Developing and maintaining national plant pest lists help fulfill international obligations for trading countries, and also provides a foundation for national biosecurity systems. However, national lists remain rare, and analyses that might help guide biosecurity policy are few. We compiled and analysed a national plant pest list for Bhutan, a relatively small but agriculturally diverse country.
Key features of the database included: i) comprehensive referencing of records to help knowledge retention, an important challenge in most countries; ii) categorising taxonomic uncertainty for each pest record; and iii) categorising each pest according to their current importance.
Analyses revealed several challenges that are likely to be common to most countries. Confidence in species identifications reduced dramatically since the initial aid-funded, pest-documentation phase (1985-8). Furthermore, 38% of species identified by 1988 had subsequent name changes, highlighting the need for continued effort and expertise to maintain lists. Most recent records lacked voucher specimens, and those for older material are mostly located internationally, making revisions challenging.
The database did provide many benefits. All damaging pests (14% of 604 species) were already present in neighbouring India, which is also the major trading partner, and 73% occur beyond Asia, suggesting a regional approach to biosecurity would greatly benefit Bhutan. Very few new damaging pests have entered Bhutan since 1988, suggesting risks are manageable.
National pest lists are critical, but to be of greatest value they need to focus on damaging pests. For most countries their development, maintenance and use will require ongoing regional and global co-operation to overcome taxonomic impediments, and to maximise their benefits in terms of facilitating trade and guiding domestic biosecurity activities.