The wave-drag hypothesis: an explanation for size-based lateral segregation during the upstream migration of salmonids

2004 ◽  
Vol 61 (1) ◽  
pp. 103-109 ◽  
Author(s):  
Nicholas F Hughes
Keyword(s):  
Sockeye Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Wave Drag ◽  
Upstream Migration ◽  
Large Fish ◽  
Drag Model ◽  
Migration Corridor ◽  
Migration Costs ◽  
Maximum Body ◽  
Lateral Segregation

During their spawning migration, large salmon, e.g., chinook (Oncorhynchus tshawytscha), swim upstream further from the bank than smaller ones, e.g., sockeye (Oncorhynchus nerka). This pattern is counterintuitive because natural selection should favor behavior that minimizes migration costs, yet by traveling further from the bank, large fish will have to swim against faster currents. Existing theory predicts that they will expend more energy than necessary as a result. One explanation for this apparently paradoxical behavior is that large fish swim further from the bank to avoid wave drag, the resistance associated with the generation of surface waves when swimming close to the surface. Wave drag was incorporated into existing theory, and the resulting model was tested to determine whether it explained size-based lateral segregation of chinook and sockeye salmon in the Nushagak River, Alaska. The wave-drag model accurately predicted the migration corridor for both species. Existing theory worked well for sockeye but not for chinook. The key to these predictions is that wave drag scales according the ratio of maximum body diameter to submergence depth, so bigger fish need to swim deeper to escape its effects.

Changes in Glycogen and Lactate Levels in Migrating Salmonid Fishes Ascending Experimental "Endless" Fishways

1964 ◽  
Vol 21 (2) ◽  
pp. 255-290 ◽  
Author(s):  
Anne R. Connor ◽  
Carl H. Elling ◽  
Edgar C. Black ◽  
Gerald B. Collins ◽  
Joseph R. Gauley ◽  
...  
Keyword(s):  
Muscle Glycogen ◽  
Sockeye Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Liver Glycogen ◽  
Individual Performance ◽  
Control Fish ◽  
Salmo Gairdneri ◽  
Upstream Migration ◽  
Salmonid Fishes ◽  
Muscle Lactate

Certain aspects of the performance and biochemistry of adult migrating salmonid fishes were investigated during ascents of 1:16- and 1:8-slope experimental fishways which employed locking devices permitting the simulation of fishways of any length. Fish tested were chinook salmon (Oncorhynchus tshawytscha), sockeye salmon (O. nerka) and steelhead trout (Salmo gairdneri) diverted from their upstream migration on the Columbia river at the Bonneville dam fishways during the summer of 1959. Blood and muscle lactate, and muscle and liver glycogen levels were determined in control fish, and in fish following three types of activity. Records of individual performance were kept.All species were willing to enter and capable of ascending fishways of either slope up to 1000 ft in height under favourable hydraulic conditions. Blood lactate and muscle glycogen determinations revealed the degree of exercise to be moderate even during prolonged ascents. Moderately high ascents (about 100 ft) in the steeper fishway apparently required the expenditure of some muscle glycogen whereas similar ascents in the 1:16 fishway did not. When muscle glycogen was utilized during prolonged ascents the expenditure appeared to be progressive. All species were apparently able to adapt to prolonged ascents of either fishway. Certain fish of each species tended to stop moving of their own volition in both fishways. After a 60-min volitional stop some evidence of recovery from the effects of exercise was observed. Discussion of the above data is presented.

An Acoustic Estimate of the Escapement of Sockeye Salmon (Oncorhynchus nerka) into Lake Washington in 1971

1974 ◽  
Vol 31 (2) ◽  
pp. 222-225 ◽  
Author(s):  
Richard E. Thorne ◽  
James J. Dawson
Keyword(s):  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Spawning Migration ◽  
Spawning Ground ◽  
Large Fish ◽  
Before And After ◽  
Lake Washington

The feasibility of estimating the escapement of sockeye salmon (Oncorhynchus nerka) into Lake Washington by hydroacoustics was explored during 1971. Surveys were made of large fish targets within the lake just before and after the spawning migration of sockeye salmon up the Cedar River. A decrease was observed after the spawning migration comparable to the estimated escapement as determined by weir counts and spawning ground surveys.

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

Selective predation by brown bears (Ursus arctos) foraging on spawning sockeye salmon (Oncorhynchus nerka)

2000 ◽  
Vol 78 (6) ◽  
pp. 974-981 ◽  
Author(s):  
Gregory T Ruggerone ◽  
Renn Hanson ◽  
Donald E Rogers
Keyword(s):  
Sockeye Salmon ◽  
Ursus Arctos ◽  
Oncorhynchus Nerka ◽  
The Body ◽  
Upstream Migration ◽  
Selective Predation ◽  
Bristol Bay ◽  
Brown Bears ◽  
Risk Of Predation ◽  
Salmon Population

Selective predation by and predation rates of brown bears (Ursus arctos) foraging on spawning sockeye salmon (Oncorhynchus nerka) in a small shallow creek in the Wood River lake system near Bristol Bay, Alaska, were quantified during 1986 and 1990–1992. Bears killed a high proportion of spawning salmon when few salmon entered the creek (92% of 505 fish) and a much smaller proportion when the spawning population reached a historical high (16% of 15 631 fish). Selective predation on salmon that differed in length, sex, and spawning condition was measured by tagging salmon at the mouth of the creek immediately prior to upstream migration and then recovering dead tagged fish during daily surveys of the entire creek. The relative frequencies of large, medium-sized, and small salmon killed by bears indicated that the risk of predation was more than 150% greater for large than for small salmon. A higher proportion of the male salmon population was killed and a greater proportion of male bodies were consumed than female salmon. Selectivity for male salmon increased as the spawning season progressed, possibly because male salmon weakened earlier and lived longer in a weakened state than female salmon. Male salmon were attacked mostly along the dorsal hump area, whereas female salmon tended to be attacked along the abdomen, where eggs could be exposed. Bears selectively killed female salmon prior to spawning during 1 of the 3 years, but only 6.1–7.8% of the female spawning populations were killed prior to spawning. These data support the hypothesis that selective predation by bears may influence the body morphology of spawning salmon.

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

1985 ◽  
Vol 42 (4) ◽  
pp. 693-700 ◽  
Author(s):  
Carl V. Burger ◽  
Richard L. Wilmot ◽  
David B. Wangaard
Keyword(s):  
Chinook Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Main Stem ◽  
Upstream Migration ◽  
Cook Inlet ◽  
Large Lakes ◽  
Spawning Areas ◽  
Winter Temperatures ◽  
Southcentral Alaska ◽  
Radio Transmitters

From 1979 to 1982,188 chinook salmon (Oncorhynchus tshawytscha) were tagged with radio transmitters to locate spawning areas in the glacial Kenai River, southcentral Alaska. Results confirmed that an early run entered the river in May and June and spawned in tributaries, and a late run entered the river from late June through August and spawned in the main stem. Spawning peaked during August in tributaries influenced by lakes, but during July in other tributaries. Lakes may have increased fall and winter temperatures of downstream waters, enabling successful reproduction for later spawning fish within these tributaries. This hypothesis assumes that hatching and emergence can be completed in a shorter time in lake-influenced waters. The time of upstream migration and spawning (mid- to late August) of the late run is unique among chinook stocks in Cook Inlet. This behavior may have developed only because two large lakes (Kenai and Skilak) directly influence the main-stem Kenai River. If run timing is genetically controlled, and if the various components of the two runs are isolated stocks that have adapted to predictable stream temperatures, there are implications for stock transplantation programs and for any activities of man that alter stream temperatures.

scholarly journals Modelling salmon migration as a mixture problem

2019 ◽  
Vol 76 (6) ◽  
pp. 856-870 ◽  
Author(s):  
Skip McKinnell
Keyword(s):  
Chinook Salmon ◽  
Sockeye Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Simulated Data ◽  
Columbia River ◽  
Single Pulse ◽  
Model Complexity ◽  
Fraser River ◽  
The Individual ◽  
Large Adult

Pulses of abundance in salmon migrations can arise from single populations arriving at different times, from multiple populations with different timing characteristics, or as a combination of these. Daily observations typically record an aggregate measure of abundance passing some location rather than the abundances of the individual components. An objective method is described that partitions a compound migration into its component parts by exploiting differences in the characteristics of each pulse. Simulated data were used to demonstrate when greater model complexity may be desirable. Three case studies of increasing complexity (Chilko Lake sockeye salmon smolts (Oncorhynchus nerka), large adult Columbia River Chinook salmon (Oncorhynchus tshawytscha), Fraser River salmon test fishery) demonstrate how the model can be applied in practice. Results indicated that Chilko Lake smolts rarely emigrate to sea as a single pulse, that the dates used to distinguish the spring run of Chinook salmon in the Columbia River may be overestimating its abundance, and that pulses of sockeye salmon abundance in a Fraser River ocean test fishery in 2014 may have arisen from some factor other than population composition.

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.

Effect of ACTH and Salmon Gonadotropin on Interrenal and Thyroid Activity of Gonadectomized Adult Sockeye Salmon (Oncorhynchus nerka)

1974 ◽  
Vol 31 (7) ◽  
pp. 1211-1214 ◽  
Author(s):  
Edward M. Donaldson ◽  
J. R. McBride
Keyword(s):  
Plasma Concentration ◽  
Chinook Salmon ◽  
Sockeye Salmon ◽  
Oncorhynchus Tshawytscha ◽  
Oncorhynchus Nerka ◽  
The Other ◽  
Thyroid Activity ◽  
Other Hand

Injection of a chinook salmon (Oncorhynchus tshawytscha) gonadotropin preparation into gonadectomized sockeye salmon (Oncorhynchus nerka) did not result in any increase in the plasma concentration of cortisol or cortisone, nor did it stimulate the activity of the interrenal tissue. On the other hand, injection of mammalian ACTH (Acthar) did result in an increase in the plasma concentration of cortisol and cortisone, and stimulated the interrenal tissue. The salmon gonadotropin preparation, however, elicited an increase in thyroid activity. The results suggest that in the salmon, ovulation is not caused by gonadotropin induced interrenal corticosteroidogenesis.

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.

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