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.
Estimation of the model, and the data required for estimation, focuses on three elements: the Random Utility Model of boater trip decisions, the transmission probability density functions, and the abundance of AIS (see project 'Aquatic invasive species in NHLD').
Estimation of the random utility model (RUM) of boater trip decisions:
The sample data of boater trips required for this estimation is being collected during 2011 via a boater trip diary program. The survey sample is drawn from boaters intercepted at boat landings in the study area. Boaters are asked to record every trip taken during the season, mailing in their booklets at the end of each month. The data collected from respondents include the trip date and cost, lake choice, and fish catch for all trips taken during the season. At the end of the season, a follow-up mail questionnaire will solicit information on demographic characteristics, such as employment status and income, and participants attitudes and opinions regarding the management of AIS. Furthermore, stated preference questions will also be used to help predict boater responses to new infestations of AIS and corresponding shifts in lake management.