David Finnoff

An ounce of prevention or a pound of cure: bioeconomic risk analysis of invasive species

Numbers of non–indigenous species—species introduced from elsewhere—are increasing rapidly worldwide, causing both environmental and economic damage. Rigorous quantitative risk–analysis frameworks, however, for invasive species are lacking. We need to evaluate the risks posed by invasive species and quantify the relative merits of different management strategies (e.g. allocation of resources between prevention and control). We present a quantitative bioeconomic modelling framework to analyse risks from non–indigenous species to economic activity and the environment. The model identifies the optimal allocation of resources to prevention versus control, acceptable invasion risks and consequences of invasion to optimal investments (e.g. labour and capital). We apply the model to zebra mussels (Dreissena polymorpha), and show that society could benefit by spending up to US

Risk assessment for invasive species produces net bioeconomic benefits

324 000 year−1 to prevent invasions into a single lake with a power plant. By contrast, the US Fish and Wildlife Service spent US

Protecting an Endangered Species While Harvesting Its Prey in a General Equilibrium Ecosystem Model

825 000 in 2001 to manage all aquatic invaders in all US lakes. Thus, greater investment in prevention is warranted.

Ship-borne Nonindigenous Species Diminish Great Lakes Ecosystem Services

International commerce in live organisms presents a policy challenge for trade globalization; sales of live organisms create wealth, but some nonindigenous species cause harm. To reduce damage, some countries have implemented species screening to limit the introduction of damaging species. Adoption of new risk assessment (RA) technologies has been slowed, however, by concerns that RA accuracy remains insufficient to produce positive net economic benefits. This concern arises because only a small proportion of all introduced species escape, spread, and cause harm (i.e., become invasive), so a RA will exclude many noninvasive species (which provide a net economic benefit) for every invasive species correctly identified. Here, we develop a simple cost:benefit bioeconomic framework to quantify the net benefits from applying species prescreening. Because invasive species are rarely eradicated, and their damages must therefore be borne for long periods, we have projected the value of RA over a suitable range of policy time horizons (10–500 years). We apply the model to the Australian plant quarantine program and show that this RA program produces positive net economic benefits over the range of reasonable assumptions. Because we use low estimates of the financial damage caused by invasive species and high estimates of the value of species in the ornamental trade, our results underestimate the net benefit of the Australian plant quarantine program. In addition, because plants have relatively low rates of invasion, applying screening protocols to animals would likely demonstrate even greater benefits.

Future declines of the binational Laurentian Great Lakes fisheries: the importance of environmental and cultural change

Because endangered species are in predator/prey, competitive, and other relationships with many species who share their habitat, efficient conservation requires simultaneously considering the needs of many species. Understanding ecological relationships and understanding how human activity affects these other species and indirectly affects endangered species are important to know when forming endangered species policies. We offer an integrated ecological/economic model that tracks both ecological relationships and human activities. The model is applied to an Alaskan marine ecosystem in which fish are harvested and Steller sea lions are endangered. Results illustrate the tradeoff between harvested fish and endangered sea lions. (JEL Q22)

Merging Economics and Epidemiology to Improve the Prediction and Management of Infectious Disease

AbstractWe used structured expert judgment and economic analysis to quantify annual impacts on ecosystem services in the Great Lakes, North America of nonindigenous aquatic species introduced by ocean-going ships. For the US waters, median damages aggregated across multiple ecosystem services were 138 million per year, and there is a 5% chance that for sportfishing alone losses exceeded 800 million annually. Plausible scenarios of future damages in the US waters alone were similar in magnitude to the binational benefits of ocean-going shipping in the Great Lakes, suggesting more serious consideration is warranted for policy options to reduce the risk of future invasions via the St. Lawrence Seaway.

A Bioeconomic Model of Cattle Stocking on Rangeland Threatened by Invasive Plants and Nitrogen Deposition

It is increasingly clear that future long-term environmental challenges (eg climate change) are being driven by economic and cultural choices, as well as by physical and biological mechanisms. We looked at the extent to which these apply to potential future changes in fisheries in the Laurentian Great Lakes. These fisheries rank among the most valuable freshwater fisheries in the world, but have declined markedly in recent decades. To investigate how these fisheries might develop in the future, we elicited projections from experts in fisheries and related fields. Experts provided assessments on variables relating to US and Canadian commercial (pounds landed) and sport (participation and expenditures) fisheries for the years 2006 and 2025. We measured each experts ability to quantify their uncertainty, producing performance-weighted combinations of expert estimates. All experts expected commercial fisheries to decline from 2006 to 2025, with greater declines in the US (25%) than in Canada (9%). Expectations for sport fishing differed more between lakes and less between countries, with median expected declines ranging from 1% to 13%. Experts attributed expected declines primarily to changes in economic market demands and shifts in societal interests. Increased attention to social and economic trends could aid Laurentian Great Lakes fishery policy and management.

Economic optimization of a global strategy to address the pandemic threat

Mathematical epidemiology, one of the oldest and richest areas in mathematical biology, has significantly enhanced our understanding of how pathogens emerge, evolve, and spread. Classical epidemiological models, the standard for predicting and managing the spread of infectious disease, assume that contacts between susceptible and infectious individuals depend on their relative frequency in the population. The behavioral factors that underpin contact rates are not generally addressed. There is, however, an emerging a class of models that addresses the feedbacks between infectious disease dynamics and the behavioral decisions driving host contact. Referred to as “economic epidemiology” or “epidemiological economics,” the approach explores the determinants of decisions about the number and type of contacts made by individuals, using insights and methods from economics. We show how the approach has the potential both to improve predictions of the course of infectious disease, and to support development of novel approaches to infectious disease management.

Bioeconomics of invasive species: using real options theory to integrate ecology, economics, and risk management

Across western North America, invasive plant species and elevated levels of nitrogen are threatening the productivity of rangelands. A bioeconomic model of stocking cattle on these rangelands is used to show that optimal stocking depends on the competition between native grasses and the invaders. However, nitrogen deposition is important in determining the ultimate rangeland species composition. Endogenous changes in plant successional thresholds are due to the interplay of nitrogen deposition and stocking practices. Nonoptimal overstocking can create ecosystem niches for invaders where they would not have occurred at lower stocking rates, although what constitutes overstocking depends on the nitrogen levels.

Invasive Species and Delaying the Inevitable: Results from a Pilot Valuation Experiment

Significance Emerging pandemics are increasing in frequency, threatening global health and economic growth. Global strategies to thwart pandemics can be classed as adaptive (reducing impact after a disease emerges) or mitigation (reducing the causes of pandemics). Our economic analysis shows that the optimal time to implement a globally coordinated adaptive policy is within 27 y and that given geopolitical challenges around pandemic control, these should be implemented urgently. Furthermore, we find that mitigation policies, those aimed at reducing the likelihood of an emerging disease originating, are more cost effective, saving between