Abstract
Humans have translocated thousands of species, either intentionally or
not, from their native ranges to non-native ones, with many established
(naturalized) and some now invasive. We report here a global database on
the distributions of naturalized alien insects. Currently, 7,741
naturalized alien insect species have been reported from 222 regions, of
which 47 species were reported over all six continents, 103 species over
five continents, and 208 species over four continents. Naturalized alien
insects are taxonomically diverse in all six continents, predominantly
occurring in agroecosystems, as well as forests and grasslands. North
America has accumulated the greatest number of naturalized alien insect
species, while South America has the lowest number. Asia donated the
greatest number of its native insect species to other continents,
especially to North America and Europe. The global patterns of
naturalized alien insects are correlated with transcontinental trade and
the number of local scientists who study insect invasions. Most
naturalized alien insects have been introduced to multiple continents,
further facilitating the expansion of introduced populations through
bridgehead effects. Understanding the global exchange and accumulation
of alien insects helps the development of an early warning and
monitoring system for insect invasions.