Thrips: Thysanoptera

Physical characteristics: Western flower thrips are yellow to dark brown and measure about 0.04 inches (1 millimeter) in length.

Geographic range: Originally from the western United States, they now live throughout the temperate parts of North and South America, Europe, Africa, Asia, Australia, and New Zealand.

Habitat: They live on the flowers and leaves of many different kinds of plants.

Diet: They eat pollen as well as new flower and leaf tissues. They will occasionally prey on mites.

Behavior and reproduction: Western flower thrips fly up to one hundred yards at a time when their food plants are disturbed. Their distribution across oceans, however, is a result of hitchhiking on plants sold around the world. Males will compete with other males for territory on a leaf, but only when the population density of thrips is low.

Western flower thrips fly up to one hundred yards at a time when their food plants are disturbed. Their distribution across oceans, however, is a result of hitchhiking on plants sold around the world. (Illustration by John Megahan. Reproduced by permission.)

Thrips reproduce by mating, with males developing from unfertilized eggs.

Western flower thrips and people: The western flower thrip is one of the most important pests in the world. Their feeding activities cause serious damage to flower crops, tomatoes, capsicums and cucumbers, as well as stone fruits and table grapes. They also infect many plants with disease as they feed.

Conservation status: This species is considered a pest. It is not listed as endangered or threatened. ∎