This post was written as a guest post for Myrmecos.net, but I though I would post it here as well.
Flipping through the glossy pages of a Bioquip catalogue, you would think that entomology is a rather expensive pursuit. But, it doesn’t have to be. As an amateur entomologist, I’ve never had money to blow on equipment. Therefore, the majority of my collecting arsenal is home made from commonly available materials. I thought that I would share some of my creations here in the hope that will help others plunge into this exciting hobby without breaking the bank.
Let’s start with collecting equipment. When gathering small insects, such as ants, it is all to easy to accidentally squish your prize. That’s where an aspirator comes in. Though this is not a particularly expensive tool to buy, it is possible to make your own.
As you can see, the mechanism is quite simple. Two pieces of clear vinyl tubing are stuck through holes in the lid of a small jar or vial, and one is covered with a thin piece of cotton to prevent you from inhaling the insects you’re collecting. I used a small piece of cotton from a makeup remover pad, but something thinner would be easier to suck through. For example, fine wire screen or a square from an old pair of tights might work better. Just make sure the holes are small enough! To use it, you point the smaller tube at an insect and suck hard on the other. This pulls your query through the tube and into the vial, where they can be easily collected. This design was inspired the aspirator sold by Bioquip, and operates on the same principles.
Next up is one of my favorites, the Berlese Funnel. It is a device that uses heat to drive arthropods out of soil or leaf litter. These things are usually quite expensive, but I designed and built one for around $25. For complete instructions, you can visit instructables.com, where I’ve written a complete tutorial. To use it, litter is placed onto the screen in the tractor funnel and the light turned on. Any insects that are present attempt to escape the heat of the lightbulb, only to fall through the screen and into a jar waiting below. My design is based loosely on this image form the USDA
In the summer, when you turn a light on outside is is sure to draw an assortment of nocturnal insects. We can take advantage of this positive phototaxis using a device called a light sheet. To make this one, You need a portable light fixture, a light that fits in that fixture (I use a CFL black light which I found at Home Depot, because black lights attract more insects), a length of rope, clothespins, an old white sheet, and, if you aren’t close to an electrical outlet, a battery and inverter to power the light. First, tie the rope between two trees or posts or trees at a height of about six feet. Then, use the clothespins to suspend the sheet from the rope, making sure that it touches the ground with some slack. Finally, hook up your light and point it at the sheet so that is is illuminated. Night flying insects, such as moths and beetles, will be attracted to the light and land on the sheet. Some will hit it and slide down, which is why you need some slack at the bottom to catch them before they disappear into the grass. I first read about this method here
So, you’ve managed to collect your insects. Now what? Well, many make excellent short or long term pets, which gives you the opportunity to closely observe their behavior and life cycle. Most can be kept in simple setups, such as jars or terrariums. For many common insects, there are resources on the web detailing their care and feeding. Or, if you’re a little more adventurous, you can try to rear a more obscure insect using available information on its habitat and diet. One useful device for raising beetles and other insects with soil or wood dwelling larvae is a cardboard rearing box. It consists of, as its name suggests, a cardboard box with a tight fitting lid and a clear jar extending from a hole in its side. Material containing the larvae is place in the box and the box closed. When the adults emerge, they will likely be attracted to the light entering through the jar and accumulate there. However, not all adults will be attracted to light, so it is important to periodically check their progress.
Currently, I am using this box to raise Fire Colored Beetles from larvae I collected late November in Indiana. Since they have a tendency to cannibalize each other, I have placed each larva in its own ziplock bag full of rotting bark. This also keeps the medium moist, as it would be in the wild. Once they near adulthood, I will open the bags so that the beetles can reach the jar as intended.
If you want to permanently preserve the insects you find, then you will probably end up starting a pinned collection. However, before you can pin an insect it has to be dead. This is easier said than done, as many insects are quite delicate and liable to damage themselves if not dispatched correctly. One of the simplest ways to do this is by using a killing jar. To make one, first pour about an inch of plaster of paris into a jar with a tight lid and let is thoroughly dry. Then, add just enough rubbing alcohol or nail polish remover to dampen the plaster. Finally, stick a loosely wadded paper towel into the jar. This will soak up excess fluid and give the insects a place to hide. An insect place in the jar will quickly suffocate without inflicting serious damage upon itself. It can then be removed and pinned for your collection
Moths and butterflies will need to be spread before they dry in order to display their wings. A simple spreading board, pictured below, can be made from pieces styrofoam. The top pieces with the groove between them are held down with pins so that they can be adjusted based upon the size of the insect to be pinned.
If you don’t immediately spread an insect, it will become too brittle to work with. In order to reverse this, the specimen must be relaxed by placing it in a very humid environment. This can be achieved using an airtight box with a few inched of moist, milled peat moss in it. On top of the bed of peat is a sheet of styrofoam on which the insect is placed. A specimen left in the box will absorb the moisture from the air and become pliable. However, depending on the size of the insect, this can take one to several days. Try not to leave it in the box too long though, as mold is liable to develop.
Last but certainly not least is a place to keep your collection. The best option is a professional Shmitt Box, but if that is out of your price range there are a number of suitable DIY alternatives. However, please note that the latter will not protect you collection nearly as well as the former. The simplest would be a shallow box with a tight lid and a layer of styrofoam glued to the bottom. However, what’s the fun in keeping your collection hidden away in a drawer? So, last year I built a pair of glass fronted boxes to house my collection. I will not go into detail here about the construction, but if you want to build one try searching for shadow box plans.
If you do decide to keep your collection in a home made box, it is a good idea to periodically freeze your collection to keep any possible pests under control. Mothballs are also an effective deterrent, but tend to disappear quickly if you box is not entirely air tight.
The back of the box consist of a sheet of hardboard with insulation foam glued to it. Over the foam is a piece of poster board cut to fit the box.
As I have demonstrated here, most of the equipment needed to collect insects can be constructed using a few commonly available items and a whole lot of creativity. Below I’ve included a few links that feature other devices that I hope to construct in the future.
Links:
Collecting and Preserving Insects and Mites: Tools and Techniques: This is a great resource that includes plans for a number of devices as well as general insect collecting information
Manitoba Trap : This site provides instructions for building a Manitoba Trap, which is used to collect horseflies
Aquatic Trap: I haven’t tried this trap, but is extremely simple to build and appears to have worked quite well for the author
