The influence of food availability, predation risk, and metabolic costs on the evolutionary stability of diel vertical migration in zooplankton

An optimisation model was developed to examine the effect of predation risk and environmental conditions on the diel vertical migration (DVM) of adult northern krill (Meganyctiphanes norvegica). Model predictions were compared in two locations with contrasting environmental conditions, the Clyde Sea and the Kattegat. The model was constructed from a combination of parameterised functions and empirical field data obtained during summer conditions. Parameter matrices were set up to cover the entire water column over a 24-h period. The first matrix contained values for "net energy gain," which incorporated empirical data on temperature-dependent respiration, copepod and phytoplankton abundance, and a functional response model for feeding rate. The second matrix expressed the risk of encountering a generalised visual (fish) predator as a function of light levels. The optimisation procedure sought a path through depth and time such that the energy gain was equal to the amount necessary to grow, produce eggs, and moult, while the risk of predation was minimised. The model predicted DVM in both the Clyde Sea and the Kattegat. Sensitivity analyses showed that the predicted DVM pattern was mainly driven by food and predation risk, with temperature effects on metabolic costs having a minor effect.

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Influence of food availability, predation risk and initial body size on growth and maturation of Cloeon dipterum (Ephemeroptera: Baetidae)

Zoosymposia ◽

10.11646/zoosymposia.11.1.9 ◽

2016 ◽

Vol 11 ◽

pp. 53-64 ◽

Cited By ~ 2

Author(s):

JAN ŠUPINA ◽

JINDŘIŠKA BOJKOVÁ ◽

DAVID S. BOUKAL

Keyword(s):

Growth Rate ◽

Life History ◽

Body Size ◽

Predation Risk ◽

Food Availability ◽

Larval Mortality ◽

Food Limitation ◽

Larval Growth ◽

Influence Of Food ◽

Cloeon Dipterum

Larval growth and maturation in aquatic insects are phenotypically plastic and can change in response to the amount and quality of resources, or under predation risk. While better food conditions typically lead to faster growth and earlier maturation at larger body size and hence higher fecundity, the effects of predation risk can vary depending on its strength and selectivity with respect to size or stage. Studies on lotic mayflies (Ephemeroptera) have reported two direct and two indirect life history responses to increased predation risk: slower growth rate and later maturation at the same or smaller size, and faster or unaltered growth rate and earlier maturation at smaller body size. However, life history responses of standing water mayflies to predation risk are unknown. To fill this gap, we carried out a full-factorial laboratory experiment to study the influence of food availability (full/reduced) and predation risk (present/absent predator cues) by dragonfly larvae on growth and maturation of larvae of the lentic mayfly Cloeon dipterum. Males and females responded similarly to food limitation and predation risk. Predation risk had no effect on maturation size, larval mortality and metamorphic failure. However, growth rate, number of moults and development time were all affected by predation risk, and its net effect was modified by food availability and initial body size of the larvae. These results suggest that life history responses to suboptimal conditions depend on body size at the onset of such conditions. Finally, a small group of larvae grew at much slower rates and developed much longer than other individuals of similar initial size, possibly due to bet-hedging or inclusion of multiple genotypes in the experiment.

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Diel vertical migration behaviour in Euphausiids of the northern Benguela current: seasonal adaptations to food availability and strong gradients of temperature and oxygen

Journal of Plankton Research ◽

10.1093/plankt/fbt030 ◽

2013 ◽

Vol 35 (4) ◽

pp. 792-812 ◽

Cited By ~ 19

Author(s):

Thorsten Werner ◽

Friedrich Buchholz

Keyword(s):

Food Availability ◽

Vertical Migration ◽

Diel Vertical Migration ◽

Seasonal Adaptations ◽

Migration Behaviour ◽

Benguela Current

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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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