ABSTRACT
Space-Time Population Persistence ................................................... 35 3.5 Spread ............................................................................................................. 37
3.5.1 Types of Spread .................................................................................. 37 3.5.2 Estimating Invasive Species Spread ................................................... 38
3.6 Managing Biological Invasions ......................................................................40 3.7 GIS Tutorial: Estimating Spread Rates of Nonnative Species ........................ 42
3.7.1 Introduction ........................................................................................ 42 3.7.2 Calculating Distance to an Initial Outbreak Location........................ 43 3.7.3 Performing OLS Regression Analysis ................................................ 43 3.7.4 Understanding Residuals ....................................................................46 3.7.5 Testing for Spatial Autocorrelation .....................................................46 3.7.6 Calculating Temporal Spread Rates ................................................... 47 3.7.7 Calculating Regional Spread Rates .................................................... 49
3.8 Conclusions .....................................................................................................50 Questions ..................................................................................................................50 Answers to Questions ..............................................................................................50 Acknowledgments .................................................................................................... 51 References ................................................................................................................ 51
Biological invasions constitute a major threat to native-and agro-ecosystems and comprise three processes: arrival, establishment, and spread. Following successful establishment is an evaluation of the potential impact and management options of a nonnative species. Applications based on GIS are valuable tools that allow managers to monitor the arrival, determine successful establishment, and estimate the rate of spread of an invasive species. In this chapter, we describe the population ecology of biological invasions in a general context, focusing mostly on nonnative insects, and address conceptually the use of geospatial tools in facilitating our understanding and management of invasive species. We also include a tutorial demonstrating the utility of GIS tools in estimating invasion speed and understanding the spread dynamics of an introduced nonnative species across a landscape.
