Using sighting records to declare eradication of an invasive species

Abstract

1. A major challenge for eradication managers is deciding when a programme can be deemed successful. Regan et al. (2006) were the first to pose this problem within a decision theory framework, minimizing the net expected cost of the decision. The optimal time to declare eradication was based on the number of consecutive surveys in which the species was not found ('absent surveys'). Their formulation used estimates of detectability and persistence - parameters that are often difficult to estimate - to calculate the probability that the invasive species is still present. 2. Here we use a similar decision-making framework but instead predict presence based on the pattern of sightings, using a m..