Bruce Beehler is a naturalist and author of 12 books, including “Natural Encounters” and “Birds of Maryland, Delaware, and the District of Columbia.”
Grab your suitcase. Empty your bank account. Fuel up the car. The murder hornets are coming!
Last week, the news media regaled us with eye-catching accounts of a hornet incursion in Blaine, Wash., where the state department of agriculture deployed its troops against a big tree-hole nest of the insects — including nearly 200 queens, who might have otherwise released their evil spawn on an unsuspecting nation. “The mission began before dawn,” as The Post’s correspondent described the operation, which involved “scientists covered head to toe in thick white protective gear.” A local said the basketball-size nest made her think of aliens: “It looked like it was from another world.”
In fact, Asian giant hornets — as they’re actually called — are very much of this planet. Also nicknamed “yak-killer hornet” and “giant sparrow bee,” this species, which ranges from Sri Lanka to Japan, somehow found its way to the west coast of North America, first reported in 2019 in British Columbia. The hornets probably stowed away in a shipload of merchandise.
People in the United States are alarmed about the arrival of this fierce-looking creature for two reasons. First, its stinger packs a wallop that one scientist described as akin to having a red-hot thumbtack driven into one’s flesh. Second, and more worrisome, is that the hornet is known to be an aggressive predator of the common honeybee — a species that pollinates many of our economically important crops and orchards.
Exotic invasive species have become a familiar feature of life in the United States — some of them posing serious challenges to federal and state authorities.
A prime example is the chestnut blight from East Asia, which killed as many as 4 billion American chestnut trees in the early 20th century. Because of that exotic invasive fungus, the once-beloved American chestnut is absent from our woodlands.
Then there’s the zebra mussel (introduced via ship’s ballast water from Russia), which has caused more than $5 billion of damage to waterways in and around the Great Lakes. And the silver carp (brought from China) now infests rivers of the Mississippi drainage. Who has not seen videos of these fish rocketing crazily out of the water in the hundreds, frightened by a passing motorboat? Burgeoning carp populations are wrecking aquatic ecosystems in our heartland.
And don’t forget the SARS-CoV-2, virus, the source of the current global pandemic — the latest in a long line of migrant microbes, some destructive, others not. (Some scientists believe that studying invasive species might help us to combat the spread of diseases such as covid-19.)
Yet there are also plenty of invasive species that, while they might have a certain nuisance value, don’t wreak widespread destruction. The ubiquitous house sparrow is one; so, too, is the butterfly bush, which provides food for countless insects in the United States.
To ecologists, each new introduction of an exotic species to North America is an uncontrolled biological experiment with unknown long-term results. As far as murder hornets are concerned, agricultural authorities probably won’t be able to extinguish them all. Getting rid of the two established populations in British Columbia and Washington state would be like successfully killing every mosquito in your backyard on a summer’s evening with a fly swatter.
Is there reason for alarm? Yes, but probably not because of any direct threat to humans. There are lots of venomous bugs in the United States, and these new arrivals don’t appear to be unduly aggressive, unlike the Africanized honeybees — yep, “killer bees” — that caused such consternation in the mid-1980s in the Deep South. More worrisome is the species’ possible impact on the honeybee-reliant commercial pollination systems in agriculture, which could potentially cause billions of dollars of economic harm. Think of the Mediterranean fruit fly’s depredations in California, Florida and Texas.
So how well will the Asian giant hornet adapt to the varied environments in the United States? It apparently evolved in humid forested environments. Recent ecological modeling indicates the hornet might remain confined to the Pacific Northwest over the next two decades.
The only other true hornet in North America is another introduced species, the European hornet. This slightly smaller species is now widespread in the United States, and most people aren’t even aware of its existence. It’s also known to be a predator of honeybees but seems to have had relatively little impact on their numbers in the United States. This gives us a reason not to worry about its larger relative.
Here’s the thing. There are more than 91,000 species of insects in the United States. The Asian giant hornet will become one more member of that huge group of species. Like so many introduced exotic species, it probably will have no serious effects, other than scaring people who are already frightened of creepy crawlies. A sting from one, in most cases, will be little more than a painful badge of courage. We have no evidence at this stage that the species will become widespread. It might just become a curiosity confined to the dark conifer forests of the Pacific Northwest — something like Sasquatch.
Hysteria over a potentially invasive species is understandable, but it’s not a basis for good policy. Most invasive species, once established, can’t be eradicated. We need to focus all our energy on containing those exotic species that pose the most threat. Murder hornets aren’t one of them.