Ecology of mesopelagic fish RRS James Clark Ross Cruise 100 th th March 8 -April 5 2004 1 Cover picture: Electrona carlsbergi caught during the cruise. 2 1. INTRODUCTORY SECTION....................................................................8 Background ..................................................................................................................8 Objectives......................................................................................................................9 Summary of Science Activities..................................................................................12 Cruise Narrative.........................................................................................................23 2. PHYSICAL OCEANOGRAPHY..............................................................35 Conductivity-Temperature-Depth (CTD) Operations ...........................................35 Vessel-Mounted Acoustic Doppler Current Profiler (VM-ADCP) .......................45 Oceanlogger (Underway Measurements) ................................................................52 Navigation Data..........................................................................................................53 Expendable Bathythermographs (XBT’s) ...............................................................59 Acknowledgements ....................................................................................................59 3. ACOUSTICS...........................................................................................61 Introduction................................................................................................................61 Aims.............................................................................................................................61 Methods/system specification....................................................................................62 Data coverage .............................................................................................................67 Problems encountered ...............................................................................................68 Future Plans ...............................................................................................................70 References...................................................................................................................70 4. FISH AND CEPHALOPOD CATCHES ..................................................74 Background ................................................................................................................74 Fishing gears...............................................................................................................74 Catch Processing ........................................................................................................75 Fish and cephalopod catch composition ..................................................................75 3 5. THE VISUAL ECOLOGY OF ANTARCTIC MESOPELAGIC FISH .......79 Introduction................................................................................................................79 Aims.............................................................................................................................79 Methodology ...............................................................................................................79 Results .........................................................................................................................81 Discussion and further work.....................................................................................84 Acknowledgements ....................................................................................................85 References...................................................................................................................85 6. BIOCHEMICAL AND PHYSIOLOGICAL ANALYSIS OF ANTIOXIDATIVE DEFENCE MECHANISMS IN DEEP-SEA FISH...............86 Introduction................................................................................................................86 Objectives....................................................................................................................86 Methods.......................................................................................................................87 Future Experiments...................................................................................................88 7. SEABIRD AND MARINE MAMMAL SURVEYS ....................................89 Introduction................................................................................................................89 Survey coverage .........................................................................................................89 Seabirds.......................................................................................................................91 Marine mammals .......................................................................................................99 Floating matter.........................................................................................................101 Summary...................................................................................................................101 Acknowledgements ..................................................................................................102 References.................................................................................................................102 8. BONGO NET ACTIVITIES ...................................................................104 Gear and deployment protocol ...............................................................................104 Live-material analyses.............................................................................................105 Extraction and preservation of material for genetic analysis (CC) ....................109 4 Copepod reproductive biochemistry (DP).............................................................111 Food web analysis (DP) ...........................................................................................112 9. KRILL STUDIES...................................................................................113 Population dynamics................................................................................................113 Results .......................................................................................................................114 Stomach content and biochemical analyses...........................................................115 10. GEAR REPORT................................................................................116 RMT25 ......................................................................................................................116 RMT8 ........................................................................................................................116 LHPR ........................................................................................................................117 Down Wire Net Monitor..........................................................................................117 UOR...........................................................................................................................118 11. AFI 3/16 MOORINGS REPORT........................................................120 Background, aim and methodology .......................................................................120 Recovery and redeployment during JR 100 ..........................................................120 Monitoring problem with the ARGOS beacon 35520 ..........................................121 Data verification.......................................................................................................122 Work carried out......................................................................................................122 New Instrument settings (general) .........................................................................122 12. CHLOROPHYLL, PHYTOPLANKTON AND POC SAMPLING .......124 Introduction..............................................................................................................124 Methods.....................................................................................................................124 Data ...........................................................................................................................125 13. WESTERN CORE BOX NETTING ...................................................127 Protocols....................................................................................................................127 Catch Processing ......................................................................................................127 5 14. LONGHURST-HARDY PLANKTON RECORDER ...........................130 Introduction..............................................................................................................130 LHPR performance .................................................................................................131 15. AT SEA OBSERVATIONS ON FUR SEAL DISTRIBUTION............133 Introduction..............................................................................................................133 Aim ............................................................................................................................133