Modelling marine populations – from physics to evolution

A Nordic Marine Academy Course

held 10 – 16 October 2005

at Espegrend Field Station, Bergen, Norway

The oceans are changing

• Marine ecosystems are commonly perceived as mechanical systems.

• Perturbations are reversible.

• Species and interactions are constant.

• Regression analysis can predict the future.

TimeTime

??

However…

• Physical conditions go beyond historic ranges.

• Pollutants stress organisms.

• Ecocystems are qualitatively different.

• Depleted stock are not recovering.

Worm, B. and Myers, R.A. 2003. Meta-analysis of cod-shrimp interactions reveals top-down control in oceanic food webs. Ecology, 84, 162-173.

Levitus, S., Antonov, J.I., Boyer, T.P., Stephens, C. 2000. Warming of the World Ocean. Science, 287, 2225-2229.

Heat content in upper 3000 m.

• Several equilibria- also unstable ones.

• Hysteresis – development may follow alternative trajectories.

• Irreversibility?

Regimeshifts

Scheffer, M., Carpenter, S., Foley, J.A., Folke, C., and Walker, B. 2001. Catastrophic shifts in ecosystems. Nature, 413, 591-596.

World catches

Fishing down

Altered ecosystem structure:Kelp forests

Before Before humanshumans

With With humanshumans

EstuariesBefore Before humanshumans

With With humanshumans

Jackson, J.B.C. et al. 2001. Historical overfishing and the recent collapse of coastal ecosystems. Science, 293, 629-637.

Marine ecosystems are increasingly dominated by human intervention

• Climate change, pollution, habitat destruction, fisheries…

• BUT: will mechanisms also change?

• Can we build a predictive science– through understanding mechanisms, – and how they scale from physics to

evolution?

Physical Physical forcingforcingLight,Light,

temperature,temperature,turbulence,turbulence,turbidity,turbidity,salinity,salinity,

pH…pH…

Individual Individual statestateAge, Age, sex,sex,size,size,

energy reserves,energy reserves,position…position…

Trade-offs emerge

A population is A population is a collection of a collection of individuals and individuals and

their actionstheir actions

Patterns emergeEvolutionemerges

Physical Physical forcingforcing

Individual Individual statestate

Trade-offs emerge

A population is A population is a collection of a collection of individuals and individuals and

their actionstheir actions

Patterns emergeEvolutionemerges

Helge DrangeChristoph Heinze

Andy VisserPer JonssonØyvind Fiksen

Christian JørgensenGeir Huse

Espen Strand

Ulf DieckmannBruno Ernande

Mikko Heino, Bruno Ernande,Ulf Dieckmann, Erin Dunlop

Student presentations

Monday: Oceanography, biogeochemical cycles, and phytoplankton

• Kristine Skovgaard Madsen• Ingrid H. Ellingsen• Cecilie Hansen• Olivia Langhamer• Inga Hense• Elin Lindehoff • Wanderson Fernandes de Carvalho

Student presentations

Tuesday: Zooplankton

• Agurtzane Urtizberea• Øystein Varpe• Paolo Simonelli• Thomas Torgersen

Student presentations

Wednesday: Coexistence and speciation

• Martin Pedersen• Sarah Robinson Wolrath• Raul Primicerio• Sigrunn Eliassen• Varvara Fazalova• Guðni Magnús Eiríksson• Jostein Starrfelt• Jan Heuschele

Student presentations

Thursday: Fish early life stages and recruitment

• Krzysztof Świtek• Frode Bendixen Vikebø• Trond Kristiansen• Tian Tian• Ivo Orellana• Gert Virenfeldt• Päivi Laine• Jónas Páll Jónasson• Kjersti Eline Larsen

Student presentations

Saturday: Fisheries-induced evolution

• Davnah Urbach• Paul Venturelli• Anne Maria Eikeset• Shahaama Abdul Sattar• Karin Nilsson• Dorothy Dankel• Geir Halnes• Erin Dunlop

Administrative information

• Travel costs.• Course diploma.• Lock office building from dinner starts until

breakfast is over.• Please be quiet after midnight.• Computers:

– Computer room with printer.– Internet in rooms.

• Discuss, discuss, discuss!

Social information

• Food:– Allergies, vegetarians…– Snack when you like!– …but help us keep the kitchen tidy.

• Soda, beer, and wine.• Sauna (and swimming).• Evening in Bergen.• Shops…

ShopShop

Questions?