intensity of juvenile Pacific salmon in the shelf regions from California to the northern Gulf of Alaska. In this paper, we compared results from feeding studies for all five species of juvenile salmon (Chinook salmon <em>O. tshawytscha</em>, coho salmon <em>O. kisutch</em>, chum salmon <em>O. keta, </em>sockeye salmon <em>O. nerka</em>, and pink salmon <em>O. gorbuscha</em>) between 2000 and 2002, years when these regions were sampled extensively. Within these years, we temporally stratified our samples to include early (May–July) and late (August–October) periods of ocean migration. Coho and Chinook salmon diets were most similar due to a high consumption of fish prey, whereas pink, chum, and sockeye salmon diets were more variable with no consistently dominant prey taxa. Salmon diets varied more spatially (by oceanographic and regional factors) than temporally (by season or year) in terms of percentage weight or volume of major prey categories. We also examined regional variations in feeding intensity based on stomach fullness (expressed as percent body weight) and percent of empty or overly full stomachs. Stomach fullness tended to be greater off Alaska than off the west coast of the United States, but the data were highly variable. Results from these comparisons provide a large-scale picture of juvenile salmon feeding in coastal waters throughout much of their range, allowing for comparison with available prey resources, growth, and survival patterns associated with the different regions.

Sign in / Sign up

Export Citation Format

Share Document