JULY
2011

 

By
Tom Turpin
 
Professor of
Entomology
Purdue University

 

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Check out these books by Tom Turpin:

Flies in the face of fashion

What's Buggin You Now?

 

 

 

07-28-11

Download the audio of On Six Legs: MP3, WMV.

Catching Insects for Fun or Profit


People want to catch insects for all kinds of reasons. Some want to make an insect collection for a 4-H project or a school assignment. Other people have an economic incentive for catching insects. That's because there is a market for some insects, especially brightly colored beetles and butterflies that are used in art and design. Sometimes we try to capture pest insects in order to keep them from doing damage -for instance, Japanese beetles that feed on our plants or wasps and yellow jackets that inflict stings.

Because of the human desire to capture insects, all kinds of contraptions have been developed for that purpose. Most insect-collecting devices fall into one of two basic categories. The first category could be called insect passive. That's because the insect doesn't have to do anything to be captured. The other type of insect capture device requires some action on the part of the insect to be successful.

The most common insect-passive devices are the appropriately named capture nets. In popular language capture nets are often called insect nets, bug nets or butterfly nets. Most cartoonists make sure that they depict an entomologist with insect net in hand.

The success of using a net to capture an insect depends on the ability of the person with the net. Swinging the net in the vicinity of the flying insect sometimes works. Picture someone with a net chasing a butterfly! Another approach with the net is to drop it over the location where the insect, say a bee or butterfly on a flower, is perched. The net can also be swung back and forth in vegetation in an activity known as sweeping. Such action results in insects in the vegetation being swept into the net.

The second type of insect-capture device depends on the behavior of the insect to make it work. Examples include sticky traps, glue boards, fly strips and flypaper. Because flies like to land on vertical surfaces, especially suspended strips of material, a dangling fly strip is an attractive resting site. Once the fly or other insect lands, it becomes entangled in the sticky material on the strip.

Some sticky traps use a bait to attract the insect. One such trap is sold by Black Flag and called the Roach Motel. This was one of the first commercial sticky traps for insect control and utilized food, and later a cockroach pheromone, as bait to attract the roaches. The advertizing tagline for the Roach Motel is, "Roaches check in, but they don't check out.®"

Pheromones are chemicals produced by animals. These chemicals elicit a response from individuals of the same species. Some pheromones function to attract mates. These so-called sex-attractant chemicals are frequently used to lure insects into traps. The Bag-a-Bug traps for Japanese beetles use both a sex-attractant and a floral odor to entice the beetles. In this case the flying beetles that are attracted by the odor crash into the wings of the trap and then fall into a collection bag suspended from the wings.

Traps also are available to capture stinging insects, including wasps and yellow jackets. Most of these traps use chemicals associated with food items such as meat or sugar for bait. Once lured into the trap the wasps, like the cockroaches in the Roach Motel, can't check out.

In general, insect traps have not proven effective in controlling undesirable pest insect populations. To be sure, insects end up in the traps, but research has shown that the number captured is insignificant relative to the numbers causing the problems.

However, sticky traps are effective for use in detecting the presence of insects or in estimating population levels. In this case the traps are important tools in insect management programs.

Sticky material used in traps of this kind is commercially available and is appropriately called tangle foot. So if you want to make your own sticky traps for catching insects you can do it. But a word of warning from someone who has done it, tangle foot sticks on more than insects!

 

Writer: Tom Turpin
Editor: Olivia Maddox