Quantitative risk-assessment for the potential alien pest insects in Japan using a GIS-based web database of the world pest insects

Background/Question/Methods

The national quarantine system in Japan has been very strict and extensive. All cargoes entering Japan are inspected, and any suspicious consignment is subject to admonitory cessation of import, restriction, exhaustive inspection, or clearance. Recently, partner countries and international organizations such as WTO have requested Japan to discontinue the superfluously strict regulations and to relax quarantine based on scientific risk-assessment in order to secure international trade currency. Thus, to rationalize the quarantine process, it is our urgent task to draw up a black list of potential invasive species that may give serious damages on agriculture in Japan based on scientific knowledge. However, how can we evaluate the potential risk of a pest species that has NOT yet invaded Japan? Nevertheless, invasive insect pests, particularly those of agricultural importance, have been inventoried by several international organizations, and this information can be retrieved via the internet. We can now easily access information on non-native species from around the world; however, little attempt has been made to scientifically quantify the risk of potentially invasive insects and to utilize this information for local risk-assessment in actual quarantine administration.

Results/Conclusions

In this study, we exhaustively collected information on invasive insect pests in the world from various worldwide databases, and ca 5,000 species were indexed in our intra-network web application using a GIS database (a geographic information system-related database). Of the 5,000 species catalogued we initially focused on 500 species as candidates of primary importance. We obtained comprehensive details on the native and invasive distributions of these species and also on their basic biological characteristics. The invasion probabilities of these 500 species were calculated using Maxent, one of the statistical tools for predicting species distribution. The invasion probabilities were further weighted with the annual yield of agricultural products related to the focal insect. The total sum of the products of invasion probability and the value of all agricultural products related to the insect will be a used to predict the potential risk of a specific species in Japan. Using this procedure, we evaluated the risk for all 500 species.