Invasive species cost billions of dollars annually, causing damage to agriculture, the environment and the economy as a whole. Countries and states have elaborate biosecurity systems to prevent entry and spread of pests, diseases and weeds, but quarantine measures sometimes fail and incursion responses are initiated to attempt eradication of unwanted entries. The success of an eradication program ultimately depends on the ability to find pests and prevent reproduction. Search theory can help design efficient surveillance programs to contribute to eradication.

Search theory is one of the oldest areas of operations research. The basic search problem is to find an allocation of effort in space that maximises the probability of finding a target subject to a constraint on effort. In this seminar, I will present the basics of search theory and provide examples of control programs that may combine people, detector dogs, remote sensing, drones and other tools to improve the efficiency of incursion responses. In addition, I will present work in progress on eradication of weeds in collaboration with National Parks.

Oscar Cacho is Professor of Agricultural and Resource Economics at UNE Business School, University of New England. He started his professional life as a marine biologist and later branched into economics. His research interests centre on the application of Bioeconomics to interesting problems in agriculture and natural resources. His recent work has been in two major areas: the economics of biosecurity to protect native ecosystems, and climate-change economics and policy with focus on land use change and forestry in tropical countries. He is a regular consultant to the Food and Agricultural Organisation of the United Nations (FAO), and collaborates with other national and international agencies on these and other topics.