Robert "Bill" Provencher

University of Wisconsin
416 Taylor Hall
427 Lorch Street
Madison, WI 53706
(608) 262-9494

Research Projects

Surprises - large, unexpected changes from apparently small causes -- are common in systems of people and nature. Are these surprises a consequence of the complexity or nonlinearity of natural-social systems? Or can they be explained by simpler processes? Our research addresses this question for systems composed of lakes, their shoreline (riparian) vegetation and land use, and social and economic organizations of lake users. We will study the self-organization of lake users and associated characteristics of shoreline and lake ecosystems. We will determine whether thresholds in riparian organization set the stage for an important class of surprises - collapses of economically important game fish stocks. We will test the possibility that nonlinear dynamics can be used to design manipulations that remove invading crayfish from a lake. If successful, our experiment will cause a self-sustaining removal of an invasive species - a path-breaking ecological restoration.

Invasive species are often a major threat to native species and biodiversity, and consequently to the social value of ecosystems. In the absence of good modeling of the economics and ecology of human-caused species dispersal, identifying management policies that best serve social objectives with respect to the control and prevention of the spread of invasive species is unlikely if not impossible. This project develops an integrated economic and ecological model to examine the spread of aquatic invasive species (AIS) in a freshwater lake system where recreational boaters are the principle vector of dispersal. The model is applied to an investigation of a large lake system in northern Wisconsin.

An important aspect of aquatic invasive species (AIS) management is the role humans play in their dispersal. For the spread of AIS among inland lakes, the typical pathway for dispersal is boaters moving from lake to lake. We aim to develop a spatial dynamic model of species invasions within a freshwater lake system in which a set of managing agents is concerned with the inter-seasonal spread of invasive species across lakes (where a season is defined in this case as the annual boating season), and recreational boaters/anglers make a series of intra-seasonal trip decisions to maximize random utility during the course of the season, subject to the actions taken by the manager.