Early Warn­ing Signs and Crit­i­cal Tran­si­tions in Ecol­ogy: Corals, The­ory, Pit­falls, and Advances

I will start by describ­ing spe­cific eco­log­i­cal sys­tems that have mul­ti­ple sta­ble states, lakes and coral algal grazer sys­tems giv­ing mod­els of the lat­ter. I will then dis­cuss approaches for pre­dict­ing sud­den shifts in the face of slow para­me­ter change. The approach will depend on devel­op­ing a sim­ple sto­chas­tic model and using this model to describe the data. A key ele­ment in describ­ing the results will be the use of receiver-operator curves. This part of the talk will include both pos­si­bil­i­ties and pit­falls. I will then dis­cuss how the use of data can both help and be mis­lead­ing in judg­ing the effi­cacy of warn­ing signals.

Speaker: Alan Hastings, UC Davis