Isle Royale: portage; moose; the flattened grass is a moose bed.
MooseWood Home


This simulator uses Forska, a boreal forest simulator, to provide the landscape base for Gecko, an individual based ecosystem simulator. Gecko is providing the user interface and spatial structure and (eventually) herbivores and carnivores. Forska provides climate change and tree species data, and simulates the patches of forest within each hexagon.

Gecko Forska is a baseline for a global warming project on Isle Royale, Lake Superior, for Oswald Schmitz of the Yale School of Forestry. This work is generously funded by the Noble Foundation.


Forska was originally written in Fortran by Rik Leemans. This source code was extended and modified by a number of people, sometimes divergently. Gecko Forska began with the Fortran provided by David T. Price, for Forska2v. Ginger Booth translated that to Java in August 2002, verifying the translation to give exact same results as the Fortran, down to the same random number sequence, to time 86, after which time the results seem to diverge trivially.

We'd like to thank David Price, Rik Leemans, Allen Solomon, Marcus Lindner, Martin Sykes, and Harald Bugmann, of the Forska community for their help.



Booth, G. (1997) Gecko: A continuous 2-D world for ecological modeling. Artificial Life Journal 3:3 147-163. Text Postscript (174k) and figures Postscript (423k).

Bugmann, H., M. Lindner, P. Lasch, M. Flechsig, B. Ebert, and W. Cramer (2000) Scaling issues in forest succession modelling. Climatic Change 44: 265-289.

Bugmann, H. (2001) A review of forest gap models. Climatic Change 51: 259-305.

Peterson, R.O. and J.A. Vucetich (2002) Ecological Studies of Wolves on Isle Royale, Annual Report 2001-2002. Michigan Technological University, Houghton, Michigan, USA.

Price, D.T., D.H. Halliwell, M.J Apps, and C.H. Peng (1999) Adapting a patch model to simulate the sensitivity of Central-Canadian boreal ecosystems to climate variability. J. Biogeography 26:1101-1113.

Price, D.T., C. H. Peng, M. J. Apps, and D. H. Halliwell (1999) Simulating effects of climate change on boreal ecosystem carbon pools in central Canada. J. Biogeography 26:1237-1248.

Schmitz, OJ (2000) Combining field experiments and individual-based modelling to identify the dynamically relevant organizational scale in a field system. Oikos 89:471-484.

Schmitz, OJ (2001) From interesting details to dynamical relevance: toward more effective use of empirical insights in theory construction. Oikos 94:39-50.

Shugart, H.H., R. Leemans, and G.B. Bonan eds. (1992) A Systems Analysis of the Global Boreal Forest. Cambridge University Press, New York, NY, USA.

IS92a Global [CO2] Yearly Dataset - v.1 (1999). Atmospheric CO2 levels, by year, projected to 2100.

USGS - National Park Service Vegetation Mapping Program (2002) Vegetation/map for Isle Royale.

USHCN - United States Historical Climatology Network (2002). Climate data for Mott Island, Michigan - Isle Royale.

VEMAP, the Vegetation/Ecosystem Modeling and Analysis Project (2002). Climate change scenarios data.

Ginger Booth, February, 2003