Body length-dependent diel vertical migration of Antarctic krill in relation to food availability and predator avoidance in winter at South Georgia

Abstract Antarctic krill (Euphausia superba) are high latitude pelagic organisms which play a key ecological role in the ecosystem of the Southern Ocean. To synchronize their daily and seasonal life-traits with their highly rhythmic environment, krill rely on the implementation of rhythmic strategies which might be regulated by a circadian clock. A recent analysis of krill circadian transcriptome revealed that their clock might be characterized by an endogenous free-running period of about 12–15 h. Using krill exposed to simulated light/dark cycles (LD) and constant darkness (DD), we investigated the circadian regulation of krill diel vertical migration (DVM) and oxygen consumption, together with daily patterns of clock gene expression in brain and eyestalk tissue. In LD, we found clear 24 h rhythms of DVM and oxygen consumption, suggesting a synchronization with photoperiod. In DD, the DVM rhythm shifted to a 12 h period, while the peak of oxygen consumption displayed a temporal advance during the subjective light phase. This suggested that in free-running conditions the periodicity of these clock-regulated output functions might reflect the shortening of the endogenous period observed at the transcriptional level. Moreover, differences in the expression patterns of clock gene in brain and eyestalk, in LD and DD, suggested the presence in krill of a multiple oscillator system. Evidence of short periodicities in krill behavior and physiology further supports the hypothesis that a short endogenous period might represent a circadian adaption to cope with extreme seasonal photoperiodic variability at high latitude.

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

SIL Proceedings 1922-2010 ◽

10.1080/03680770.1987.11899718 ◽

1988 ◽

Vol 23 (2) ◽

pp. 807-811 ◽

Cited By ~ 1

Author(s):

Wilfried Gabriel ◽

Bernhard Thomas

Keyword(s):

Predation Risk ◽

Food Availability ◽

Vertical Migration ◽

Diel Vertical Migration ◽

Evolutionary Stability ◽

Metabolic Costs ◽

Influence Of Food

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Trade-Offs in Diel Vertical Migration by Zooplankton: The Costs of Predator Avoidance

Ecology ◽

10.2307/1940881 ◽

1994 ◽

Vol 75 (8) ◽

pp. 2255 ◽

Cited By ~ 229

Author(s):

Carsten J. Loose ◽

Piotr Dawidowicz

Keyword(s):

Vertical Migration ◽

Diel Vertical Migration ◽

Predator Avoidance ◽

Trade Offs

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5α-cyprinol sulfate, a bile salt from fish, induces diel vertical migration in Daphnia

eLife ◽

10.7554/elife.44791 ◽

2019 ◽

Vol 8 ◽

Cited By ~ 13

Author(s):

Meike Anika Hahn ◽

Christoph Effertz ◽

Laurent Bigler ◽

Eric von Elert

Keyword(s):

Vertical Migration ◽

Diel Vertical Migration ◽

Predator Avoidance ◽

Aquatic Invertebrates ◽

Chemical Cues ◽

Temporal Distribution ◽

Aquatic Environments ◽

Inducible Defenses ◽

Lipid Digestion

Prey are under selection to minimize predation losses. In aquatic environments, many prey use chemical cues released by predators, which initiate predator avoidance. A prominent example of behavioral predator-avoidance constitutes diel vertical migration (DVM) in the freshwater microcrustacean Daphnia spp., which is induced by chemical cues (kairomones) released by planktivorous fish. In a bioassay-guided approach using liquid chromatography and mass spectrometry, we identified the kairomone from fish incubation water as 5α-cyprinol sulfate inducing DVM in Daphnia at picomolar concentrations. The role of 5α-cyprinol sulfate in lipid digestion in fish explains why from an evolutionary perspective fish has not stopped releasing 5α-cyprinol sulfate despite the disadvantages for the releaser. The identification of the DVM-inducing kairomone enables investigating its spatial and temporal distribution and the underlying molecular mechanism of its perception. Furthermore, it allows to test if fish-mediated inducible defenses in other aquatic invertebrates are triggered by the same compound.

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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 of predators (planktivorous fish larvae) and prey (zooplankton) in a tropical lagoon

Iheringia Série Zoologia ◽

10.1590/1678-476620151052174183 ◽

2015 ◽

Vol 105 (2) ◽

pp. 174-183 ◽

Cited By ~ 6

Author(s):

Marcos Marques Mendonça ◽

Pablo Henrique dos Santos Picapedra ◽

Michelli Caroline Ferronato ◽

Paulo Vanderlei Sanches

Keyword(s):

Vertical Migration ◽

Diel Vertical Migration ◽

Predator Avoidance ◽

Fish Larvae ◽

Abiotic Factors ◽

Reproductive Period ◽

Planktivorous Fish ◽

Spatial Overlap ◽

Tropical Lagoon ◽

Small Depth

ABSTRACT Based on the hypothesis that diel vertical migration (DVM) is a mechanism of predator avoidance, the objective of the present study was to test for the occurrence of DVM in planktivorous fish larvae of Hypophthalmus edentatus (Spix, 1829) (Siluriformes, Pimelodidae) and Plagioscion squamosissimus (Heckel, 1840) (Perciformes, Sciaenidae), and zooplankton (rotifers, cladocerans and copepods) in an isolated tropical lagoon in the floodplain of the Upper Paraná River, Brazil (region of Parque Nacional de Ilha Grande). We investigated spatial overlap between predators (planktivorous fish larvae) and prey (zooplankton), and tested which physical and chemical variables of the water are related to the DVM of the studied communities. We performed nocturnal (8:00 pm and 4:00 am) and diurnal sampling (8:00 am and 4:00 pm) in the limnetic region of the lagoon for six consecutive months, from October 2010 to March 2011, which comprises the reproductive period of the fish species analyzed. During the day the larvae tried to remain aggregated in the bottom of the lagoon, whereas at night they tried to disperse in the water column. Especially for cladocerans, the diel vertical migration is an important behavior to avoid predation larvae of H. edentatus and P. squamosissimus once decreased spatial overlap between secured and its potential predators, which corroborates the hypothesis that DVM is a mechanism of predator avoidance. Although significant correlations were observed between the abiotic factors and WMD of microcrustaceans at certain times of day, the effect of predation of fish larvae on zooplankton showed more important in this environment, because the small depth and isolation not allow great variation of abiotic factors seasonally and between strata the lagoon.

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