The Intriguing Life Histories of Mosquitoes
Welcome to tonight's community lecture. We have a very interesting lecture tonight on mosquitoes, which is a little late in the season, but we'll go with it anyway. Some of you still have some of those in your cars and in your basements, and every now and then I find one in my bedroom. But having said that, tonight's speaker is Jamee Hubbard.
She has a Bachelor of Science degree in Biology from the University of Central Missouri. And she has a Master of Science degree from Auburn University, where her research focused on cultural management of green June beetles in pastures. It turns out she's been a faculty member at Stevens Point since 2005. She teaches the Introduction to Animal Biology course.
She teaches Entomology and Ecology and Evolution. For the past few years, she's returned to her love for mosquitoes and has been investigating the mosquito species complexes in various habitats in Wisconsin. She is also married, has two young boys. They are happy to collect mosquitoes, and I understand they might be down in the computer room tonight.
And her husband is here with us as well. Jamee's been a great colleague, she's also a curator with our Museum of Natural History, and usually has one of the most, let's just say, active sites when we do our collection crawl in March. There's lots and lots and lots of kids around that love to see the bugs. It's my pleasure to introduce Dr.
Jamee Hubbard. Her topic tonight is The Intriguing Life Histories of Mosquitoes, Portage County. Jamee? (audience applauding) Thank you.
And thank you so much for coming out. I know there's a lot of competition with other things going on in town, so I really appreciate you coming to my talk. So my talk is The Intriguing Life Histories of Mosquitoes of Portage County. And this is actually a list, and I think it's actually outdated now, a list of current and possible species in Wisconsin.
We have 56 species that we know of that live in Wisconsin. And in parentheses there you will see PS and PW and PN. Those are actually Possible Northern, Possible Southern, and Possible Western. And we may even have some Possible Eastern species.
When you look at maps of species distribution, sometimes this species end at the state line only because the surveillance of those mosquitoes has ended, like we're not surveilling for them in this state, or we just haven't found them in this state. But probably they will come across the state line, so anything that may be in Minnesota, for example, probably has, like on the eastern side of Minnesota, probably has made its way over into Wisconsin. It actually has been since the 1960s, was the latest big-scale survey of mosquitoes in Wisconsin. There was a bigger all-state survey of mosquitoes in Wisconsin in the 1940s.
And then in the 1960s there was a large survey of mosquitoes in northern Wisconsin of adult and larval mosquitoes. But since then there really hasn't been a survey of mosquitoes that has focused on, basically, on just what mosquitoes do we find and what kind of habitats. Most of the surveys of mosquitoes has been focused on mosquitoes of medical and veterinary importance and mostly in urban regions, and not so much in rural regions. And so I took up the I was here getting bitten by a lot of mosquitoes.
I developed an interest in mosquitoes, actually, when I was in graduate school and thought I would go on to work in mosquitoes for my graduate program, for my Ph.D. program, but I ended up doing something else. So when I was here kind of looking for what kind of research topics might be interesting, as we're walking down a trail being eaten alive by mosquitoes, I was like, aha (laughs) I can go back to my love for mosquitoes and look into what kind of mosquitoes do we have here. And when I found out there really wasn't much in terms of ecological research on mosquitoes, I got really interested in this topic again and thought maybe I should look into this a little bit more.
So that's what I've been doing for the last few years, since 2012. So I'm going to talk a little bit about the biology of mosquitoes. Believe me I won't talk about all 50 mosquitoes, I'm really just going to be talking about specific kinds of mosquitoes in Portage County that I think are of medical and veterinary concern and are of interest to me. But before I get into talking about what kind of mosquitoes we have here, I wanted to touch on the biology of mosquitoes.
So I'm going to start here with the female that is laying her eggs. So the female will lay her eggs in, on, or near water. This is mosquito is a Culex mosquito, and she's laying what's called an egg raft. The egg raft will sit there for a couple of days, and this depends on the temperature.
They're very dependent on temperature. After a couple of days, two to three days, those mosquitoes, the mosquito larvae will pop out of the bottom and just swim away. So then they will develop as larvae. And here are a couple of larvae right here.
And when they are developing, they actually have, most of them will have this air tube, that we called a siphon. And the siphon breaks the surface tension of the water and has little, creates a little hole in the surface of the water that they breathe through. So they're actually going to breathe air, unlike many other larval insects that in the water they're usually breathing through their exoskeleton. But these are actually going to breath the atmospheric air.
And they have these mouth brushes you can kind of see the ends of them right here in the larvae that you see on the right that they use to collect their food. And so most of them are going to be filter feeders. They're going to be filtering out organic matter, various kinds of decaying leaf matter. Some of them may be feeding on small or micro organisms.
Some of them feed on amoeba. Some of them feed on algae. So they're going to be filter feeding. Some of them are actually predaceous on other mosquitoes.
And I've got one I'll talk about a little later. So they spend probably about five, maybe three or four or five days as a larva and they'll go through different larval stages where they have to grow and then they'll have to shed off their exoskeleton to get larger. So they'll maybe go through about three of those stages. And then eventually they become a pupa.
That's this guy right here. This is a non-feeding, and in this case, a mobile stage. By the way, the larvae are called wigglers because they wiggle around in the water. If you disturb the water they'll wiggle down a little bit deeper to get away from you.
These guys are sort of cylindrical-shaped and they're called tumblers because if you disturb the water they'll tumble down because of their shape. And they have on the tops of their bodies these little......they're breathing tubes. There's a pair of them. That they're called trumpets in this case.
And they look like little, the ends of trumpets and they stick them out of the surface of the water and again break the water surface tension and they breathe through those trumpets. You can kind of see the legs developing here on the inside. Insects that go through this kind of development have to have this sort of non-feeding, longer-term stage of development where they're not doing anything except for developing because they're going to go through something that looks like this larva to something incredibly different, that looks like this. So after a couple of days of being in this pupal development stage, they will then emerge as an adult.
You can see this adult coming out. This is called eclosion. They're going to eclose from this pupal case and then, this is actually a female right here, and then she will fly off. And she is going to go off.
Most species of mosquitoes, they are going to go find a mammal or bird host or perhaps even a reptile, but usually mammals and birds. And they're going to feed. And it's only the female that is going to feed on blood. And she needs that blood as a protein source for her eggs.
Her eggs are mostly already developed, and she's going to take that blood meal and then she's going to go off for perhaps a few hours, 12 hours maybe up to a couple of days, and process that protein and develop the yolk of her eggs. And then she will go off and lay her eggs. And she'll lay maybe between 20 to 100 eggs, depending on the species and depending on whether she gets disturbed or not. The male, by the way, before I go on to the next page, the males do not feed on blood.
Usually they're nectar feeders, so they're going to find a plant and they're going to feed on nectar. They're after a sugar source that will give them the energy that they need to fly around and find females. So they don't really have a need for the blood. So these are some examples of mosquito eggs.
I said that they are going to lay their eggs in, on, or near water. And it really depends on the kind of species of mosquito that they are. So these are, this is an egg raft that I showed you on the last slide, these are laid by a genus of mosquito called Culex. So she lays these little egg rafts.
I actually have some egg rafts that I collected from my own yard over there. She'll lay them on surface of the water. They don't like water that's free-flowing too much; they like more stagnant water. So if you leave a container, like a tarp or something that holds water on the outside of your house or a canister or something that has some organic matter in it, they'll probably lay their eggs on there.
It looks like a little piece of charred bark curled up. So if you see something like that on the surface of the water it could be mosquito eggs. And then these eggs up right here are Anopheles. The mosquitoes in the genus An opheles, they lay eggs, individual little eggs with little floaties on them on the side.
That's what these clear structures are on the side of those eggs. So they lay them individually on the surface of the water. So they're really not, these two kinds of mosquitoes are really not dependent on how much, they're going to have to lay their eggs in a place where there's water all the time. They're not really dependent on rising and lowering of water or whether the water is going to try out or not.
They're always going to lay their eggs in a place that's most likely to have water all the time. These eggs, on the other hand, are eggs of the mosquitoes in the genus Aedes. They are going to eggs right above the water surface. So they usually lay their eggs just above the water surface either in a tire, for example, or in a tree hole, or maybe in, if you have an ephemeral pond, a little patch of water that dries up often, they may lay their eggs around the outside of that.
And so what these are going to be doing is they're going to lay those eggs, and those eggs are going to sit there and kind of go through this developmental period. And then they're going to go through a pause. And they're going to stop and they're going to wait until the water rises again. So the next time it rains and the water comes up, the lack of oxygen around those eggs when the water covers them is actually going to induce those eggs to hatch.
So mosquitoes, you may hear the word floodwater mosquito. Floodwater mosquitoes are these kinds of mosquitoes where they're going to lay their eggs out in places and wait, when we get a lot of rain and the rain covers those eggs and then those eggs will hatch. So different kinds of mosquitoes are taking advantage of different kinds of habitats and they have different ways of getting their larvae into the water. These are some typical mosquito habitats.
So this is walking through Schmeeckle Reserve you see something that looks like this. These are ephemeral ponds that are short-lived. Patches of water, small depressions that don't drain very well and have lot of organic matter in it. So these are, when it rains, this is where we're going to get our mosquito population that comes out after it rains, this is where were getting them from.
These places right here. This is a tree hole. So tree holes will fill up with water and so Aedes mosquitoes, which are tree-hole mosquitoes will lay their eggs in there. And their larvae will develop as soon as they get covered up with water.
Drainage ditches like this are great places to find mosquitoes. Tires are great places to find mosquitoes. So it's required in most states for people that are going to store tires like this to slash the tire in half so that it doesn't hold water, so it doesn't breed mosquitoes. If you have a tarp in your yard covering your wood and it has any depressions in it at all, it will hold enough water and leaves falling down off the trees will hold a little bit of organic matter in there, it will hold enough water for the larvae to develop in.
So just a small depression in the tarp. And then boggy areas like this. You can see that the water isn't very free-moving right here and it's collecting organic matter. So you would find mosquitoes in a place like, along these edges right here.
They like to be in kind of covered places where there's vegetation or something that they can hide around. I wanted to talk a little bit about how we identify mosquitoes. So we can look at the adults, which are fairly easy to catch. And we can look at the larvae.
The thing about the adults, catching the adults, is that if you put out a trap for adults, you might be drawing adults that are not necessarily breeding in that area. They may be hanging out and they may be taking a blood meal, but they're not necessarily breeding there. Whereas, you know if you are collecting the larvae you know you're getting them in their breeding site. Both of them have their challenges.
This is one of my students, Dan Philips, and one of my other students, Alana Fish, is here. She has just recently joined my lab and is doing some mosquito ID for me. I cannot thank her enough because it is really a grueling task for anybody, even for me it's time-consuming. What we are looking for in the adults is we're looking for presence of bands on the legs or not.
And how wide those bands are, or if they are super-wide or if they're somewhat yellow. We're also looking for banding on the abdomen. These bands are the result of different colors of scales on the body, and sometimes those scales look more like hairs and sometimes they look more like broad scales that you might find on the surface of a butterfly. We're also looking for the presence of different patterns or colors on the thorax right here.
Perhaps even a stripe on the proboscis, the feeding tube. So those are some things that we're looking for when we're ID'ing adults. When we're ID'ing larvae, it can be easy, but it can be really tough if you don't have a great microscope. One of my microscopes is good, the other one not so great.
In a lot of fly taxonomy, and mosquitoes are flies, we use hairs. It's called chaetotaxy. We use hairs and the position of the hairs to identify them. So what we're looking for in these mosquito larvae is sometimes were looking for certain kinds of little hairs and scales back here on the breathing tube, up here on the head, you have to sort of count the number of hair groups on the head, so it can be really a daunting task.
I actually brought some specimens with me that after my talk you can take a look at. I think the library's open until eight, so hopefully I can get done really fast and you guys will have some time to look at stuff. I have two of my favorite mosquitoes under there, but I've got some larvae that we can look at and various others. I've got my book, this book right here that's like the Bible of identifying mosquitoes, both adult and larvae, over there so you can take a look at what we have to use and the terminology.
The terminology is quite crazy, as my student Alana is finding out, but once you get the hang of it, it's not so bad. It goes a little bit slower, or faster. Why do we care about mosquitoes? Some are of medical concerns so that, I think, a big concern of public health organizations and the public in general.
But I think that the public has the understanding that all mosquitoes are of medical concern, but we actually only have a few mosquitoes in Portage County and in Wisconsin that are really of medical concern. Some are a nuisance. This is the second biggest reason people don't like mosquitoes, because they bite. I've gotten kind of used to it, so I don't feel them as often.
They're important as food for fish and other organisms. Not so much bats like we tend to think, but definitely for fish. Mosquito populations change over time, and this can have an effect on all of these things up here. So some mosquitoes of medical concern, mosquitoes that are a nuisance, and mosquitoes that serve as food sources.
So they can change. These populations, these different species can change as we see changes in our waterways and our water quality over time. So as urban environments spread out and we see changes in, we see drainage of our marshy areas and we see less, fewer woodland pools, that's going to cause a change in the different kinds of mosquitoes because some mosquitoes are going to feed in places where the water is cleaner. Some mosquitoes are going to feed in places where maybe the water is a little more full of organic matter.
Some mosquitoes are going to feed in places that are less-- are more likely to be less polluted. Also, we see newly-introduced mosquitoes. We have a mosquito that I'll talk about that was introduced or was found here for the first time in 2004. It was introduced in the United States, they suspect, around 1999, called the Japanese rock pool mosquito.
And then climate change can cause a change in the types of mosquitoes that we see in Wisconsin. As it becomes warmer and we have less snow, we have fewer mosquitoes that we call the Snow Mount mosquitoes. We also have a longer breeding period of time if we have a longer summer time and it's warmer later in the season, we'll have a longer breeding period. That means a longer period of biting and more of an opportunity to spread disease.
And another reason to care about mosquitoes is because, well, I think they're really interesting. I got interested in mosquitoes because of the incredible biodiversity that's out there and just how very different they are from each other. So I want to talk first about mosquitoes that are of medical importance in Wisconsin and in Portage County. These are the different diseases that are transmitted by mosquitoes in Wisconsin.
So you can see there is not actually very many diseases here in Wisconsin. We have the potential to get diseases that we see farther south, but we would have to have those southern-ranging mosquitoes that are more likely to carry those diseases up here and we just don't have that yet. But as climate changes we may see that in the future. Some of these are pretty minor, like California encephalitis.
Eastern equine encephalitis does come around every once in a while. These encephalitis viruses, which are viruses that cause brain swelling, tend to be cyclic, so they'll move through across the country and then things will settle down and they'll move through again. Western equine encephalitis, I've actually never seen Jamestown Canyon encephalitis virus here, but supposedly it is. La Crosse encephalitis virus.
St. Louis encephalitis virus hits Wisconsin occasionally. West Nile virus. That's the one that everybody's concerned about because we still have it and it still shows up in our mosquito populations and in our horse populations, and our bird populations every year.
So once we got it it just kept hanging around. And I know the people in the back really can't see this very well, it's not very dark. I just copied it off their website. These are the positive West Nile virus cases in 2015, as of September 2015.
And there were several bird species that they found to be infected with West Nile virus. There was one horse case. There were 15 mosquito specimens that they found West Nile virus in, and zero confirmed human cases, and three probable human cases. The deal with that is that it's really actually hard.
Unless you are elderly or you have a compromised immune system or for some other reason you have a compromised immune system and you get really ill from it and you have to get all kinds of tests, usually you get symptoms that are more like flu symptoms. And so you may feel like you have a headache, you have body aches, you have fever, you're hot. You may actually feel like you just got the flu or a really bad cold. So oftentimes people may have actually been infected with West Nile virus and just didn't know it.
So we don't know actually how many human cases there were. We know that there were three probable human cases. There was one death that came from this probable pool and one hospitalization. And in 37 counties reporting West Nile virus activity.
And here in Portage County we had no human activity. So we had some non-human activity, so we probably found those in bird specimens, that West Nile virus in bird specimens. But you can see that in Marathon County, they had non-human and human activity cases of probably those probable cases. One of those probable cases probably came from Marathon County.
So of the medically important mosquitoes in Wisconsin, we really have three genera of mosquitoes. We have mosquitoes that belong to the genus Culex, and the genus Aedes, and the genus Ochlerotatus. And Aedes and Ochlerotatus are actually very very similar. They actually key out together in our key.
And sometimes the taxonomists switch those names back and forth, so they may jump into one genus and then the other. So they're really kind of like the same genus. Again, it's hard to see this in the back, but this is a list of the mosquitoes that carry West Nile virus, that they have found West Nile virus in Wisconsin. Quite a big list of mosquitoes.
But to be honest, just because it's carrying West Nile virus does not mean that it can actually transmit West Nile virus, that virus. Mosquitoes are not affected by the virus, they're just passing it from one species to another, so from birds to humans. And they just may not have enough viral particles or viral entities in their bodies to be able to pass those along to another host. So really the biggest one that we have to be concerned about here in central Wisconsin is the Culex pipiens and Culex restuans complex.
These are the Northern House Mosquito, well, the Culex pipiens is the Northern House Mosquito. It's very difficult to tell these two apart, so oftentimes they are just lumped together. This is the Northern House Mosquito, Culex pipiens, and it's identified, it's a relatively small mosquito and I brought one with me. It's really kind of tan, it's kind of a boring mosquito in terms of the way it looks.
It's tan-ish, red-ish. It's kind of fuzzy up here on the thorax. Has a black proboscis. All black legs.
And these just straight stripes across, white scales across each abdominal segment, and just a little tuft of silvery scales on the side, not much. But it is kind of cute, too. It's boring and kind of cute at the same time. It has this little truncated abdomen, so we kind of, when I see one I'm like, "Oh yeah that's a Culex." I can tell right away just because it has this sort of rounded, squared-off abdomen.
You often find these in houses, which is how it got its name Northern House Mosquito. So they will come in through little holes in your screens. And they're an avian species, so they will feed on birds predominantly. And they will get in so they will be up in the canopy of your house, and then they will find a little hole in your screen and come in in the summer or early fall.
And then they will find a human host to feed on, too. So primarily they prefer birds to feed on, but they will feed on humans as well. And that's how we get West Nile virus from those mosquitoes. Because they do occasionally feed on humans.
Other species that primarily feed on birds will not really feed on humans. Another one that's of interest is Aedes triseriatus. This is a really distinctive looking mosquito. It has this what I call like a fur, a stole, a fur coat over its thorax, shoulders right here, of white silvery scales.
It has these really cool triangular patches of scales on each abdominal segment. And their legs are very black with kind of some stark white on them. And they have a pointed abdomen right here. And well just pretty much black wings.
But you can definitely see this white shawl or stole over its shoulders. And this one feeds on large mammals and rodents as well. And it is a vector of La Crosse virus that we do get occasionally through Wisconsin. But it is also, we have a lot of them, so they're nuisance mosquitoes, too.
And also predominately they feed on, since they feed on large mammals they feed on humans pretty readily. Another one that we have here that is of medical concern and nuisance concern is Aedes vexans. It does have some white scales on the side, but what we see on these are these scallops on the back, so these sort of half-moon-shaped scales down each abdominal segment and a pointed abdomen. It's more of a brown-ish mosquito.
It has a really nice look to it. Another thing about this is that they have these stripes on the legs as well. So you're looking for the scallops on the abdomen, I'm sure most of you are not going to get close enough to look at them, but I will just, like, barely tap it and then I will go, "Oh, I see what mosquito that is." And then again looking for stripes on the legs. And these are mosquitoes that are going to be abundant after heavy rains.
They are one of our floodwater mosquitoes. After heavy rains these are going to be some of them that come out. And these, again, are also going to feed on large mammals and rodents and humans. They are a vector of dog heartworm, so they are really big medical concern in Wisconsin, in Portage County for that.
They are found in those temporary ephemeral pools. Again, a really bad nuisance mosquito, and we have tons of them, so these are going to be one of the predominant mosquitoes that I collect. Another really cool mosquito. Coquillettidia perturbans.
And you can tell by the name perturbans that these are probably going to be bad nuisance mosquitoes. And they are. Since we have a lot of sort of marshy areas around here and a lot of cattails, we're going to find a lot of these mosquitoes around here. The common name of these is the cattail mosquito, or at least I call them.
I don't think they really officially have a common name. What's really, this mosquito was really neat. So one of the things that's really neat about them is that they are super-striking under the microscope. They have these black-and-white, sort of brown-ish black-and-white scales, and the scales are really big and sort of teardrop-shaped.
And they have those all along their wings, all over their legs, all over their whole body. And then their legs have these really striking wide stripes on them. And then they have a white stripe on their proboscis here. Another thing that's really cool about them is that their larvae instead of coming up and feeding, spending their time breathing at the surface of the water, like breaking the water surface and breathing there, they have an interesting siphon that's a saw-shaped siphon.
They saw that into hollow-stem plants and roots like cattail roots and they breathe through the plant. So they are actually able to kind of evade detection by potential predators like fishes by hanging out right on the roots and breathing through the roots. And actually their pupal stage has a saw-like trumpets act too, and they will saw those into the plants and they'll just breathe hanging onto the plant roots. It's a really great place to hang out if you're trying to keep from being predated by fish, for example, or frogs.
So I think they're really cool for that reason. They also feed on birds and mammals. And they're a vector of Eastern equine encephalitis virus. A fairly common virus that we get here in Wisconsin in our horses.
But they're everywhere, so they're a nuisance mosquito as well. And they are voracious biters. So I want to switch from these medically important mosquitoes to some mosquitoes that I think are just really super-interesting and really aren't of really medical concern. So one of them is the one that I said was introduced into Wisconsin, first introduced into New Jersey and then quickly, within about four years from 1999 to probably before 2004, made it into Wisconsin.
I know by 2000 we had them down in Kentucky because I was identifying them there in Lexington. (coughs) Excuse me. We found them, they were found here for the first time in 2004, a year before I came here. They're really striking mosquitoes.
They actually resemble the Yellow Fever Mosquito. Let's see, I'm thinking off the top of my head, but they actually resemble the Yellow Fever Mosquito but we don't not have that up here. The Yellow Fever Mosquito has a white lyre shape on the back of their thorax right here. The Japanese Rock pool mosquito, the Ochlerotatus japonicus has sort of a broken yellow lyre.
It is a relatively large mosquito. And it also has these yellow-ish, they kind of look white in here, but they're more yellow-ish white bands on their legs, and tufts of white-ish-yellow scales on their body. So they kind of have more of a yellow-ish-scaled appearance, but very striking. These also feed on birds and mammals, and they have the potential to spread quite a few diseases.
We don't know for sure that they're spreading diseases here in Wisconsin, but they have been found to carry quite a few diseases and have the potential to spread those diseases. They're actually rather large and very aggressive biters during the day, and they're aggressive feeders as larvae because their larvae are pretty large too. And they're actually out competing with some of our native mosquitoes and taking over habitats that our native mosquitoes are usually found in. These were introduced from Asia.
And they're found in standing water. They're called the Rock Pool Mosquito because like the smallest little depressions of water. So these are mosquitoes that you can easily find in the little depressions in your tarps. I found them in our backyard in our tarps and in various small, little pools of water.
This one you've probably seen over the last couple of years, maybe before that, but I know a couple of years ago it came out pretty predominantly late in the season. It's called the "Gallinipper," that's one common name of it. Psorophora ciliata is the species name. It is huge, obviously, and it's distinguished by these tufts of black scales that stick out.
They're like, really hairy on the legs. Otherwise, it's mostly just brown-black, but you just cannot miss this mosquito, really. It feeds on large mammals. It's a very aggressive biter.
Here we don't get so many, at least I haven't experienced that. Down South in Alabama and Kentucky they would just swarm you at night. They don't care whether you have insect repellent on, they don't care whether you have jeans on. They are so big that they can just bite right through the jeans.
This is their proboscis right here is huge. Predominantly, we're finding these in the Southern regions, so though they do creep up here into Portage County. And that is one of the reasons why we don't find them readily throughout here, but we do find them occasionally. I've seen them at my house just downtown Stevens Point.
This is the size. They're about an inch in length. They're huge. And then compared to a normal mosquito, they are twice the size.
We actually have a much larger mosquito in southern, in the Southern US called the Toxorhynchites mosquito, but it does not feed on humans. This one however is big enough to give you a pretty good wallop. And again, it doesn't care if you have jeans on, it'll just bite right through. So it's a nuisance mosquito, not so much of a medical concern, but I think it's cool because it's giant.
Another really cool one is called the Jewel Mosquito, or Uranotaenia sappharina The name sappharina implies that it has something to do with sapphires, and if you look at the mosquito under a microscope when the light is shining on it, it has these iridescent scales on the body, on the sides of the thorax, a little bit on the wing, a little bit behind the head, and right here on the coxa, the upper part of the leg. And a stripe down the back. And it's just absolutely beautiful mosquito. It actually doesn't bite humans, so I like it even more for that reason.
And it has never been able to be coaxed into biting humans the lab. And it may actually not need a mate to reproduce. They're not sure, for sure about this one, but it may not need a mate to reproduce. So it's pretty cool.
And we do have that in Schmeeckle Reserve. And this next one is the Pitcher Plant Mosquito. It's Wyeomyia smithii and it only breeds in pitcher plants. And one of the former UW-SP faculty members, Vince Heig, brought in some pitcher plants from his bog.
We dumped them out in a couple of containers over here, and we found mosquito larvae in there. So you guys after this talk will be able to take a look at those in those cups and see the little wigglers wiggling around. There's other fly larvae in there, I'm assuming they're fly larvae too. They're kind of elongated and they look like worms.
So those wouldn't be the ones you are looking for, but the ones that are wiggling kind of back and forth like this really quickly are the ones, are the wigglers. They only breed in pitcher plants, which can have a high acidity, and they don't breed anywhere else. There's no other mosquito that I know of in Wisconsin that will breed in these pitcher plants. I'll find other insects and other invertebrates in there.
And they're distinguished by their all-black, I mean they're all black, their thorax, their abdomen, their legs, and they're very small. What else do I want to say about those? They're not going to bite humans or animals either, so they don't feed on any animals. And they are autogenous, which means that they don't need a male to reproduce.
And because they don't feed on animals, they're actually going to get all their nutrition as a larva. Oh, I know what I was going to say! The larvae feed on amoebas in the pitcher plant, so that's kind of interesting about them. They're not necessarily feeding on organic matter, but they're feeding on other living organisms.
I know this is very dark. I thought I had a lighter one, but I couldn't find it. But anyway, this is a mosquito, a larger mosquito larva from that pitcher that I dumped out in Hunt Hill Audubon sanctuary up north in Washburn County. Another really neat mosquito that we have here is Psorophora ferox, the White-footed Mosquito.
And it's identified by its little white booties on its hind legs. I actually, my first summer here at one of these land on me. So, they do bite but they're not really prominent biters. They are recognizable by, they have sort of an iridescent bluish-purple abdomen and a gold-ish thorax.
So this bluish-purple and the white booties really give this one away. They kind of have a bluish, purple-ish iridescence to their legs as well. And then these white patch, triangular patches of scales on their abdomen. They are a biter.
I haven't seen a whole lot of them, but they're a biter. One pretty cool piece of information is that in Colombia, thankfully not here, but in Colombia they carry the eggs of the human bot fly. The way that works is the human bot fly needs to get his bot flies to a human, but humans are pretty good at swatting away flies on us. So what they're going to do is they're going to intercept a blood-feeding insect, and usually it's a mosquito or some other kind of blood-feeding insect.
So the human bot fly, which is pretty big, it looks like a housefly, kind of, a white-ish housefly that is really big. It intercepts the mosquito, it tangles with it, in the process it lays its eggs on the underside, the ventral, or underside of the abdomen. And then the mosquito, kind of dazed, flies away, finds a host, a human host, and she takes blood meal. When she fills up with blood, that warm blood in her abdomen melts the eggs of the human bot fly and they fall off of the abdomen and onto the human.
They immediately hatch out and burrow into the skin. That's how you get the human bot fly. So you can thank the mosquitoes that are feeding on you. So protect yourself from mosquitoes when you go to Colombia.
Another interesting one is Ochlerotatus provocans. This one I found for the first time, we found it as a larva this last year. One of my students was out collecting and collected this. This is a snow-melt mosquito.
So we here have snow, and there are some mosquitoes that actually prefer the clean, cleaner water and cooler water that's more oxygenated in the early spring. And so they will be the first ones to come out. So this is one first earliest to emerge. It's kind of a golden on the thorax and brown-ish on the abdomen, with these white, triangular patches and dark legs.
But I thought it was really neat because we find this in snowmelt of woodland pools and ditches. So we got some of these in Schmeeckle Reserve. So I want to just briefly talk about my research. I have a few more minutes here.
When I came, when I decided I was going to work on this I wasn't sure how I was going to divide this data up to investigate mosquitoes. And what I was most interested in is what mosquito complexes do we find in different kinds of habitat. Not so much the medical importance of them, although that's interesting to me. I was really more interested in what mosquitoes do we find where.
And I'm interested in putting together a checklist of mosquitoes and actually an identification guide for the layman, for people who are working for, like, the county health department and such. So a student was working with me and we decided that we were going, she actually decided this would be a good idea and I was like, "You're right. This would be a good idea." She found this division of the state that the EPA put out, the Environmental Protection Agency put out, that divides the state into 27 eco-regions. What these are are regions divided by their ecology.
So what kind of plant vegetation do they have? And also their geology, which is really important for mosquitoes because mosquitoes lay their eggs in water. And what's going to depend what water's going to be there? Whether you have good drain soil or poorly drained soil and whether you have waterways there, right?
So those two things are super-important for the development of mosquitoes. So we decided to break the state up by these 27 eco-regions and we haven't gotten very far. But Hunt Hill Audubon Sanctuary in Washburn County and up here in, I can't think, Tree Haven. We've been sampling there, I was sampling there and here in Portage County.
That's about as far as we've gotten. I plan to get data from other places, not necessarily doing all the collecting myself, but it's slow-going. So that's where we're headed with that. This is how I trap the adult mosquitoes.
This is a trap, and I've got one on the wall hanging up over here. It's called a CDC miniature light trap. And we bait it with dry ice, which releases carbon dioxide. Carbon dioxide is really heavy so it falls out of a hole on the bottom of this cooler.
It flows over the top of it, there's a fan in here with a light. So the incandescent light attracts mosquitoes. The carbon dioxide, which is what the mosquitoes are homing in on to find you, will attract the mosquitoes. The heat of the light kind of draws them in.
They get sucked into a fan and into this cup right here. And here's a trap out in a habitat out in Bancroft. And a close-up here you can see the carbon dioxide flowing out of the cooler. And here's a catch, this one actually up in Hunt Hill.
This is full of mosquitoes right here, so that's a lot. Yeah, I didn't like standing out in the woods putting that trap up. I got covered a lot in mosquitoes. This can be a typical nice collection for one trap.
So you can imagine why this is slow-going. To identify all these mosquitoes from one trap, and I put out four traps a night in four different habitats. And I do this, I try to do this once a month to get some seasonal data up in Hunt Hill because they just have so many mosquitoes. Here I was doing it every other week.
In terms of Portage County, these are the mosquitoes that we identified so far. These are the species, in red, that we've identified so far. So we have mosquitoes from every genus except for Orthopodomyia, which I'm pretty sure we have here. The Psorophora ciliata, that's the big Gallinipper.
And this is the white-footed mosquito. I did not get in research samples, but actually collected feeding on me. But otherwise, the rest of these came from, that one didn't come from research samples either but the rest of them came from my research samples. But we have more to go.
Lots more to go. So I'm sure that we're going to find quite a few more of these species here as well. And this is just a total of the mosquitoes that I've collected so far just in Portage County. These are urban, this is out of my backyard so, Ochlerotatus canadensis, that's a mosquito that has, you know, migrated down from Canada obviously.
And then Coquillettidia perturbans these are the cattail mosquitoes, so it's obvious they're going to find a lot of those in cattail marshes. We collected from Moses Creek in Schmeeckle Reserve and Plank Trail in Schmeeckle Reserve. These are a lot of woodland mosquitoes right here, which makes sense because the Plank Trail runs through wooded lot. And then some snow-melt mosquitoes.
We found one Ochlerotatus fitchii and one Ochlerotatus provocans. So those are two mosquitoes that are going to be some of our earliest emerging mosquitoes. So I wanted to give thanks to the College of Letters and Sciences for the opportunity to give this lecture. I really appreciate that.
It's quite an honor. And also to the Portage County Library for hosting this community lecture series. And to my student Ilana Fish, who's sitting over there, who actually came to me as a high school intern last winter, doing her J-Term internship. She was very interested in insects, and I lured her into my lab to identify mosquitoes as a freshman.
But she's doing it. She got down to 20 minutes on identifying a mosquito the other day. So I think that's pretty good. And then Dan Phillips, he's the student that you saw in the picture.
He identified a lot of mosquitoes for me. Maranda Cardiel and Cheryl Bartram. Maranda has done a lot of collection for me, especially the larval mosquitoes. Cheryl did some ID'ing for me this summer.
And Erica Swenson and Alecia Stewart-Malone. She is the one who put together, helped me find this eco-region map and work on collecting from there. And then the University Personnel Development Committee for the grant that provided money to collect these mosquitoes. And UW-SP College of Letters and Sciences for Undergraduate Education Initiative Grant also provided some money for funding some students for doing this research.
And that's my son, Wyatt, a couple of years ago, helping me collect mosquitoes. And that thing is full of mosquitoes and he's not afraid at all. So that's pretty cool. (audience applauding) Thank you.
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