Applying Search Theory to Evaluate Eradicating an Invasion (Oscar Cacho)
Channel: Ronald Cannarella
Date: 02/06/2012

A presentation at the Hawai`i Conservation Conference by Oscar Cacho (University of New England, Armidale, NSW, Australia) on "Applying Search Theory to Evaluate the Feasibility of Eradicating an Invasion". The detectability of invasive organisms influences the costs and benefits of alternative control strategies, and the feasibility of eradicating an infestation. Search theory offers a mathematically rigorous framework for defining and measuring detectability, taking account of searcher ability, biological factors and the search environment. In this paper, search theory concepts are incorporated into a population model and the costs of search and control are calculated as functions of the amount of search effort (the decision variable). Simulations are performed on a set of weed scenarios in a natural environment, involving different combinations of plant longevity, seed longevity and plant fecundity. Results provide preliminary estimates of the cost and duration of eradication programs to assist in prioritizing weeds for control. The analysis shows the importance of collecting information on the labor and chemical inputs required to control invasions (as functions of plant density and size), in order to improve the efficiency of invasive control programs.

Hawaii Conservation Alliance
Executive Producer: Ronald Cannarella