JULY
2010

 

By
Tom Turpin
 
Professor of
Entomology
Purdue University

 

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07-22-10

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Capture Nets Used To Procure Insects


black and white photo of an older gentleman holding a butterfly net near bushes and trees
W.S. Blatchley, who served as Indiana State Geologist in the late 1800s and early 1900s, was also a respected entomologist.

The definition of net is an open-faced fabric woven into a mesh. Such fabric has been used to construct barricades to divide courts for volleyball or tennis or to enclose the backs and sides of a goal in soccer or hockey. Net fabric is also draped around a basketball goal to make it easier to see the ball go through the basket.

Netting material has also been used to provide barriers to keep animals out of an area. Screens over doors and windows are used to keep birds, mice and insects from invading our houses or other buildings. Nets are used to drape over ripening fruit on bushes or trees to keep birds from eating the fruit before humans harvest it.

Nets were once used to cover draft horses to help keep flies from biting the animals. Nets are still widely used to keep biting insects such as mosquitoes and black flies away from us. Beekeepers use a net, called a veil, to keep bees away from their heads and faces as they work with bee colonies.

The original use of net fabric was neither for sport nor as a barrier but to catch animals. Fish, birds and insects are creatures that sometimes end up in a net. Some nets are designed for the specific purpose of catching animals and are known appropriately as capture nets.

Capture nets were probably created for the purpose of fishing. Exactly when nets were first used for such a purpose is not known. For sure nets were being used as fishing devices in biblical times. Chinese pottery decorated with a fishnet design dates to 5000 B.C. Native Americans were using nets for fishing when the first Europeans arrived. These nets were fashioned from animal tissues and plant fibers, which were twisted and knotted into open-work meshes.

Also lost in antiquity is the exact time period that someone first adapted a fishing-type net for the purpose of catching an insect. The prototype for what is called an insect or butterfly net had probably been around for some time. In a poem about fishing written in about the year 178, the Greek poet Oppian described a scoop net held open with a hoop. Put a handle on it and that sounds like a description of a butterfly net to me!

In modern times insect capture nets - butterfly nets to the general population and most cartoonists - vary somewhat in structure. The net consists of three components: a handle, a circular ring and a cloth bag. The individual parts can vary greatly from net to net, but in general the circular ring should be at least 12 inches in diameter. The net should taper at the bottom and be at least twice as long as the diameter of the ring. Those dimensions allow the tip of the bag to be flipped over the ring to entrap insects in the net.

Almost any type of material is suitable for the cloth part of an insect net. It is best if it is strong and durable and open enough to view an insect through the mesh. Generally, the portion of the bag that fits over the ring should be constructed of a heavy fabric, such as canvas or muslin, because that part of the bag gets the most wear and tear.

In any endeavor the equipment used is sometimes specialized for specific purposes. So it is with nets used to collect insects. The typical net is constructed of lightweight mesh material. Such a net is used when the collector looks for specific insects and swings the net to try to make the capture. Some nets are made of heavier, more durable material and are called sweep nets. These nets are used to sweep vegetation and collect whatever insects are present. So-called dip nets are used to collect insects from the water. Nets with long handles are available to capture insects located high up in trees.

Insect capture nets can be purchased from a number of commercial sources. Most big-box and toy stores carry some version of insect nets. These nets normally are constructed of a course mesh material and are truly butterfly nets, because they allow smaller insects to escape through the mesh. Biological supply houses sell high-quality insect nets of all styles. In fact, nets that collapse and fit into small carrying cases or bags also are available. Just the thing for folks who want to travel light but always have the trusty capture net at hand when that rare butterfly flutters by!

 

 

Writer: Tom Turpin
Editor: Olivia Maddox