Invasive Species Management

We study the problem of precluding biological invasions caused by ships transporting internationally traded goods in containers between different regions of the world. Using the long run expected net cost of inspections as the apposite managerial objective, we address the(LRENC) following important question: Given that inspection is a cyclical activity, is the lower whenLRENC a port manager’s inspector inspects cargo upon the arrival of a specified number of containers (container policy) or is this lower when this inspector inspects cargo at fixed points in timeLRENC (temporal policy)? We construct a queuing theoretic model and show that in an inspection cycle, irrespective of whether the inspection policy choice is made on the basis of an explicit optimization exercise or on the basis of rules of thumb, the container policy is superior to the temporal policy because the container policy results in lower from inspection activities. LREN