Calanus species in the Arctic Mediterranean: from life history to ecosystem dynamics
Hein Rune Skjoldal Institute of Marine Research, Bergen, Norway Outline
• Preludium – looking back • Main part – Three Calanus species – finmarchicus, glacialis, hyperboreus- Life history features – Habitat characteristics – Nordic Seas and Arctic Ocean – Ecosystem dynamics – Barents Sea and Norwegian Sea LMEs • Epilogue – some concluding remarks Life in pelagial – open space * Be small with rapid turnover * Hide in the deep dark PRO MARE
Balsfjorden MARE COGNITUM
St. M
Lindåspollene
Korsfjorden
Firth of Clyde
Barents Sea
Norwegian Sea W - Whelping area seals
wB
B w B – Wintering area Bowhead w and/or beluga wB B
w Pro Mare Temperature Kola section Mare Cognitum 20 2.0
18 1.8 Mare 16 Cognitum 1.6
14 1.4
12 1.2
10 Pro 1.0 Mare
8 0.8
Fangst(mill. tonn) Bestand (mill. tonn) 6 0.6
4 0.4
2 0.2
0 0.0 1951 1956 1961 1966 1971 1976 1981 1986 1991 1996 2001 2006
Gytebestand Umoden bestand Føre-var gytebestand Fangst
Calanus finmarchicus Monoculus finmarchicus by Gunnerus 1770
Calanus hyperboreus Krøyer 1838
Calanus glacialis Jaschnov 1955
Sars 1903 Ruud 1929 Marshall and Orr 1955 (1972) Sømme 1934 The biology of a marine Wiborg 1954 copepod Østvedt 1955
1000 + papers On the biology of - Conover Calanus finmarchicus - Hirche I-XIII – 1933-1966 - Tande - Runge - Melle - Heath - Head -and many others !! Growth
• Exponential growth – copepodites different from nauplii • Equiproportional rule • Allometric – weight-specific decline • Temperature dependent – Bèhlerádek’s equation (development time) – Generation length 1 5 mo for 10 to 0 C Size
• Variation within stage – By an order of magnitude in weight – By a factor 2 in linear dimension • Individual – normal distribution • Within stage – factor ca 3 • Sex – bimodal • Temperature (latitude) - decrease • Food - increase Growth of Calanus species copepodites Dry weight – ug per individual
10000 finmarchicus glacialis CV fin = 1000 CIV glac = hyperboreus CIII hyp
100
10
1 CI CII CIII CIV CV CVI Growth of Calanus species copepodites Dry weight – ug per individual
5000 finmarchicus Wintering 4000 glacialis
3000 hyperboreus
2000
1000
0 Predation CI CII CIII CIV CV CVI Marshall et al. 1934 – Loch Striven, Clyde Sea
400 G2 350 G1 G3 300 250 200 150
100 Female
50 CV 0 17 30 44 66 86 100114128142156170184198212226240275 F M A M J J Wintering
• Dormant, inactive state – diapause? • Maturation process ongoing • Active metabolism reflected in weight loss • Ca 0.5 ug dry weight per day at 4C • Apparently Lower than predicted from respiration - Saumweber and Durbin 2006 • Limited capacity for wintering in a non-feeding state – they burn up through metabolism Weight loss (dry weight ind-1) of CV Calanus finmarchicus CV through winter
400
350
300 Marshall 250 CV mean 200 Tande Small 150 Large 100 Mean Tande
50
0 0 200 400 600 Weathership Halldal 1953 Station ’M’
Weekly sampling Oct 1948 – Nov 1949
Østvedt 1955 Melle and Skjoldal 1998 Arctic – 0C 5-6 mo
Ca. 3-4 mo – June-Sept
3.5-4 mo
Atlantic - 6C 2-2.5 mo Mixed – 2C
Ca. 5 months – April- Sept Calanus hyperboreus Dry weight ug ind-1
6000
5000
4000
3000
2000 CV 1000 Ad fem 0 0 100 200 300 400 Life cycle – Calanus hyperboreus
Wi Su Wi Su Wi
CI CII CIII CIV CIII CIV CV CVI Nauplii CVI Egg Egg
CVI- CIII im CIV CVI-mat CV CVI-mat CVI-im Selected for Calanus large size – glacialis ’no fish’ Calanus hyperboreus
Calanus finmarchicus
Selected for minimum size
WGICA
WGIBAR
WGINOR
Integrated Ecosystem Assessment Groups in ICES Capelin Polar cod - Boreogadus
Mackerel
Herring
Blue whiting
Myctophid
Distribution and overlap of mackerel and herring
Survey design 2015
Hydrography and plankton stations Bottom and pelagic trawl stations Biomass distribution- PINRO/IMR
2014 - 6.7 gm-2 (232 st.) 2014 2013 – 7.1 gm-2 (305 st.) 2012 – 7.6 gm-2 (287 st.)
2013 2012 Pro Mare capelin 1983-herring Zooplankton biomass g dry weight m-2
14.00
12.00
10.00
8.00 Zoopl biomass total Zoopl medium 6.00 Zoopl small Zoopl large
4.00
2.00
0.00
1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 Bowhead Atlantic inflow
Polyakov et al. (2012) Journal of Climate