Abstract
The objective of the research project is to create a conceptual model of blacktailed prairie dog (Cynomys ludovicianus) town ecology which provides information concerning habitat selection in terms of vegetation and soils along the periphery of Badlands National park. The study is designed, as well, to produce information on expansion and reinvasion rates along eradicated town edges, and to document the effect of this rodent upon range conditions in these areas. The study is presently in its 3rd and final year of research. The following report outlines an experiment which was designed to test a model which explains town expansion based upon some rather simple environmental variables. Though it will, no doubt, fall far short of explaining dispersal activities, the model provides a framework upon which management decisions can be based.