Non-indigenous insect species in Israel and adjacent areas

Non-indigenous species cause great damage worldwide. Non-indigenous insects are known as harmful in many regions, but few comprehensive works have investigated non-indigenous insects as a group. We compiled a comprehensive database of established non-indigenous (ENI) insects in Israel and adjacent regions to investigate how they arrived, their biological characteristics, and the attributes of areas they invade. Of 218 species of ENI insects in this region, 124 are widespread. Most species came as stowaways, but 38 were brought intentionally for biological control. Most ENI insects in this region are in the Coleoptera, Diptera, Hymenoptera, Lepidoptera, and Homoptera. Species from various orders differ in their tendency to be localized or widespread, and in biogeographic origins. The distribution of species among orders differs between native and ENI insects. The Coastal Plain houses the most ENI insect species and the Negev and Judean deserts the fewest. Most ENI insects spread from the Coastal Plain to other regions. Absence of roads, settlements and presence of nature reserves are negatively correlated with occurrence of ENI species. Seventy-nine species are categorized as pests that damage produce, merchandise, forestry, etc. Despite a general dearth of knowledge on impacts of ENI insects on natural systems, 42 species are known to feed on native plants, some of conservation concern. Biological control agents are usually more limited in their distribution than other ENI insects. Further research, legislation, and enforcement are required to minimize effects of these species on agriculture and natural habitats.