1. Markov Chain Modeling of Connectivity for Complex Coastlines Dave Siegel UCSB

2. Why Use Markov Chain Models? Need to know site-to-site connectivity probabilities for real environments Circulation models will take forever Match impedance with other ecological, economic and fleet models Do something simple & stupid

6. How To Markov Chain Islands? Release particles from one patch at a time Advect them following some rules Make sure no particles go on land Count the number of particles who are found within a given patch within their competency interval Repeat for the next release site Sum them all up and normalize

7. A Cheesy Example Based upon an 8 patch Catalina Island Set fluctuating currents at 15 km/d, mean current of 5 km/d & decorrelation time to 2 d Release 5000 particles from each patch “Bounce” those who run ashore Normalize to look at density of releases & the density of settlement

10. Island Markov Chain Model Results Results show expected symmetries –Need larger number of particles Code can be simply extended to other sites –Just need polygon boundaries –Might actually work better for complex domains with many more polygons