Analysis of insect pests identified to species that were intercepted at Chinese ports of entry

Interception data of insects collected at quarantine borders across China were crosschecked with incursion data from 2003 to 2016. In total, 83,983 insect interceptions were recorded across quarantine borders, involving 1,458 insect species. The species interception index at the family level was calculated to make each insect family comparable. Among the intercepted families, eight families that harm woody plants were intercepted at a high frequency, of which Noctuidae was the most intercepted family. In contrast, seventeen families that harm non-woody plants had a high interception frequency, of which the Silvanidae had the highest species interception frequency. Among the 1,458 intercepted insect species, 147 species were included in a list of quarantine insects in China. In terms of insect species, thirteen species had a high interception frequency (intercepted > 100 times or the cumulative yearly interception >= 10 years), accounting for 90.1% of the total interceptions. Among these 13 species, ten species have become established in mainland China, with eight species specifically harmful to woody plants. Looking at the extent of insect pest interceptions, corresponding control measures should be initiated to minimize impacts to natural forests. These results show that border quarantine surveys can help identify and target control measures against invasive alien species. Still, the current quarantine system needs further improvement to successfully prevent alien species from crossing the border and spreading in natural areas.