If you think about invasive species, insects probably aren’t your first thought. However, invasive bugs like locusts and mosquitoes can cause more than enough damage to change that line of thinking.
For the past year and a half, biologists from several American universities teamed up with entomologists from around the world to identify invasive insect species that should be eradicated. The invasive bugs on their list cause an estimated $57 billion of damage annually, the team wrote in the journal Science.
“I’m not advocating biological warfare,” said study author Wayne Linklater from the University of Auckland, New Zealand. “I’m just advocating for effective invasive-species management.”
This bug originated in Asia and first appeared in Pennsylvania in 2014. This invasive species can fly quickly, doubling its population in just four months. While the bug is only about half an inch long and doesn’t bite humans, it does threaten to destroy $18 billion worth of fruit crops every year. It’s so dangerous that US federal officials consider it a threat.
Spongy moths are invasive bugs that breed really quickly. They first appeared in France and recently spread to Belgium, Luxembourg, Germany, Italy, Poland, and the Netherlands. The invasive species also has one of the fastest doubling times on Earth—it can reproduce four generations in just over a month. Spongy moths eat vast amounts of crops, including more than 40 types of fruit trees. They cost European farmers around $1.7 billion every year.
Southern Pine Beetle
These invasive bugs have a track record of destroying pine forests. When the invasive species first arrived in Alabama’s southern region, researchers expected it to spread slowly through Georgia and North Carolina. Instead, its population exploded due to milder winters (which don’t kill as many bugs) and fewer trees dying because of drought or disease.
Brown Marmorated Stink Bug
The brown marmorated stink bug can destroy hundreds of fruits and vegetables in a single feeding. This invasive species has destroyed a third of US apple crops since it arrived about 20 years ago. Farmers have been forced to dump or compost 14 million bushels of apples due to stink bugs eating the fruit, which costs farmers $37 million.
Emerald Ash Borer
The emerald ash borer looks like a beautiful jewel bug, but it’s really a destructive invasive species that can kill ash trees in just two years by eating its bark and laying eggs inside the phloem. This invasive species has destroyed more than 60 million ash trees. The invasive bugs cost farmers up to $25 billion each year.
Despite its small size, this fuzzy bean-looking bug is one of the most invasive bugs in the world. The Khapra beetle eats the same crops as the invasive locust, but it can also eat stored food like cereal grains. Cargo ships accidentally spread the invasive species all over the world by carrying infested grain.