Aggregations of Arctic deep-sea scavenging amphipods at large food falls
The aim of the present study is to elucidate the feeding ecology of Eurythenes gryllus (Crustacea: Amphipoda) in the Arctic deep sea. Literature data show that this species occurs frequently and in high numbers at food falls, so it was likely to obtain data on its food finding strategies and, its ag...
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| Other Authors: | , , |
| Format: | Doctoral or Postdoctoral Thesis |
| Language: | English |
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Universität Bremen
2003
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| Online Access: | https://media.suub.uni-bremen.de/handle/elib/2037 https://nbn-resolving.org/urn:nbn:de:gbv:46-diss000010103 |
| Summary: | The aim of the present study is to elucidate the feeding ecology of Eurythenes gryllus (Crustacea: Amphipoda) in the Arctic deep sea. Literature data show that this species occurs frequently and in high numbers at food falls, so it was likely to obtain data on its food finding strategies and, its aggregation dynamics at food falls, which could be combined with information on its metabolism under controlled conditions in aquaria experiments. Six large food fall experiments were carried out during expeditions with the RV Polarstern in the Arctic summer seasons 2000 and 2001 between 1400 and 2600 m water depth. For in situ investigations a tripod lander was used equipped with a baited time-lapse camera, a scanning sonar system (SSS), an acoustic doppler current profiler and baited traps.Scanning sonar data demonstrate that the amphipods swim upstream along a narrow path towards the bait. Thus, in combination with current measurements and time-lapse photography this study shows that chemoreception serves for food fall localization in the scavenging amphipod Eurythenes gryllus over relatively large distances. The findings of the investigations in situ were supported by results of respiration rate measurements in E. gryllus indicating an increase in oxygen consumption after exposure to food odour in laboratory experiments. Based on total lipids (6.1 % of wet weight) and metabolic rates, sustenance times have been calculated. The results of this study are encourage future use of these acoustic and optical combined instruments. Eurythenes gryllus must be regarded as an important component of the deep-sea food web due to their feeding efficiency, their large number attracted and their role in the consumption. To get a more detailed idea of the deep-sea community it could be useful to apply this methodological approach also in other latitudes. |
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