Praying mantises all over the world hunt and eat birds

New research suggests the long-armed insects also hunt and eat birds. And their taste for the mammals isn't geographically isolated, but present across the globe -- wherever mantises are found.

A survey of the scientific literature on mantis feeding phenomena proves at least twelve mantis species, representing nine genera, have been observed hunting and feeding on small birds. Researchers published their analysis this week in the Wilson Journal of Ornithology.

Researchers reviewed documentation of 147 bird-eating incidents among mantis species. The phenomenon has been observed in 13 different countries, including all continents except Antarctica.

"The fact that eating of birds is so widespread in praying mantises, both taxonomically as well as geographically speaking, is a spectacular discovery," Martin Nyffeler, a biologist at the University of Basel in Switzerland, said in a news release.

Despite the apparent widespread nature of the feeding behavior, 70 percent of the reviewed incidents occurred in the United States. The latest analysis suggests hummingbirds -- particularly the ruby-throated hummingbird -- are the most frequent victims of mantises, which lie in wait near hummingbird feeders or nectar-rich flowers.

In some instances, researchers warn this feeding behavior may be unnatural. In the 20th century, large alien mantis species, including Mantis religiosa and Tenodera sinensis, were introduced to habitats in the United States for pest-control purposes. These invasive species could be a potential threat to vulnerable hummingbird species, as well as small passerine birds.

"Our study shows the threat mantises pose to some bird populations," said Nyffeler. "Thus, great caution is advised when releasing mantises for pest control."