Risk Analysis, Vol. 31, No. 12, 2011 DOI: 10.1111/j.1539-6924.2011.01607.x Using Simulation to Evaluate Time to Detect Incursions in Honeybee Biosecurity in Australia David Clifford, 1,* Simon Barry, 1 David Cook, 2 Rob Duthie, 3 and Denis Anderson 2 A key determinant of the efficiency of a surveillance system for exotic mites is whether an incursion might be detected sufficiently quickly to allow successful management actions to occur. To assess this possibility we have developed a spatial modeling system and synthesized knowledge of honeybee and mite behavior to explore the potential spread of exotic mites and the likelihood of their detection in sentinel hives. We find that increasing the number of hives and the efficiency of the detection method are the most effective means of improving the time to detection. KEY WORDS: Apis cerana; Apis mellifera; simulation study; varroa 1. INTRODUCTION The Australian honeybee industry produces honey and other bee products for domestic consump- tion and export through apiculture using the Euro- pean honeybee, Apis mellifera. The industry has an estimated gross value of production (GVP) of A$80 million. (1) In addition, the annual benefit of the api- culture industry to general agriculture through plant pollination is estimated to range from A$4 to 6 bil- lion. (1) The 5-year average for the annual gross value of production of 25 horticulture industries depen- dent upon pollination by A. mellifera is $3.9 billion. Thus, even a 10% reduction in production as a result of a pest or disease incursion would result in losses exceeding $350 million per annum (East, Personal Communication, 2009). Australia is free of several important disease- causing honeybee mites and other pests of honey- 1 CSIRO Mathematics, Informatics and Statistics, Australia. 2 CSIRO Ecosystem Sciences, Canberra, ACT, Australia. 3 Kalang Pty. Ltd., NSW, Australia. ∗ Address correspondence to David Clifford, CSIRO Mathematics, Informatics and Statistics, Ecosciences Precinct, PO Box 2583, QLD 4001, Australia; david.clifford@csiro.au. bees. Exotic mites include the varroa mite (Varroa destructor and V. jacobsoni), mite (Tropilaelaps mer- cedesae and T. clareae), and tracheal mite (Acarapis woodi). Other pests of honeybees (through natural competition) include several species of exotic bees including the Asian cavity-nesting honeybee (Apis cerana), giant Asian honeybee (Apis dorsata), and Africanized honeybees (Apis mellifera scutellata and A. m. capensis). If varroa mite were to establish in Australia its impact has been predicted to be devastating to the Australian apiculture industry. (2) However, the im- pact would not be limited to the apiculture industry as many horticultural, seed grain, and pastoral indus- tries would also be adversely affected due to reduced pollination of their plants. (3) The economic impact of V. destructor in North America following its establishment in the 1980s is estimated to range from US$0.6 to 14.6 billion. (4−7) In Australia, the pollination benefits that would be lost following varroa mite introduction are estimated to be A$27.5 million for a group of 25 horticultural and seed grain industries. (3) The risk to Australia of exotic bee species en- tering via cargo movements has been highlighted by 1961 0272-4332/11/0100-1961$22.00/1 C  2011 Society for Risk Analysis