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

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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Vertical distribution of Baltic sprat larvae: changes in patterns of diel migration?

ICES Journal of Marine Science ◽

10.1093/icesjms/fsm068 ◽

2007 ◽

Vol 64 (5) ◽

pp. 956-962 ◽

Cited By ~ 20

Author(s):

Rüdiger Voss ◽

Jörn O. Schmidt ◽

Dietrich Schnack

Keyword(s):

Vertical Distribution ◽

Surface Waters ◽

Vertical Migration ◽

Diel Vertical Migration ◽

Behavioural Change ◽

Migration Patterns ◽

Near Surface ◽

Diel Migration ◽

The Baltic ◽

Comparison Of The Results

Abstract Voss, R., Schmidt, J. O., and Schnack, D. 2007. Vertical distribution of Baltic sprat larvae: changes in patterns of diel migration? – ICES Journal of Marine Science, 64: 956–962. Ontogenetic and diurnal vertical migration patterns of Baltic sprat larvae were investigated for the periods 1989–1990 and 1998–2002. Comparison of the results led to the hypothesis that the diel vertical migration behaviour of sprat larvae >10 mm has changed. In 1989 and 1990, sprat larvae migrated to the surface at night, whereas they stayed 30–50 m deep by day. From 1998 to 2002, sprat larvae showed no signs of diel vertical migration, remaining in warmer, near-surface water by day and night. This behavioural change coincided with a more general change in the Baltic ecosystem, i.e. an increase in near-surface temperature and a general increase in abundance of the major prey organism (Acartia spp.) of Baltic sprat larvae, with more pronounced aggregation in surface waters.

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

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f93-258 ◽

1993 ◽

Vol 50 (11) ◽

pp. 2336-2349 ◽

Cited By ~ 75

Author(s):

Mark S. Bevelhimer ◽

S. Marshall Adams

Keyword(s):

Vertical Migration ◽

Diel Vertical Migration ◽

Oncorhynchus Nerka ◽

General Rule ◽

Foraging Efficiency ◽

Energetic Efficiency ◽

Net Energy ◽

Migration Strategy ◽

Kokanee Salmon ◽

Growth Maximization

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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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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Larval Diel Vertical Migration of the Marine GastropodKelletia kelletii(Forbes, 1850)

Journal of Marine Biology ◽

10.1155/2012/386575 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 6

Author(s):

Melissa R. Romero ◽

Kimberly M. Walker ◽

Carmen J. Cortez ◽

Yareli Sanchez ◽

Kimberly J. Nelson ◽

...

Keyword(s):

Surface Waters ◽

Vertical Migration ◽

Larval Dispersal ◽

Diel Vertical Migration ◽

Population Connectivity ◽

Column Height ◽

Night Time ◽

Laboratory Culturing ◽

Vertical Positioning ◽

Fishery Species

Documenting larval behavior is critical for building an understanding of larval dispersal dynamics and resultant population connectivity. Nocturnal diel vertical migration (DVM), a daily migration towards the surface of the water column at night and downward during the day, can profoundly influence dispersal outcomes. Via laboratory experiments we investigated whether marine gastropodKelletia kelletiilarvae undergo nocturnal DVM and whether the behavior was influenced by the presence of light, ontogeny, and laboratory culturing column height. Larvae exhibited a daily migration pattern consistent with nocturnal diel vertical migration with lower average vertical positioning (ZCM) during day-time hours and higher vertical positioning at night-time hours. ZCM patterns varied throughout ontogeny; larvae became more demersal as they approached competency. There was no effect of column height on larval ZCM. DVM behavior persisted in the absence of light, indicating a possible endogenous rhythm. Findings from field plankton tows corroborated laboratory nocturnal DVM findings; significantly moreK.kelletiiwere found in surface waters at midnight compared to at noon. Unraveling the timing of and the cues initiating DVM behavior inK.kelletiilarvae can help build predictive models of dispersal outcomes for this emerging fishery species.

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Diel vertical migration in the Lake Superior pelagic community. II. Modeling trade-offs at an intermediate trophic level

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f06-125 ◽

2006 ◽

Vol 63 (10) ◽

pp. 2296-2307 ◽

Cited By ~ 58

Author(s):

Olaf P Jensen ◽

Thomas R Hrabik ◽

Steven J.D. Martell ◽

Carl J Walters ◽

James F Kitchell

Keyword(s):

Predation Risk ◽

Trophic Level ◽

Vertical Migration ◽

Diel Vertical Migration ◽

Lake Trout ◽

Lake Superior ◽

High Growth ◽

Growth Trajectory ◽

Mysis Relicta ◽

Trade Offs

Several hypotheses have been proposed to explain diel vertical migration (DVM); however, they have generally been applied to DVM behavior of a single trophic level. We evaluate the costs (predation risk) and benefits (foraging rate and growth rate potential) of different hypothetical and observed DVM trajectories for a three-level pelagic food chain in Lake Superior containing opossum shrimp (Mysis relicta), deepwater ciscoes (Coregonus spp.), and lake trout (Salvelinus namaycush). Lake trout appear to be maximizing foraging and growth rates by tracking vertically migrating ciscoes, while the DVM trajectories of ciscoes suggests a trade-off between predation risk and growth. For ciscoes, two alternative DVM trajectories both minimize the ratio of risk to growth: a shallow trajectory that follows low light levels down to 80 m during the day and a deep trajectory (below 150 m) that tracks highest Mysis densities. Observed cisco DVM trajectories appear to follow the shallow high risk – high growth trajectory in 2001, but switch to the deep, low risk – low growth trajectory in 2004 when lake trout density was higher and the density of ciscoes was lower.

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