NEW VERSION OF LSTSIM FOR COMPUTER-SIMULATION OF AMBLYOMMA-AMERICANUM(ACARI, IXODIDAE) POPULATION-DYNAMICS

A previous version of Lone Star Tick Simulation Model (LSTSIM) for a w ildlife ecosystem was revised and expanded to include a beef cattle fo rage area and improved handling of tick-host-habitat interactions. Rel ationships between environmental and biological variables were also re fined in the new version. General validity of the revised model was es tablished by comparing simulated and observed host-seeking populations of Amblyomma americanum (L.) at five geographic locations, three in O klahoma and two in Kentucky-Tennessee. Additional validity was indicat ed from comparisons of simulated and observed seasonality of lone star ticks at one location in Kentucky. The model produced acceptable valu es for initial population growth rate, generation time, and 15-yr popu lation density when historical weather files for 14 locations in the U nited States were used. The model of A. americanum population dynamics was used to study the relationship between tick density and density o f white-tailed deer, Odocoileus virginianus (Zimmerman), and cattle. T he revised model can be used for additional simulation studies on effe cts of tick control technologies and integrated management strategies.