A Bioenergetics Analysis of Diel Vertical Migration by Kokanee Salmon, Oncorhynchus nerka

Diel vertical migration of fishes is probably a result of the combined effects of several selective forces, including predator avoidance, foraging efficiency, and bioenergetic efficiency. We considered both foraging efficiency and energetic efficiency as a combined effect which we called growth maximization. The importance of growth maximization as a selective force was evaluated with a bioenergetics-based model to estimate growth rates of various migration scenarios of kokanee salmon, Oncorhynchus nerka. Environmental parameters (temperature and zooplankton distributions) in the model were obtained from a North Carolina reservoir with an established population of kokanee. The simulations demonstrated that vertical migrations can be energetically advantageous when kokanee and their prey are thermally segregated and that ontogenetic and seasonal differences in the optimal migration strategy should be expected. The general rule for vertical migration as determined from the simulations is to feed where net energy intake is maximized and then reside when not feeding where energetic costs are minimized and food is digested to the point that consumption during the next feeding period is not limited by the amount of undigested food remaining in the stomach. Data obtained from vertical gill nets and hydroacoustics were compared with model predictions.

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Diel vertical migration of adult burbot: a dynamic trade-off among feeding opportunity, predation avoidance, and bioenergetic gain

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2013-0183 ◽

2013 ◽

Vol 70 (12) ◽

pp. 1765-1774 ◽

Cited By ~ 25

Author(s):

P.M. Harrison ◽

L.F.G. Gutowsky ◽

E.G. Martins ◽

D.A. Patterson ◽

A. Leake ◽

...

Keyword(s):

Vertical Migration ◽

Diel Vertical Migration ◽

Depth Distribution ◽

Benthic Species ◽

Migration Strategy ◽

Trade Off ◽

Vertical Activity ◽

Benthic Fishes ◽

Diel Period ◽

Migration Probability

Diel vertical migration (DVM) of pelagic organisms is typically attributed to bioenergetic gain, foraging opportunity, predator avoidance, and multifactor hypotheses. While a number of benthic species perform nightly migrations into shallower waters, the function of these DVMs has largely been ignored in benthic fishes. We used depth and temperature sensing telemetry to investigate DVM function in burbot (Lota lota), a freshwater benthic piscivore. We modeled the influence of season, diel period, and body size on the depth, vertical activity, migration probability, and thermal experience of 47 adult burbot over 2 years in a reservoir in British Columbia, Canada. Burbot were found to occupy significantly shallower water at night than during the day. Our results, which showed elevated nightly activity and a seasonal size-structured depth distribution during DVMs, suggest these migrations likely provide a feeding opportunity “window” for this nocturnal predator, constrained by predation or cannibalism threats to smaller individuals. The observed thermal experience patterns suggest DVM may also provide a seasonal bioenergetic advantage. Our detection of within-individual plasticity in migration strategy is indicative of a partial migration. Taken together, our results suggest a multifactor DVM hypothesis: a dynamic trade-off among bioenergetic advantage, foraging opportunity, and predation threat.

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Acoustic Analysis of Diel Vertical Migration Behavior of Mysis relicta and Kokanee (Oncorhynchus nerka) within Okanagan Lake, British Columbia

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f91-010 ◽

1991 ◽

Vol 48 (1) ◽

pp. 67-72 ◽

Cited By ~ 35

Author(s):

David A. Levy

Keyword(s):

Water Column ◽

Vertical Migration ◽

Diel Vertical Migration ◽

Acoustic Analysis ◽

Oncorhynchus Nerka ◽

Target Strength ◽

Migration Behavior ◽

Mysis Relicta ◽

Dual Beam ◽

Diel Vertical Migrations

Dual-beam acoustic surveys of Okanagan Lake suggested active diel vertical migrations of Mysis relicta and kokanee (Oncorhynchus nerka) within the pelagic zone. Mysis relicta were situated between 90–150 m during the day and migrated upwards into the thermocline region of the water column at night. Two groups of kokanee targets were detected. The first undertook a diel vertical migration and coalesced at dusk with a second, shallow-oriented group of targets. Daytime target strength estimates taken while the two groups were vertically segregated in the water column suggested an 8–12 db lower target strength of the deeper group. The results provide acoustic evidence for a smaller body size in the deeper group and the occurrence of an ontogenetic shift in diel migratory behavior of kokanee within Okanagan Lake. Diel comparisons of depth distribution suggested spatial segregation of Mysis and kokanee over much of the diel cycle.

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Field evaluation of a bioenergetics-based foraging model for kokanee (Oncorhynchus nerka)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f99-218 ◽

1999 ◽

Vol 56 (S1) ◽

pp. 140-151 ◽

Cited By ~ 29

Author(s):

Jason D Stockwell ◽

Brett M Johnson

Keyword(s):

Surface Waters ◽

Vertical Migration ◽

Diel Vertical Migration ◽

Lake Trout ◽

Oncorhynchus Nerka ◽

Field Evaluation ◽

Relative Importance ◽

Daily Growth ◽

Thermal Habitat ◽

Foraging Constraints

We used a bioenergetics-based foraging model to determine if bioenergetic and foraging constraints could explain kokanee (Oncorhynchus nerka) diel vertical migration in Blue Mesa Reservoir, Colorado. We compared model predictions of daily growth and migration strategies with observed growth and diel vertical distributions on three dates during the summer. Results suggest that bioenergetic and foraging constraints were not sufficient to explain diel vertical migration early in the summer, when thermal stratification was weak. However, these constraints could explain observed patterns later in the summer, when optimal thermal habitat for kokanee was spatially segregated from food-rich surface waters. The onset of a strong thermocline, and its exclusion of piscivorous lake trout (Salvelinus namaycush) from surface waters, appeared to determine the relative importance of predation risk for kokanee diel vertical migration patterns. Our observations and modeling results suggest that the relative importance of various factors driving diel vertical migration changes seasonally. Furthermore, the relative importance of each factor likely varies from system to system and may have caused the variety of single-factor hypotheses proposed to explain kokanee diel vertical migration. The model provides a framework for studying diel vertical migration across systems of differing thermal regimes, productivity, and predation pressures.

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Seasonal variation in temperature preference of juvenile Atlantic cod (Gadus morhua), with evidence supporting an energetic basis for their diel vertical migration

Canadian Journal of Zoology ◽

10.1139/z91-183 ◽

1991 ◽

Vol 69 (5) ◽

pp. 1302-1307 ◽

Cited By ~ 47

Author(s):

Donald S. Clark ◽

John M. Green

Keyword(s):

Seasonal Variation ◽

Vertical Migration ◽

Diel Vertical Migration ◽

Gadus Morhua ◽

Atlantic Cod ◽

Energetic Efficiency ◽

Temperature Preference ◽

Ambient Temperatures ◽

Inshore Waters ◽

Conception Bay

Juvenile (3-year-old) Atlantic cod (Gadus morhua) from Broad Cove, Conception Bay, Newfoundland, exhibit seasonal variation in temperature preference. Laboratory studies show that juvenile cod from ambient temperature water prefer temperatures that correlate closely with seasonal changes in the temperature of the inshore waters that they inhabit. A similar pattern is shown by fish held in 10 °C water over winter, indicating that variation in temperature preference is not simply a response to changing ambient temperatures but occurs in an anticipatory manner that allows them to maintain their physiologically optimal temperature at a seasonally appropriate level. The results also support the hypothesis that the diel vertical migration of juvenile cod in summer increases energetic efficiency by reducing metabolic costs in nonfeeding hours.

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