Pine shoot beetle, Tomicus piniperda (Linnaeus): analysis of regulatory options for Canada.
The pine shoot beetle (PSB), Tomicus piniperda, an invasive forest species introduced to Canada in the late 1980's or early 1990's, is a federally regulated species. Since 1994 a federal quarantine has been imposed to regulate the movement of at-risk pine commodities, including logs and firewood, and nursery stock. Over the past 20 years, the pine shoot beetle has spread northward from its initial areas of detection and quarantine around the US-Canada border in Ontario and Quebec. Initial risk assessments raised concern that the beetle would spread from the existing areas of known occupation and damage valuable pine forests that are important for the forest sector across Canada. However, after 20 years of experience, little evidence has surfaced that the PSB has caused significant damage to native pine stands. The purpose of this study was to evaluate the net benefits of current efforts to slow the spread of the pine shoot beetle from its current range of southern Ontario and Quebec. This study emulated a study conducted by the United States Department of Agriculture in 2015. We compared the expected economic losses from damaged pine trees under the current efforts to slow the spread of T. piniperda with the potential damages without regulations. The benefit of regulation is to push damage further into the future, assuming that the value of a loss in the future is less than the same loss incurred today. We compared the value of delayed damage to the on-going costs of regulation in the form of inspections and permitting the movement of regulated materials. We focussed on all merchantable pine forests in eastern Canada, i.e. east of Manitoba, regardless of geographical location. However, our study did not consider non-timber values such as carbon, biodiversity, or recreation nor did we try to account for damage to private residential property. These values may be locally important but, we found no evidence to suggest they were significant and so were not addressed in the analysis. The findings of the study indicate that under conservative assumptions, it is very unlikely that the current regulatory program is beneficial. Assuming conservatively low cost estimates of regulation and high estimates of area that might be impacted by the PSB, we found only a 7.5%-17.4% chance that the program is generating a net benefit, depending on spread rates. Even with increased effective regulation (i.e. slower spread rate under regulation), there is only a small chance that the program might produce a net benefit. Break-even analysis indicated that a much higher mortality rate than supported by current scientific literature and expert opinion would be required for the program to pay for itself. The results suggest there is likely little downside risk to deregulating the pine shoot beetle. The very low estimated mortality caused by Tomicus piniperda on native pine species in Canada underpins the analysis. A much higher mortality rate than is currently documented in available information would have to occur for the program to be an efficient use of public funds.