This technique consists in attracting the phasmids with a light.
Basic equipment needed:
- Water-proof headlamp and batteries. Additional hand lamp with batteries.
- A portable generator (e.g. Honda 10i) or suitable batteries for the light source that will be used.
- A powerful light source (e.g. strong super actinic or black-light bulb).
- Butterfly net.
- A white sheet or similar.
- A stable but lightweight frame and ropes for fixing the reflecting surface.
- Plenty of differently sized plastic containers.
- Camera and macro equipment (lens and flash). Batteries.
- GPS or smartphone with an App to take coordinates.
Summary of the workflow for this method:
- Explore the area during the daytime to be more familiar with it and find suitable areas to place the light trap.
- Set up the light trap during the sunset and take coordinates.
- Wait until phasmids arrive and/or search on the enlighted shrubs nearby.
- When finding a phasmid, take pictures.
- Collect the phasmid and put them carefully in the plastic container.
Detailed information:
Another method which enables to collect special species spectrums is the use of a light-trap which is due to being exceptionally sufficient for these insects broadly used by entomologists studying flying insects such as Lepidoptera, Coleoptera, Ensifera or Heteroptera. This method is however not very sufficient for phasmids and usually, the collected insects restrict to single specimens of well-flying species which may not be found with "Method I" or male specimens. Generally, males show a stronger tendency of being attracted to light and in some cases the numerous other insects may be more interesting than the single phasmids.
The function of a light-trap is quite simple. One needs a strong light-bulb (if possible a super actinic bulb or black-light), which is supplied with electricity by using a power supply (generator or battery) and a large white reflecting surfaces (a white sheet or a wall). Slightly raised clearings or forest borders have proven to be the most sufficient localities, due to enabling the insects to see the light from far distance. The most prolific time-span in the tropics seems to be between 11 and 12 pm.
When the light-trap is completely installed, patience is needed. Often it takes hours that, except uncountable other insects, the first phasmid is attracted by the light. It is also a good idea to search the surrounding vegetation as well, as some insects may not directly sit on the enlighted surface but on the slightly enlighted shrubs nearby.