Managing the intentional introduction of nonnative species

This chapter illustrates themanagement for the intentional introduction of nonnative species, based on the case of introducing nonnative oysters on the US East Coast, from two institutional structures. First, we consider the public management context, where a government agency makes all decisions regarding introduction and management of the introduced species, and private parties have shared access to the resource. Second, we consider a private management case, where a private firm makes all decisions regarding introduction and management of the introduced species, subject to a set of incentives and constraints developed by the government agency. The public management problem is analyzed using a spatially explicit, dynamic multi-agent computer model that simulates the growth, spread and harvest of oysters over time. We find that technology-based control in the form of introducing non-reproductive triploid oysters is an effective means of controlling the risk of invasion. In contrast, our results suggest it is much less effective to use best management practice of introducing reproductively-capable oysters in relatively isolated areas, with low connectivity to the rest of the estuary. The private management problem is analyzed using a principal-agent model, whereby a regulating government agency acts as principal, and firms proposing to introduce nonnative species act as agents. The framework determines tradeoffs between the potential social benefit of an intentional introduction versus the likelihood that the species becomes invasive and the potential harm that might result. The model is used to assess how the principle can design various policies that can provide incentives and constraints to solve the adverse selection and moral hazard problems on the part of agents. The result shows that if the agent underestimates the challenge of controlling the risks of invasion, they are more likely to participate and may be subject to an adverse selection problem. The extant literature has found that the invasive species problem is a "weakest link" problem, whereby attempts to control invasions are only as effective as the weakest link in a chain of actions. Our results suggest that ex ante incentives to avoid invasion can result in a selection for "weak links".