AAbbuunnddaannccee ooff BBiioolluummiinneesscceenntt ssoouurrcceess iinn tthhee ddeeeepp MMeeddiitteerrrraanneeaann SSeeaa Alan Jamieson, Amy Heger & Monty Priede Oceanlab, University of Aberdeen, Scotland, UK. •Objectives: The University of Aberdeen’s Oceanlab is participating in WP5 and WP9 to perform pelagic bioluminescence profile surveys at each site Oceanlab currently has 8 years of bioluminescence profiling experience Preliminary data from the ANTARES and NESTOR sites has been obtained • Two types of bioluminescence in the deep sea: – Bacteria – Steady baseline source of light from bacterial films on structures or on marine snow particles. – Animals – Flashes of light from light organs or extrusion of luminescent material into the water Protozoa - ca 1mm Copepods - ca 1mm Ctenophores - 10mm + tentacles to 100mm Medusae - 1-50cm Salps - Colonies up to 10m long. e.g. Maximum luminescent intensities for copepods 12 Range 0.03-377x1011 mean 56 x 1011 10 8 r e b m 6 u N 4 Flash frequency = <100ms - >600ms 2 Flash duration = 2s - 17s 0 Other; 0.001 0.01 0.1 1 10 100 1000 10000 Jellyfish = 2x1011 photons s-1 -1 11 Photons .s x 10 Crustacean = 1-3x1011 photons s-1 • Bioluminescence sampling techniques Bathyphotometers • Animals tend to flash at unpredictable intervals so the normal way to measure bioluminescence in the water is by stimulation in a flow- through bathyphotometer Count photons/litre PMT Inlet Exhaust Light Pump chamber Pumping Photometers are limited by inlet size and flow rate Bioluminescence sampling techniques ISIT camera/Splat-screen • Bioluminescence is mechanically stimulated by a mesh screen placed in front of a downward looking ultra low-light camera (ISIT = 10-9 ųW/cm-2) • The screen and camera are deployed either on a lander or a CTD probe A B C D A – Ultra-low-light camera B – Power/control unit C – Lamp D – Splat-screen Bathyphotometers vs. splat screen technique Flow Rate 60s detection Threshold Clarke & Kelly (1965) 0.37l.s-1 45 m-3 Geistdoerfer & Vincendeau (1999) 0.5 l.s-1 33 m-3 Widder et al. (1993) HIDEX -BP 16 l.s-1 1 m-3 Priede et al (2006) splat screen >100 l s-1 <0.1 m-3 Sources m-3 0 20 40 60 80 100 0 Most Bathyphotometers 1000 are limited to <1000m ) 2000 m ( h t p e D 3000 HIDEX capable to ca. 3000m 4000 Splat Screen <0.1 m-3 5000 Example profile from NE Atlantic • The number of bioluminescent sources is a function of surface productivity • Measured as Chlorophyll concentration by satellite. • Monthly Chlorophyll data across the Mediterranean Sea • Measured by 4 different sources (POLDER, SeaWiFS, OCTS, CZCS) From Bricaud et al., 2002; Rem. Sens. Env. 81; 163-178 • Bioluminescence profiles at ANTARES Sampling time January May Site number 2 5 2 3 5 Date (dd/mm/yy) 23/01/04 24/01/04 18/05/04 18/05/04 19/05/04 Latitude (N) 42o 48’ 42o 10’ 51” 42o 48’ 42o 44’ 42o 10’ 51” Longitude (E) 6o 10’ 70” 6o 10’ 70” 6o 10’ 70” 6o 10’ 70” 6o 10’ 70” Depth (m) ~2400 ~2400 2494 2442 2479 ANTARES site Site 3 Offshore site • Bioluminescence profiles at ANTARES ANTARES (Jan, '04) ANTARES (May, '04) Bioluminescent events per cubic Bioluminescent events per cubic metre metre 0.1 1 10 0.1 1 10 0 0 500 500 ) 1000 ) 1000 m m ( ( h h t t p p e e D 1500 D 1500 2000 2000 2500 2500 • Profiles revealed an increase in pelagic bioluminescence in May after the spring primary production bloom in the surface waters • Bioluminescence profiles at NESTOR Location: 36o 33.61’N, 21o 02.79’E Greece •4 nm West of KMD sediment trap site •Sounding Depth; 5100m •16th Oct 2006 (night) •FS Meteor M70-1 (HERMES cruise) Bioluminescent events per cubic metre Temperature ( oC) Salinity (ppt) Oxygen (ml/l) 0 0.5 1 1.5 2 2.5 3 13 14 15 38.5 38.7 38.9 3.5 4 4.5 500 500 500 500 1000 1000 1000 1000 1500 1500 1500 1500 2000 2000 2000 2000 2500 2500 2500 2500 ) ) ) ) m m m m ( ( ( ( h h h h t t t t p p p p e e e e D D 3000 D 3000 D 3000 3000 3500 3500 3500 3500 4000 4000 4000 4000 4500 4500 4500 4500 5000 5000 5000 5000 • Bioluminescence profiles ANTARES NESTOR • NESTOR and ANTARES comparison NESTOR (Oct, '06) ANTARES (Jan, '04) ANTARES (May, '04) Bioluminescent events per cubic Bioluminescent events per cubic Bioluminescent events per cubic metre metre metre 0.1 1 10 0.1 1 10 0.1 1 10 0 0 0 500 500 500 1000 1000 1000 1500 1500 1500 2000 2000 2000 ) ) ) m m m ( ( ( h h h 2500 2500 t 2500 t t p p p e e e D D D 3000 3000 3000 3500 3500 3500 4000 4000 4000 4500 4500 4500 Sampled depth 5000 5000 5000 Seafloor • Between 1000 & 2500m the mean events per cubic metre are; NESTOR = 0.12 ANTARES (Jan) = 1.78 ANTARES (May) = 4.4 • Probability of impact on optical modules Current speed (m s-1) 0 0.05 0.1 0.15 0.2 1 Density (events.m-3) 0.1 1 1 - s 2 s t c a 3 p m I 4 0.01 5 6 E.g. Organisms = 0.01m-2 0.001 ( 2 2 % . ø sphere + . ø + impacts = &0 , ) + 0 , animal ) # "/ " z sec , 2 ) 2 ! '& - * - * $# • At typical deep-sea current speeds potential impacts are; 0.6 events.min-1 (density=1m-3) 3 events.min-1 (density=6m-3) • Probability of impact on optical modules Current speed (m s-1) 0 0.05 0.1 0.15 0.2 1 Density (events.m-3) 0.1 1 1 - s 2 s t c a 3 p m I 4 0.01 5 6 E.g. Organisms = 0.01m-2 0.001 Mean events.m-3 impacts.s-1 impacts.min-1 ANTARES (J) 1.78 0.02 1.2 ANTARES (M) 4.4 0.05 3 NESTOR 0.12 0.004 0.24 • Conclusion • At this time, it appears that – there is considerably less bioluminescent activity in the Eastern Med than in the Western Med. – the bioluminescence profiles correlate to surface productivity • Statistically, more profiles are required from the sites. • The NEMO site requires profiling. Winter Spring Summer Autumn ANTARES 2 (2004) 3 (2004) NEMO NESTOR 1 (2006) • Other bioluminescence profiles in the deep Mediterranean Sea • Acknowledgements: J. Carr, S. Escoffier, A. Freiwald, W-C. Dullo, A. Rüggeberg.