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Cicadas – not just Brood X!

Chances are you’ve seen internet articles about the mass cicada emergences that’ll be happening across the eastern United States this year. Here’s a decent writeup from the National Park Service.

Periodical cicadas are named for the long stretches of time between their emergences (13 or 17 years, depending on the lineage). The thought is that this makes them an unreliable source of food for predators – it’s hard to be a specialist wasp if your food species vanishes and is unaccessible below ground for over a decade at a time.

And, when you emerge, surrounded by thousands of others like you, it’s statistically unlikely that you’ll be the one who gets eaten – be it by bird, dog, or unattended small child. Though many of your kin will be devoured, you’ll probably be safe. It’s the same tactic the now-extinct Passenger Pigeon used. Passenger Pigeons built undefended nests on the ground, and relied on numbers to make any individuals odds of survival better. A tactic that worked excellently until it didn’t.

Here we have a little member of genus Okanagana, the whip cicadas.
Fittingly for this area, they’re named after one of Canada’s First Nations which spoke a Salish tongue.

While we don’t have periodical cicadas (genus Magicicada) this far west, we do have other types of cicadas, especially genus Okanagana. I’ve been hearing their males sing in the trees on my drive back from work over the past couple of weeks. One way cicadas avoid predators is by being active in the sweltering heat when nothing wants to hunt. Cicadas cope with the heat by drinking tree sap nearly constantly, and releasing excess moisture through pores in their thoraxes, much like how we humans sweat to cool down.

Our cicadas here have life cycles maxing out in the 3-year range. As such, these species can be pretty reliable hosts for certain predators, like the cicada killer wasp… but our cicadas lead a charmed life. The Western Cicada Killer Wasp only goes as far east as Idaho, and the Eastern Cicada Killer Wasp only really goes as far west as the Dakotas.

Our local cicadas are convinced that this truly is God’s country.

An Okanagana cicada I met last fall – note that this one has brighter orange markings.
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The time to start trapping wasps is now.

While winter isn’t quite done with us yet, we’ve had a good period of warmth recently. Wasps, as well as bears, are waking from their winter hibernation. I’ve seen a few queen paper wasps scouting for new nesting sites.

With this in mind, if you want to control wasps in or around your property, the time to start is now. If you can catch and kill the wasp version of a queen, you’ll stop her whole colony from bothering you the rest of the summer.

(A wasp queen is called a “gyne”, which means “woman” in ancient Greek. Gynes are quite large – perhaps twice the size of a standard wasp. Gynes are the wasps most likely to not die in hibernation.)

While most paper wasps will try to hibernate through the winter (the reason we see them moving indoors in fall), most are unsuccessful. Most wasp queens have to start anew in spring, building their new colonies (and sometimes their nests) from scratch.

Raising kids can be hard work, as any parent can tell you. It’s no different for wasps. As gynes start building their new nest, and laying their first eggs of the season, they spend most of their time looking for food for their young.

(A gyne’s first eight or so children are called “haplogynes” meaning “half-women” – these are about half as large again as a standard wasp. These haplogynes take over caring for their little siblings, leaving the gyne free to lay more eggs and expand the nest.)

Developing wasp larvae, just like developing human children, need diets rich in protein to grow and build muscle tissue. As such, a gyne caring for her first batch of larvae will spend much of her time looking for meat to feed them with. Later in the year, wasp larvae will often be fed caterpillars. But early on, carrion forms much of the available meat.

If you want to control your wasp problem before it starts, consider setting a wasp trap and baiting it with a bit of leftover meat and letting it spoil. If you manage to catch and kill a gyne, or her crew of haplogynes, you’ll have won a war before giving it a chance to start.

(Bear in mind, we do live in an area with bears, who are also beginning to leave hibernation. Be bear aware, and cautious in your use of meat to bait wasp traps.)

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Winter Crane Flies: widespread and little-known

As I was walking over to my in-law’s place one chill and sunny afternoon, I happened to spot a fly. A gangly, long-legged fly, seeming to bounce up and down in the brisk winter air. Unlike the cluster flies lining the edges of our ceilings, this one was fairly active, despite the temperature.

Naturally, I snatched it out of the air for a better look.

It wasn’t just any fly – at first glance it appeared to be a crane fly… but parts of it weren’t quite right. It had simple eyes in the center of its forehead, something absent in true crane flies. Nor was it quite the right size – it’s perhaps 1.5 to 2 times the size of an average mosquito, whereas crane flies can be far larger, and with a broader leg-span. It was a winter crane fly.

If you look closely, you’ll find that the winter crane fly, like its true crane fly relatives,
does not have stabbing mosquito-like mouthparts.

While not true crane flies, winter crane flies are close relatives, and both develop in similar areas and eat similar foods. Wet spots on land, perhaps along a stream or seep, are perfect for a growing winter crane fly maggot. True crane fly maggots (often called “leatherjacket slugs”) prefer to swim in the stream itself, and can make excellent fishing bait. Both types of maggot like places that have plenty of moist decaying plantstuff to feed on.

Interestingly, winter crane flies have been documented gathering in large numbers underground… both here and in the Old World. I observed this in a number of western Kentucky stream caves while I was studying a group of eyeless cave beetles, but little has been written on the behavior in this organism. I wonder if it could be similar to how mosquitoes overwinter in caves…

To my surprise, Winter Crane Flies have become invasive in Antarctica in the past decade… it’s thought that they started out by colonizing the polar scientists’ sewage treatment plant, and escaped to the outside. Impressive for a wee beastie that is only active for a couple of months out of the year here. Of course, the Winter Crane Flies invading Antarctica have much less competition than those around here!

What is a pest in one place may be entirely harmless in another.

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Ask the Entomologist: Bug on my kitchen wall

“Is this a stink bug? Our house has a few of these, and they’re often walking on the walls. Why?”

Your particular leaf-footed bug is Leptoglossus occidentalis, the Western Conifer Seed Bug.
Very nice photo, by the way.

This isn’t a stink bug, but that’s a very good guess!
This is a leaf-footed bug, a close relative of the stink bugs – they’re both members of Hemiptera, what entomologists call “the true bugs”. Beyond this, leaf-footed bugs and stink bugs both belong in Infraorder Pentatomorpha. While leaf-footed bugs do emit a strong smell when stressed or handled, but it’s not nearly as strong as a stink bug’s scent, in my experience.

These bugs are similar in behavior as well – they have piercing mouthparts, and tend to be herbivorous, especially seed-feeding. Both have been crop pests – stinkbugs are detrimental to agricultural pursuits like soy farming, while leaf-footed bugs tend to be more damaging in tree plantation contexts. In some regions, both may be present as minor citrus farming pests.

Here’s a stink bug I met this fall, perched on a burdock leaf. Note the differences:
The leaf-footed bug is slender and has fins on its hind legs.
The stink bug is stout in comparison and has larger spines on its shoulders.

However, when the weather turns cold, both stink bugs and leaf-footed bugs seek shelter from the elements. In winter, both stink bugs and leaf-footed bugs build up protective alcohol-based compounds in their blood that make it much more difficult for them to freeze. However, if they do end up freezing, they die. Leaf-footed bugs are what entomologists would call “cold-tolerant, freeze-avoidant“. Their quest to find someplace warm to spend the winter sometimes leads them to bother us indoors. Without human homes to invade, leaf-footed bugs and stinkbugs both tend to overwinter inside large dead trees.

While they may be annoying for a time, rest assured that neither stink bugs nor leaf-footed bugs are harassing your houseplants this winter. During overwintering, these bugs avoid feeding – after all, the more moisture they take in, the more likely it is that ice crystals could form inside them. However, many leaf-footed bugs do release aggregation pheromones which spread the news that your home is a great warm place to wait out the winter.

As for why your new houseguests are walking on your walls, that I don’t have as good an answer for.
I imagine that your walls might be warmer than the floor, and that could make them more attractive. I’d also hazard a guess that your leaf-footed bugs prefer being on inside walls, rather than outside walls.

Thank you for the question!

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Why are there flies in my house? There’s snow outside!

If your home is anything like ours, it has had an abundance of flies lately. You may ask yourselves “why now?” – after all, it’s snowy out, and there can’t be much food for them. Shouldn’t they die with the cold like everything else?

You’d be entirely right in thinking so. Regardless of the type of fly, most of the good food sources are rather scarce this time of year, and the cold kills many. However, insects are just as uninterested in freezing to death as we are. Most of these gathered indoor flies are trying to avoid that particular fate.

My Mother-in-Law’s elegant, clear sticky traps, thoroughly filled with Cluster Flies and Fungus Gnats.

While we see many house flies, flesh flies, and blow flies in the summer, they aren’t the primary species to invade our homes in the winter (though I’ve met a few of each overwintering inside my home).

The vast majority of our new fly guests are a different group entirely – the Cluster Flies. Until quite recently, the Cluster Flies were grouped as a special sort of blowfly, but just over a year ago, they were given their own scientific family name, Polleniidae.

Cluster Flies get their name from their habit of gathering in large groups, often in windows. Some try to stay warm outdoors, nestled deep inside rotting tree trunks. More sensible ones move inside with us to stay warm and survive the winter. Cluster Flies don’t want anything to do with your food, plants, or pets – they’re just here to avoid freezing.

Eternal optimists, Cluster Flies often come out on warmer days, and try to find their way outside.
Thus the accumulation of dead ones on your windowsills when weather turns cold again.

It’s this habit of moving inside for the winter that is thought to have introduced Cluster Flies to the New World. You see, the Cluster Flies we have now aren’t North American natives. No. They’re thought to have sailed over from the Old World with some of the first European colonists.

Back when European countries were busy sending ships to build colonies in the New World, they brought many unintentional stowaways with them. Many of these scalawags are with us today, for better or worse. In this story, we care about two such emigrants. Earthworms (especially the Green Worm) and Cluster Flies.

It’s thought that earthworms were transported across the Atlantic in ships’ ballast. Meanwhile, some Cluster Flies took refuge from bad weather inside the ships themselves, just like they’re doing in our homes this winter, and so found their way to America as well.

Earthworms flourished when ships made landfall. Many of the formerly-glaciated parts of North America no longer had earthworms, and were ripe for Lumbricid conquest. The spread of earthworms, in turn, opened up North America to the spread of Cluster Flies. Both spread like wildfire, and now can be found all over our continent.

Why are earthworms important to Cluster Flies? You see, Cluster Flies are specialist parasites. Their maggots feed almost exclusively on earthworms. Mother Cluster Flies sensibly lay their little ones near earthworm burrows, and the newly-hatched maggots then see about journeying into earthworm burrows. There they lurk in ambush, waiting for a worm to pass by.

Thinking of tiny maggots catching hold of vast earthworms with their mouth-hooks as the worm passes by very much brings scenes of Frank Herbert’s “Dune” to my mind. I like to imagine the tiny Cluster Fly maggots singing this song as they hunt their earthworm prey, and carve their way inside.

Our friendly, local Cluster Fly – Pollenia pediculata.
As you can see, they’re a bit larger and hairier than our common houseflies, as well as easier to catch.

Because of their worm-based diet, Cluster Flies are actually remarkably clean compared to other flies with carrion- or dung-based diets. While you may not appreciate Cluster Flies’ presence, at least they will not spread disease.

Additionally, both my dog and I can attest to their superb flavor.

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Are there bugs in your mail?

I recently started working for the United States Postal Service, and, while I’ve been seeing quite a few bugs lately, few are the kind I like. While I’m not terribly fond of them, the sheer numbers these bugs occur in has been very impressive.

Mercifully, with elections past, there’s been a sizeable reduction in the numbers of incoming bugs in our P.O. boxes.

I’m talking about union bugs, specifically printers’ union bugs. These minuscule beasties seem to be on well more than half of our political junk mail this season! Here’s some fine examples of the species:

These strange ink-based critters colonize almost all publications that come out of unionized printing presses.

If you’ll notice, there’s a certain bias in the political affiliation of these bugs. At present, almost all Democrat-leaning political flyers are published in unionized print shops. Republican-leaning political flyers, on the other hand, are seldom published in unionized print shops, and most lack union bugs.

Republican flyer, lacking the Union Bug

This trend doesn’t necessarily hold constant across the country, though. Nor has it held constant over time – unions used to be strongly supported by the right, as a way that capitalism led to better worker conditions. And, alas, the presence of the union bug is no longer as indicative of an entirely union-made product as it once was…

Due to prevalent local political sentiments, certain political flyers have been disguising themselves to sneak their messages into new homes. Take a look at this piece of political mail – at first glance, you’d assume that LR-130 is opposed to the Second Amendment.

But look closer!
A union bug. This indicates a union press was used, and the flyer in question was most likely published by a left-leaning group. When we examine the bones of this legislation, LR-130 is actually in favor of the Second Amendment.

Cleverly camouflaged flyers and a fair bit of funding led to a surprisingly close vote on LR-130. It’s important to be well-informed on what the issues we’re voting on actually are – legislation and flyers rarely aim to be straightforward.

Mercifully, while pests of a sort, political flyers do not reproduce, unlike invasive insects. Personally, I’m rather grateful that we only have to deal with this volume of political propaganda once every four years.

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Ask the Entomologist: Massive spider

This past week I had an identification request from a bit closer to home. This giant spider was perched right below one of our windows and my wife wanted to know what it was.

Araneus gemma, the Gem-Shaped or Cat-Faced Spider.

While I’d seen and admired her webs before, this was the first time I met the web’s weaver. She must have spent most days hidden behind the window AC unit. Revealed now that we’d removed it, now that fire season and the heat of summer seem to be past.

As an entomologist, I have to say that I’ve met larger spiders, but this is the largest one I’ve seen up here in Trego. She’s an Orb-Weaver, a spider in family Araneidae. These are classic storybook spiders, straight out of Charlotte’s Web. When you see those beautiful wheel-shaped webs, big and round, full of droplets from the morning’s dew, these are the spiders responsible.

I rather like Orb-Weavers – these spiders have pronounced sexual dimorphism. Females are often far larger than males – routinely twice the size, sometimes up to four times as large. Our A. gemma was quite large for her species, a 2/3 inches across the abdomen, and over an inch in length if we measure from the tip of her abdomen to her outstretched legs.

At over an inch in length, she’s one of the largest spiders I’ve met here.

As far as medical importance is concerned, the Gem-Shaped Spider’s bite is harmless to healthy humans. Additionally, I’ve handled many related Argiope orb weavers, and have never been bitten by them, so I don’t think receiving a bite from one of these is likely. However, if you or your loved ones are immunocompromised, elderly, or very young, more caution may be merited.

Which common name do you prefer – the Gem-Shaped Spider or the Cat-Faced Spider?

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Shiny flies

Earlier this week we visited Trego School, to see the results of the salmon snagging fieldtrip. After the fish were had been cleaned and packed away for children to take home, I saw many bluebottle and greenbottle flies, as well as a few paper wasps, flying about outside of the school, sucking up fish juices.

Bluebottle and greenbottle flies are blowflies, members of family Calliphoridae, a name which translates to “carriers of beauty”. Rather fitting, given their bright metallic hues. Additionally, adult blowflies are excellent pollinators, and a very good thing to have in your garden.

Two greenbottle flies, genus Lucilia, contemplating romance over a salmon dinner.

Blowflies have an incredible sense of smell. In most parts of the world, blowflies find bodies within minutes of death, detecting the first smells of decay long before humans are able to. When they find the right sort of decay (some blowflies prefer dung to death), blowflies quickly mate and lay eggs before flying off.

People throughout ancient Greece and Egypt believed that these shiny flies were the souls of the dead. Even today, some people in those countries consider it bad luck to swat at them, for fear that you might kill someone’s ancestor. I think this is a particularly beautiful story.

Imagine, sitting gathered with family and friends as a loved one passes on, breathes their last breath. Within minutes, you can see their soul, in the form of a beautiful fly, flying about their mouth, nose, and eyes. Almost as if the soul is sorry to leave the body, as if the person wants to stay with their family. Perhaps they say “goodbye” before flying off to the afterlife.

Today blowflies are appreciated for more than their attractive colors and spiritual significance. They are the most useful insects in forensic investigations – their young are very useful for figuring out time (and sometimes place) of death. While other insects can be used, blowflies are a forensic detective’s best friend.

Blowfly maggots have even been used in medicine, as a way to clean dead flesh out of wounds, preventing sepsis and gangrene. Medical maggot use predates antibiotics! Napoleon’s surgeons noticed that fly maggots increased soldier survival! In the American Civil War, both sides used blowfly maggots to clean deep wounds. Maggots continued to serve and save lives in World Wars I & II, and are used for some conditions even today.

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Ask The Entomologist: Fluffy caterpillars

Last week I received an “Ask The Entomologist” identification request.
What is this fluffy caterpillar? It was found feeding on blackberry bush leaves.

First off, adorable. This is a Tussock Moth caterpillar, so called after the little clumps of hair on their backs. Many fluffy caterpillars are in this group, family Lymantriidae. This particular species is called the Spotted Tussock Moth, and is native to our region. It’s not a picky eater, and will gladly eat willow, birch, and a range of other deciduous trees. We have another related species in the area, the Douglas Fir Tussock Moth, which can become an awful lumber pest, and has been linked with some health conditions in forestry workers.

Beware! While Tussock Moths’ long hairs can feel soft if you stroke them gently, they often conceal shorter special defensive hairs! These “urticating” (itchy) hairs are like tiny spears and can be quite painful – some even come with venom. Many types of Tussock Moth urticating hairs can cause allergic reactions, the Spotted Tussock Moth (the one above) has even caused one case of anaphylactic shock. Even if you’re not allergic to the caterpillars, there’s the possibility of bacterial infection if the hairs break off beneath your skin.

Tussock moth caterpillars can prove even more dangerous if eaten! Whether by livestock (abortions in mares, presumably others as well), pets (tongue rot documented in dogs), or unattended toddlers (often surgery, no deaths reported yet…) . The most serious condition resulting is that the eaten caterpillars’ hairs can puncture the digestive tract. This may cause bacteria to seep from the intestines into the body cavity, and can cause serious illness. While a healthy organism may be able to survive this, it often proves fatal to unborn young, which don’t have sufficiently developed immune systems.

These caterpillars can be perfectly safe, and kids can have a great time watching them grow up into pretty little moths, but do be careful! If you think you, your kids, or your pets have been injured by contact with a caterpillar, Mayo Clinic has some medical advice. If you want to kill your Tussock Moth caterpillars, I suggest rubber gloves and a jar of soapy water.

Looking forward to more bug questions,

EntomologistJed

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Wasp control

I’d wanted to talk about how to read wasp body language this week, but that’ll be postponed. I couldn’t persuade any individuals to do threat displays this week – all live wasps were well-mannered, despite extreme invasion of their personal space.

Most of the wasps I’ve seen around Trego are Polistes paper wasps. We have two main species here – the invasive European Paper Wasp (Polistes dominula) and the native Golden Paper Wasp (Polistes aurifer). In our area, Golden Paper Wasps peak in July, while the European Paper Wasps peak in August. While both are still around, I’ve been seeing far more European Paper Wasps lately.

The European Paper Wasp is rather special, in that it doesn’t mind reusing old nests from last year and making them bigger. Because of this, they often reach a larger colony size faster than their native wasp competitors can. As such, these are likely to be most of the problem paper wasp nests you come across.

The best bait for trapping wasps will vary by season. My neighbors have been having great success baiting their wasp traps with scallop and chicken… this means that the wasps that they are catching are from nests with many developing wasps!

A meat-baited trap full of European Paper Wasps – this indicates that there are nearby nests full of wasp larvae.

At this, another friend present asked me why folks these days trapped wasps with meat – he remembered his grandmother having lots of success baiting wasps with beer. The answer is that it depends on the season, and what part of their life cycle the wasps are in…

Early on, a wasp nest is focused on growing: laying eggs and raising larvae to adulthood. Little humans need healthy food, protein to turn into muscle tissue. The same is true of young insects: adult wasps prefer to feed their larvae with protein-rich foods (any meat – caterpillars or dead deer, it makes no difference). If you’re seeing wasp nests with lots of brood cells by your home, consider putting a bit of meat, especially spoiling meat, in your wasp trap!

A nest of the invasive European Paper Wasp – note the cells capped with silk, these contain developing wasps.

Adult insects, however, aren’t going to build any more muscle than they already have. We mammals can continue to develop our musculature throughout adulthood. Insects only get bigger by molting, and almost all adult insects do not molt.

Though they don’t grow, most adult insects do spend a lot of time flying. Flying is very energetically expensive (it’s why hummingbirds are such sugar junkies). Likewise, adult wasps prefer to eat high energy, sugary foods. If you’re trying to trap wasps later in the season, when they’re reproducing less, you’ll have better success baiting them in with sugar solutions, juice, or alcohol.

Here’s good instructions for making a wasp trap – bait it however you’d like.
As always, be aware of your local wildlife when setting up insect traps! If you’ve got a bear in the vicinity, it’s probably best to hold off on trapping for a while. They’re at least as fond of meat and booze as the wasps are…

Next week: Wasp body language: how to tell if they’re aggressive.
(for real this time – none were aggressive towards me this week, so no useful photos).