Introduction

This chapter considers the use of specific, as opposed to general, models in biological control. General models are considered by Berryman in Chapter 1 and Briggs et al. in Chapter 2. The term specific is used in preference to ‘tactical’ because ‘tactical’ carries connotations of real-time use. Here I consider models applied to particular real-world systems or to very specific questions about such systems in general. Having outlined the potential benefits of such models for the practice of biological control, 50 biological control models from the literature are tabulated and briefly discussed. These cover a range of different biological control systems, and critical comment is made where appropriate on aspects of interest or concern relating to the specific case histories or to the particular approaches adopted. Finally, some conclusions are drawn from the survey, in terms of the types of approaches adopted in the past, types of systems addressed and, in particular, how the modeling has matched its theoretical potential to aid in practical biological control. This potential embodies the following benefits:

1. Predicting the outcome and success of a specific introduction.

2. Predicting the impact of introduced agents on ecosystems and non-target species.

3. Aiding in the selection of the most appropriate agent(s).

4. Predicting optimum release and management strategies.

5. Aiding in the identification and interpretation of critical field data.

6. Increasing understanding of the processes involved and the reasons for success or failure.