There have been warning signsfor years about plummeting insect populations worldwide, but the extent of the potentially “catastrophic” crisis had not been well-understood — until now.

The first global scientific review of insect population decline was published this week in the journal Biological Conservation and the findings are “shocking,” its authors said.

More than 40 percent of insect species are dwindling globally and a third of species are endangered, concluded the peer-reviewed study, which analyzed 73 historical reports on insect population declines.

Chillingly, the total mass of insects is falling by 2.5 percent annually, the review’s authors said. If the decline continues at this rate, insects could be wiped off the face of the Earth within a century.

“It is very rapid. In 10 years you will have a quarter less, in 50 years only half left and in 100 years you will have none,” study co-author Francisco Sánchez-Bayo, an environmental biologist at the University of Sydney, Australia, told The Guardian.

“If insect species losses cannot be halted, this will have catastrophic consequences for both the planet’s ecosystems and for the survival of mankind,” Sánchez-Bayo added.