The three-dimensional prey field of the northern krill, Meganyctiphanes norvegica, and the escape responses of their copepod prey
In the north Atlantic, Meganyctiphanes norvegica feeds predominantly on copepods, including Calanus spp. To quantify its perceptual field for prey, and the sensory systems underlying prey detection, the responses of tethered krill to free-swimming Calanus spp. were observed in 3D using silhouette vi...
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ftimr:oai:imr.brage.unit.no:11250/108585 2023-05-15T17:10:42+02:00 The three-dimensional prey field of the northern krill, Meganyctiphanes norvegica, and the escape responses of their copepod prey Abrahamsen, Mari B. Browman, Howard I. Fields, David M. Skiftesvik, Anne Berit 2010-02-24 application/pdf http://hdl.handle.net/11250/108585 https://doi.org/10.1007/s00227-010-1405-9 eng eng Springer Berlin / Heidelberg urn:issn:0025-3162 http://hdl.handle.net/11250/108585 http://dx.doi.org/10.1007/s00227-010-1405-9 1251-1258 157 Marine Biology 6 krill copepods copepoda ecosystem models økosystemmodeller VDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497 Journal article Peer reviewed 2010 ftimr https://doi.org/10.1007/s00227-010-1405-9 2021-09-23T20:16:05Z In the north Atlantic, Meganyctiphanes norvegica feeds predominantly on copepods, including Calanus spp. To quantify its perceptual field for prey, and the sensory systems underlying prey detection, the responses of tethered krill to free-swimming Calanus spp. were observed in 3D using silhouette video imaging. An attack–which occurred despite the krill’s being tethered—was characterized by a pronounced movement of the krill’s antennae towards the target, followed by a propulsion and opening of the feeding basket. Frequency distributions of prey detection distances were significantly different in the light vs. the dark, with median values of 26.5 mm and 19.5 mm, respectively. There were no significant differences in the angles at which prey were detected by krill (relative to the predator’s longitudinal body axis) in the light vs. the dark. Prey detections were symmetrically distributed on either side of the predator, in both light and dark. However, significant asymmetry was found in the dorsal–ventral direction with 80% of the prey detections located below the midline of the krill’s body axis and, given the placement and orientation of the compound eyes, presumably outside its visual field of view. This indicates that, at least under these conditions, vision was not the main sensory modality involved in the detection of active prey by M. norvegica. However, under some circumstances, vision may provide supplemental information. Avoidance responses of copepod prey were nearly twice the velocity of their nominal background swimming speed (153 ± 48 and 85 ± 75 mm s−1, respectively), on average taking them 43 ± 16 mm away from the predator. This is far beyond the krill’s perceptual range, suggesting that the escape reaction provides an effective deterrent to predation (although perhaps less so for free-swimming krill). This information can be used to parameterize models that assess the role of krill as predators in marine ecosystems. Article in Journal/Newspaper Meganyctiphanes norvegica North Atlantic Northern krill Copepods Institute for Marine Research: Brage IMR Marine Biology 157 6 1251 1258 |
institution |
Open Polar |
collection |
Institute for Marine Research: Brage IMR |
op_collection_id |
ftimr |
language |
English |
topic |
krill copepods copepoda ecosystem models økosystemmodeller VDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497 |
spellingShingle |
krill copepods copepoda ecosystem models økosystemmodeller VDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497 Abrahamsen, Mari B. Browman, Howard I. Fields, David M. Skiftesvik, Anne Berit The three-dimensional prey field of the northern krill, Meganyctiphanes norvegica, and the escape responses of their copepod prey |
topic_facet |
krill copepods copepoda ecosystem models økosystemmodeller VDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497 |
description |
In the north Atlantic, Meganyctiphanes norvegica feeds predominantly on copepods, including Calanus spp. To quantify its perceptual field for prey, and the sensory systems underlying prey detection, the responses of tethered krill to free-swimming Calanus spp. were observed in 3D using silhouette video imaging. An attack–which occurred despite the krill’s being tethered—was characterized by a pronounced movement of the krill’s antennae towards the target, followed by a propulsion and opening of the feeding basket. Frequency distributions of prey detection distances were significantly different in the light vs. the dark, with median values of 26.5 mm and 19.5 mm, respectively. There were no significant differences in the angles at which prey were detected by krill (relative to the predator’s longitudinal body axis) in the light vs. the dark. Prey detections were symmetrically distributed on either side of the predator, in both light and dark. However, significant asymmetry was found in the dorsal–ventral direction with 80% of the prey detections located below the midline of the krill’s body axis and, given the placement and orientation of the compound eyes, presumably outside its visual field of view. This indicates that, at least under these conditions, vision was not the main sensory modality involved in the detection of active prey by M. norvegica. However, under some circumstances, vision may provide supplemental information. Avoidance responses of copepod prey were nearly twice the velocity of their nominal background swimming speed (153 ± 48 and 85 ± 75 mm s−1, respectively), on average taking them 43 ± 16 mm away from the predator. This is far beyond the krill’s perceptual range, suggesting that the escape reaction provides an effective deterrent to predation (although perhaps less so for free-swimming krill). This information can be used to parameterize models that assess the role of krill as predators in marine ecosystems. |
format |
Article in Journal/Newspaper |
author |
Abrahamsen, Mari B. Browman, Howard I. Fields, David M. Skiftesvik, Anne Berit |
author_facet |
Abrahamsen, Mari B. Browman, Howard I. Fields, David M. Skiftesvik, Anne Berit |
author_sort |
Abrahamsen, Mari B. |
title |
The three-dimensional prey field of the northern krill, Meganyctiphanes norvegica, and the escape responses of their copepod prey |
title_short |
The three-dimensional prey field of the northern krill, Meganyctiphanes norvegica, and the escape responses of their copepod prey |
title_full |
The three-dimensional prey field of the northern krill, Meganyctiphanes norvegica, and the escape responses of their copepod prey |
title_fullStr |
The three-dimensional prey field of the northern krill, Meganyctiphanes norvegica, and the escape responses of their copepod prey |
title_full_unstemmed |
The three-dimensional prey field of the northern krill, Meganyctiphanes norvegica, and the escape responses of their copepod prey |
title_sort |
three-dimensional prey field of the northern krill, meganyctiphanes norvegica, and the escape responses of their copepod prey |
publisher |
Springer Berlin / Heidelberg |
publishDate |
2010 |
url |
http://hdl.handle.net/11250/108585 https://doi.org/10.1007/s00227-010-1405-9 |
genre |
Meganyctiphanes norvegica North Atlantic Northern krill Copepods |
genre_facet |
Meganyctiphanes norvegica North Atlantic Northern krill Copepods |
op_source |
1251-1258 157 Marine Biology 6 |
op_relation |
urn:issn:0025-3162 http://hdl.handle.net/11250/108585 http://dx.doi.org/10.1007/s00227-010-1405-9 |
op_doi |
https://doi.org/10.1007/s00227-010-1405-9 |
container_title |
Marine Biology |
container_volume |
157 |
container_issue |
6 |
container_start_page |
1251 |
op_container_end_page |
1258 |
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1766067349239103488 |