Economic impacts of forest pests: a case study of spruce budworm outbreaks and control in New Brunswick, Canada

We investigated the potential economic impacts of future spruce budworm (SBW) (Choristoneura fumiferana (Clemens)) outbreaks on 2.8 million hectares of Crown forest land in New Brunswick by coupling an advanced Spruce Budworm Decision Support System (SBW DSS) model with a dynamic computable general equilibrium model. A total of 16 alternative scenarios were evaluated, including two SBW outbreak severities (moderate versus severe), four SBW control program levels (protecting 0%, 10%, 20%, and 40% of susceptible Crown land forest area), and two pest management strategies ("without" versus "with" replanning harvest scheduling and salvage). The "without" replanning harvest scheduling and salvage strategy findings indicated that, under uncontrolled moderate and severe SBW outbreaks, total output in the New Brunswick economy over the 2012-2041 period would decline in present-value terms by CDN$3.3 billion and $4.7 billion, respectively. SBW control via aerial spraying was shown to reduce the negative impacts on output by up to 66% when protecting 40% of susceptible area. Combining SBW control with replanning harvest scheduling and salvage strategy under moderate and severe outbreaks would reduce the negative impacts on output by a further 1%-18% depending on the level of control implemented. These findings can help forest managers assess the direct and indirect economic effects of forest pest disturbances on regional economies and can also be used together with other sustainable forest management indicators to help broaden the scope of SBW and other forest pest management decision-making.