Blacklighting Tips
by Gary A. Dunn
(reprinted from Y.E.S. Quarterly 3(2), Spring 1986)
There are many ways to run a productive blacklight setup. There are endless variations of this collection method and practically everyone has developed a favorite method. I'd like to share two of my favorite methods for blacklighting.
The first method is most useful for blacklighting in open expanses. This is the method use when blacklighting for tiger beetles arid other insects at alkali flats and fields. I use a DC-powered blacklight unit that plugs into an automotive cigarette lighter.
Because the cord is not overly long (this tends to limit where I can set up the light), I have fashioned some simple, inexpensive extension cords. All you need is a length of 18 gauge lamp cord (I made one 50' and the other 100' in length), a cigarette lighter plug ("male") and a cigarette lighter receptacle ("female"). These materials are commonly available at hardware and automotive stores. Connect one end of the lamp cord to the cigarette lighter plug. Be sure to properly align the positive and negative wires. The plug's leads should be marked positive (+) and negative (-). The lamp cord has the positive wire grooved or striped in some fashion. Next, attach the cigarette lighter receptacle (again being sure to properly align the positive and negative wires). Generally, the positive wire will attach to the central part of the receptacle back end, and the negative wire must be attached to the outer cylindrical part of the receptacle. Wrap the areas where you have attached and spliced wires with black electrical tape. Your cord is now ready for use. I use an "H-shaped" wire caddy to keep my cord neat and tangle-free.
With my two extension cords I can set up my blacklight some 150 feet from my 4 x 4 pickup. In open areas I suspend my light beneath a camera tripod and allow the light to shine in all directions.
In these wide-open areas some insects, especially beetles actually walk up to the light. Many others fly to the lighted area and then run about on the ground. To easily catch these insects without having to individually grab each one, I simply place a couple of pie pans in the ground and fill them with a small amount of ethylene glycol (automotive antifreeze). While insects are busily falling into the pans you can devote your attention to the outermost reaches of the lighted area. Many insects sit in the shadows or the very periphery of the lighted area, never approaching the light. This is where a flashlight, headlamp, or lantern comes in handy to aid in collecting these "shy" insects.
The other blacklighting method I use involves the use of a white sheet and my 4 x 4 pickup (which has a camper cap on the back). I drape the sheet over either the back end or side of my truck, using rocks or sticks to hold it in place. I suspend the blacklight in front of the sheet on a horizontally protruding stick or net handle. It helps to adjust the sheet so that the bottom portion of the sheet rests on the ground in an "T-shaped" configuration. This way, any specimens that drop from the sheet as you're trying to get them in the jar will land on the sheet and can usually be caught.
Because this blacklight setup is one-directional, a certain amount of care must be taken in selecting the direction to shine the light. I find this method works well when I am trying to attract beetles from a specific habitat, such as beach, section of stream bank, marsh, or wooded area.
As with all collecting techniques, blacklighting is meant to be experimented with. Try different setups and be prepared to modify your setup in the field to meet varying conditions. Doing so will assure profitable blacklight collecting.
| This educational resource was prepared by the Young Entomologists Society, 6907 West Grand River Ave., Lansing MI 48906-9131, phone/fax 517-886-0630, e-mail YESbugs@aol.com. Support minibeast youth education - join Y.E.S. today! |