This post was written as a guest blog for Explore the Outdoors, a program started by the Ohio Department of Natural Resources that endeavors to educate people about the natural wonders of Ohio. I highly recommend that you check out their website--it has great information on outdoor activities and state parks and reserves you can visit in Ohio. You can see my original post here.
Winter can be a beautiful time of year (when the weather
deigns to give us snow), but if you're like me, it can also be pretty dreary
for one important reason: there aren't many insects about. Sure, you might get
lucky and find some stink bugs crawling around inside your house or come across
a camel cricket or spider (not actually an insect, but an arachnid, of course)
in your basement, but the assorted stragglers can't quite satiate the need to
see our many-legged friends like the other seasons can.
If you haven't noticed yet, this post is going to emphasize
how amazing the insects and other terrestrial arthropods are. First, let's
establish some background. If you aren't already a fan of insects and would
rather step on them than appreciate them, ponder this: out of all living
organisms on the planet, over half are
insects. Furthermore, out of all the animals, almost 75% are insects. When you include the other arthropods, it
increases to 86%. Keep in mind that these are only species we have described so
far: estimates predict that over 90% of all animals are insects. The sheer
amount of diversity among the insects shows us that this is one important group.
Keeping that in mind, let's explore the diversity of insects in Ohio.
Nature, and in turn, insects, are not things you have to
drive to the outskirts of civilization to experience. It is (obviously)
literally all around us, and this is especially true with regards to the
insects. When I first learned of the total insect diversity, I was a bit
skeptical. After all, I hadn't really noticed too much variability in the
insects, other than mosquitoes could suck my blood, bees could sting me, and
scarab beetles had a penchant for flying into porch lights during the summer.
It wasn't until a few summers ago that I truly started looking for insects and
observing the mind-blowing amount of variability there actually was. I started
a personal project documenting the terrestrial arthropod diversity in my own
backyard (I didn't want to make the spiders and millipedes feel left out) and
have kept at it for three summers. I went through my yard a few times a week,
taking an hour-long walk examining the trees, shrubs, and other vegetation
during the day and night, just taking pictures and finding what I could. My
current tally surprised me: to date, I have found over 100 different species.
The kicker? All of these insects, spiders, and millipedes
have been found in an area only one acre in size. Now that's impressive! The
phrase "backyard biology" has never been more relevant! But that's
enough talk, it's time to look at some of the beautiful and interesting insects
that Ohio has to offer.
First up is an ant.
...that it's not an ant at all! This is actually a jumping
spider in the family Salticidae that mimics an ant, Synemosyna
formica. I start off with this spider to illustrate two points. Firstly,
that Ohio has some interesting and surprising diversity. Secondly, that it is
important to pay attention. You'll find that these little critters can be
surprisingly crafty, in a variety of ways. For example, a spider only has two
body segments: the cephalothorax (head) and abdomen. In this species, its body
is constricted to make it appear to have three body segments like an ant. In
addition, it holds its front legs in front of its body, mimicking the antennae
of an ant. You can see how small the spider is from the first picture: at most,
these spiders will grow to just under six millimeters long. When I found this
spider in my backyard, I thought it was an ant. That is, until it declined to
run away like the other ants in the area. Instead, it stayed on the underside
of the leaf I found it on, unmoving. This isn't ant-like behavior, so I caught
it on the hunch that it might be something different.
Next up is an insect that a
friend described as looking like "a Balrog that got hit with a
sneeze of tie-dye." It may look ferocious, but it's actually harmless to
humans. Other insects....well, not so much.
This is likely the biggest wasp you're going to find in
Ohio: the giant ichneumon wasp, Megarhyssa
macrurus. In this photo, it's inserting its three inch long ovipositor into
the dead wood of a tree, in search of one thing: the larva of another wasp, the
pigeon tremex horntail (Tremex columba).
It can detect the wasp larva's movements in the wood, locate it, and then lay
an egg next to the larva. Once the ichneumon wasp has done this, it will then
sting the horntail larva, paralyzing it. Later, the ichneumon wasp larva will
hatch and devour the horntail wasp, and continue to grow to adulthood.
With a lifestyle like that, it's a good thing this wasp is
harmless to humans! It's difficult to convey in a picture just how beautiful
this wasp truly is: the mixture of amber and yellow blend together to create
one of the most jaw-dropping insects around. If you're walking in the woods and
come upon some dead trees in a sunny area, search around a bit and you might be
lucky enough to find one.
This next insect is a personal favorite of mine. It's a
member of a fascinating family of bugs called the assassin bugs, a predaceous
family that preys upon other insects. They are generally considered beneficial
insects and are currently being studied for use in biological control regimes.
Something called an assassin bug probably isn't going to be too peaceful,
obviously, and these insects earn their name. They're ambush predators, and
once some prey comes into their hunting ground, they creep up behind the prey
and strike. They have a mouth like a straw, which they plunge into the
unsuspecting victim, pumping it full of digestive fluids to paralyze and
liquefy the insides of the unfortunate insect before sucking it out. Not
exactly the most polite thing to do, but it's a way to make a living.
In Ohio, we're lucky enough to have the largest terrestrial
true bug on the entire continent in our backyards: the wheel bug, Arilus cristatus. The picture above
shows its namesake: a structure on the top of the thorax that looks like a
cogwheel. This particular wheel bug has just emerged from its final instar (the
fancy word for a juvenile stage in the life of an insect), hence the pretty
salmon color. After a few hours, the color fades into a grayish black that
camouflages the wheel bug against trees. The wheel bug can grow a little larger
than two inches, making it a formidable predator. Its size allows it to take on
large prey and equips it with the weapon to do so: its beak is longer than its
head. This can be intimidating to humans, and the gut reaction of many people
is to either run from it or squash it. This fear is not well-founded. While the
wheel bug can indeed inflict a painful bite (being bitten by an assassin bug
isn't even an entomologist's idea of fun), it will only bite when provoked. Even
then, it might not bite. I've handled many wheel bugs and have yet to be
bitten: the key is to respect it and handle it with caution. I wouldn't
recommend handling a wheel bug, but it makes an interesting insect to keep in
an enclosure (it's in a butterfly cage in the picture) and observe its habits.
It's best to only do this temporarily and then release it to go on about its
business, but it's a valuable learning experience.
No mention of Ohio's insect diversity would be complete
without what many would argue to be the most beautiful moth in our area, the
Luna Moth (Actias luna). I had a
massive stroke of luck in my adventures this summer, with regards to this moth.
I was researching assassin bug diversity at Marietta College's Barbara A.
Beiser Field Station in early summer when I heard a strange sound coming from
some grass. I bent down and searched for the source of the noise when something
came crashing through the undergrowth.
A newly-emerged Luna moth was crawling towards me. There was
no question that it had just emerged: its wings weren't yet pumped up, so it
was in search of a tree to crawl up where it could safely expand its wings.
Seizing the opportunity (as well as the moth), I placed it on a nearby maple
tree and observed it for the next three hours. It takes a while for the moth to
complete this task, and moths are at their most vulnerable at this stage: they
can't fly away, and are nice protein-rich meals for any other animals that
might happen upon them.
You can tell that this individual is a male, due to the
thick antennae, which he uses to detect pheromones from the female: chemicals
that let the male know where the female is located and if she is ready to mate.
Adult Luna moths don't feed, focusing solely on mating to usher in the next
generation. In fact, adults don't even have functioning mouthparts. Due to
this, they only live for about a week, so mating is the top priority in such a
short time.
The Luna moth is in the moth family Saturniidae, a group
that includes the biggest moths in the world. The Luna moth is no exception,
with a wing span reaching up to 4.5 inches. The wing span of the Cecropia moth,
North America's largest native moth, is over 6 inches. Once you've seen these
moths, you're not likely to forget them. They're attracted to lights, and are
more abundant near forests, so start your searches there!
This is just a small sample of Ohio's insects: some are even
more colorful and have novel life histories. I haven't even mentioned the
beetles, which are the most diverse group of insects. In fact, one out of every
four living things on Earth is a beetle. Isn't that marvelous?
In a few months, winter will be over and the insects will once
again grace us with their presence. I encourage you to go outside and look
around your own backyard to see what you can find. If you want to go further
and identify what you've found, BugGuide is
the best resource for North American insects on the web. If you want to go
further than that, Nature 2.0 websites like Project Noah allow you to upload
photographs of the organisms you find, and are great for keeping a record of
what you've found.
What should you do if you want to find insects now? Well, the winter stoneflies should be coming out pretty soon...
What should you do if you want to find insects now? Well, the winter stoneflies should be coming out pretty soon...