Feeding Ecology of the Arctic Ice-Amphipod Gammarus wilkitzkii. Physiological, Morphological and Ecological Studies, Svalbard September 2000Entry ID: ArcOD_2008I1
Abstract: Gammarus wilkitzkii is a presumed omnivorous amphipod that lives in high densities in close association with Arctic pack ice. This dataset consist of 7 rows and 4 species (Apherusa glacialis, Gammarus wilkitzkii, Onisimus nanseni and Onisimus glacialis). The data are derived from a study that tried to illuminate the complexity of food ecology in more detail for G.wilkitzkii and in terms of food ... detection, food localization, food preference, feeding mechanism, ingestion and digestion. This study combines several experiments, in field and laboratory, with special emphasis on physiology, behaviour and morphology. Sampling took place in September 2000 in the pack-ice north of Svalbard. At three ice stations of each 24 hours duration eight traps baited with different food types were fixed at the ice edge and below the ice. The total number of amphipods caught at all locations was 15. Most of the specimens were attracted by those traps attached at the under-ice surface and baited with rotten polar cod. They belonged to the genera Onisimus. Even though abundance (and biomass) was recorded highest for G.wilkitzkii at all three stations this amphipod was only seldom attracted by baited traps. Compared to previous studies the density and biomass data at this sampling side was remarkably reduced, probably due to recent melting and re-freezing processesand the specific re-colonisation abilities of sympagic amphipods. Since bait experiments resulted in extremely low numbers of attracted amphipods food preference studies were carried out in the laboratory with specimens sampled by SCUBA divers. The most preferred food type was deduced from oxygen consumption rates after exposing the amphipod to homogenates made of plant, animal or detrital material. Fourteen adults (of both sexes) and thirteen juveniles were incubated in a closed bottle set-up for 18 hours. Some experimental set-ups with a wide spectrum of food types including conspecific living and dead amphipods revealed, that G. wilkitzkii rejected none of the food types primarily and ingested even foreign material of no nutritional value. Morphological studies on mouthparts and accessory feeding appendages by means of SEM confirm a more unspecific food ecology of G.wilkitzkii.
Purpose: Data come from a study that tries to investigate the feeding and digestion habits, preference, mechanisms, localization, and detection of Gammarus wilkitzkii.
Data Set Citation
Dataset Originator/Creator: Carolin E. Arndt
Dataset Title: Feeding Ecology of the Arctic Ice-Amphipod Gammarus wilkitzkii. Physiological, Morphological and Ecological Studies, Svalbard September 2000
Dataset Series Name: Reports on Polar Research
Dataset Release Date: 2002
Issue Identification: 405Online Resource: http://ak.aoos.org/ArcOD/data_table.php
This data set description is a member of a collection. The collection is described in
Start Date: 2000-09-22Stop Date: 2000-09-25
Quality ATTRIBUTE ACCURACY REPORT: The animal counts were done according to convention (for details ask authors): sorting under a stereo microscope after preservations. Geographical positions were taken from the publication. Spatial accuracy is unknown.
LOGICAL CONSISTENCY REPORT: The same procedures were used at all sites and for all species; findings should be consistent.
COMPLETENESS ... REPORT: Core samples were 7.6 cm in diameter and the bottom 3+-1 cm. Only the bottom of the samples was used.
PROCESS DESCRIPTION: applicable since fully explained in Methodology: see above
PROCESS DESCRIPTION: Fixed collection code in meta data; changed capitalization of title of file; changed scientificnamauthour to scientificnameauthor [does not appear to be used anywhere.]
Access Constraints None
Use Constraints Although these data have been processed successfully on a computer system at the University of Alaska and ArcOD, no warranty expressed or implied is made regarding the accuracy or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. This disclaimer applies both to individual use of the data and aggregate use ... with other data. It is strongly recommended that these data are directly acquired from a University of Alaska server, and not indirectly through other sources which may have changed the data in some way. It is also strongly recommended that careful attention be paid to the contents of the metadata file associated with these data. The University of Alaska shall not be held liable for improper or incorrect use of the data described and/or contained herein.
Data Set Progress
Distribution Format: XLS
Role: TECHNICAL CONTACT
Fax: +01-907 4746967
Email: fhuettmann at alaska.edu
419 Irving I, PO Box 757000
Province or State: AK
Postal Code: 99775-7000
Role: DIF AUTHOR
Email: alicia.m.aleman at nasa.gov
Goddard Space Flight Center Code 610.2
Province or State: MD
Postal Code: 20771
Creation and Review Dates
DIF Creation Date: 2008-01-11
Last DIF Revision Date: 2010-02-24