If you would like to collect insects for your classes or perhaps just for personal entertainment, here are some helpful material for you. You may think that collecting insects require a lot of fancy, expensive gear. The truth is, you can be adequately equipped with about twenty dollars, although if you want to have a net, that will cost a bit more. You can buy most of the items for the traps in a grocery store. The only items that I needed to acquire separately were nets and kill jars for collecting and pins, pinning box, and alcohol for preserving the specimens. Following are the three main methods I used to capture the bugs, followed by methods of preserving them.
1. Pitfall traps
These are one of the easiest traps to set, yet, also one of the most effective. Usually, insects that live on the ground are trapped in these; carabid beetles, ants, spiders, and others. It's a simple trap, requiring a small shovel, a large plastic cup, a small plastic cup that would fit in the larger one or the bottom half of the large cup, plastic dish, nails, and anti-freeze. You could do this with only the large cup, but then you would have to dig out the cup and re-bury it every time, which could be quite a pain.
When you are ready to set these traps, find a place with a small amount of disturbance, preferably in a forest or a place where the trap can be surrounded by plants. Then, dig a hole deep enough to completely bury the large cup and then fill the remaining space with the dirt that you dug up. It's important that you make the top of the cup even leveled with the soil around it. After you are done burying the cup, fill the small cup with anti-freeze and put it in the large cup so it fits snugly. Finally, poke three to four nails through the plastic dish and place it over the trap, with plenty of space between the ground and the plate, so that water won't go in when it rains.
After leaving the traps out for a week, take the small cup out of the large cup, leave the large cup buried unless you want to move the trap. Pour the anti-freeze, hopefully with arthropods in it, into a container and label it with date, location and the method. For instance, Sept. 13 2008 Plot A Pit. Labelling is important, as it is likely you won't remember where you caught them once you have about ten containers.
2. Bee bowls
Bee bowls are small traps, mostly used to capture various pollinators; bees, wasps, butterflies, syphid flies, and some other less common pollinators.
To set up bee bowls, you need soap water, small cup or bowl, and some markers or highlighters. Color the bottom and sides of the cup with the markers, preferably colors that resemble the flowers near which you will place the bee bowls. Then, find an area with flowers and place the bee bowls in various places after filling the cups up with soap water. Leave them out for a while and come back after a few hours. Hopefully, you will see some bugs and insects in the cups. If you do have some, pour each cup into a mesh net filter and collect the creatures. Finally, place them into a jar or a container with alcohol and label them. For instance Sept. 13 2008 Plot B BB (Bee Bowl).
3. Nets
This one is the most active and fun method of catching insects, although it can be tiring. All you need is a net and a kill jar. A kill jar is simply an airtight glass jar with some sort of absorbent material (usually plaster) soaked with poisonous material. Most people use ethyl acetate for the poison. Be sure to put in plenty of ethyl acetate or else the captured insects won't die. Here's what happens when you don't put in enough ethyl acetate in the kill jar. On my first outing, a beetle and a bumblebee revived after I pinned them, despite the fact that they had been in a jar with poisonous gas in a refrigerator for almost 24 hours. That was pretty strange, watching these insects struggle on the pin. I think it's much better to kill them quickly than to let them suffer on a pin, so don't try to get away with using a minimal amount of ethyl acetate!
Alright, so you have the kill jar ready and you have a net. Now, go outside, and go to an area where there are a lot of insects; near flower fields if you want a lot of pollinators or a forest if you want other types of insects. Using the net properly so that the insects don't escape is a tricky business. It's difficult to describe using words, but I will try. You have the net in two hands, right? Sweep at the insect from either right or left, I prefer right, and draw a large infinity symbol in the air. You know what that is: an 8 put sideways. Then, bring the net down to the ground, trapping the insect.
Now, this part depends on what kind of creature you captured. If it is a bee, fly, wasp, butterfly, or anything that fly around, you should lift the top part of the net while keeping the rim on the ground, so that the insect would fly up to the top. If it's a beetle, they will usually go DOWN, so you will have to twist the net to keep it trapped or just grab it with your hand or a tweezer.
After you have the arthropod trapped, you would want to put it in the kill jar. You have to be careful in this process because the insect could either escape or sting/bite you, especially if it's a bee or a wasp. This part is really hard to describe in words, so I will leave it to you to figure out the best way that suits you. I am going to try to post a link of a short video clip describing the process though, so don't be discouraged!
4. Other Methods: Expensive, but Effective
These are methods that I know how to use, but I haven't in my collection because the price of the equipments are a bit too much for a high school student's budget. Both the malaise trap and the UV light trap cost about $150 to $250. While they are much more expensive than the three methods mentioned earlier, these traps catch far more specimens than the other methods. I have seen a malaise trap capture over thirty different species and over a thousand specimen in a week. This is actually quite a staggering number of specimens and might be overwhelming for most people who plan to work alone.
The malaise trap is basically a large structure consisting of poles and screens. It relies on the general principle that bugs fly upwards when they run into an object. After the trap is set up, it is left out for a week or two, during which, bugs will fly into the screens, fly upwards, and ultimately end up in a small collecting jar with anti-freeze in it that would kill and preserve the specimens until you collect them.
The UV trap is also an effective means of capturing nocturnal insects, especially beetles and moths, although some non-nocturnal species are captured as well. The UV trap has one fundamental difference from the malaise trap in that it relies on the fact that the specimens would go DOWN instead of up as in the malaise trap. Beetles that fly into the metal plates of the trap would go down and fall into the anti-freeze. The UV light also attracts various nocturnal insects during the night that fly to the trap and end up in the anti-freeze. This method can also capture hundreds of specimens a week, depending on where you leave it out.
I haven't posted as much detail on the two traps as I have on the previous methods because I haven't used them as much. If you would like more help, feel free to contact me by email.
5. How to Preserve Your Collection
More important than collecting is preserving your specimens. There are two main ways of preserving them: pinning the specimens or putting them in alcohol. I prefer pinning as they are better for displaying, but if you have a lot of specimens of the same species, you should pin only the best looking ones and put the rest in alcohol.
There are different sizes of pins that you can use to pin the insects, ranging from size 0 to 7. However, most people would use size 1, 2, and 3 as those would accommodate most common insects. There are different rules you must follow for each type of specimen that you want to pin. First of all, it is generally not advisable to pin spiders or soft-bodied hemipteras. They tend to shrivel up when they are pinned, and thus, are much better off placed in alcohol. For butterflies and moths, you need a spreading board in order to spread the wings out. Although you can buy these, you could just use a Styrofoam board. After pinning the specimen through the middle of its thorax, pin it to the spreading board, spread out its wings, and indirectly pin the wings to the board using small slips of paper. (Click here for a picture) For bees and wasps, pin them through their thorax on their right side. For beetles, pin them through the elytra, on the right side in this case as well. When pinning any specimens other than moths and butterflies, it is important that you pin to one side of the specimen, in case there are important marks in the middle of the specimen that you would need to identify it later.
Pinning for small insects require a completely different process. Some insects are so small that pinning them directly would damage the specimen or make them unidentifiable. For small insects, use a small, triangular sliver of paper, pin the paper through the thicker side, and glue the insect to the point of the triangle. (Click here for a picture) Be careful not to get the glue all over the specimen as that might cover important regions.
Once the specimens are pinned, it is important that you put the specimens all at the same height on the pin as well as have them labeled. For this, you would use a pinning block, which is just a wooden block with three different heights: highest for the specimen, middle for location label, and lowest for species label. Just push the pin through the hole until the pin touches the ground, insuring that the specimen is at the correct height. For the labels, you need a location label and a species label. The location label comes first, with information on where, when, and how you caught the specimen. For the species, you put the species name, the species' discoverer, and who identified it. There is a specific size and format for the labels, which you can see here and here.
For spiders, soft-bodied hemipteras or species that you already have pinned specimens of, you can preserve them in alcohol. The important thing is that you don't just use alcohol that you can purchase at a grocery store or a pharmacy. Those are about 20-30% alcohol, which is not pure enough to act as a preservative. Instead, you have to purchase special alcohol for lab usage, which is either 95% or 99%. Obtain a small glass vial, which you can purchase, put the specimen inside, fill it with alcohol, and put in a label, just as you would with a pinned specimen. If you are certain that some specimens are from the same species, you can put them in the same vial.
Finally, there is another way of preserving specimens that I have not tried yet, but plan to do so soon. This method is NOT for the purpose of keeping them for identification, so I advise that you do not use this method unless you have ton of specimens of some species that you are sure you won't need for identification. This method is quite tricky and there is a chance you could mess up, especially on your first few tries, so I would use common specimens that you can afford to lose. For this, you need plastic molds and resin that you can buy on Amazon online or in most arts and crafts stores. The process is quite simple, as you just mix the resin and the catalyst as the instruction states, pour the resin about halfway into the mold, place the specimen and wait for the resin to harden a bit. This is often tricky as some specimens refuse to stay in the correct position. You have to constantly watch over the molds and make sure the resin hardens with the specimen in the correct position. Then, when the bottom part hardens enough to keep the specimen stuck, fill the rest of the mold and let the resin harden for a week or two. Then, cautiously remove the blocks from the mold; this is difficult to do at first without damaging the resin blocks, so practice a bit beforehand. These resin blocks can be used for classes as well as decorations. Last word of warning; make sure you wear gloves when making the resin blocks and that you leave them in a well ventilated room, as resin vapor can be toxic to breathe and can damage the skin.
