Simple Environmental Solutions Versus Human Behavior: New Zealand Mudsnails
In order to reinforce the importance of integrating social and biophysical sciences to solve environmental problems, it is sometimes useful to tilt at straw men. Take the case of the New Zealand mudsnail, and this paper that purports a solution: Simple Control Method to Limit the Spread of the New Zealand Mudsnail Potamopyrgus antipodarum. Awesome, let's go home.
But wait...some facts about the NZ mudsnail. Since first being discovered in 1987 in the US, the NZ mudsnail has spread throughout many Western watersheds. It has the potential to out-compete the macro-invertebrates that support native and game fish populations, such as the valuable trout. Most importantly for this blog post, one of the primary vectors for spread is on the boots and waders of anglers. Since they are really tiny, it is difficult for anglers to even know they are spreading them.
But don't worry. According to the paper, all you have to do is freeze them. For a few hours. After you've come back from fishing, and you can put your boots in your empty freezer. Watch out for the chilled beer glasses. Alternatively, maybe you should just buy another pair of boots and waders to use in infected streams. Since fishing gear is cheap. And we all know how easy it is to identify a tiny mudsnail in an unmarked, remote Western stream and choose the right waders. But the technical solutions are simple indeed.
Sorry if you're now smothered by sarcasm. However, anybody who really studies environmental problems will instantly recognize the incredibly difficult and complex (don't make me say "wicked") collective-action problem created by the NZ mudsnail. Controlling the spread of the NZ mudsnail and similar invasive species requires cooperation from all the individuals involved in the spread. The benefits of each individual's control efforts are enjoyed by others (non-excludable in econ talk), but the costs are private. Therefore individuals have an incentive to free-ride on the efforts of others. But if even one individual decides to avoid the costs of control efforts, they remain a potential vector for spread.
Although I have not seen any actual studies (please point them out if you know one) that looks at how many anglers are even aware of the NZ mudsnail, know the control strategies and at least say they're willing to cooperate, I guarantee it is far less than universal. Hence there will always be a human behavioral reservoir for the spread of the NZ mudsnail. The story of the NZ mudsnail requires the joint analysis of human and ecological systems--simple technical solutions are very often complex in social systems. However, I doubt the NZ mudsnail will have a happy ending as an invasive species. The mostly voluntary control efforts may slow the spread, but it is here to stay.