A simple insect bottle trap for healthier drylands (Willem Van Cotthem)

Insects can be a huge problem, particularly in the drylands.

Insect traps are mostly used to reduce or to study insect populations.  As a bait, one can use chemical attractants, pheromones, food (fruits, proteins, sugar, …) or visual lures.

Trap mechanisms can vary widely. Low-tech, cheap traps are mostly based on food.
Different types of traps are shown in this video : http://youtu.be/ciOeTmr1FLw

Designs differ according to the insect behaviour.  Mosquitoes and many other insects are attracted by bright colors, carbon dioxide, lactic acid, floral or fruity fragrances, warmth, moisture and pheromones. Flies and wasps are attracted by proteins.

One can find a description of bottle traps for insects at Wikipedia :

http://en.wikipedia.org/wiki/Bottle_trap_for_insects

A bottle trap is an insect trap made out of a plastic bottle. Most collectors use bottles of 1.5 or 2 liters, but smaller bottles can be used as well.

Funnel type. These bottle traps are made by cutting off  the complete tapering part of the bottle top. That part is placed upside down on top of the rest of the bottle (see photos below), thereby effectively forming a funnel.  After putting the bait in the bottle the trap is placed at the desired location.

Advantages: Insects, e.g. flies and wasps, can’t escape from this type of trap, since they fly up along the side of the bottle, not finding the exit, which hangs in the middle.

Disadvantages: Too much rain will also funnel into the trap. It is therefore normally used on dry locations or in dry seasons.

A simple, cheap, but effective one has been built with a soda bottle (See photos below) :

2011-10-15 - Homemade insect trap : Discard the cap of a soda bottle, cut the upper (tapering) part of the bottle and place it upside down on the body part of the bottle (Photo WVC)
2011-10-15 - Pour some sugar holding liquid (coke, soft drink, fruit juice, beer, ...) in the bottle to attract insects. These will enter the trap through the bottleneck and will try to escape along the wall, finally falling in the liquid. (Photo WVC)
2011-10-15 - Insects trapped in the liquid (Photo WVC)
2011-10-15 - Such a cheap insect trap keeps your environment healthier (Photo WVC)

Author: Willem Van Cotthem

Honorary Professor of Botany, University of Ghent (Belgium). Scientific Consultant for Desertification and Sustainable Development.