University Place

Outdoor Insect Hazards: Biting and Stinging Pests

– My name is PJ Liesch. I’m an entomologist at the University of Wisconsin-Madison. I’m director of the UW Insect Diagnostic Lab. In a nutshell, it means I get paid to identify bugs for people, which is a very, very fun job. I get to see all kind of cool stuff. There’s a lot more to it than that. I have a big outreach component as part of my job, giving talks and seminars throughout the state. This is actually my seventh seminar this week, so if my voice is a little hoarse, I do apologize.

I’ve been on the road quite a bit. But what we’re talking about today needs very little introduction to us. You go outside in Wisconsin during the summer months, it seems like you don’t have to wait very long, and there’s something trying to bite you, or sting you out there, it can ruin camping trips if the black flies are out in force, so we’re going to talk about all that good stuff today, things that bite, things that sting, and what you can do about them.

So to give you an idea of what we’re talkin’ about, I’ll give you kind of a roadmap on the next slide. The first thing I want to mention, though, is a publication, Outdoor Hazards in Wisconsin. It’s a UW-Extension publication. If you’d like to find it, you can find it on the UW-Extension Learning Store website, which I have posted up on the screen, and its Publication number G3564.

And by the way, I forgot to mention, I have the notes, handouts, for today’s lecture, so if you want this information, on my very last slide I’ll have a link to my webpage. You can go there, they’re posted online, download ’em and print ’em off or view them at home on your laptop or tablet or phone. But this is a great resource, it talks not only about insects and ticks and things like that, that can bite or sting, it also talks about dangerous plants like poison ivy and wildlife in general.

So, you can see it’s a slim booklet, maybe about 25 or so pages long, but a lot of good information about things outside that might cause irritation to us or could pose some other hazards, so I always like to mention some publications and additional resources.

All right, so to that roadmap, what are we talking about today? We know that there’s quite a few different things that can bite or sting, and I’ve arranged them in terms of kind of a ranking of risk to us, so we’ve got some at the top, the ticks and mosquitoes.

We’re going to spend an awful lot of time talking about that, because in the grand scheme of things, those can pose some very significant health risks to us, spreading diseases like Lyme disease, so we’ll talk a lot about what are ticks, what we can do about them, and dealing with them in our yard, same kind of thing with mosquitoes. We’re going to spend a lot of time talking about mosquitoes. We’ll wrap up today talking about wasps and bees. We know that those can sting.

With most individuals, you may get a localized reaction, redness, it burns for a little bit, and that’s about it. Some folks do have sting reactions, so I don’t want to belittle the fact that wasps and bees can pose very significant risk to sensitive individuals, and then towards the bottom here we have some insects that I consider more of a nuisance issue for us.

They’re not really spreading disease, but gosh, if you bump into these and they’re out in force, they can bite and really ruin your weekend camping trip if they are there in high numbers. So we’re talking about horse and deerflies. We’ve probably all bumped into up in the Northwoods or swimming at a lake or a pond, things like stable flies, which you have probably bumped into, you might not have recognized what they were.

It’s kind of a relative of house flies, that happens to bite, we’ll talk about black flies and biting midges, or those are also known as No-See-Ums or punkies as well, so we’ll talk about all these creatures and what you can do about ’em. But first and foremost, let’s talk about ticks, and actually, the talk title was Outdoor Insect Hazards. Remember, ticks technically aren’t insects.

They are arthropods though, so they’re related, although they’re from a group we call the arachnid, so they’re technically more closely related to things like spiders, but we know that ticks can bite us. How do we know that they’re not an insect? Too many legs on the body. If we look at this diagram here, or this picture, we can see that that adult tick has eight legs on the body, so that cues us in it’s an arachnid.

I will point out though, at a certain point in their lifecycle, the smallest juvenile stage, the larval ticks, when they hatch out of the egg, they only have six legs on their body, so if you ever encountered a very, very tiny tick, or something that looks like a tick, the youngest juvenile stage only has six legs on the body. Once they molt and go to their intermediate nymphal stage, they’ll have eight legs, and the adults have eight legs as well.

So that again cues us in that they are arachnids. And ticks in general are typically flat, kind of hard to squish, and they have small size. Ticks don’t get to be particularly large creatures. And the size of a tick is going to depend on the growth stage, is it the youngest larval stage, the intermediate nymphal stage, or is it an adult tick. It’s also going to depend on the tick’s species. Some tick species are simply larger than other ones.

All right, so before we talk about ticks, I want to bring up a few of the misconceptions that are out there about ticks. There’s a lot of urban myths about ticks, them jumping out of trees, falling out of trees, being able to fly and things like that. Well, ticks don’t have wings, so they can’t simply fly, so that’s an easy one. When it comes to climbing up, many ticks have a behavior we refer to as questing behavior. What that is it’s a behavior pattern where ticks are looking for a host.

They typically climb up onto low vegetation, maybe a foot or two, maybe three feet off the ground, so tall, weedy grass, materials like that. One significant challenge that ticks face is this constant battle to maintain enough moisture in their body.

They may climb up to the top of this weedy grass, and if they’re gettin’ baked in the sun, they start losing moisture from their body, so they have to climb back down to ground level and rehydrate, and they may be doing this process again and again throughout the day. So for a tick to climb 30, 50 feet up in a tree, that’s like wandering through a desert without water, so just biologically speaking, it wouldn’t make sense for them to do that.

Many ticks don’t have eyes, so the thought that they would jump down from trees to try and land on a host doesn’t make a whole lot of sense either. We’ll also talk about some of the tick removal methods. I remember as a kid hearing methods ranging from smothering them with Vaseline, to burning them, and some of those tactics probably aren’t the best, so we’ll talk about how to remove ticks as well.

So a little bit of an intro myth-buster session, but let’s talk about our three main tick species that we have in the state, and there’s really more than this. Some ticks are very particular in the animals they go to. And if you’re not looking for those particular animals, you’re just not going to bump into them. We’ve got three tick species that we can bump into with some regularity. The wood tick or American Dog Tick, this would be perhaps our commonest tick in Wisconsin.

And if I had to pick one of the ticks out of the three I’m going to talk about to be bitten by, it’d probably be this one, because we have the fewest problems with it. Wood ticks can have certain diseases associated with them like Rocky Mountain spotted fever and tularemia, but in terms of the cases we see in the state, in the Midwest, we see very very few cases overall. So I don’t want to belittle the fact that these ticks do carry disease, but typically we don’t see many issues with these.

And we can bump into wood or American dog ticks pretty much any time during the warm season, spring through the summer months, into late summer. So that one was our commonest tick. Then we have one that we’re starting to bump into, but it’s really not very common at this point. This is a species called the lone star tick, and if you really wanted to find lone star ticks, you should head farther to the south, places like Missouri, Tennessee, Kentucky, Virginia.

I’ll show some maps that’ll illustrate that point, again, with some of the diseases that these carry. So the main point I want to make about lone star ticks, they’re more of a Southern species. They have started showing up in Wisconsin in the last decade or more, but we don’t see many of them. And there’s no real pattern we’ve been able to find at this point. We, in a given year, might find one here, one there, one there, so kind of scattered introductions.

They probably don’t fare particularly well in a cold hard winter, and we just came out of an arctic blast, so for ones that are here, hopefully that will knock them back a bit, but this is a species that has some very significant health concerns with it, diseases like ehrlichiosis, which you might have heard about.

One other weird thing associated with this tick, they have a component of their saliva called alpha-gal, with some individuals, you are bitten by these lone star ticks, and your body reacts to this compound. That same compound is found in red meats, so sometime later, you’re at a ballgame or havin’ a cookout, and you have a burger or a hot dog or a steak, several hours after that, you start feeling really crummy. In some individuals, this allergy to red meats is going to fade away over time.

In other folks it might be somethin’ that hangs along a lot longer amount of time, but it can cause in some individuals very severe reactions, anaphylactic type reactions. In other folks it might not be as severe, but if you have heard about this in the news, that’s what’s going on, some individuals are bitten by this lone star tick and develop that allergic reaction to red meats.

And if you’re like me and you love a good burger or a steak, that’s not somethin’ you’d necessarily want to have happen to you. And then our third species I want to mention, deer ticks. And this is really perhaps the biggest tick concern that we have in Wisconsin, and when you want to talk about overall emerging health threats. We hear on the news about things like Ebola in certain parts of the planet. We hear about Zika virus in the news.

We’ll talk about Zika virus briefly when we discuss mosquitoes, but if you want to talk about an emerging health threat really relevant to Wisconsin, it would be deer ticks and Lyme disease. The reason for that is, we didn’t find our first deer ticks in Wisconsin until the late 1960s. So that’s only 50 years ago, so this is something that has popped up in the last couple of decades that we’re dealing with, that’s an emerging health threat to Wisconsin and surrounding areas.

In terms of the species, we see kind of two main peaks of activity, see a lot of activity and reports in the spring, so April and May, by early to mid-June. These ones are kind of quieting down. We do also see some activity in the fall. That’s often when the new adults emerge.

In terms of the diseases associated with this one, Lyme is the one we’ve heard the most about, but there are some other diseases as well, such as anaplasmosis, babesiosis, which is a malaria-like disease, and then there are some other diseases that can pose some very significant concerns, certain viruses like Powassan virus, which can be lethal in some cases, so this tick can carry a lot of different diseases in our area.

And just to illustrate on that last point, this is the original publication, came out in January of 1970, and this is really the first reports of deer ticks in Wisconsin, so this hits home that notion that deer ticks to us are relatively new. This is something that has emerged in the last 40 or 50 years here in Wisconsin, but it’s become a very, very big deal. Now in terms of tick biology, and this is going to be true of the ticks I just mentioned, we have what we call three host ticks.

And what that means is, the juvenile ticks hatch out of eggs, we can see that over here, number one on the diagram there. So the eggs hatch out of the tick, the youngest larval stage then has to find a host, typically a small mammal, it’s going to take a blood meal, and after it has that blood meal, it can molt and develop into the intermediate or nymphal stage. It then has to find another host, maybe a little bit larger creature.

It’s going to take another blood meal, and then it can finally molt into the adult stage. So when you think about it, ticks aren’t feeding all that often, they feed once, then they turn to the next stage, they feed again, they turn to the adult stage. This entire process for our ticks takes two years, so that means if there is some type of weather event or something that might influence ticks, we might not necessarily see it right away. There may be a lag with this two-year life cycle pattern.

So sometimes it’s hard to pick out trends of what is going to happen with ticks in our area. To get back to the diseases, and this will kind of reiterate some of the things I mentioned with the ticks, and the common ones we have in our area. So I mentioned some of these diseases like Lyme, we see there in the bottom right, with the purple dots on the map. And there’s two things to point out on the map.

We have an awful lot of cases of Lyme disease in Wisconsin, is really shaded in, another thing is we see lots of cases in New England area, they’ve got a lot of deer ticks and Lyme out there as well. The other diseases that are spread by deer ticks, babesiosis, with the orange dots in the upper right, we again see the same kind of pattern. Some spots in Wisconsin, some spots over in New England, same pattern with anaplasmosis, with the green dots in the upper left.

Bunch of cases in Wisconsin, bunch of cases out in New England. It makes sense, that’s the area where we’re finding deer ticks and those are the diseases carried by deer ticks. The chart in the bottom left, with the blue dots, that’s ehrlichiosis, that is a disease transmitted primarily by the lone star tick, which I mentioned is more of a Southern species.

So, we don’t have many of them up here, but if you go south a ways, Missouri, Tennessee, Kentucky, places like that, that’s where you can bump into those ticks with much more regularity, and so it makes sense, that’s where on the map we’re getting reports of those. Although if you can look in closely, there’s a few dots here and there in Wisconsin, so we do have these diseases that can be a very significant concern for us.

Of the diseases that I’ve mentioned, Lyme is perhaps our biggest concern in Wisconsin. That’s the one we hear the most about, so what is Lyme disease? Well, it’s caused by a bacteria called a spirochete, and they get that name because you can see in the lower left-hand corner, they have this spiral or corkscrew shape to that microorganism, so that’s the actual organism. It can be carried by deer ticks.

If you are bitten by a tick that is carrying it, in a lot of the cases you’re going to get a bull’s-eye-like rash, perhaps even up to about 75 or so percent of their cases, but it’s not a guaranteed sign or symptom. There’s still about a quarter of folks that won’t get that bullseye rash, but that rash is a pretty diagnostic feature for them. Other symptoms you might have, you’re just going to feel crummy, achy, joint pain, and things like that.

One piece of good news about deer ticks and Lyme disease, they’re not born with it. So when that larval tick comes out of the egg, it does not have Lyme disease yet. It has to take a blood meal from a small rodent, and that’s kind of a roll of the dice, are they going to pick it up at that point? And at the moment, that next nymphal stage, about 20% of the ticks in Wisconsin are carrying it. Then they have to take another blood meal to turn to the adult stage, so it’s another roll of the dice.

And at the moment about 40% of the adult deer ticks in Wisconsin are carrying Lyme disease, so that’s almost half, that’s almost a coin flip in terms of deer ticks carrying Lyme disease. Some studies have found certain spots in the state, it might even be closer to 60%, so there is some variability within Wisconsin.

Now, what can we actually do about ticks? ‘Cause I just said ticks can be scary, they can carry these diseases, luckily there’s a lot of different things that we can do, ranging from things we can do in our yard, to things we can do to protect ourselves and our pets and kids. So, let’s talk about all of these individually. First and foremost, landscape management. So I’m talking about things we can do to alter our yard or the landscape around us.

In general, ticks don’t do very well in open, sunny, dry areas. I mentioned earlier, ticks have this ongoing battle, they need to maintain enough moisture in their body. So if your yard is nothing but a sandbox, that’s a very, very poor tick habitat. Same kind of thing with home lawns. If you’ve got lawns that are mowed regularly, and it’s relatively low turf height, open, sunny, especially if you get some breeze through there, that’s not great tick habitat.

It’s just too open and too dry for them. Same kind of things with mulched areas and pavement. Not good tick habitat, they need moisture. They need vegetation, vegetation is habitat for small mammals, that may be serving as a blood meal for some of the life stages of the tick.

What is good tick habitat? Well, if you have situations like these pictures I have on the slides, maybe we have a grassy path, or you could even have a hiking path, where it’s mulch, but you have a lot of vegetation along the edges of it, that can be prime tick habitat.

I’ve gone on lots of walks with my wife and our two dogs, and you take a look at the tall brome grass, weedy grass, the edge of the path, and if you got good eyes, sometimes you’ll actually just see the ticks sitting on the edge of the blades of grass, waving their legs, they’re hoping for a hiker or a dog or deer to wander by. So that can be good tick habitat.

Another thing, there have been several studies that have looked at certain types of plants out in the woods, and there have been studies that looked at some of the invasive shrubs in North America. It turns out some of these invasive shrubs can make dense thickets, which can be good habitat for some of the small mammals, like some of the rodents that can serve as a blood meal for some of these ticks.

And so we know in some of these papers, they’ve looked at things like honeysuckle, or Japanese barberry, that make these very, very dense thickets, and if you go in and you thin those plants out, that may be a way to manage the landscape to help with some of these issues, so there are some things we can do in our yard.

One other consideration, if you live in an area that perhaps butts up to a woodlot, or you’re just in a wooded yard to begin with, but maybe you have some turf closer to the house, maybe that’s a better place to put your kids’ playset or your garden, rather than back near the edge of the woods, put it in the sunnier location, where it’s going to be warmer, drier, because we know that ticks don’t like that area as much.

In terms of personal protection, what can we do to directly protect ourselves? Well, long sleeves, that way we have a physical barrier. We’re talking about especially long pants, ’cause remember, ticks aren’t climbing up in trees. They’re more of about waist level on down, so that’s where they’re getting on to us. They may climb up higher on our body, but typically, they’re gettin’ onto our lower extremities.

So if we have on long pants, boots, socks, maybe even taking an additional step and tucking our pants into our socks, that can be another good precaution, so you have a physical barrier and the ticks can’t get to skin. So that’s one thing we can do. We’ll talk about repellents in just a moment. There’s a number of different repellents out there, and one really important thing, doing tick checks for yourself, for kids or grandkids, and also for pets if you have pets in the home.

One of the reasons I say that is that, with deer ticks and Lyme disease, for a deer tick to the effectively transmit Lyme disease, they typically have to be attached and feeding for about 24 hours or longer. And the longer they’re attached, the greater the chance, if they’re carrying it, that you’re going to have transmission.

So if you have a tick that’s attached 36, 48 hours, that risk really goes up, so with that said, if you do regular tick checks, and you go out on a hike, and an hour later you take a tick off you, it hasn’t been attached very long, and so that can greatly minimize the risk of it having transmitted Lyme disease.

If you do find it tick on you, what should you do? And I mentioned before, there’s all kind of techniques wandering around the Internet and by word of mouth, smothering it with Vaseline, and burning it, and things like that, and really, we don’t want to do that. One of the best things you can do is use tweezers or forceps, grab it at the base of the head where it’s attached to yourself or a kid or an animal, and a slow steady pull is probably the best thing you can do.

That is going to help minimize the chances that we’re going to break off some of the mouth parts and leave those embedded in the skin. I just discussed the tick checks, can be important with things like Lyme disease, because those ticks have to be attached really a fairly significant amount of time to effectively transmit Lyme, so if we’re takin’ ’em off relatively quickly, that is an additional precaution.

Couple other notes, it can be helpful to simply save the tick, and try and get it identified. If it’s a wood tick, and it’s not a deer tick, then we don’t have the concern about Lyme, so knowing what tick it is can be very helpful. I have some resources on my diagnostic lab website. One other website I’m very, very fond of, it’s from the University of Rhode Island, it’s called Tick Encounter. If you simply do a Google search for Tick Encounter, you’ll be able to find it.

I think the web URL is actually tickencounter.org. They’ve got some really great pictures on there of how to identify the various tick species found around the US, and the various life stages as well, so that can be very helpful.

One other thing, if you are interested in testing, some folks just want to know, I found this deer tick, I know it’s a deer tick, does it actually have Lyme or anaplasmosis or one of these other diseases? I unfortunately don’t have the capabilities to test ticks at my lab. There are some labs around the country that offer testing services, and this is actually on that tickencounter.org website I just mentioned.

so if you have a tick, you want to know, is it actually carrying a disease, you can go to that tickencounter.org website. They have a link on their menu bar. It says, “tick testing,” question mark. You click on that, it’ll take you to a web page with a list of labs around the nation that offer testing services. Now these are commercial services, so it does cost money.

It’s typically $50 or $75 on up, but if you simply want to know, did the tick that bit my grandchild have Lyme, this would be the way to go about doing that, so I want to mention that as resource. One other thing, as I said, if we remove ticks quickly, that’s the best-case scenario, I mean, I suppose even better case scenario is not to have ticks bite us in the first place. But remove them quickly, if you do have any concerns, kind of keep an eye on things over the next couple days or weeks.

If you start feeling crummy for any reason, get in touch with a physician and mention to them, you were bitten by a tick, because in terms of treatments from the physician side of view, the earlier treatments are started, the better the outcome for these types of tick-borne diseases.

Some other ways we can protect ourselves, repellents. And there are some really good repellents out there. I will point out though, you have to make sure to follow the directions on the container. Some of these repellents say you can apply them directly to skin, some of them might be, say, higher concentration, and will say you should only be applying them to clothing, so make sure to read and follow those directions.

There are a number of EPA-approved repellents that have been tested for tick repellency. Things like DEET is one of the gold standards, and Picaridin, and there are some other ones. Typically on the container they may have a logo similar to this, that we can see on the bottom right. And it’s going to tell you how long it’s going to be effective, and how often you need to be reapplying it.

So if it only works for four hours, and you’re on a weekend camping trip, you may be having to reapply it fairly frequently, whereas other formulations and products might last for 10 or 12 hours, so keep that in mind and really be familiar with what you’re using, but there’s a lot of options out there.

One other type of repellent product I want to mention is called permethrin, and you can buy permethrin products at outdoor clothing stores like REI and Bass Pro Shop and Gander Mountain, and all those types of places. It’s a repellent that has insecticidal properties, and we don’t use this on ourselves, we can treat clothing with it though, and you can actually buy outdoor clothing that’s impregnated with permethrin and it does two things, the first is that it irritates ticks.

So if you have clothing that has been treated with permethrin, they contact it, they don’t like it, and they basically detach from you and leave. Well, if that’s good enough, prevents tick bites, that can work. If they contact it long enough, it can actually kill them, though, so it offers some additional protection. So where would something like that be helpful? Well, maybe you have one particular favorite pair of hiking pants or hiking boots, you could treat those.

Usually the little container you can buy is enough to treat a couple items of clothing, so maybe a pair of pants, pair of boots, pair of socks, that sort of thing. So that is an option that is out there. So if you’re doing a lot of outdoorsy stuff, or if you’re just in a wooded area, and you know there’s a lot of ticks in your neighborhood or in your yard, that might be a helpful approach. If you know you’ve got ticks every time you go out gardening and so this would be an extra precaution.

In terms of pets, if you have dogs or outdoor cats, we want to make sure that they are protected as well, because they can also be bitten by ticks, and can pick up things like Lyme disease. I will mention, there’s a lot of different veterinary products out there, so always chat with your veterinarian to figure out which product is best and what dosages to use. And I do want to point out that there are some differences.

There are some products that are only registered for dogs, and you wouldn’t want to use those on cats. So make sure you’re choosing the right product. Also, for things like dogs, there is a Lyme vaccine available. So I want to mention that as well, and just the same way that we have to do tick checks to humans, we should also do tick checks to our pets. So that can be a helpful approach, if you have any four-legged friends you take hiking with you.

All right, so imagine a scenario where you live in a wooded area, and you know you have ticks in your yard. You encounter ’em when your kids go out to play on the swing set and things like that. In a case like that where we know there’s lots of ticks around, are there some additional things that we can do? Yes, there are, one of the things we can do is use a broad-spectrum landscape insecticide.

So these would be things you could find at the hardware store for treating insect pests in your lawn, things like Sevin or carbaryl, is the ingredient now, and things like permethrin, that same repellent product we can use on clothing. They have different products you can get at the hardware store that you can apply to the landscape. And we don’t need to necessarily treat our entire lawn.

The reason for that, and I talked about this earlier, ticks don’t like to be out in the open, where it’s warmer, sunnier, and drier. So we know from some research that’s been done out in New England, if you have a wooded yard like this, and we can see in that picture, we’ve got trees there, and that meets the lawn.

From some of the research, we know that the majority of the ticks found in a yard are going to be within about eight to 10 feet of that edge, and they’re not necessarily going to wander all the way up to the house. So with that said, if we know the ticks are coming from the woods, and maybe wandering into the yard, we don’t have to treat the entire lawn, we can treat just a band, use like a liquid product, and give it a good soaking, where the woods meets the lawn.

And so that can be a way to stop them from wandering into their yard. One other thing we can do, if you have a wooded yard, and there’s just ticks everywhere, and you’ve got good rodent habitat, there are some products out there called tick tubes that you can purchase off the Internet, or from various vendors at stores.

All it is, it’s essentially a cardstock tube, and inside are some cotton balls that are impregnated with permethrin, and small rodents will crawl in there, so mice and things like that, they grab it, they like to use that treated cotton, as nesting material. So they take that back to their nest. And we’re kind of getting at the source, ’cause remember, the juvenile ticks have to bite mice and things like that to pick up Lyme to begin with.

Well, if the permethrin is in their nest and the ticks are being killed then, that can be an additional precaution. So again, if you are in a situation where you have very heavy tick pressure in your yard, that can be an additional step that you can take. And then the last thing I want to mention for ticks. I have some colleagues on campus in the Midwest Center of Excellence from the CDC of Vector-Borne Disease.

They have come up with a tick app, which they’re using to help do some research here across the state, and also across the country. If you are interested, it’s available both for Apple and Google Android devices. I’ve got it on my phone, and basically, during the tick season, every once in a while, it’ll send you a brief survey, asking you a couple of quick questions, it takes a few minutes each time.

Did you encounter ticks today, what type of outdoor activities did you do? That sort of thing; it’s helping researchers get a better idea of what are the landscape factors that affect ticks, so if you’re interested in that, it’s freely available online.

Otherwise, moving on to mosquitoes, and who bumped into some mosquitoes last year in here?

(people laughing)

Pretty much everyone, okay. Last year was an extremely wet year. Rainy year means we’re going to have a lot of mosquitoes. Well, what’s a mosquito to begin with? It’s a type of true fly. True flies come from a group we call the order Diptera, di meaning two, tera meaning wings, so if you look at a mosquito up close, they only have two wings on their body. They’re from a specific family Culicidae, and the thing about them is they have sucking mouthparts.

And we all know this, we’ve all been bitten by mosquitoes. And it’s really the female mosquitoes that take a blood meal. And I will point out, not all mosquitoes like to bite us, believe it or not, there are plenty of species that may have a strong preference for taking blood from amphibians or birds. But we still have plenty that will bite us and take blood, and we know that there are plenty of mosquitoes that can be associated with diseases. The things about mosquitoes is, you need water.

At a certain point in their lifecycle, for the juvenile or larval stage, you need water. If you have no water, you’re really not going to have mosquitoes around, but we’ll talk about that in a bigger context in just a moment. When it comes to the water that they like, each mosquito species differs in terms of the type of water. Some mosquitoes like very stagnant, marshy water, where you got cattails and things like that.

Some prefer very ephemeral water, that might only be present for two weeks or so after a heavy rainfall event. So, in Wisconsin alone, we have about 60 different species of mosquito. Each mosquito has a distinct preference in terms of the type of water they like.

Is it moving or slowly moving or completely still? Is it stagnant, is it clean? And how long is that water going to sit there for? Is it a permanent body of water, versus is it something very temporary and ephemeral? So there’s a lot of different preferences there between the different species. In terms of the mosquito larvae, what do they actually do? Well, they’re feeding on debris in the water, typically organic debris like fallen leaves.

There are some species that like sewage and things like that and can live in some really mucky environments. There are a few predatory species of mosquito larvae that actually feed on other mosquito larvae. So there’s a few good ones in there, but most of them are just scavenging on plant debris.

One other thing to talk about, for last year, we said we had a lot of mosquitoes, well this is why. This chart shows the cumulative precipitation for Madison, Wisconsin, I picked on Madison ’cause this is where we are at the moment. That blue line on there, that’s the 30-year precipitation average curve, so we can see throughout the summer, that steadily goes up, the green line on that chart is the actual rainfall we saw last year in Madison.

So you can see essentially all through spring, summer, and especially when we got to late summer, we had those major flooding events, it really jumped up, so by the end of the year, we were about a foot ahead in terms of precipitation, so it makes sense, you had a lot of rainfall, we had a lot of mosquitoes. Interesting thing though, having lots of rainfall doesn’t necessarily mean more mosquito-borne disease. And we’ll go into the details of that momentarily.

Just to reiterate though, mosquitoes need water at a certain point in their life cycle, that would be the juvenile stage, so we see it at the three o’clock position on that graph. Start out with eggs, all mosquitoes start as eggs. They hatch, and on the five, six, through about eight o’clock position.

Those are the mosquito larvae on that graph, so they’re feeding typically on fallen leaves, they eventually turn to that pupal stage, which will also be present in the water, and eventually they emerge as the imago, or the adult mosquitoes. The males are mating with females, going off to sip nectar, and then the females are looking for blood meals so that they can produce their batch of eggs.

Now, for the mosquitoes in Wisconsin, we actually have about 60 different species, not all of these like to bite humans, again. When you look at these 60 different species, there’s a lot of differences in biology and habits and where we find them. We can lump them into about four main groups though, and I’m not going to talk about all of these. That first one, snowmelt mosquitoes. They basically use the meltwater from snow in spring, and then they’re done for the year.

So, there’s a batch of mosquitoes with that behavior. We’ve got some container breeders that breed in tires and hollow rotten parts of trees and things like that. Two groups I’m going to go into a little bit more detail about though are the permanent pool mosquitoes and the floodwater mosquitoes. So, we essentially are categorizing mosquitoes by the type of water they like to use, snowmelt versus flooded rainwater, and so on. So let’s look at these permanent pool mosquitoes.

And it turns out in urban environments, we make great habitat for these, and what I’m getting at is, we see on the left we’ve got that, basically drainage grate, for rain runoff. Well, if you were to take that lid off and get down in that chamber, there’s this big tank or cistern, and water can sit in there. And even if it’s a dry year, if you think back to 2012, it was really dry, about 80, 90 degrees every day it seemed like, throughout June and July.

Even in these urban environments, there still would be some stagnant water, sitting in those runoff catch basins. And so these mosquitoes that like more permanent water, including Culex pipiens, a species you might’ve heard about because it can be associated with West Nile disease, that one likes to breed in these environments.

So, it’s a little bit ironic, you have a drier year but out of all the mosquitoes we see, you get a little bit higher proportion of these that can live in these types of environments. What’ll happen is if you have a really, really rainy year, it actually flushes the system out. It flushes these larvae away and they die.

So it’s a little bit counterintuitive, but you have a really rainy year, you’re going to have a lot of mosquitoes around, but they’re not this type, they’re from our next group we’ll talk about called the floodwater mosquitoes, and they’re not associated with West Nile, at least our main species isn’t. So, a little bit counterintuitive, dryer years we get more of these.

We can actually see a spike in West Nile cases when folks maybe have their guard down ’cause they’re not thinking about mosquitoes as much ’cause it hasn’t been rainy. And then our floodwater mosquitoes, and these were basically the mosquitoes we had big issues with last year, from the spring, because we had heavy spring rains.

And then when we had those monster rainfall events, in August and September, where parts of the state were getting a foot or more of rainfall, That set the stage for these. And with these floodwater mosquitoes, the eggs are actually sitting there already, out in the woods, in low-lying areas, just waiting for the rains to come. Once the water gets there, it doesn’t have to be there for very long.

If it’s nice and warm, these eggs can hatch and go through their lifecycle and emerge as adult mosquitoes in a week or less. So that water might only be there a week or two weeks, and then it’s gone, that’s enough to produce very, very large numbers of these mosquitoes. As I mentioned a moment ago, they’re not really transmitting things like West Nile, so that’s good, but these are fierce biters, and so when you were having picnics and barbecues ruined last September, it was these mosquitoes.

Things like Aedes vexans are an inland floodwater mosquito. One other interesting thing about these mosquitoes, they can fly very, very long distances. We’re talking five, 10, 20 miles, so in theory, you could kind of nuke your yard, if you could flip a switch, magically, all the mosquitoes disappear in your yard, but these fly or get blown in from 10 miles away, you could have more mosquitoes a short while later. So that can happen with these.

In terms of mosquito-borne diseases, just like ticks can transmit diseases, mosquitoes can transmit lots of things. Some we’ve heard of, but we really don’t have around here anymore, like malaria, although if you went back in the history books, if you were a farmer in Wisconsin in the early 1800s, we had issues with malaria here, until we drained wetlands and things like that and mitigated the situation, so historically, malaria was an issue here, it no longer really is.

Perhaps our biggest issue we hear about in the news, things like West Nile virus, is still around, making the rounds. Things like Culex pipiens can transmit it. We have some encephalitis viruses like La Crosse encephalitis. And then there are a few diseases you’ve probably heard about in the news. We don’t have problems with them up here but more tropical diseases: chikungunya, dengue fever, and Zika virus is the one that had popped up in the news in the last five years or so.

So with that in mind, let’s ask a quick question: Is Zika going to be an issue for us in the Upper Midwest? Well, the short answer is not really. We don’t have the right types of mosquitoes.

There are two main species of mosquitoes I think of when I think of Zika virus, Aedes albopictus, the Asian tiger mosquito, shown on the left, and then the yellow fever mosquito, Aedes aegypti. The map for that one is shown on the right. So these are really tropical species. They have been established for some time in the southern tier of states. Aedes albopictus on the left, that Asian tiger mosquito, in the last two years we’ve started picking it up in a few spots in Wisconsin.

We don’t really have any evidence that it’s established or breeding. How it’s getting here? It’s in the movement of tires to Wisconsin, so stores selling tires and things like that.

If you think about tires, if you wanted to invent an object that’s pretty much impossible to shake the water out of, it would be a tire, you can turn it every single way, you always have some water in there it seems like, and it’s a dark environment, and these species really love those environments to go to, to lay eggs. So in the grand scheme of things, yes, we’re starting to pick up this Asian tiger mosquito. It’s probably not surviving here or really reproducing.

We can see it’s in the southern states. In the grand scheme of things though, have we had Zika transmission by mosquitoes in the US? We have, but when you look at the map, it’s only in two spots, far southern Texas, and Miami area, far southern Florida, so having heard that, are we at risk up here in the Upper Midwest? Not really. Are things going to change with climate change as the decades go by? Possibly, but for the time being, we’re in a pretty good setting up here in Wisconsin.

All right, so mosquito management, what can we actually do to deal with mosquitoes and protect ourselves, and grandkids and kids, and things like that, a lot of different things? Just like with the ticks, we can manage our habitat. We can use personal protection and repellents. In some cases pesticides might be an option. There’s a few other remedies, urban legends and things like that, put this plant in your yard, do this or that, drink beer or somethin’ like that, to get rid of mosquitoes.

We’ll talk about that, most of those don’t really work. So in terms of managing mosquito habitat, we said mosquitoes need water. Some mosquitoes can fly in from water 20 miles down the road. Some have much shorter flight ranges, like that Culex pipiens, that does very well in urban environments. So, one of the things we can do around our yard is try and reduce or eliminate or minimize potential breeding spots, so any standing water in our yard.

That could be something like a tarp that’s catching a little bit of water and holding it there for a couple weeks. If we get rid of things like that, that can help. And you don’t need much water. If you have a bottle cap from a bottle of water, that’s enough to potentially raise a dozen mosquitoes or more in there. So tiny little areas can breed some mosquitoes. In some cases, it might be helpful to manage vegetation in our yard.

If we’ve got a bunch of dense vegetation, that can be resting areas for mosquitoes, so if we thin that out, get some more airflow, that may help to a certain extent as well. And another important thing is maintaining our buildings. If we have lots of mosquitoes around and our window screens have slashes and holes in ’em, they can get into our house.

But, if our house is sealed up well, and our porch and windows have good screens on it, that’s a way that we can have a physical barrier between us and mosquitoes. So, those are some things we can do in our yard. And just to reiterate on it, on this diagram here, I won’t go through all of these, but you can see, there’s a lot of areas you might not think about, that could be potential breeding areas for mosquitoes. It could be things like kids toys in the sandbox.

I remember as a kid having a dump truck in the sandbox, and the little seating area, where a person would sit in there, that would collect water. So, things like that can be enough water to raise some mosquitoes, so when you look at that chart: tires, pools that are neglected, gutters clogged up with leaves, that hold water. We know mosquitoes need water, and they like decomposing leaves. Well, you got the food and water right there for ’em.

So, if we reduce or eliminate those kind of things in our yard, that can help to a certain extent, reducing our local mosquitoes. Other things we can do: personal protection, basically putting barriers between us and mosquitoes. So things like clothing, I mentioned long-sleeved clothing for ticks, same kind of things with mosquitoes, long-sleeved shirt, long-sleeved pants, assuming it’s not ungodly hot. But, that can be a way to have a physical barrier so that mosquitoes can’t bite us as easily.

If they’re really bad, perhaps we need a mosquito head net to help keep them at bay. One other note about clothing, there is a little bit of a difference between colors. Mosquitoes and other biting flies tend to like darker colors a little bit better than lighter colors, so if you’re wearing a white shirt and person next to you is wearing a dark shirt, they might be more likely to go to the person wearing the darker colors.

Another thing you can do, simply if the mosquitoes are awful, maybe it’s best to stay indoors, or stay in the screened-in porch, is a way to have some physical protection. Otherwise, if you have that barbecue set up and scheduled, maybe you can rig up a box fan on your deck, get some air movement. Mosquitoes aren’t particularly strong flyers, if there is a decent wind, eight to 10 miles or more, they have a hard time actually getting to you.

So, a couple of big box fans set up might be enough to save that afternoon or evening barbecue. And then, using repellents again. A lot of the repellents for mosquitoes are the same ones we can use for ticks. Things like DEET and picaridin have a pretty broad range of repellent properties and work against a lot of different things. There are some other EPA-approved ones like oil of lemon eucalyptus, IR3535. There are also some area repellents.

There are devices that basically vaporize a repellent and help keep mosquitoes at bay, so just as an example, there are devices like Thermacell, and I’m sure there’s some other brands out there. But, those devices can also be used outdoors to help, mosquitoes, keep them away.

Some insecticides are available for mosquito control. You can have companies come do this as a service. The thing is, you need to understand the limitations of these treatments and be realistic. I view these types of treatments as a short-term fix. We talked a couple minutes ago about those floodwater mosquitoes. So, you could have, in theory, no mosquitoes in your yard. You took ’em all out of the equation.

Those floodwater mosquitoes from five, 10, 20 miles away, fly in or get blown in 10 minutes later and all of a sudden you got more mosquitoes again. So these are short-term fixes. Maybe your daughter is getting married two days from now. That’s a situation, yeah, go in, take out the mosquitoes. Understand it’s going to be a short-lived impact, and sometime after that, mosquitoes are going to move back in. So the notion that you have your yard mosquito-free all summer, that’s just unrealistic.

So, you need to understand what these products can do, but I do want to mention, there are some treatments out there for temporarily getting rid of the mosquitoes in your yard. There are also some potential non-target impacts. We hear in the news about bees and things like that. If you’re using a broad-spectrum pesticide in your yard that affects insects like mosquitoes, there’s a potential it might have impacts on bees and other pollinators, and other insects in your yard, too.

And then some other remedies I want to mention briefly. We hear about some of these things. There’s some truth to some of these, we know from research. Things like bats and birds can eat some. But, if you have a major flooding event, it probably doesn’t matter how many bats and birds are in your neighborhood, you’re probably still going to have some mosquitoes around. So, they can help, they’re probably not going to take them out of the equation if it’s a really, really rainy year.

In theory, there are CO2 traps, carbon dioxide. Mosquitoes will be attracted to that. They don’t seem to actually make much of a difference in your yard. Entomologists can use CO2 traps to monitor mosquito levels, but in terms of actually making a dent in their population, if you’ve got a major flooding event like we did last summer, probably not going to make much of a difference.

Then there’s some other things: sonic devices that are supposedly supposed to mimic the wind beat frequency of dragonflies and things like that and we don’t have evidence that those work. There’s no magic plants you can put in your yard that’re going to keep mosquitoes at bay. There have been studies looking at taking B vitamins or mint and vanilla and all these things, and we haven’t seen any major impacts of those.

With essential oils, some essential oils have some repellency against mosquitoes. It’s often very short-lived, though. So a DEET repellent might last four or six or 10 hours. For some of the essential oil products, they might smell lovely, they might only work for five or 10 or 20 minutes, so you’re having to use the entire bottle over the course of a day just to keep the mosquitoes at bay. One interesting thing, I saved drinking beer for last.

We do know from some research, if you drink alcohol, it can actually make you more attractive to mosquitoes.

(people laughing)

I suppose if you drank enough, you might forget about the mosquitoes, but at least having, or being a regular alcohol drinker can make you a little bit more attractive to mosquitoes. There’s a lot of factors that influence mosquitoes. Some of it boils down to the skin chemistry going on, if you will, our body produces a lot of chemicals on our skin, we’ve got microbes there, so we have this super scent, and certain things can alter that a little bit.

All right, we’re getting short on time, so moving on to some of our last biting flies, I’m not going to go into these as nearly as much detail. We’ve probably all bumped into deerflies and horseflies. A horsefly like the one we can see on our left, these can get to be very, very large size, sometimes an inch long or so. We’ve got a couple dozen species of horseflies in our area in the Upper Midwest. Many of them don’t actually like to bite humans.

They have a much stronger affinity for livestock, horses and cows and deer and things like that. But I remember swimming as a kid, really being pestered by some of those. So, horseflies certainly can bother us. Deerflies are actually a very close relative of horseflies, and they have a lot of similarities. They can be very, very fierce and pesky biters, and really pursue you for quite a ways. In terms of the mouth parts, they essentially have like a pocketknife.

They kind of slash you open and then see what oozes out, and slurp that up, so it can be very painful bites when they bite. One other important thing about deerflies and horseflies, they have a strong attraction to dark colors. We mentioned that with mosquitoes, that color difference. So, they like dark colors and they like moving objects.

So, when I go hiking with my wife and our two black labs, where do you think the flies go? The two black labs running around, so they do have that notion going with them. So, if you’re going out to habitat for these, I would maybe try wearing some lighter colors. We’ll talk about some other things you can do in a minute.

Another type of biting fly you maybe have bumped into, stable flies, and this I think of as more of an agricultural pest, they look like house flies, but they’ve got a piercing, biting mouth part. You can see it in the picture there. You got those two red dots, those are the fly’s eyes. That slender projection coming forward, that’s the mouth part, so they do have these slicing, biting mouth parts. When these tend to bite you, it tends to be on the lower legs.

And I’ve bumped into these in very large numbers, especially up towards Lake Superior. So you’re sitting on the lake shore trying to read a book, and these, they keep landing on your leg, and you swat ’em away and they come back up. So, really, really fierce biters. They breed in decaying vegetation: so fresh manure on a farm, seaweed, grass clippings and other decaying plants. They also can fly very, very long distances, in some cases, a hundred miles or more.

So you may be sitting on the shore of Lake Superior reading a book, they may have come from 50 miles down the road, and just happen to show up that day, so they can be very, very frustrating. Black flies, if you live near a river, you’ve probably bumped into these. These are teeny tiny little hunchback flies. They’re only a couple of millimeters long. So, we’re talking about 1/10 of an inch long.

So, not very big flies, they can emerge in very, very large numbers and really ruin your outdoor activities. There’s a bunch of species our area, but not all of them like to feed on human blood. There are some that prefer to feed on the blood of birds like loons and other species. And one thing to know about these is they are associated with actual good water quality, so if you see these around, that’s an indicator you’ve actually got some decent water quality in your area.

It’s things like trout streams, if you’ve got a trout stream or a river near you, that’s good habitat for black flies. Although black flies can travel some good distances as well, they can blow 10 or 20 miles away from their source. And then the last biting fly I want to talk about are biting midges. These are also called punkies or No See Ums. And even though they’re called No See Ums, they are big enough, you can actually see them with the naked eye, although they are small.

We’re talking about 1/16 of an inch or so, so teeny tiny little things, and boy do they pack a punch for their small size. Personally, I don’t react a whole lot to mosquitoes, and some of the other biting flies. These really get to me, you’ll look down, you really feel that pinch when they’re biting. And it leaves some pretty good red marks on me, whereas mosquitoes I typically don’t welt up much at all.

So to lump those last four I talked about, what can we actually do to deal with these? Well, that first notion, landscape management. Most of these species are associated with wetland areas, marshy areas and rivers and things like that, so we can’t really change that aspect of the landscape, so that’s kind of out of the equation. Some other things we can do though: personal protection and repellents. And also protecting our animals, I’ll talk about on this slide right here.

It’s a lot of the same things we talked about for mosquitoes: physical barriers, long-sleeved clothing, as long as it’s not too hot. If it’s really warm and the stable flies are out, and you’re on the shore of Lake Superior, maybe that mesh head net. Or, I’ve even seen a mesh suit you can wear to cover your entire body to keep them at bay, or put a blanket over your legs or somethin’ like that to keep them at bay, but that physical barrier can help. I also mentioned that color attraction.

They tend to like darker colors, so keep that in mind. Otherwise, the repellents can help with these, to a certain extent, so DEET, and some of the other repellents can help us. And also, if you have pets like dogs, there are some fly sprays available for dogs that can offer some repellency as well. So if the horseflies are really bothering your pets, my wife and I for example, we do spray our dogs before we go out on a hike.

All right, so just to wrap up today, I have a few slides left to talk about, things that sting. And I know I have a lot of folks in the audience that might have questions about these. We’re really talking about social hymenopterans: social bees, social wasps. These are insects that live together as a colony. The reason they are defensive is if you mess with the colony, you are messing with hundreds or thousands of their relatives, and so that really riles them up.

Versus, we have many species, thousands of species of bees and wasps that are solitary. That means each female, one female has an individual lone nest. She doesn’t have a nest full of relatives to defend, so those creatures tend to be relatively docile. In most cases, when folks call me, if they say I’ve been stung by a bee. “I was mowin’ the lawn, I went over a hole in the ground, “ground bees stung me,” those are really yellowjackets. I suspect a lot of stings are actually yellowjackets.

When it comes to social bees in the state, we don’t have many of ’em. And here’s a pie chart showing our bees in Wisconsin. We have honey bees, which of course are social bees. And honey bees, well, pretty much livin’ in a hive. With a beekeeper, occasionally we get feral colonies. So honey bee is one species of social bee, then we have about 20 or so species of bumblebees.

Bumblebees tend to be pretty big and robust, so if you bump into a bumblebee nest, you typically realize pretty quickly that they’re bumblebees, with their large size and fuzzy appearance. With that said, most other stinging things you’re going to bump into are actually some of our social wasps, from the family Vespidae. These are things like yellowjackets and bald-faced hornets, which is technically a type of yellowjacket, and also paper wasps.

There’s lots of different species, dozens of different species of these in our area. They all have very similar biology though. They start colonies from scratch each spring, so the colonies actually die out in the fall. With that said, if you go out to your yard today and find a yellowjacket nest up in your tree, nobody’s home. They’ve all died out for the winter. The only members of the colony that survived the winter are females. They find sheltered spots, they spend the winter.

And, those females have made it last year, they will be the new queens this spring, and establish new colonies. So at first, she’s doing all the work. She’s got to build up the colony, raise workers, eventually the workers take over the foraging activity and she stays there and lays eggs for the most part. So they don’t reuse these nests from year to year. There’s a good reason for that.

What if last year’s nest died out from a disease? You don’t want to move back into that nest to start up your colony this year, ’cause that same disease may still be around, so those nests don’t get reused. We’ve got our yellowjackets, and there’s lots of different species of these. They look something like this on the left, a black and yellow striped body. Some species build aerial, kind of paper mache type nests. Some yellowjackets build ground nests, and they’re not great diggers.

They go to pre-existing cavities, like a chipmunk burrow, and make their nest there. So again, when someone tells me they took their lawnmower over somethin’ and ground bees got ’em, it’s these ground-nesting yellowjackets. Some of the species in this group, like German yellowjacket, also are fond of nesting in hollow cavities. That’s the species that will get into your soffit area or into your wall voids of your house. We’ll talk about how to deal with those in just a minute.

Bald-faced hornet is a special type of yellowjacket, but it’s got a different name of bald-faced hornet. They also make very, very large papier mache type nests. So, we’re talking about, you see the basketball-sized nest, that’s probably this species. They’re black and white instead of black and yellow.

And then paper wasps, so these ones still make a paper mache type nest, but it’s open construction. You can look in at your soffit area, and see who’s home, so to speak, inside that nest. You can actually see inside of it. What can we actually do about wasps? Well, remember, they’re annual colonies, they died out in the fall.

So, if I don’t discover a colony up in my tree until the leaves fall off in fall, I know they’re going to be dying on their own very, very shortly, and I can just wait ’til the frosts come and finish ’em off. We can also avoid them, in a lot of cases, these insects are fairly non-aggressive unless you get very close.

So, if I have a tree in the back 40, back corner of my yard that’s got one of these nests in it, I may just leave it, if kids and aren’t going back there, because those wasps are actually really good predators. They’ll come into your garden and pick off cut worms and hornworm caterpillars and things like that, so they do some good things for us, too.

Otherwise, physical exclusion, if every year I seem to get issues up in my soffit area, if I go up there with a caulk gun and seal up potential entrance points, that’s going to stop things before they establish a nest. Same kind of thing with lawn nests, if you have chipmunk burrows around, this spring, fill ’em in, before those female queens start establishing a new nest. That’ll prevent it before it comes.

Otherwise, when it comes to insecticides, we can go to the hardware store and buy an aerosol can of wasp spray. Those can work for exposed nests. So those paper wasps’ nests, you can look up and see the nest right there. We can spray that and take it out. The problem is when you have nests that are inaccessible, they’re down in the ground, or they’re in a soffit area, that spray, the droplets tend to settle and stop working relatively quickly. and they don’t get a whole lot of exposure.

What’s much better in those cases, and it might be the same chemical ingredient, but a dust or a powder, because what we can do is use a bulb duster, you could even use an empty condiment bottle, like an old mustard bottle. So, you can puff that powder in there, get it to flow in, then as the insects come and go, they track that material into their nest. That tends to work much better.

Also, for ground nests, there are some newer products, it looks like a WD-40 can with a straw, it foams up and expands, so you can spray that in there, it expands, and that can work pretty well against ground nests, so keep in mind, you have to pick your product correctly.

And with that, I am just about out of time. I think I have a few minutes for questions. Thank you for your attention. The last thing I want to mention, I’ve got my contact information on this slide. If you’re looking for handouts from today’s notes, if you go to my website, and I’ve got the web address right there, you can download those to your device or print ’em off at home, so those are available.

(people clapping)