1. A dynamic stochastic food web model for the Barents Sea Benjamin Planque and Ulf Lindstrøm

2. A “reference” ecosystem model Food Web Mass balanced
Fluctuations in the Barents Sea Ecosystem state:
are they part of the ‘natural dynamics’
or are we seeing regime shifts?
A “reference” ecosystem model
Food Web
Mass balanced
Constraints: physiology & life span
Stochastic
Simple, fast, transparent
“Null” model to test ecosystem metrics for resilience
Cop.
Euph.
Phytopl.
Cod
Minke
whales
Capelin

3. First results Trophic functional relationships Temporal dynamics
Diet analysis

4. First results Bottom-up Top-down Bottom-up Top-down Alternance of
periods?
Top-down
Bottom-up
Top-down

5. Conclusions Prototype for the Barents Sea
Set a reference for expected ecosystem properties under a minimal set of assumptions
Can be used as an experimental tool to evaluate resilience of the Barents Sea Ecosystem to climate and fishing perturbations