Jeezum! What Is The Flipping Deal With All These Fetching Box Elder Bugs?

My recent rant on Winter seems only to have angered her more (and isn’t that just like a stalker? I am telling you, you cannot reason with them!) But I’ve been teased by Spring, and I can’t get Spring-like thoughts out of my mind. I mentioned how lovely the weather was Saturday, and I went on about biking and Meadowlarks and such. But the sign of Spring that everyone in my family noticed was something else.

When I moved to Utah in the mid-nineties, there were 4 things I encountered during my first year that I did not expect. You probably think I’m going to list some things about religion, or the liquor laws or slot canyons some such, but you’re wrong. I knew about all those things long before I moved here. No, the first surprise was thermal inversions, which I’ve already blogged about.

All About Cursing In Utah

The second surprise was the whole, weird Alternative Cursing Lexicon here in Utah. Many people raised in Utah seem just a bit more averse than folks in other parts of the US to swearing or taking the Lord’s name in vain casually. That wasn’t a huge surprise, but what was a surprise was that in place of “regular” cursing”, a whole strange alternative lexicon of “pseudo-curses” has apparently evolved over time. Examples include “Fetch”, “Flip”, “Gol!”, “Jeezum”, “Oh My Heck!”, “Bullcrap”, and “The F-Bomb”, among others*. And native-Utahns will use-and even conjugate- these words just like we- er, pardon me- just like some people use “regular” curse words, such as in “Fetch! I broke my flippin’ derailleur!”

*Awesome Wife’s all-time favorite = “Oh For Tender!”

The third surprise was Fry Sauce, which I won’t get into, because if you live in Utah you already know all about it, and if you don’t, it’s not really worth explaining.

Personal Trivia Factoid: Over the past decade I have come to love fry sauce. I am the only non-native Utahn I know who puts fry sauce on burgers.

But the fourth surprise, and the point of this post, was/is Box Elder Bugs, Boisea rubrolineatus (pic left), which, as everyone in Utah knows, come out of the woodwork the first few warm days of Spring, as well as on scattered, warm “Indian Summer”-like days in the Fall. No really, I mean it- they actually come out of the woodwork, as in the woodwork of your house, as I’ll explain in a moment.

Box Elder Bugs occur across North America, coincident with the range of their favorite food source and home, Box Elder Trees. The Box Elder, Acer negundo, is one of Utah’s 3 native Maples, and though Box Elder Bugs favor that tree- specifically female A. negundo (Box Elder trees are dioecious, meaning trees are either male or female)- they’ll also make use of other Maples and even Ash species. There are 2 species of Box Elder Bug, which look (and behave) pretty similar: B. rubrolineatus from the Rockies West (and therefore here in Utah), and B. trivittata (pic right) East of the Rockies.

When I first encountered Box Elder Bugs I was highly disturbed. On the first (in a while) bright warm sunny day, they are everywhere, particularly on or near sunny windowsills, and when I first laid eyes on them, my first thoughts were of Cockroaches. I went to college in Philadelphia, during which time I resided in a succession of dorm rooms and apartments that were invariably roach-infested. My college years are a bit hazy now, but some of my clearest memories are of killing roaches with my bare hand and detonating chemical fog-bombs in my dorm room. So my first thoughts were, “Great. Utah Cockroaches.” But as I’ve learned about Box Elder Bugs I’ve found out that they’re far more benign than my collegiate nemeses.

The first thing worth knowing about Box Elder Bugs is that they are a True Bug. A lot of people- me most of all- throw the term “bug” around pretty loosey-goosey as sort of a catch-all phrase for all kinds of invertebrates, including insects, spiders, scorpions and woodlice. But to a real entomologist (like this guy- cool blog), the word “bug” has a very certain meaning, specifically an insect of the order Hemiptera, which includes 80,000 species of insects which all have similar characteristic mouthparts. In a True Bug, the mandibles (crush /biting /cutting mouthparts) have joined with the maxillae (steadying/ manipulating/ chewing mouthparts) to form a proboscis, which is a specialized beak-ish structure used to pierce tissues and suck out liquids.

What kinds of tissues and liquids? Usually plant tissues and sap, but not always, as we’ll see in a moment.

There are other defining features as well; Hempiterans often have partially-hardened forewings, as do Box Elder Bugs, which is different from Beetles (order = Coleoptera), which have fully-hardened forewings. But the deal with the mouthparts/proboscis is the key differentiator.

In my defense, Cockroaches look at first glance a lot like a True Bug. But to an entomologist the difference is obvious; the mouthparts are all wrong*; Cockroaches have distinct mandibles and maxillae. (diagram right)

*The wings are wrong, too.

In addition to Box Elder Bugs, you’re already familiar with lots of True Bugs. Aphids, Cicadas, Leafhoppers and Stink Bugs (Shield Bugs) are all True Bugs, as are- get ready for it- Bedbugs.

Geeky-But-Cool-Side-Note: The phylogeny, or family tree, or Hemiptera is in flux. Traditionally Hemiptera has been divided into 2 orders, Homoptera, which includes Aphids and Cicadas, and Heteroptera, which includes Box Elder and Stink Bugs. But it now appears that Cicadas are more closely-related to Box Elder and Stink Bugs than they are to Aphids, making Homoptera a paraphyletic grouping. This is exactly the same deal we saw last summer when we looked at Mules Ears and Balsamroots in the Wasatch: recent DNA evidence forcing biologists to reassess groupings of and relationships between different species, and it’s a great example of why now is such an exciting and revolutionary time in biology.

Tangent: Stink Bugs- also called Shield Bugs, for their shield-like shape- which are a worldwide group including over 5,500 species, are the second-most common insect we see inside of our house in the warmer months. I’m not sure, but I think the most common species we find indoors here in Utah is this guy, the Consperse Stink Bug, Euschistus conspersus.

Confusingly, there is another group of insects called “Stink Bugs” here in the Intermountain West, which are not actually Stink Bugs, or even True Bugs. You’ve undoubtedly seen- and probably run over- these guys if you mtn bike singletrack along the Wasatch. They’re Darkling Beetles, of the genus Eleodes, and are Beetles and therefore not True Bugs. They’re called “Stink Bugs” for their chemical defense: like true Stink Bugs, they spray foul-smelling chemicals from their rear ends when threatened, though they evolved this mechanism completely independently (yet another nice example of convergent evolution, like Vultures, as well as CAM and C4 photosynthesis.) They’re a favorite food of mice, who have figured out how to roll them over in a manner to avoid the spray.

Bedbugs (pic below, left) have put the proboscis architecture to a more dastardly (to us) purpose; they pierce animal tissues and suck blood. Bedbugs, by the way have one of the weirdest and creepiest sex lives/anatomy in the animal world. I won’t get into it here, but David Quammen’s book Flight Of The Iguana provides a riveting description. But in contrast to Bedbugs, as well as many of the other invertebrates we’ve looked at, the sex lives of Box Elder Bugs are pretty vanilla. There are no parthenogenetic females (Aphids), no deceptive, mate-stealing triploid-females (Weevils), no “throw-away” chromosomally haploid males (Bees, Ants, Wasps) and no mate-devouring females (Black Widows.) Genetically, Box Elder Bugs reproduce very much like us: gender is chromosomally determined by the male, who provides either an X or Y chromosome, while females are always XX.

Side Note: Not all Hempiterans use the XY system of sex determination. Many True Bugs, including Water Striders (pic right) and Water Bugs, use what is called the “X0” system, whereby females have 2 “X”’s, males have a single “X”, and there’s no such thing as a “Y”. An interesting corollary of an X0 system is that every male in the species is aneuploid, having an odd number of chromosomes.

Tangent: There’s actually a mammal that’s been found whose males have no “Y” chromosome, and when I learned of it I thought that it might be a mammalian example of an X0 system, but it turns out to be even weirder. The male Mole Vole, Ellobius lutescens, native to the foothills of the Caucasus Mountains has a single “X” and no “Y” chromosome. But females also have only a single “X”, and the sex determinant seems to be our old friend the SRY gene, which apparently sits on some “X”’s. So all Mole Voles- male and female- have an odd number of chromosomes. This critter is the subject of much interest to biologists because it hints at a possible evolutionary future for us mammals with our strangely shrinking (over the evolutionary time-scale) Y chromosome, but that’s something I’ll have to leave for another post…

And speaking of mating, that’ll happen soon enough. When you see Box Elder Bugs scurrying around on that first warm day, what’s going on is this: last Fall, as the weather cooled, they migrated toward any warm spot, in an attempt to conserve energy and remain alive*. They congregated on the sunny, South-facing walls of your house, and when the sun went down, they crawled inside, through cracks and windowsills, trying to stay warm. When Winter set in, they went into hibernation.

*2 quick clarifications here. First, they technically don’t “hibernate”; that’s something specific to mammals. But they go “dormant” in a very hibernation-like way. Second, I read somewhere that only females “hibernate”, but couldn’t confirm that in time for this post.

When bright sunlight again warms the South-facing walls, the bugs wake up and start scrambling. They want to get back outside, eat, mate, and lay eggs. They don’t want to stay indoors; a Box Elder Bug doesn’t lay eggs or reproduce indoors. When you see them scurrying around your windowsill, they are lost; they’re trying to get outside.

Side Note: When I learned this, a light bulb went on for me: We’ve lived in our current home for 7 years. In all that time I have never found a Box Elder Bug in a North-facing room. All the rooms we’ve ever seen/found them in- kitchen, dining room, family room, office, master bedroom- are all South-facing.

When and if they get outside they’ll start eating. Their favorite food is Box Elder seeds, which is why they’re drawn to the female trees. After a couple of weeks of eating and sunning, you’ll see them mating* everywhere, facing away from each other, joined at the rear (pic right). The female then lays her eggs (pic below, left) in crevices of the bark of female A. negundo. The nymphs (pic right, in left of photo), which look like little adults** but with bright red bodies and underdeveloped wings can be found come Summer, often congregating on their favored trees. And speaking of wings, Box Elder Bugs are lousy flyers; ~20 feet is usually the limit of a single flight segment, though a chance wind may catch one and drop it a couple of miles away.

*If, even after reading this post, you feel you simply must squash Box Elder Bugs, at least have the decency not to do so while they’re mating. That’s just wrong.

**Another distinguishing characteristic of all True Bugs is that the form of he young is the same basic structural form as the adults; they don’t undergo any kind of radical metamorphosis, as do moths or butterflies, for example.

Although many True Bugs are serious agricultural or garden pests, Box Elder Bugs really aren’t. In extreme cases they can damage or partially defoliate a female Box Elder or other Maple, but that’s really rare.

And that’s the most important thing to know about Box Elder Bugs; they’re not really pests. They don’t eat garbage, they don’t lay eggs in your cupboards, they don’t come out at night and crawl across your face. They’re just trying to get outside. They don’t bite or spread disease, so when you see one on the window sill, you might consider just picking it up and letting it go outside*.

*Or squash it if you want. They’re not endangered, and I’m not enough of bleeding heart to tell you to spare a bug or anything, but they really don’t do us any harm.

Postscript: I’ll be offline for a few. OC Rick, Clean Colin, Aurora Coryalis and I are responding to the Never-Ending Winter with pure, selfish cowardice: We’re abandoning our families and fleeing down to St. George/Hurricane for a weekend of desert mtn biking and camping.

Post-Postscript: Oh Fetch! This invertebrate-oriented post reminds me- I totally flipping forgot to do the Costa Rican Creepie-Crawlie Bonus Post! Crap. Well, I know it’s late, but I could probably squeeze it in next week sometime, if there’s interest. 3 or more “Yes, Do It” comments and I’ll do it.