Chapter 9 – Finding and Working with Insectsw3.marietta.edu/~biol/imaging/c9_insect_study.pdf1...

Chapter 9 – Finding and Working with Insects

McShaffrey Draft 1 Last printed 1/15/2007 2:54 PM

Chapter 9 – Finding and Working with Insects of 30

D. McShaffrey – Draft Document – All rights reserved. 2 Last printed 1/15/2007 2:54 PM

At this point you are probably more than ready to try your hand at insect photography. The next question is “where are the bugs?” Insects are probably the most numerous macroscopic organisms on earth. They outnumber us by a huge number; according to the Smithsonian there are probably a few quintillion around at any given time on the planet. Chances are, with a little looking you just might run into one! OK – you are not amused. You want to find interesting insects that are big enough to photograph, attractive, and which won’t sting or bite. Well, that’s what this chapter is about. Seriously, insects are everywhere, in just about every habitat. Despite that, it often seems that when one wants to find an insect that can be difficult to come by. In order to be a successful insect photographer you have to learn enough about them to be able to predict where and when the species you are looking for will be there.

Finding Insects In terms of habitat, knowing where to find an insect is largely a matter of knowing what it eats. It’s easy to find mosquitoes in the summer for instance; all you have to do is walk around, essentially using yourself as bait. Likewise, butterflies visit flowers to get the carbohydrates (from the nectar) that they need to power their flight muscles. Caterpillars – larval butterflies – will be found on the host plants upon which they feed. These are often very specific; everyone knows, for instance, that monarch butterfly caterpillars are found on milkweed plants and that tobacco hornworms (right) are found on – tomatoes (I’ve never grown tobacco, and the hornworms on my tomatoes are always predominately tobacco hornworms although the odd tomato hornworm does show up). In other words, for many insects all you have to do is go to the food source.

Entomological Light & Magic – Insect Photography in a Digital Age of 30


Another method of finding insects is going to areas where they congregate for reasons other than feeding. Recently the Asian Ladybird Beetle has made a name for itself by congregating in huge numbers on the sunlit sides of houses in the late fall. They are seeking to get under the clapboards (many succeed) and hibernate. If you want to photograph them, late fall on the side of a house is a good place to look. Then there is the tendency of dragonflies to gather near water, where the males wait for females to approach. Dragonflies lay their eggs in or near

water, so it’s a good place to mate and the concentrations of males near water make streams and ponds the places to go to photograph dragonflies. Of course, many insects live in very restricted habitats and going to those specific habitats is your only real chance of seeing them. Cave crickets (above) live in caves, aquatic insects in the water, and wood-boring beetle larvae in tree trunks or fallen trees. See the table below for specific places to look for insects of the different orders.

When & Where to Find Insects As you might have guessed, timing is everything. Here in Ohio, we have this thing called winter; it’s tougher, but not impossible, to find insects in Ohio in the winter. Many insects are strongly seasonal, and may be around (in the adult form, at least) for only a few days each year. The time of day is crucial as well. Many insects visit flowers by day, moths in general visit flowers at night. Both the season and the time of day can often be tied closely to the host plant’s life cycle. So, finding a particular species of insect requires either luck or a fair amount of study; but finding insects in general requires a little knowledge of insects in general, and that’s what we’ll talk about here (some more specific advice will be found in the following chapters which take up each group of insects in turn).



Where to find Insects

Order1 Adults Larvae Notes Ephemeroptera Mayfies

Attracted to lights near water, often in huge numbers.

In various aquatic habitats, particularly clean streams and rivers.

Adults of each species present for only a day or so.

Odonata Dragonflies and Damselflies

Usually found near breeding water (streams, rivers and ponds), particularly adult males.

In various aquatic habitats. Males patrolling territories near water are particularly easy to spot.

Orthoptera Grasshoppers, Crickets, Katydids

Found on food plants, which are varied from grasses to trees. Adult males often call.

Found in same habitats as adults, do not fly or call.

Generalist feeders, smaller larval stages often very difficult to find.

Phasmatodea Walkingsticks

Usually perched on food plants in forest.

Same as adults. Notoriously difficult to find. Often high in forest canopy.

Plecoptera Stoneflies

Usually found near water; some adults emerge onto snow!

In various aquatic habitats, particularly clean streams and rivers.

Rarely as numerous as mayflies.

1 There are about 26 Orders of insects (depending on which authority you believe); only the more common are listed here. The authority I’m consulting is Borror and DeLong’s Introduction to the Study of Insects by Charles Triplehorn and Norman Johnson (Brooks/Cole, 2005).




Order Adults Larvae Notes Isoptera Termites

Found in large nests either on the ground or in trees, also in rotting wood, such as that of your house.

Restricted to the nest. Look also for the covered walkways termites construct aboveground between their food and their nests.

Mantodea Mantids

Predators, found wherever abundant insect prey is found.

Same as adults, harder to spot.

I find mantids most reliably on the edges of fields and in gardens.

Blattodea Cockroaches

In leaf litter, human habitations. Primarily nocturnal.

Same as adults. If you don’t want to find cockroaches do not get up for a glass of water in the kitchen at 2AM and turn on the light.

Hemiptera True Bugs, Cicadas, Hoppers, Aphids, etc.

Bugs, hoppers, aphids, scales, etc. usually found feeding on host plants. Cicadas do not feed as adults and live in treetops.

Usually found with adults. Cicadas live underground feeding on plant roots.

A number of Hemiptera, both adults and larvae, are aquatic.

Coleoptera Beetles, Weevils

Everywhere. Often feed inside of food. Too large a group to characterize easily.

Neuroptera Dobsonflies, Lacewings, Ant Lions, Owlflies

Adults never numerous, lacewings found in association with aphids, others do not feed as adults and are best caught at light traps.

Lacewing larvae feed on aphids; dobsonfly larvae are aquatic, and ant lions form distinctive pits in sand protected from rain (under overhangs).

Except for clusters of ant lions, this group is hard to encounter in large numbers.




Order Adults Larvae Notes Hymenoptera Bees, Wasps, Ants

Look for adult bees and wasps at flowers; ants are widespread on the ground and on plants.

Usually found in the nest with the notable exception of sawfly larvae, which look like caterpillars and feed on plants.

Many species are parasitic on other insects and the best way to find them is to find the host insect.

Trichoptera Caddisflies

Adults emerge from water, often in large numbers like mayflies.

Aquatic, often with portable cases built with silk and objects gathered from the environment.

Adults and larvae found near (in) most aquatic habitats.

Lepidoptera Butterflies, Moths

Adults sip nectar and can thus be found at sugar sources. Moths are mostly nocturnal and can be captured by spreading a sweet substance (molasses) on a tree trunk. Also attracted to lights.

Usually associated with a food plant; often very specific host plant requirements. Egg laying adults will also come to the host plants.

Butterflies are diurnal and usually much more colorful than moths.

Diptera Flies

Everywhere. Feed in or on food source. Like beetles, flies are too large a group to characterize in a table.

As you can see from the table, some insects have habits which make them very easy to find, while others are more difficult. I can’t stress timing and habitat enough. Let me relate a story to illustrate this point:



In graduate school our lab technician and I made several trips to a particular stretch of river to retrieve a particular mayfly larva. The lab I worked in was one of the best in the world for studying mayflies, and we knew the habitat requirements precisely. At the site we used SCUBA gear to work the sand on the bottom of a deep, fast-flowing river to look for the mayfly larvae. We never found them, but that’s not the point of the story. One night we set up ultraviolet lights to attract adult mayflies and caddisflies as they emerged from the river. A large white sheet reflected the light and the insects came in swarms (it’s not unusual to fill up mason jars when collecting in this way). Periodically we’d here a large thump and crash of wings and we’d discover a female Dobsonfly 4 or 5 inches long that had been drawn in. Over the period of a couple of hours we collected over 50; it’s usually rare to get one. We were in the right place at the right time. A year later we were at the same site, again looking for the mayfly. It was about our 4th year at the site and over the time we had also become obsessed with catching a particular type of dragonfly which flew over the rapids and never came close enough to catch. We had tried all types of schemes to net these dragonflies without success. That morning I was walking on a sheet of bedrock at the water’s edge, drinking my morning orange juice, when I noticed a dragonfly crawling out from the edge of the vegetation surrounding the bedrock. Chilled overnight, the dragonfly was seeking the sun so it could warm up and fly away. I bent over and picked it up with my bare hands; I caught several more in the space of a few minutes. After that, they were warm enough to fly away and join the elusive dance over the rapid. So, to photograph insects you need to know them a bit. It means learning the local habitats, learning a little botany, keeping records, and keeping your eyes open. Let’s take these one at a time. While it’s always nice to go on vacation and photograph spectacular insects in a faraway setting, most of your bread-and-butter work will be done close to home. You need to go to local sites and go to them frequently. Frequent visits help in a number of ways. First, after a while you won’t pay attention to the scenery and can focus on the insects. Second, you will be there at different times of the year and thus will see different groups of insects as they enter their brief adult stages. Third, you will see what flowers bloom and where and when they do so, so you can go to a precise place at the right time to see the insects you want to see.


Yes, you have to know the plants, at least a little. Many insects, particularly caterpillars are associated with specific host plants. If you want to photograph a monarch caterpillar you need to be able to recognize milkweed (actually there are a host of photogenic insects that use milkweed as a food source). Likewise it’s a lot easier to find a catalpa tree and then look for catalpa worms on it then it is to examine every tree for catalpa worms. Buy a guidebook, look for nature walks sponsored by local groups, join a gardening club, maybe even continue your education with a botany class at a local college. Records are also important so that you can duplicate finds from year to year. I’m notoriously bad at this myself, but modern digital photography and computers have helped me out. Whenever you take a photo with a digital camera the time and date are recorded, so all you need to do is keep track of where you took the pictures. Most imaging software will allow you to add the location information to the image file itself (it’s hidden from view), so even years later if you want to relocate a population of insects all you need do is locate an image you took of them and examine the file data (called metadata) to get the location, date and time. I’d also recommend keeping a written record of what you see, including maps of the site, GPS coordinates, etc. I carry a small notebook with waterproof paper and a waterproof pen to record these notes in the field. Perhaps someday soon cameras will have GPS chips in them and make the record keeping even easier! The most important thing, however, is to keep your eyes open. Many of you may already be birdwatchers, and thus know many of the tricks. Walk slowly. Stop often; your eyes are drawn to movement and when you are walking everything is moving. When you are still, only the animals are moving. As you walk, examine each tree, branch, stem and leaf for anything out of the ordinary – maybe a change in texture or outline, a slight difference in color, or a blazing red beetle chomping on the leaf. Look at all levels – on the ground, in the air, on plants from roots to tips. Watching a patch of open sky may reveal flying insects; watch where they land and don’t move your eyes from that site. Practice bringing your camera up to your eye without losing sight of the insect you’ve spotted. Turn over (and then replace) logs, rocks, leaves and other objects. Look on the bottom and the tops of leave attached to plants. Listen for the sounds of insects jumping, flying, walking or even eating (A large number of caterpillars feeding in trees produce so many droppings – frass – that the sound of the frass falling through the leaves can sound like a gentle rain. Don’t look up). Listen for male insects calling.

If you don’t see insects directly, look for places where they congregate. Virtually any flower will attract insects; that’s kind of the whole point of having flowers, after all. Any type of edge habitat is usually productive, so look for insects at the edge of a forest, where a field meets a mowed lawn, at the edge of a stream or pond, even at the edge of a parking lot. If it is dry, look for insects near water. If it is raining hard, look for a sheltered place. Dawn and dusk are often productive as day-fliers will just be coming




out (or roosting) while the night-flyers are heading in the opposite direction (one very attractive Florida fly is only active for about an hour a day, at dawn). Dawn is also a good time for day fliers as they may be too cold to fly away at your approach.

This fly (Volucella barei, Family Syrphidae)

is active for only a short while in the morning.

Look around human structures. Insects perching on the side of a building are often much more apparent than when they perch on tree back or vegetation. Human activities often attract insects as well. They come to food that is left out, gardens, lawns, pets, compost piles, etc. They may lurk under stones on a walking path or used to edge a garden. Others are attracted to damp areas in basements – and many species find the glue used in book bindings quite attractive. Don’t overlook eves, attics, picnic shelters and outbuildings; often these provide shelter from the elements. Ant lions, for instance, are often found in sandy ground under the eves of houses; otherwise they are restricted to small patches at the bases of cliffs or in the shelter of particular plants.



Trapping Insects

If you can’t find insects you can often trap them as the average human is somewhat more intelligent than the average bug. Light traps are very productive for many species including mayflies and most aquatic insects as well as moths and beetles. Insects are attracted to light at night, and since they see at shorter wavelengths than we do, blue or ultraviolet lights work best (regular incandescent lights, as long as they are not the yellow “bug” lights work fine too). There are several ways to light trap. The simplest is to go where lights are on and look around; sometimes you can find insects attracted to an outside light as late as the next morning. Or, leave a light on all night at a window with a screen (the window need not be open) and you will be able to pick insects off the screen until dawn. In the field, buy one of the portable ultraviolet lights designed to allow pet owners to look for their pets’ “accidents” in the house and place the

light in front of a white sheet. You can pick the insects off the sheet or photograph them in place. Smear a bit of molasses on a tree trunk and check it periodically for moths at night. Dig a hole and place a plastic container in the hole so that its top is level with the ground. Place a cover of some sort that is bigger than the opening of the container over the container and prop the edges of the cover up slightly off the ground with pebbles or sticks. Insects walking on the ground will fall in and can be recovered later (a layer of soapy water in the container increases yield but the specimens, admittedly clean, are just a little too dead to photograph well). Commercial outfitters such as Bioquip can sell you Malaise and other traps; these tentlike mesh structures (above left) are set up along the flight line of insects and collect an amazing diversity. Like the pitfall traps, most have some sort of container to collect the insects, and again you don’t want to put a killing agent in it. Many entomologists have noted that insects, particularly flies, are attracted to yellow objects. Working my way through college I noticed that the yellow department of the department of transportation trucks we drove were particularly attractive to flies! Yellow margarine containers set out with antifreeze (monitor the traps to prevent pets or wildlife from drinking the antifreeze) work well, as does soapy water in the container, but again the specimens are not very photogenic after drowning. Still, yellow may help attract insects; a sheet of yellow plastic displayed near a garden, for instance. Another old trick is a Berlese funnel used to extract insects from soil and leaf litter. Get a large funnel, put a small piece of coarse screen inside it just above where the funnel narrows, and dump your leaf litter and soil on top of that. A small light bulb above the soil will warm and dry the soil, driving the insects down past the screen to tumble out at the bottom. Traditionally the entomologist would place a vial of alcohol there to capture and preserve the insect; you might want to use an empty 2 liter bottle to capture the insects alive (a bit of moist paper at the bottom of the bottle will enhance survival).



Some insects will never settle down and you’ll have to catch them. Good-quality insect nets can be purchased from companies like BioQuip, Carolina Biological, and Wards Biological, to name a few. Spot the insect and sweep it up, being sure to follow through and end the sweep with a quick flick of the wrist to fold the net over the rim and thus trap the insect. The insect can then be removed by catching it in a plastic jar pushed into the net. Other insects can be caught by hand.

Aquatic insects can be caught with dip nets of various sizes; in streams a kick screen works very well. When using a dip net, try to bring up a sizeable amount of bottom sediment and any plants growing in the water. Place this mass on shore and dig through it to find and remove the insects. Be sure to replace the material in the pond. Kick screens consist of a piece of screen (window screen is a good mesh size) stretched between two short poles. Ideally, one person holds the poles stretching the screen across a short area of the stream, with the water flowing into the screen. The poles should be tilted back so the top edge of the screen is just above the water’s surface. The other person kicks and otherwise disrupts the substrate (bottom) upstream, dislodging the insects and causing them to flow downstream into the net, which is then lifted quickly from the bottom.



Photographing Insects

Once you have an insect, you need to photograph it. If you found the insect in a natural setting, then you can photograph it in place. This means approaching the insect carefully, setting your camera, and taking the picture. This sounds simple, but in practice there is a lot more to it than simply walking up and taking a picture. Before approaching the insect, you need to have in your mind an idea of what the final picture will look like. Are you trying for a portrait of just the face of the insect? Perhaps you want a lateral (side) view. Maybe a dorsal view – looking down from above - will work best with this insect. Whatever your decision, it helps to have the final image in mind as you make your approach. It also helps at this stage to begin to get your camera setup to take the picture. If you will be making a macro shot then you will want to have your macro lens already on the camera. Likewise, you can make initial settings of the camera before

approaching the insect. For instance, if you want to maximize depth-of field then set the camera to shutter speed priority, set your camera to the slowest shutter speed you can use and let the camera automatically select the f-stop. Sometimes, if I want to maximize the size of the insect in the final frame, I will set the lens to manual focus and turn it to the closest possible setting. Then I move towards the insect, and when I’m close I make the final approach looking through the viewfinder, taking the picture when the focus is sharp. Making these settings before approaching the insect will minimize your chance of disturbing it. I’ve found it best to approach the insect viewing it through the camera if possible. In many cases, the insect does not perceive the camera to be as much of a threat as a human face. If the camera has a live LCD screen, then you don’t even have to have your face behind the camera. Many insects will tolerate a much closer approach when it is made by a disembodied camera. However you hold the camera, approach slowly, smoothly, and keep yourself as low as possible. In particular, try to keep your body below the local horizon – whether that be the bushes, trees or the actual ground horizon. Watch the insect carefully – if it makes any movements pause for a moment and let the insect settle down. While moving in, I often take one or two “insurance” shots just in case I spook the insect before I get into final position. Pay attention to the angle of the camera as you approach the insect – try to keep the camera parallel to the subject. For instance, if you are taking a lateral picture of an insect, the back of the camera should be parallel to the side of the insect. If you do this, it will help keep both the head and the tail of the insect and focus.



Chances are you will find that some insects are more cooperative than others. This difference can even occur among members of the same species, with some being more tolerant of a close approach. If you do frighten an insect, however, don’t lose sight of it. Watch where it lands and try approaching again. Some insects will fly readily on the first approaches, then settle down and allow you to photograph them. In an ideal setting, there will be a number of insects of any given species, so if you frighten one you can approach another. Also, if there are a number of insects of the same species around, before focusing on any one individual, look at all of them and try to pick out ones that are particularly attractive. As insects age their wings become tattered, they may lose appendages, and their colors may fade. If you are going to photograph an animal, it may as well be an attractive one; we use this principle when filming human models to sell clothes and other goods, if we didn’t I’d be making a lot more money as a model than as a college professor!



Posing Insects Some insects simply will not pose for you, or if they do, they pose in a place where it is either difficult to photograph them (because of angles & obstructions) or the setting isn’t ideal (the insect blends in, the setting is unattractive, the setting is too bright or dark, etc.). In these cases you may choose to intervene a bit. From my point of view, the simplest intervention is a little “gardening” – moving errant twigs, blades of grass, leaves, etc. so as to allow for a more pleasing composition. There is no problem doing this as long as you are careful not to damage the ecosystem unduly (such as tearing up an endangered plant to take a picture of a common grasshopper). Do this gently and slowly as there is a great chance of scaring the insect while you are manipulating its environment. In other situations, more than simple rearrangement of the environment is needed. The insect may be in a hiding place, it may blend into the environment a little too well, or it may be in a setting that is simply to difficult to work in or too unattractive to photograph. In these cases you may have to reposition the insect by catching it and physically moving it. This is easily done with many insects; caterpillars in general, for example. Simply pick the caterpillar up (see the section on Lepidoptera for some cautions as some caterpillars have poisonous hairs and you shouldn’t pick them up) and place it in a better place. If you are moving it from one plant, seek out a plant of the same species if possible as the host-plant relationships between particular caterpillars and particular plants are both exclusive and well-known. A monarch caterpillar perched on an oak leaf looks as out of place as a football player in a chorus line. Many non-flying insects can be repositioned in this way. With flying insects you might want to take a few insurance shots in the non-optimal setting, then purposely flush the insect and hope it alights in a better place nearby.

The leaf in this shot is being held by fingers just out of view to the left.

Many insects are far too flighty to be posed in the casual manner just described. It might be necessary to calm these insects down before photographing them. There are several ways to do this; perhaps the most often used is chilling. If you carry an icebox or cooler with you in the field you can place the insect there for several minutes to cool off (the larger the insect the longer it will take to cool). There are a number of 12-volt microfridges on the market for use in cars; these also make good chilling chambers. The chilled insect can then be removed and carefully posed. If you take this approach you need to have a good idea of what the insect looks like normally as it is easy to position an insect in an unnatural pose, perhaps with the legs at an angle that



they would not normally assume when alert. The insect may be sluggish and unwilling or unable to grip the substrate you are posing it on. In these cases a rougher substrate which will catch the claws of the insect may help; it is more difficult to pose an insect on a smooth leaf than it is on a rough piece of bark. You might also want to put gravity to work for you; an insect

that normally clings to the side of a tree with its head up will look normal if sprawled on a log laying sideways on the ground (provided you get close enough so that only the bark shows in the frame around the insect). In addition to chilling, other means of anesthetizing the insects can be used. Entomologists typically carry kill jars when collecting insects for museums; these kill jars use agents such as ethyl acetate to kill the insects. When the insect is placed in the jar for a shorter period of time, however, a kill jar becomes a stun jar, and the stunned insect can be posed. Likewise other agents including carbon dioxide can be used to stun insects temporarily, but I usually stick with chilling. There are also a few mechanical tricks that can be used. Dragonflies, for instance, can be stunned by dipping them into water and/or twisting their heads about 360 degrees. Lest you object, I must report that in the majority of times I’ve tried either of those techniques so little harm was done to the dragonflies that they zoomed off before I could get the photo I wanted. Butterflies and moths can be stunned by squeezing the thorax

between your fingers for at least 10 seconds. How hard to squeeze? Too little and the butterfly flies; too hard and …. Let’s just say it takes some practice, and is something you might want to try with common species, particularly ones which are pests in your garden. Anytime you work with a chilled or stunned insect a big part of the trick is to wait until the insect has almost completely recovered before photographing it. Until it is almost ready to fly it simply won’t look right to the critical observer. Perhaps the head will be held at a funny angle or maybe the legs will look awkward. As the insect regains its wits it will bring its various appendages into a “natural” pose and you will then need to work quickly. Many chilled insects will shiver their wing muscles to warm up; a good time to photograph these insects is between the bursts of shivering.



One step beyond posing insects in the wild is to bring them into a studio. I photograph a lot of dragonflies and my office/lab has a number of props to help convert it into a studio when I return from the field with a bunch of dragonflies. First, after netting them in the field, I transfer the dragonflies to glassine envelopes for the trip back. On arriving back at the lab, I place the envelopes in the fridge while I set up my tripod and props. For species that perch on vegetation, I have a selection of twigs which I can clamp in a small vice on the tabletop. I then take the dragonflies, starting with the smallest (they chill fastest) and perch them on the stick. I position the stick so that the rather featureless brownish-gray concrete floor is well in the background; these photos look as if the dragonfly is perched over somewhat muddy water. Alternately, I also keep some green and blue towels handy; blurred in the background these suggest water, vegetation or sky. I have a number of clamps and duct tape handy to hold the towels in position on tabletops, filing cabinets, doors, chair backs or wherever I need them to provide a “natural” backdrop.

For species that perch on the ground I have several large, attractive river rocks of various colors and textures stowed under a chair in a corner of the lab. I pull these out; splash a bit of water on them, and frame tightly so that the rock is the only background visible in the frame. If a situation really demands some actual greenery (as opposed to a blurred green towel in the background), I may take them to the greenhouse and pose them there.

Which dragonfly is perched on a rock in the studio, and which is posed outside under natural light? Is it the Blue Corporal (left) or the young Common Whitetail male (right)?

Dragonfly Perched in Studio

The background is a concrete floor.



If you need to pose an insect, you also have an ethical obligation to acknowledge the fact that the photo was posed. To do otherwise is misleading and it can have some unintended consequences. On the Dragonfly Listserve there was once a discussion about how dragonflies perch. It was suggested that we all examine our photographs to see which legs were involved (many species only use the back 4 legs to perch, and the distribution of this behavior among the various groups of dragonflies was the topic of discussion). It turned out that many of the photos on the web were useless for analyzing this behavior as it wasn’t known if they were posed or not; posed dragonflies do not necessarily use their legs in the same way “free” dragonflies do. If I photograph posed insects I add the keyword “posed” to the metadata and try to include it on the caption accompanying the photo. Likewise, if I take the picture inside in the studio, I add both “posed” and “studio” to the keyword metadata. Especially in a digital age, we photographers must be in the vanguard of protecting the “truthfulness” of our images, and the best start is to acknowledge any deviations from the natural condition. Labeling posed and studio shots as such also makes photos taken under difficult and natural conditions much more meaningful, and properly adds to the acclaim of the photographers who took these more difficult shots.



Safety when Working with Insects

If you bought this book you probably are not particularly scared of insects. Still, the idea of handling a bee or wasp may give you pause, and with good reason. Many insects have a variety of defenses and some of these can be quite effective, even against humans. More people are killed by bees (and other stinging insects) than are killed by just about any other animal in North America, except deer (who have been waging a suicidal war against cars since the invention of the car and taking out a few of us in the process). Unfortunately, it seems that the more spectacular an insect is from a photographic viewpoint, the more likely it is to be dangerous in some way. Fortunately, most of these defenses are pretty harmless to humans, especially those who take a little care. Let’s take a look at insect defenses.

Many insects are poisonous, and usually they warn us of this with bright coloration. Before we pick up on this, however, a few words about the word “poison” are in order. I had a friend who was a high-school teacher in Iraq. A good botanist, he was visiting the US and taking some graduate classes (this was long before the US went into Iraq). On a field trip I noticed a lot of poison ivy along the trail, and I was worried that Hussein (yes, that was his name) might not be aware of it. So, the helpful American, I pointed it out to him. “Hussein – this is poison ivy”. Since he was a botanist, I didn’t bother to explain how to identify it – he could handle that on his own. Sure enough, when we came to a clearing, I turned around to see Hussein, with a cornucopia of poison ivy gathered up in his arms. He looked up at me over his magnifying glass and asked, innocently, “Why do you call it POISON ivy”? Well, to make a long story short, he didn’t get it – the rash, that is. His English was pretty good, and he knew what “poison” meant, and had been careful not to eat the stuff. Poison is a pretty complicated word, as it turns out, and understanding the various forms of poison is helpful in learning how insects protect themselves and how we can protect ourselves from them. Loosely speaking, a poison is any chemical which disrupts our normal metabolism. Usually poison does its work after being ingested, but it can be introduced into our bodies in a number of different ways – through the air, across the skin, even injected below the skin. Insects use all these methods as a means of defense.



Remember that insects are small – the average insect (for that matter the average animal) is the size of an ant. A small ant, at that (the huge number of insect species skews the size distribution, so even when you toss in vertebrates including things like the blue whale, the average size of animals is mostly determined by the many species of tiny insects). Being small, there are a lot of things that want to eat them, and they need a defense against that. Many carry poisons in their bodies. Often these poisons, in addition to disrupting metabolism, taste and/or smell bad; thus potential predators tend to either avoid the insect carrying them, or spit them out right away. The insect may not want to wait until it is crushed in the jaws of a predator to let the predator know it is distasteful, so many insects will secrete or even eject the chemicals from their bodies before the predator has too good of a grip. Many insects warn the predators of their defenses by having bright body colorations; after one or two bad encounters even the most stupid predators learn to avoid brightly colored insects in general, even those harmless ones which mimic the more distasteful ones. Where do the poisons come from? A surprising number come from the

chemical defenses of the plants that the insects feed on. North Americans are most familiar with the example of the milkweed plant, which has a number of poisonous chemicals in its tissues, and, for backup, a milky sap that literally gums up the mouthparts of insects not deterred by the other chemicals (natural rubber is a similar defense used by the rubber tree). Several insects, most notably the Monarch Butterfly (in its caterpillar stage) are able to defeat these chemical defenses, and actually incorporate the defensive chemicals into their own bodies (see picture above).

The poisons in this Monarch caterpillar’s body are no defense against this Fishing Spider – which subdues the caterpillar with poison of its own, injected by its fangs.



One of the most interesting stories concerning chemical defenses and bright warning color is often told incorrectly. Every schoolchild knows that the bright red Monarch Butterfly is poisonous, and its look-alike, the Viceroy, is not. This is the classic example of a phenomenon known as Batesian Mimicry, whereby one toxic or dangerous animal (the model, here the Monarch) is imitated by a non-poisonous animal (the mimic, here played by the Viceroy). Scientists knew the Monarch was unpalatable because when they fed a Monarch to a tame Blue-Jay it immediately regurgitated it, and afterwards refused to eat either Monarchs or their mimics the Viceroys. Another Blue-Jay would eat Viceroys all day long until the experimenters slipped in a Monarch; after that the Blue-Jay would refuse both. The only problem with this experiment lies in the details. The Monarchs were fed on milkweeds since, as every schoolchild knows, that’s what Monarch caterpillars eat. Every schoolchild does not know what a Viceroy eats, so they fed them caterpillar chow (yes, there is such a thing). The caterpillar chow is a generic formula that many caterpillars can develop on, but it does not have any unpalatable chemicals in it, so adults reared from caterpillars fed such a diet – even Monarchs – are perfectly edible, at least to a Blue-Jay’s palate. Since that early experiment, it has been discovered that many, but not all, Viceroys feed on plants which also have defensive chemicals, and Viceroys reared on those plants are unpalatable (again, determined via the Blue-Jay test). This means that in nature the Viceroy and Monarch are both likely to be unpalatable and thus their relationship is one of Müllerian mimicry, where two toxic or dangerous animals look alike to help reduce the “training costs” associated with getting the predators acquainted with what can and can’t be eaten. A regurgitated butterfly is still a dead butterfly, and if its death prevents the death of others of its species and similar-looking species then it is a good deal for all the animals who look alike since they are less likely to get eaten. The more similar looking individuals from each species are to the overall “model” the more likely they are to live and produce more look-alike offspring. Müllerian mimicry is widespread; the common yellow-and-black of stinging insects is just one example (there are also some harmless species that are Batesian mimics of this Müllerian mimicry complex). Incidentally, bright colors are there to warn birds, amphibians and reptiles away; most mammals do not see color well, humans being an obvious exception. Contrasting dark and light areas work well to warm mammalian predators, and if the light area is a bright color it will warn off the birds, amphibians and reptiles as well. So what does this have to do with insect photography? Well, the more obvious an insect is the more likely it is to be poisonous, or to sting, or smell bad. Of course, those are the insects you most want to photograph! This means that you have to be a bit more cautious when working with these insects, and with a little knowledge you will be able to photograph them in complete safety (from the insects at least – knowledge of the insects won’t protect you from the crocodile sneaking up behind you as you focus on a streamside dragonfly in Africa).



Let’s look at the various insect defenses one-by-one: Biting: Most insects can bite, and the larger ones may be able to inflict a painful bite. Notorious biters include ticks, horse and deer flies, blackflies, mosquitoes, larger beetles, dragonflies, dobsonfly larvae (hellgrammites), ants, giant water bugs, backswimmers, coreid bugs, assassin bugs, Mike Tyson, bed bugs, and fleas (the list is by no means inclusive). Of these, only the ticks, flies, mosquitoes, bed bugs and the fleas are likely to seek you out and bite you. A good insect repellent, long pants, a long-sleeved shirt and a hat (all of light color, but avoid floral prints) and your pants tucked into your socks will protect you from the insects who want to attack you. Biting insects also tend to avoid sunny, breezy areas where they dry out quickly, so avoid shady, humid areas if possible. Most of them prefer to attack large mammals, which are dark in color, so that’s where the light clothes comes in useful (horseflies are particularly attracted to my dark green station wagon). As for the other biters your best bet is to avoid handling them, or handle them with care. Grab the body where the head cannot swing around to bite. Use forceps (tweezers); at least one company (Bioquip) markets forceps made of thin metal (larval forceps) that can be used to grab most insects without damaging them. I should also note that all spiders and centipedes have a poisonous bite. The bite of the Black Widow and the Brown Recluse are well-known for their serious effects, sometimes including death, and larger centipedes can also be dangerous. These organisms, as well as some of the insects, inject a cocktail of compounds as they bite. Some are outright poisons, whereas others, not toxic in their own right, may trigger an

allergic reaction. A severe allergic reaction (anaphylactic shock) can lead to death in individuals already sensitized and reactive to the injected allergen. I generally avoid handling spiders and centipedes with my hands, preferring to use forceps (which I always carry with me). Spiders can also be manipulated with small sticks; if you pick a spider up with a stick it will probably attach an anchor line of silk and jump off; you can place the hanging spider where you please (note to children and adolescents of all ages: “where you please” does not mean anywhere on the person or clothing of an avowed arachnophobe). Even if no poison is injected, disease organisms (such as those that cause sleeping sickness, Lyme disease, West Nile Fever, etc.) may be injected; it’s best to avoid insect bites when you can.



Pinching: Many insects have either small claws, or more commonly, larger spines which can be manipulated to pinch your skin, sometimes painfully. Of course, non-insects like crabs, lobsters and scorpions all have large claws that can inflict a painful pinch. No one ever dies from this. Careful handling will usually avoid any problems; most of us know, for instance, that a crayfish can be picked up by grasping it behind the legs with the pincers. In other cases forceps or a net may be useful. Secretions: Many insects – a surprising number, in fact – secrete some sort of chemical when handled. The volume and force which with the chemical is excreted varies widely. Grasshoppers, for instance, offer up an unappetizing “tobacco juice” (actually regurgitated stomach contents with a few other goodies) at their mouthparts when you pick them up, and they will rub it on your skin if you let them. Stink bugs got their name from the smelly chemicals exuded from small pores on the body and at the leg joints; sometimes you can see the small droplets). The Bombardier Beetle doesn’t mess around; it uses a two-chambered apparatus at the tip of its abdomen to explode a mist of hot – boiling hot – noxious chemicals at its foes. The explosion is audible and the spray can be directed with precision – say at an ant attacking a particular leg, or a scientist tugging on another (with forceps, of course). Most of these chemicals are harmless, at least to the thick skin of your fingers, although they may be irritating if you later wipe your eyes or nose. If in doubt about an insect or its secretions, handle it with forceps which will keep you out of the line of fire (as long as you don’t bring the insect to close to your exposed skin). These things aren’t usually a problem if you are photographing the insects without handling them. If you do get some secretions on your skin, wash it off with soap and water or some other cleanser; if nothing is handy spit on it and wipe it off on your socks (which should be outside your pants cuffs (see above)!


Urticating Hairs: This is a defense most often used by caterpillars, although some other organisms, such as tarantulas, may use it as well. Urticating hairs are fine hairs that break off the insect’s body easily, and impale themselves in the skin of the attacker in much the same manner as a porcupine’s much larger quills. Often they are coated with irritating or downright poisonous chemicals as well. Like the porcupine, the caterpillar cannot throw the spines (apparently spiders can, however), so if you don’t touch the caterpillar you are safe. Most of us run into the spines indirectly – walking into a caterpillar lowering itself from the trees via a strand of silk or brushing off one that has fallen onto our clothing. In most cases, on the skin of the hand, for instance, the sensation is a stinging not unlike what you get from handling fiberglass or a stinging nettle. A rash may develop. The real danger is that you might wipe some other, more sensitive body part, such as the eyes. In those cases, medical care may be needed. A piece of duct or other tape might be useful in removing hairs left on the skin after rinsing with water.

Stinging: This is the big gun of defense. In terms of terrestrial organisms, we are really talking about 2 groups – scorpions and Hymenoptera. There are a few other oddball groups that sting, but none are really of any consequence to us here. For the scorpions, the sting is definitely a weapon, used for both defense and offense. Any prey held by the front claws is in the exact position for the stinger to come over the back and jab. I have had limited experience with scorpions and my advice would be to always handle them with forceps or some other gripping device. Many are quite reluctant to sting, and some captive specimens are tame enough to hold, but it’s not something you want to take a chance with. The sting of most is probably similar to the sting of a yellowjacket, but a few are known to be deadly.



Stinging in the insects is really restricted to the Hymenoptera, although many insects, when caught, will make a pretty convincing display of trying to sting you. This is probably a case of behavioral mimicry, with a defenseless fly buzzing like a bee for all its might and jabbing the blunt, soft end of its abdomen towards your skin in the hope you will panic and release it. Apparently, it works often enough to reward the mimics. Dragonflies are sometimes said to sting, but this is not the case. There are some female dragonflies that lay eggs in plants, and they have a sharp ovipositor at the tip of the abdomen for this purpose. At least one dragonfly worker has reported having a female try to oviposit in his arm, inflicting a little pain in the process, but this was an extraordinary event, marveled at by others who have spent thousands of hours

handling dragonflies without incident. Likewise, there are a number of other insects, particularly grasshoppers, crickets, katydids and their kin with sharp ovipositors that could jab the skin if carelessly handled, but again this is very rare, and in these cases if a jab did occur, no venom is injected. Many of the Hymenoptera do sting. Parasitic Hymenoptera use a sharp ovipositor to inject their eggs into the bodies of their prey. They usually also inject a poison to incapacitate and paralyze the prey. Interestingly, in some species the female also injects a virus that incapacitates the immune system of the host, thus preventing it from attacking the egg or developing wasp larva. Most of these parasitic hymenoptera are tiny and their ovipositors wouldn’t penetrate your skin. Even the larger ones are solitary and their venom is optimized for invertebrates, not a big strong vertebrate like yourself, and thus they are of little concern although you might experience a little pinch and perhaps even some itching, as you would after a mosquito bite. That is, if they stung you at all, something that is highly unlikely unless you are handling them or they get crushed in your clothes.

The larger Hymenoptera fall into 3 major groups insofar as their stinging capability is concerned. Solitary parasitic wasps, such as some of the larger ichneumonids or things like the spider wasps and cicada killers are capable of inflicting a nasty sting, although it is highly unlikely and if it did occur it would only be one sting (the wasps being solitary, after all). Some of the larger ichnuemonids have an ovipositor capable of going through several inches of wood, but it is threadlike and not likely to be employed by mistake (these insects “listen” with their feet for the sounds of feeding beetle grubs down in the wood, so unless your skin is as rough as dry bark and you have beetles in your bones, you are probably safe). Likewise, the larger solitary wasps like the spider wasps and the cicada killer are unlikely to strike except as a last resort. Thus, unless you are handling them, you are unlikely to be stung. Once again, the venom is not optimized for vertebrates, but because of their large size the sting will probably still be painful (I’ve never been stung by one) and the larger amounts of venom are more likely to cause discomfort and/or an allergic reaction. Thus, to safely photograph these, simply avoid handling them with bare hands.




The second group of stinging Hymenoptera are the ants. If you get too close to an ant nest, you are likely to encounter the workers, which will defend the nest by biting you, and once they have a good grip with their mouths, they will use the leverage to drive their stinger in. Since the workers are all sterile females they all have ovipositors; being sterile they can devote the space inside their bodies that the queen uses for eggs to things like poison sacs. Many ants can also spray formic acid as an additional irritant. The sting of some ants is quite painful. Bullet ants of Central America (pictured) have a sting that has been likened to being shot, begging the question of how many people have both been shot and stung by these ants so as to be in a position to make the comparison! Other ants may have a much less painful sting, but because there may be millions of ants in a nest the combined effects of thousands of stings add up to quite a painful experience. Horror movies to the contrary, people do not get overrun by army ants and killed an eaten, although it might not be a good idea to be a drunk passed out near a nest. When photographing ants, try to determine where the nest is. Avoid disturbing it and concentrate on individual ants far from the main crowd; glance periodically at your shoes to make sure the ants haven’t formed a

boarding party. You do have your pants tucked into your socks, don’t you – you wouldn’t want ants running up your legs inside your pants, would you? The third and most dangerous of the stinging Hymenoptera are the social bees and wasps. This includes honeybees, yellowjackets, paper wasps, and hornets. Like the ants, most of the female workers are sterile and thus are not laying eggs. Since they are not laying eggs, they are free to give up their lives in defense of the nest (which is comprised of their genetic relatives, so their sacrifice still helps their genes survive). It is well-known that when a honeybee stings her barbed stinger stays in the skin. It rips out of the back of the abdomen, fatally wounding the honeybee, but leaving the stinger in the skin with its attached poison sacs still pumping venom through the stinger to the interior of the skin. You might think you are better off being stung by, say, yellowjackets, which do not leave their stingers embedded, but remember that the other wasps are free to sting and sting again. Unlike the parasitic wasps, the sting of the social wasps IS specialized to cause pain to vertebrates. The pain is instant and sharp, and remains for some time. In a person sensitized to bee venom an allergic reaction can take place causing extensive swelling; in severe cases this can lead to anaphylactic shock, a system-wide effect that can lead to death. Sensitized individuals



know to carry a pen of epinephrine with them to help counter the shock. Interestingly, although a high percentage of people claim to be allergic to bee stings only a small (1-2%) of the population will actually have a life-threatening reaction to bee stings.

To avoid the stings you need to understand a little basic biology. Bees and wasps largely act on chemical cues (it’s dark in that hive, so vision is out). They may find you largely by sight, but the decision to sting is chemically mediated. Each bee or wasp has small glands on its body that contain chemicals, known as pheromones, which signal others in the area to gather and attack. In the absence of the chemical, no attack will take place. The chemical will be released when an animal (you) gets too close to the nest or when the bee or wasp is handled roughly. Once released the chemical helps attract others to defense of the nest and causes them to sting. To avoid being stung, you want that chemical to stay put, and you do that by STAYING AWAY FROM THE NEST. Short of crushing them, you can do whatever you want to bees and wasps foraging on flowers. I routinely brush them away from a flower with other insects I want to photograph, or shoo them away from my barbeque – I just make sure not to crush them in any way, and I STAY AWAY FROM THE NEST. Even

if a bee gets caught in your clothes and stings you (I was stung once while waterskiing in the middle of a large lake), if you are AWAY FROM THE NEST you will only get one sting. If you are near the nest you could get yourself killed. Really. While photographing, keep an eye open for hives (yellowjackets, which often nest underground, have particularly difficult nests to spot), and STAY AWAY FROM THE NEST. To photograph the nest (such as the aerial nests of wasps and hornets), use the longest lens you have, set it up on a tripod, wear light-colored clothing, and, all together now, STAY AWAY FROM THE NEST.


The Entomological Life As you begin to photograph more and more insects, you will begin to develop an appreciation for them, and hopefully an increased curiosity. The simple need to identify the specimens you photograph will send you in search of more information. You will look for information on the web. You’ll consult books and discover dichotomous keys (left), which take you systematically through identification by focusing on one character at a time and making a decision as to whether your specimen is closer to one or the other of the two options presented. There are a lot of good books out there – not to mention all of the resources on the web. In the detailed chapter on each group of insects I’ll mention some of the more useful books for that group.


You will seek out people who share your interests. One good place to start is at a Natural History Museum; hopefully they have at least one person on staff who is good with insects in general. Such curators may often have a specialty, an group of insects on which they are world-class experts. If so, you might have a chance to get involved in some exciting research. Museums and nature centers also will frequently sponsor field trips, workshops and lectures on insects, and this gives you an opportunity not only to learn, but to meet like-minded people.



When it comes to insect photography, you’d be surprised how many people are out there doing it! You might run into them at a camera store or a photography club – both are great places to increase your knowledge of photography. You might also meet them out in the woods and streams, on some of those outings sponsored by various groups. Most of the people I meet in the field are pleasant and ready to share their tips and tricks – as well as commiserate with you over the difficulty of photographing certain elusive insects.

There are other places to go for support and help. Since much of my professional work is with dragonflies, I joined the Dragonfly Society of the Americas. It turns out that the organization is “overrun” these days by photographers; both professional entomologists and enthusiastic amateurs with a real interest in photography. The field trips at the annual meeting have an even distribution of folks with nets and cameras, and the photographic

chit-chat flows whenever people sit down – or even when they are standing next to each other around a pond waiting for the next dragonfly to perch (one nice thing about photographing insects is that most don’t respond to human voices, so you can talk all you want without disturbing them).



Another possibility to further your education is to take a formal class. If you are in college, it’s no big deal to take a course outside your major (if you are not already majoring in biology or entomology). I’ve found that interest and enthusiasm often counter experience and background; often the best students in my zoology class are not biology majors. If you are no longer in college perhaps your local college has some sort of “town and gown” arrangement to allow you to take a course or two without formally enrolling. In some cases, colleges offer field trips outside of the academic

year. These classes are often much shorter in duration, but intense in terms of the learning that goes on, and often the opportunities for photography abound. For instance, one of my students was bitten by the photography “bug” on a trip to Costa Rica and completed a degree in Biological Photojournalism (that’s him taking a picture of Harvester Ants in Costa Rica).

If you do decide to take a formal course, meet with the instructor in advance. Explain any concerns you might have about the academic work, and assure the instructor of your sincerity in taking the course (and then follow through!). Remember that the core of the course may not be photography, so don’t distract or delay the class taking pictures while the instructor is trying to do something else. Perhaps you can contribute in some way with your photography; several of my students take both Scientific Imaging and a Botany course in the same semester and use their cameras to photograph the specimens they will be required to learn. They then share these images with the other students as they study. Another place to meet experts and to give something back at the same time is with any of the many conservation groups out there. These groups, including The Nature

Conservancy, the Sierra Club, and the many local groups are always in need of volunteers for various projects, and these projects often involve training –



conducted by experts. Once trained you can give back by using some of that expertise on their projects. Many such groups also sponsor field trips, and often these trips are to ecologically sensitive areas normally of limits to the general public. I mentioned “giving back” and I can’t stress that enough. As your skills increase your expertise becomes a valued commodity that can be shared with others just starting out. Your photographs may have value to a number of organizations that need to document their work or promote it. And there are a host of other organizations – schools, summer camps, nature centers, museums, zoos, nature preserves, etc. – that will benefit from having you volunteer. Remember always that any hobby or interest can be much more than that. It can be a source of recreation and renewal, a source of fellowship and support, an outlet for your creative side, and a base for the lifelong learning that keeps us all vibrant. Have Fun!

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Data\Microsoft\Templates\Normal.dot Title: Entomological Light and Magic: Insect Photography in a Digital

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Chapter 9 – Finding and Working with Insectsw3.marietta.edu/~biol/imaging/c9_insect_study.pdf1...

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