Risk and pathway assessment for the introduction of exotic insects and pathogens that could affect Hawai'i's native forests

Abstract

The unmitigated risk potential of the introduction of exotic insects and pathogens to Hawai'i was evaluated for its impact on native plants, specifically Acacia koa, Cibotium spp., Dicranopteris linearis, Diospyros sandwicensis, Dodonaea viscosa, Erythrina sandwicensis, Leptecophylla tameiameiae, Metrosideros polymorpha, Myoporum sandwicense, Pandanus tectorius, Scaevola spp., Sophora chrysophylla, and Vaccinium spp. Assessments were made by estimating the likelihood and consequences of introduction of representative insects and pathogens of concern. Likely pathways of introduction were assessed. Twenty-four individual pest risk assessments were prepared, 12 dealing with insects and 12 with pathogens. The selected organisms were representative examples of insects and pathogens found on foliage, on the bark, in the bark, and in the roots and wood of the native hosts of interest—or closely related host species—in other parts of the world. Six priority findings resulted from the analysis: Inspection alone is not 100 percent effective in preventing introductions. The primary sources of introductions are the mainland the United States and Asia-Pacific. There is a strong need to make visitors aware that they are a significant potential source of unwanted introductions. Plant materials, especially live plants, are by far the most important source of pest problems for Hawai'i. The solid wood packing material pathway needs more scrutiny. Many pests using this pathway have already become established in Hawai'i, and many more are on the list of potentials. Because Hawai'i Department of Forestry can only inspect wood packing material that is associated with agricultural commodities, and because wood packing material is not necessarily specified as associated with cargo, this is potentially a pathway that is being insufficiently inspected and regulated. The interstate movement of certain plant materials from Hawai‘i to the mainland is restricted without treatment and certification. Similar restrictions on interstate movement into Hawai‘i are not in place. For the most part, Animal Plant and Health Inspection Service regulations do not discriminate between the mainland and islands of Hawai'i as far as potential threats. This includes some organisms that are native or commonly found on the mainland. Numerous other observations, both specific and general, are included in the pest risk assessment concerning detection surveys, regulations, and public education/public awareness of the dangers of introduced pests and pathogens.View or download the Appendix (3.2 MB)