Fear not, Colorado: ‘Murder hornets’ shouldn’t be your concern

In a year that’s been besieged by epic wildfires and a global pandemic, 2020 is playing out with its share of alarming headlines. In the past few weeks, a new contender for concern has landed headlines above the fold — the so-called “murder hornets.”

The Asian giant hornet (Vespa mandarinia) is native to East and South Asia, so alarm bells rang when scientists spotted the hornets last fall in British Columbia. In December, the hornet was spotted in Washington state, the first time on U.S. soil, which eventually led to viral media coverage about its inevitable spread through the country. So how concerned should Colorado be? Not very, says Colorado State University entomologist Whitney Cranshaw in the College of Agricultural Sciences.

Unlikely impact in Colorado

“[The hornet] is a woodland species adapted to moist, low elevation sites, like the area where it presently occurs, not like anywhere in Colorado,” Cranshaw said. “This is not an insect that hitchhikes well so for it to spread, it’s on its own. And between eastern Washington and western Colorado there are thousands of geographic barriers that it would likely not be able to cross. I cannot see any scenario on how it could get to Colorado on its own. Not to mention it likely would not be well adapted to the area, and likely would not establish, if someone were to carry it here.”

The fear stoked by the unprecedented presence of V. mandarinia isn’t totally unfounded. The nickname for the species derives for its size, venom and aggressiveness. The average hornet reaches a body length of about 2 inches, a wingspan of 3 inches and wields a stinger a quarter-inch long with the potential to inject large amounts of powerful venom. Stings have been equated to the feeling of hot metal piercing the skin.

Effects on honey bee population

While that sounds nightmarish in itself, many are worried about the impact an Asian giant hornet invasion could have on the nation’s honey bee population, which Cranshaw also feels has been blown out of proportion.

“This is a generalist predator and honey bees are only one of many kinds of insects this insect hunts,” Cranshaw said. “Whether this would be any worse than some of the hunting wasps established in North America that take out honey bees or western yellowjackets that not uncommonly take out weak honey bee colonies, is to be seen. I am not saying that this is not a species that can be detrimental to honey bees, but let’s keep it in proper perspective, as, if it permanently establishes, it will fall far down the line among the many recently established pests that pose problems to honey bees in North America.”

So, Colorado, give a sigh of relief and cautiously cross this off of your list things to worry about in 2020. As for the name “murder hornet,” Cranshaw has a thought or two about that as well.

“The name is just silly and needlessly inflammatory — it’s a predator, it eats other insects,” Cranshaw said. “We have three wasp families — Sphecidae, Crabronidae, and Pompilidae — that are very well represented in most any yard or garden in the state which are generally referred to by the far more benign term ‘hunting wasps.’ These insects paralyze their prey, haul the paralyzed insect to some nest, lay an egg on it and have a larval stage that slowly consumes the live, paralyzed insect. Should we call these the ‘kidnap and slowly butcher’ wasps?”